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Review Article
 

Plant as a Source of Natural Antiviral Agents



Muhammad Nouman Sohail, Fiaz Rasul, Asia Karim, Uzma Kanwal and Idress Hamad Attitalla
 
ABSTRACT

Viruses are one of the main hazards for both humans and animals. They enter in the living body and redirect body’s metabolism to produce large copies of their genome and proteins. Diseases caused by these viruses are difficult to tackle with the help of currently available antiviral drugs. So the aim of this study was to explore the plants with reported antiviral activity, to get understanding for better control of these viruses. Herpes virus, Human Immunodeficiency Virus (HIV), influenza and hepatitis virus were at top among all studied viruses. Prominent modes of action against these viruses were inhibition of viral entry and its replication in host cell. Against RNA viruses plants mainly targeted their Reverse Transcriptase (RT) enzyme (like HIV) or protease (mostly found against hepatitis C virus). A range of active compounds have been identified which could be the potential antiviral agents for future drug development. Some plants like Allium sativum, Daucus maritimus, Helichrysum aureonitens, Pterocaulon sphacelatum and Quillaja saponaria emerged to have broad spectrum antiviral activity. Detail study of their phytochemicals and mode of action against these viruses could be help full for more effective control of hazardous viruses.

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Muhammad Nouman Sohail, Fiaz Rasul, Asia Karim, Uzma Kanwal and Idress Hamad Attitalla, 2011. Plant as a Source of Natural Antiviral Agents. Asian Journal of Animal and Veterinary Advances, 6: 1125-1152.

DOI: 10.3923/ajava.2011.1125.1152

URL: https://scialert.net/abstract/?doi=ajava.2011.1125.1152

INTRODUCTION

Virus "a piece of bad news wrapped in a protein coat" has been defined by Peter Medawar (Oldstone, 1993). It appears as the perfect definition after considering the list of top ten causes of death in low, middle and high income countries. Lower respiratory infections, diarrhoeal diseases and HIV/AIDS are the common death causes among low and middle income countries (WHO, 2011b). All of these three health disorders are directly or indirectly caused by viruses. Except lower respiratory infections none of the above mentioned factors are prevalent among high income countries. It clearly indicates that how severely these viral diseases are affecting the people health in low and middle income/developing countries.

Our planet contains nearly 1031 viruses and their ubiquity also invaded the marine environment, where in every 200 liter of water nearly 5000 viral genotypes are present (Breitbart and Rohwer, 2005; Suttle, 2005). Moreover viruses are moving between the environments and they are present almost everywhere e.g. deep sea, polar ice, alkaline, hot and saline waters and more than 2000 m deep in terrestrial environment. There are almost 20 families of viruses that actually infect humans (Harvey et al., 2006) and some of them also cause diseases in animals (Mahzounieh et al., 2006). The diseases they cause in human include chickenpox, influenza, skin rash, hepatitis, bronchiolitis, acquired immunodeficiency syndrome, liver infection and many others. Virus particles enter in the living system and if they overwhelm the body’s immune system then it is almost impossible to stop their spread in body. They direct the host metabolic pathway for the sake of their repeated replication; this makes their treatment difficult. But fortunately, it is now well known that viruses are unique in their mode of replication, which can be easily targeted (Selisko et al., 2007; Syed et al., 2010). They use specific enzymes to infect and replicate, whose inhibition could arrest their metabolism. For example, the proteolytic enzyme promotes virus maturation by separating the viral polyprotein precursor, whose inhibition will stop its maturation (Wapling et al., 2007). So the virus metabolism or replication can be stopped by specific inhibitors.

Today many synthetic antiviral drugs e.g. moroxydine, ganciclovir, valganciclovir, valaciclovir etc. are used, which inhibit the virus replication via different mechanisms (Biron, 2006; Czeizel et al., 2006). But difficulty in drug treatment arises due to their low efficiencies, cytotoxicity and development of viral resistance against them. Another antiviral treatment; vaccination, can be applied but they are still under development, as they often provide incomplete protection against virus and their reliability needs more research (Pervez, 2000b; Subbarao and Joseph, 2007). Thus the treatment through antiviral synthetic drugs and vaccines need more scientific investigation. Nature provides another, more reliable source of antiviral agents; viz. plants phytochemicals; almost 40% of currently available drugs are direct or indirect derivatives of plants. A number of ethnobotanical studies aiming to identify potential therapeutic plants for more effective control of health issues demonstrate the importance of plant species in health care system (Shinwari and Khan, 2000; Heneidy and Bidak, 2004; Appidi et al., 2008; Ky et al., 2009; Ansari and Inamdar, 2010; Makambila-Koubemba et al., 2011). Plants are rich source of phytochemicals like alkaloids, anthocyanins, carotenoids, flavonoids, isoflavones, lignans, monoterpenes, organosulfides, phenolic acids, saponins and many more (Al-Yahya, 2005; Hassan et al., 2006; Anitha and Ranjitha Kumari, 2006; Akomo et al., 2009; Rahman et al., 2009; Amabeoku and Kinyua, 2010; Ndjonka et al., 2010). These phytochemicals have been proved to be responsible for their antimicrobial (Sampathkumar et al., 2008; Krishnan et al., 2010), antihypertensive (Amalia et al., 2008), anti-diabetic (Qureshi et al., 2009), antioxidant (Momtaz and Abdollahi, 2010), hepatoprotective (Mahalakshmi et al., 2010; Ansari et al., 2011), cardioprotective (Ojha et al., 2008; Fard et al., 2008) and other therapeutic activities. Thus this study is aimed to analyze the previously reported antiviral plants and identify potential mode of action and compounds that are responsible for their antiviral activity. Better understanding of natural antiviral agent’s mode of action and identification of responsible compounds will be helpful to provide a new insight for the development of new antiviral drugs for more effective viral control.

Basic viral structure and its mode of action: Viruses are organic objects, which are metabolically inactive outside the host body but become active on their entry into the host cell (Dupre and O'Malley, 2009). These are mainly composed of proteins and nucleic acid; the proteins majorly contribute to their specific shape and form a coat called capsid (Andersson, 2010). Thus viruses are of various shapes e.g. simple, helical, icosahedral or complex and some viruses are surrounded by a lipid bilayer, derived from host membrane, which is called as envelope (Geng et al., 2007; Raja et al., 2003). Some capsid proteins are also associated with virus nucleic acid and called as nucleocapsid, while nucleic acid proteins, are the direct part of the nucleic acid, known as nucleoproteins. The nucleic acid of virus is either made up of DNA or RNA, is the basic source of information required for the regulation of its metabolic activities. Theses DNA and RNA can be further divided into two types depending upon the number of strands i.e. single stranded or double stranded DNA/RNA (Firth et al., 2010; Pichlmair et al., 2006). The single stranded RNA viruses can be further distinguished depending upon the sense of strand as some RNA viruses have positive-sense RNA (+VE ssRNA) and some viruses have negative-sense RNA (-VE ssRNA) (Gorbalenya et al., 2006). The shape of nucleic acid (DNA/RNA) is also an important source of differentiation, because all the viruses did not contain same-shape nucleic acid (Gao and Hu, 2007). It can be either in circular, linear or coiled form.

Virus (either DNA or RNA) life cycle can be divided into some predefined stages; adhesion, adsorption (entry), replication, maturation and release, which involve some enzymes and proteins. For example, the process of virus entry is carried out by cell surface proteins; HCV entry involves claudin-1, occludin, tetraspanin as main receptors proteins (Burlone and Budkowska, 2009). Its entry is also mediated by some other lipoproteins and an enzyme; lipoprotein lipase. On the other hand the influenza virus infection is mediated by protease enzyme, which activates the viral surface protein haemagglutinin (Zambon, 2001). The protease enzyme is also important in the expression of viral proteins; it splits the proteins into groups depending upon their structural and nonstructural functions (Appel et al., 2006). But the RNA viruses need two additional enzymes for their survival; reverse transcriptase and integrase, former transcribes the viral RNA into DNA at the time of replication (Briones et al., 2010; Sluis-Cremer and Tachedjian, 2008). While the second enzyme is used to incorporate the viral DNA into host genome, furthermore it is also needed for proper uncoating of virus core proteins. Thus virus is needy of enzymatic and non-enzymatic proteins, which can be targeted to stop their replication and infection.

Antiviral plants: In this review a total of 105 plant species have been identified that were reported for their potential antiviral activities (Fig. 1). Maximum number of plants were reported for their activity against herpes viruses, indicating that herpes viruses were the highly studied viruses with respect to antiviral plants. After herpes virus, HIV, influenza and hepatitis were among other viruses that were addressed in most of the studies in order to discover the plant with antiviral properties. In next sections a brief description with respect to the available antiviral plants against some important viruses has been provided.

Plants with antiviral activity against herpes virus: An enveloped double stranded DNA virus with linear genome; it belongs to the family Herpesviridae, which is recently reclassified to separate the mammal’s virus from other non-mammalian viruses (Davison et al., 2009). It is also known as human herpesvirus and Varicella-zoster virus.

Fig. 1: Mostly studied viruses found during current review

It is highly infectious and prevalent disease especially in developing countries with almost 50 % prevalence in adults, disease symptoms are often unnoticeable (WHO, 2001). It is a sexually transmitted disease and highly prevalent in females as they often get infected with it before the age of fertility (Ziyaeyan et al., 2007). It also causes febrile rash and graft-versus-host disease in humans, who got hematopoietic stem cell transplantation (Pichereau et al., 2011). It is also the casual agent of genital herpes disease; vaccines against it are currently under developmental stages (Soleimanjahi et al., 2007).

Total 57 plants were identified with antiviral activity against herpes virus (Table 1). Binns et al. (2002) reported that h-hexane extracts of Echinacea purpurea showed in vitro antiviral activity against herpes virus in another study polysaccharide and cichoric acid were found among the active phytochemicals of various plant parts extracts (Vimalanathan et al., 2005). Another compound of Phyllanthus urinaria from its acetone extract (hippomanin A) showed its activity against herpes simplex virus type 2 (Yang et al., 2007); in another study Cheng et al. (2011) identifies a compound (excoecarianin) from this herb with same activity. Anthraquinones has been identified as potential compound responsible for antiviral properties of Rhamnus frangula, Rhamnus purshianus and Rheum officinale (Sydiskia et al., 1991). This organic compound has also been reported in many studies to be responsible for positive health attributes of many medicinal plants (Kumar et al., 2007; Hussein et al., 2010; Karou et al., 2011; Mbaya and Ibrahim, 2011; Sonibare et al., 2011). Kurokawa et al. (1999) reported the antiviral activity of Rhus javanica against herpes virus and found moronic acid as potential active agent from its herbal extract. Plants mainly showed activities like restriction of entry host into cell (Weber et al., 1992; Zandi et al., 2007), reduced viral replication (Duarte et al., 2001; Chiang et al., 2003; Alche et al., 2003) and partial destruction of viral envelope (Sydiskia et al., 1991). Active compound present in most of the plants were anthraquinones, terpenes, quercetin, lectins and phenolics (Amoros et al., 1987; Sydiskia et al., 1991; Chiang et al., 2003; Ooi et al., 2004; Kan et al., 2009). Allium sativum is a medicinal plant with a lot of health benefits (Ishtiaq et al., 2007; Sukandar et al., 2010; Abdelaziz and Kandeel, 2011; Weber et al., 1992) found its extract effective against this virus. The extract of Aloe vera another important medicinal plant (Alqasoumi et al., 2008; Semalty et al., 2010) has been reported to be effective against this virus by inhibiting the viral entry and replication into the host cell(Zandi et al., 2007).

Plants with antiviral activity against HIV: HIV is highly infectious enveloped virus of family Retroviridae; it has liner ssRNA positive sense genome and cause high morbidity. During year 2004, HIV infection was one of the leading factors responsible for almost 2.65 million deaths in low income countries (Patton et al., 2009). It is also prevalent in high income countries, as in United States almost 55400 new HIV cases were observed each year from 2003-06 (Hall et al., 2008). It increases the chances of bacteria and other viruses infections, which poorly effects the health; transmission of HIV from mother to child could lead to the death (Corbett et al., 2003; Ahasan et al., 2004; Ilboudo et al., 2007; Abongo et al., 2008). Its chemo-treatments are scarce, because of their potential side effects on human body, non-significant efficiencies and increased divergence in HIV genome (Fokunang et al., 2006; Jaffary et al., 2007; Kagone et al., 2011). But a nutrient rich food can reduce the HIV caused decreased weight and help in improving the patient’s health (Oguntibeju et al., 2007).

In present study 26 plant species were found effective against HIV. Terpenoids, lectins, alkaloids and flavonoids were common among the active compound of these plants (Table 2). Roja and Heble (1995) reported the positive activity of an alkaloid (castanospermine) isolated from seeds of Castanospermum austral against this virus.

Table 1: Detail description of studies focusing on antiviral plant activities against herpes virus

n/a: Not available

Table 2: Detail description of studies focusing on antiviral plant activities against HIV

n/a = Not available

Wang and Ng (2001) reported that gossypol and alkaloids of Corydalis yanhusuo might be responsible for it inhibitory activity on HIV virus. Ethanolic extract of Monotes africanus, which is a rich source of various flavonoids has been reported for its antiviral activity against HIV (Meragelman et al., 2001; Reutrakul et al., 2007). Most of the plants mainly affect the Reverse Trancriptase (RT) activity or penetration of virus particles into host cell. Calanolides which exhibits potential RT inhibitory activity have been found in the hexane extract of Calophyllum brasiliense leaves (Cesar et al., 2011). The hexane extract of this plant was found to have inhibitory effect on RT enzyme of HIV. Lectins derived from Phaseolus vulgaris are reported for their potential inhibitory effect on HIV RT activity (Ye et al., 2001; Fang et al., 2010). Another seed protein isolated from Vigna unguiculata possesses the same effect on RT activity in addition to inhibitory effect on glycohydrolases α- and β-glucosidases (Ye et al., 2000; Ye and Ng, 2001). Oh et al. (2011) reported that aqueous extract of Prunella vulgaris interferes with the viron post binding events. Extract of Rhizophora mucronata and Rhizophora apiculata (a rich source of polysaccharides) blocks the viral binding to the cell surface (Premanathan et al., 1999a; Premanathan et al., 1999b). In another study Lee-Huang et al. (1995) studied the effect of a protein isolated from Gelonium multiflorum and found that it reduces the virus replication by inhibiting the integration of viral DNA into host genome. Panax ginseng, which is also effective against cardiovascular diseases (Jun et al., 2007) has been reported to be effective against HIV by inhibiting the RT activity (Ng and Wang, 2001). Ricinus communis an important medicinal plant (Onwuliri and Anekwe, 2001) showed inhibitory effect on RT and N-glycohydrolases of HIV (Wang and Ng, 2001). Another plant Terminalia chebula, which has been proven to have many beneficial medicinal properties (Gupta et al., 2008a, b; Shinde et al., 2009; Anam et al., 2009) posses significant anti-HIV activity (Lee et al., 2011). Its methanolic extract showed antiviral activity against HIV when tested on virus infected baby hamster kidney cells.

Plants with antiviral activity against influenza virus: It is a single stranded RNA virus with negative sense linear fragmented genome enclosed in a capsid, it belongs to family Orthomyxoviridae and infects both mammals and birds. It has seasonal epidemiology and mainly spread through air when the environment is dry and cold (Lowen et al., 2007). The hospitalization and death rate associated with influenza vary with the age and type of virus, as influenza virus A-caused infection rate is higher than type-B (Thompson et al., 2004). Influenza virus, especially of avian origin is highly virulent disease causing agent in humans and birds; it has long history, put huge burden on human health since 1580 (Farooq et al., 2006; Lazzari and Stohr, 2004). It is responsible for deaths of millions of people; its pandemic nature is due to its variable strains which develop via the reassortment of genetic information. Thus the development of vaccine against it is difficult both in humans and birds.

Sixteen plants were identified which showed antiviral activity against influenza virus. Anthocyanin and polyphenols were among the commonly found active phytochemicals in these plants (Table 3). Camellia sinensis is an important herbal plant having significant antioxidant, photochemoprotective, hyperglycemic, antibacterial and many other beneficial heath benefits (Adiloglu and Adiloglu, 2006; Bakar et al., 2006; Shokrzadeh et al., 2006; Hassani et al., 2008; Mohamed and Metwally, 2009; Amutha et al., 2010; Chakraborty and Chakraborti, 2010; Kaur and Saraf, 2011; Obaid et al., 2011). Catechin derivatives obtained from the tea of this plant showed significant inhibitory effect on influenza strains (Song et al., 2005).

Table 3: Detail description of studies focusing on antiviral plant activities against influenza virus
n/a = Not available

Ehrhardt et al. (2007) found that Cistus incanus possess the antiviral activity by modulating the viral surface in order to inhibit its entry into Madin-Darby Canine Kidney (MDCK) cells. Inhibitory effect against influenza virus has also been reported in human patients (Kalus et al., 2009). Another herb Echinacea purpurea also restrict the viral entry by inhibiting the binding of viral receptors to the host cells surface (Pleschka et al., 2009). Geranium sanguineum, a rich source of polyphenols showed antiviral activity by effecting the expression of viral proteins on cell surface (Serkedjieva, 1996; Sokmen et al., 2005). A lectin isolated from bulbs of Narcissus tazetta showed significant antiviral activity against various strains of influenza virus (Ooi et al., 2010). In another study Ooi et al., 2004) reported the anti-influenza activity of a lectin isolated from saline extract of Pandanus amaryllifolius leaves. Scutellaria baicalensis an important medicinal plant (Yeh et al., 2010) possess a compound (isoscutellarein-8-methylether) which is thought to be responsible for it antiviral activity against influenza virus (Nagai et al., 1995).

Plants with antiviral activity against Hepatitis C Virus (HCV): Hepatitis C is an enveloped virus with +VE single stranded linear RNA, which belongs to the family Flaviviridae. It cause mild-chronic liver disease infecting more than three million people each year, which results in almost 350 000 deaths (WHO, 2011a). It has worldwide spread with 4.8% infection rate in Pakistan. It is a global problem nearly affecting 130 million people; moreover, alone it is responsible for about 27% of cirrhosis and almost 25% of world’s hepatocellular carcinoma (Alter, 2007). Its high spread is attributed to poor moral and health conditions, use of drugs, alcohol and contaminated syringes (Roshandel et al., 2007; Zakizad et al., 2009). It is detectable through serum proteins and blood analysis; its chemotherapeutic treatment is difficult but can be treated through herbal products (Ansari et al., 2011; Joseph and Raj, 2011; Pervez, 2000a; Moundipa et al., 2007; Tabassum et al., 2000).

In current study six plants have been identified with proved antiviral activity against HCV. Mainly plant showed inhibitory effect on HCV protease. Hussein et al. (2000) reported the inhibitory effect of Trachyspermum ammi and Embelia schimper methanol extract on HCV protease. Solanum nigrum which also exhibits hepatoprotective activity (Subash et al., 2011) has also been reported to have inhibitory effect on HCV (Javed et al., 2011). Cannabis a commonly used drug (Richardson, 2010) is a phytochemical of Cannabis sativa a medicinal plant with many beneficial health effects (Arshad and Khan, 2000; Qureshi et al., 2001; Tehranipour and Ebrahimpour, 2009). Acacia nilotica has remained the focus of many studies for its multipurpose applications (Shirazi et al., 2001; Banerjee et al., 2004; Ghosh et al., 2004; Elkhalifa et al., 2005; Emtehani and Tabari, 2007) its acetonic and methanolic extracts have sown anti-HCV effect on liver cells (Rehman et al., 2011). Sylvestre et al. (2006) reported the anti-HCV activity of cannabis in human patients. Mainly these plants showed their activity against HCV by targeting its protease (Table 4).

Plants with antiviral activity against respiratory syncytial virus: It belongs to the family Paramyxoviridae and is single stranded RNA virus, which is enclosed in an envelope. It is a highly prevalent virus throughout the world with large variation in its genome (Trento et al., 2010). It cause bronchiolitis and other respiratory problems and is a major cause of lower respiratory tract infections; it mostly infects the children under age of six months and also responsible for asthma problems (Mohapatra and Boyapalle, 2008). It causes an infection in 3-7% of healthy adults and 4-7% in the non-healthy adults, who already suffers from lung and heart diseases (Falsey et al., 2005).

Table 4: Detail description of studies focusing on antiviral plant activities against hepatitis, respiratory syncytial virus and vesicular stomatitis virus
n/a: Not available

Moreover it cause burden on population equal to that of influenza A virus, as the patients needs more health facilities and care. Ma et al. (2001) found that ethanol extract of Selaginella sinensis possess significant activity against respiratory syncytial virus. They further elaborated that this activity of plant could be due to the presence of a biflavonoid (amentoflavone) in its plant extract. A lectin isolated from Narcissus tazetta also showed antiviral activity against this virus (Ooi et al., 2010). Li et al. (2005) reported the Schefflera heptaphylla antiviral activity against respiratory syncytial virus and concluded that this activity was due to the inhibition of fusion of viral particles to the host cell.

Plant with broad spectrum antiviral activity: Based on the data presented in Table 1-5 plant with broad spectrum antiviral activity (plants reported for their antiviral activity against two or more than two viruses) were identified. Total 24 plants were found that were resistant to two or more than two viruses (Fig. 2). Two plant species showed antiviral activity against four viruses.

Fig. 2: Plant with broad spectrum antiviral activity

Table 5: Detail description of studies addressing rarely studied viruses
n/a = Not available

Allium sativum showed resistance against Herpes virus, Parainfluenza virus-3, Rhinovirus and Vesicular stomatitis virus. Daucus maritimus has been reported for its activity against Dengue virus, Hepatitis C virus, HIV and West Nile virus. Helichrysum aureonitens, Pterocaulon sphacelatum and Quillaja saponaria have been reported for their antiviral activity against three viruses each. As shown in figure 2 Helichrysum aureonitens is effective against Coxsackievirus, Herpes virus and Reovirus. Pterocaulon sphacelatum showed antiviral activity against Herpes virus, Picornavirus and Polio virus. Quillaja saponaria has been reported for its activity against Herpes virus, HIV and Reovirus. Almost all plants with broad spectrum activity were effective against herpes viruses. Moreover five plants which were effective against Herpes virus, also showed antiviral activity against Influenza virus. In the same way three plant species showed resistance against both Herpes virus and Vesicular stomatitis virus.

CONCLUSION

Majority of the studied viruses belongs to the Flaviviridae, Herpesviridae and Picornaviridae family. A large number of plants are available in nature which could act as a source of lead antiviral compounds. Mainly these plants target the enzymes that are involved in replication and integration of virus into host cell. In case of DNA viruses restricted entry of viral particles into host cell or inhibition of viral replication into the host cells were most frequent mode of actions. Destruction of viral envelop was also one of the identified mode of action against DNA viruses. RT plays a significant role in replication of RNA viruses and most of the plants restrict the activity of RT enzyme of virus. In order to design effective drugs against viruses their enzymes that are involved in the key metabolic activities (integration, replication) should be focused. A lot of plant population with possible potential is still uncovered as few plants have been studied in detail in order to identify the active phytochemicals against these viruses. More detailed studies in future will help not only to identify the potential antiviral compounds but also in better understanding of their mode of action for more effective control of these lethal viruses.

REFERENCES
Abdelaziz, I. and M. Kandeel, 2011. The protective effects of Nigella sativa oil and Allium sativum extract on amikacin-induced nephrotoxicity. Int. J. Pharmacol., 7: 697-703.
CrossRef  |  Direct Link  |  

Abongo, B.O., M.N.B. Momba, V.K. Malakate and J.N. Mwambakana, 2008. Prevalence of Escherichia coli O157:H7 among Diarrhoeic HIV/AIDS patients in the Eastern Cape Province-South Africa. Pak. J. Biol. Sci., 11: 1066-1075.
CrossRef  |  PubMed  |  Direct Link  |  

Abu Bakar, M.F., A.H. Teh, A. Rahmat, F. Othman, N. Hashim and S. Fakurazi, 2006. Antiproliferative properties and antioxidant activity of various types of Strobilanthes crispus tea. Int. J. Cancer Res., 2: 152-158.
CrossRef  |  

Adiloglu, A. and S. Adiloglu, 2006. An investigation on nutritional status of tea (Camellia sinensis L.) grown in eastern black sea region of Turkey. Pak. J. Biol. Sci., 9: 365-370.
CrossRef  |  Direct Link  |  

Ahasan, M.M., M.M. Billah, M.M. Hasan, K.M.D. Islam and J.A. Shilpi, 2004. Transmission, biochemical manifestation and CD4+ cell count of HIV: A review. Pak. J. Biol. Sci., 7: 292-300.
CrossRef  |  Direct Link  |  

Akomo, E.F.O., C. Zongo, S.D. Karou, L.C. Obame, A. Savadogo, C. Atteke and A.S. Traore, 2009. In vitro antiplasmodial and antibacterial activities of Canthium multiflorum schum and thonn (Rubiacea) extracts. Pak. J. Biol. Sci., 12: 919-923.
CrossRef  |  PubMed  |  Direct Link  |  

Al-Yahya, M.A., 2005. Preliminary phytochemical and pharmacological studies on the rind of pomegranate (Punica granatum L.). Pak. J. Biol. Sci., 8: 479-481.
CrossRef  |  Direct Link  |  

Alche, L.E., G.A. Ferek, M. Meo, C.E. Coto and M.S. Maier, 2003. An antiviral meliacarpin from Leaves of Melia azedarach L. J. Nat. Res. Part C: Biochem. Biol. Biophys. Virol., 58: 215-219.
Direct Link  |  

Allahverdiyev, A., N. Duran, M. Ozguven and S. Koltas, 2004. Antiviral activity of the volatile oils of Melissa officinalis L. against Herpes simplex virus type-2. Phytomedicine, 11: 657-661.
CrossRef  |  PubMed  |  Direct Link  |  

Alqasoumi, S.I., T.A. Al-Howiriny and M.S. Abdel-Kader, 2008. Evaluation of the hepatoprotective effect of Aloe vera, Clematis hirsute, Cucumis prophetarum and bee propolis against experimentally induced liver injury in rats. Int. J. Pharmacol., 4: 213-217.
CrossRef  |  Direct Link  |  

Alter, M.J., 2007. Epidemiology of hepatitis C virus infection. World J. Gastroenterol., 13: 2436-2441.
Direct Link  |  

Amabeoku, G.J. and C.G. Kinyua, 2010. Evaluation of the anticonvulsant activity of Zanthoxylum capense (Thunb.) Harv. (Rutaceae) in mice. Int. J. Pharmacol., 6: 844-853.
CrossRef  |  Direct Link  |  

Amalia, L., E.Y. Sukandar, R.M.A. Roesli and J.I. Sigit, 2008. The effect of ethanol extract of kucai (Allium schoenoprasum L.) bulbs on serum nitric oxide level in male wistar rats. Int. J. Pharmacol., 4: 487-491.
CrossRef  |  Direct Link  |  

Amoros, M., B. Fauconnier and R.L. Girre, 1987. In vitro antiviral activity of a saponin from Anagallis arvensis, Primulaceae, against herpes simplex virus and poliovirus. Antiviral Res., 8: 13-25.
CrossRef  |  Direct Link  |  

Amutha, M., R. Arunachalam, M. Umamaheswari, A. Usharamalakshmi, S. Ramakrishnan and G. Annadurai, 2010. Medicinal use of Camellia sinensis on lactose intolerance. J. Biol. Sci., 10: 112-116.
CrossRef  |  Direct Link  |  

Anam, K., R.M. Widharna and D. Kusrini, 2009. α-Glucosidase inhibitor activity of Terminalia species. Int. J. Pharmacol., 5: 277-280.
Direct Link  |  

Andersson, S., 2010. General polyhedra, virus structure and mutation. J. Solid, 225: 309-312.
CrossRef  |  Direct Link  |  

Anitha, S. and B.D. Ranjitha Kumari, 2006. In vitro flowering in Rauvolfia tetraphylla L. Pak. J. Biol. Sci., 9: 422-424.
CrossRef  |  Direct Link  |  

Ansari, J.A. and N.N. Inamdar, 2010. The promise of traditional medicines. Int. J. Pharmacol., 6: 808-812.
CrossRef  |  Direct Link  |  

Ansari, J.A., S. Ali and M.A. Ansari, 2011. A brief focus on hepatoprotective leads from herbal origin. Int. J. Pharmacol., 7: 212-216.
CrossRef  |  Direct Link  |  

Appel, N., T. Schaller, F. Penin and R. Bartenschlager, 2006. From structure to function: New insights into hepatitis C virus RNA replication. J. Biol. Chem., 281: 9833-9836.
CrossRef  |  Direct Link  |  

Appidi, J.R., D.S. Grierson and A.J. Afolayan, 2008. Ethnobotanical study of plants used for the treatment of diarrhoea in the Eastern Cape, South Africa. Pak. J. Biol. Sci., 11: 1961-1963.
CrossRef  |  PubMed  |  Direct Link  |  

Arshad, M. and Q.A. Khan, 2000. Ethnobotanical study of some medicinal plants of Rawal town. Pak. J. Biol. Sci., 3: 1245-1246.
CrossRef  |  Direct Link  |  

Asano, J., K. Chiba, M. Tada and T. Yoshii, 1996. Antiviral activity of lignans and their glycosides from Justicia procumbens. Phytochemistry, 42: 713-717.
CrossRef  |  PubMed  |  Direct Link  |  

Badam, L., 1997. In vitro antiviral activity of indigenous glycyrrhizin, licorice and glycyrrhizic acid (Sigma) on Japanese encephalitis virus. J. Commun. Dis., 29: 91-99.
PubMed  |  Direct Link  |  

Badam, L., S.S. Bedekar, K.B. Sonawane and S.P. Joshi, 2002. In vitro antiviral activity of bael (Aegle marmelos Corr) upon human coxsackieviruses B1-B6. J. Commun. Dis., 34: 88-99.
PubMed  |  Direct Link  |  

Banerjee, A., A. Sinhababu, R.K. Kar and S. Mandal, 2004. Micromorphological studies of four fuel wood yielding tropical leguminous plants. Pak. J. Biol. Sci., 7: 100-104.
CrossRef  |  Direct Link  |  

Barakat, A.B., S.A. Shoman, N. Dina and O.R. Alfarouk, 2010. Antiviral activity and mode of action of Dianthus caryophyllus L. and Lupinus termes L. seed extracts against in vitro herpes simplex and hepatitis A viruses infection. J. Microbiol. Antimicrob., 2: 23-29.
Direct Link  |  

Barquero, A.A., L.E. Alche and C.E. Coto, 2004. Block of vesicular stomatitis virus endocytic and exocytic pathways by 1-cinnamoyl-3, 11-dihydroxymeliacarpin, a tetranortriterpenoid of natural origin. J. Gen. Virol., 85: 483-493.
CrossRef  |  Direct Link  |  

Bedows, E. and G.M. Hatfield, 1982. An investigation of the antiviral activity of Podophyllum peltatum. J. Nat. Prod., 45: 725-729.
CrossRef  |  Direct Link  |  

Behbahani, M., 2009. Anti-viral activity of the methanolic leaf extract of an Iranian medicinal plant Hyssopus officinalis against herpes simplex virus. J. Med. Plants Res., 3: 1118-1125.
Direct Link  |  

Bing, F.H., J. Liu, Z. Li, G.B. Zhang, Y.F. Liao, J. Li and C.Y. Dong, 2009. Anti-influenza-virus activity of total alkaloids from Commelina communis L. Arch. Virol., 154: 1837-1840.
CrossRef  |  Direct Link  |  

Binns, S.E., J. Hudson, S. Merali and J.T. Arnason, 2002. Antiviral activity of characterized extracts from Echinacea spp. (Heliantheae: Asteraceae) against Herpes simplex virus (HSV-I). Planta Med., 68: 780-783.
CrossRef  |  PubMed  |  Direct Link  |  

Biron, K.K., 2006. Antiviral drugs for cytomegalovirus diseases. Antiviral Res., 71: 154-163.
CrossRef  |  Direct Link  |  

Brandao, G.C., E.G. Kroon, J.R. dos Santos, J.R. Stehmann, J.A. Lombardi and A.B. de Oliveira, 2011. Antiviral activity of plants occurring in the State of Minas Gerais (Brazil): Part III. J. Chem. Pharm. Res., 3: 223-236.
Direct Link  |  

Breitbart, M. and F. Rohwer, 2005. Here a virus, there a virus, everywhere the same virus? Trends Micobiol., 13: 278-284.
CrossRef  |  Direct Link  |  

Briones, M.S., C.W. Dobard and S.A. Chow, 2010. Role of human immunodeficiency virus type 1 integrase in uncoating of the viral core. J. Virol., 84: 5181-5190.
CrossRef  |  

Bunyapraphatsara, N., S. Dechsree, C. Yoosook, A. Herunsalee and Y. Panpisutchai, 2000. Anti-herpes simplex virus component isolated from Maclura cochinchinensis. Phytomedicine, 6: 421-424.
Direct Link  |  

Burlone, M.E. and A. Budkowska, 2009. Hepatitis C virus cell entry: Role of lipoproteins and cellular receptors. J. Gen. Virol., 90: 1055-1070.
CrossRef  |  PubMed  |  Direct Link  |  

Cesar, G.Z., M.G. Alfonso, M.M. Marius, E.M. Elizabeth and C.B. Angel et al., 2011. Inhibition of HIV-1 reverse transcriptase, toxicological and chemical profile of Calophyllum brasiliense extracts from Chiapas, Mexico. Fitoterapia, 82: 1027-1034.
PubMed  |  

Chakraborty, D. and S. Chakraborti, 2010. Bioassay-guided isolation and identification of antibacterial and antifungal component from methanolic extract of green tea leaves (Camellia sinensis). Res. J. Phytochem., 4: 78-86.

Chen, J.L., P. Blanc, C.A. Stoddart, M. Bogan and E.J. Rozhon et al., 1998. New iridoids from the medicinal plant Barleria prionitis with potent activity against respiratory syncytial virus. J. Nat. Prod., 61: 1295-1297.
CrossRef  |  

Cheng, H.Y., C.M. Yang, T.C. Lin, L.T. Lin, L.C. Chiang and C.C. Lin, 2011. Excoecarianin, isolated from phyllanthus Urinaria linnea, inhibits herpes simplex virus type 2 infection through inactivation of viral particles. Evidence Based Compl. Alternative Med., 10.1093/ecam/nep157

Cheng, H.Y., T.C. Lin, K. Ishimaru, C.M. Yang, K.C. Wang and C.C. Lin, 2003. In vitro antiviral activity of prodelphinidin B-2 3,3-di-O-gallate from Myrica rubra. Planta Med., 69: 953-960.

Chiang, L.C., W. Chiang, M.C. Liu and C.C. Liu, 2003. In vitro antiviral activities of Caesalpinia pulcherrima and its related flavonoids. J. Antimicrob. Chemother., 50: 194-198.
CrossRef  |  Direct Link  |  

Corbett, E.L., C.J. Watt, N. Walker, D. Maher, B.G. Williams, M.C. Raviglione and C. Dye, 2003. The growing burden of tuberculosis: Global trends and interactions with the HIV epidemic. Arch. Intern. Med., 163: 1009-1021.
PubMed  |  

Craig, M.I., F. Benencia and F.C. Coulombie, 2001. Antiviral activity of an acidic polysaccharides fraction extracted from Cedrela tubiflora leaves Meliaceae plant. Fitoterapia, 72: 113-119.
CrossRef  |  Direct Link  |  

Czeizel, E. Andrew, Puho, Erzsebe, Acs, Nandor, Banhidy and Ferenc, 2006. A population based case-control study of oral moroxydine, an antiviral agent treatment during pregnancy. Int. J. Pharmacol., 2: 188-192.
CrossRef  |  Direct Link  |  

Davison, A.J., R. Eberle, B. Ehlers, G.S. Hayward and D.J. McGeoch et al., 2009. The order herpesvirales. Arch. Virol., 154: 171-177.
CrossRef  |  Direct Link  |  

Del Barrio, G. and F. Parra, 2000. Evaluation of the antiviral activity of an aqueous extract from Phyllanthus orbicularis. J. Ethnopharmacol., 72: 317-322.
CrossRef  |  

Denyer, C.V., P. Jackson, D.M. Loakes, M.R. Ellis and D.A. Young, 1994. Isolation of antirhinoviral sesquiterpenes from ginger (Zingiber officinale). J. Nat. Prod., 57: 658-662.
PubMed  |  

Duarte, M.E.R., D.G. Noseda, M.D. Noseda, S. Tulio, C.A. Pujol and E.B. Damonte, 2001. Inhibitory effect of sulfated galactans from the marine alga Bostrychia montagnei on herpes simplex virus replication in vitro. Phytomedicine, 8: 53-58.

Dupre, J. and M.A. O'Malley, 2009. Varieties of living things: Life at the intersection of lineage and metabolism. Philos. Theor. Biol., 1: 1-25.
Direct Link  |  

Edziri, H.L., G. Laurent, A. Mahjoub and M. Mastouri, 2011. Antiviral activity of Conyza canadensis (L.) Cronquist extracts grown in Tunisia. Afr. J. Biotechnol., 10: 9097-9100.
Direct Link  |  

Ehrhardt, C., E.R. Hrincius, V. Korte, I. Mazur and K. Droebner et al., 2007. A polyphenol rich plant extract, CYSTUS052, exerts anti influenza virus activity in cell culture without toxic side effects or the tendency to induce viral resistance. Antiviral Res., 76: 38-47.
PubMed  |  

Elkhalifa, K.F., I. Suliman and H. Assubki, 2005. Variations in tannin's contents of Acacia nilotica (L.) Willd. ex Del. in the Sudan. Pak. J. Biol. Sci., 8: 1021-1024.
CrossRef  |  Direct Link  |  

Emtehani, M.H. and M. Tabari, 2007. Acacia nilotica and Medicago sativa, suitable plants for agro-forestry in southern coasts of Iran. Pak. J. Biol. Sci., 10: 1713-1717.
CrossRef  |  PubMed  |  Direct Link  |  

Erdelmeier, C.A., J. Cinatl, H. Rabenau, H.W. Doerr, A. Biber and E. Koch, 1996. Antiviral and antiphlogistic activities of Hamamelis virginiana bark. Planta Med., 62: 241-245.

Esquenazi, D., M.D. Wigg, M.M. Miranda, H.M. Rodrigues and J.B. Tostes et al., 2002. Antimicrobial and antiviral activities of polyphenolics from Cocos nucifera Linn.(Palmae) husk fiber extract. Res. Microbiol., 153: 647-652.
CrossRef  |  Direct Link  |  

Falsey A.R., P.A. Hennessey, M.A. Formica, C. Cox and E.E. Walsh, 2005. Respiratory syncytial virus infection in elderly and high-risk adults. N. Engl. J. Med., 352: 1749-1759.
Direct Link  |  

Fang, E.F., P. Lin, J.H. Wong, S.W. Tsao and T.B. Ng, 2010. A lectin with anti-HIV-1 reverse transcriptase, antitumor and nitric oxide inducing activities from seeds of Phaseolus vulgaris cv. extralong autumn purple bean. J. Agric. Food Chem., 58: 2221-2229.
CrossRef  |  

Fard, M.H., S.L. Bodhankar and M. Dikshit, 2008. Cardioprotective activity of fruit of Lagenaria siceraria (Molina) standley on doxorubicin induced cardiotoxicity in rats. Int. J. Pharmacol., 4: 466-471.
CrossRef  |  Direct Link  |  

Farooq, K., A. Hameed, T. Javed, I. Ullah, A.W. Khan and H. Khan, 2006. Comparative immunological response of commercial oil based and liposomal vaccines of avian influenza H7. Pak. J. Biol. Sci., 9: 2402-2410.
CrossRef  |  Direct Link  |  

Firth, C., A. Kitchen, B. Shapiro, M.A. Suchard, E.C. Holmes and A. Rambaut, 2010. Using time-structured data to estimate evolutionary rates of double-stranded DNA viruses. Mol. Biol. Evol., 27: 2038-2051.
CrossRef  |  

Fokunang, C.N., J. Hitchcock, F. Spence, E.A. Tembe-Fokunang, J. Burkhardt, L. Levy and C. George, 2006. An overview of mitochondrial toxicity of nucleoside reverse transcriptase inhibitors associated with HIV therapy. Int. J. Pharmacol., 2: 152-162.
CrossRef  |  Direct Link  |  

Fuller, R.W., H.R. Bokesch, K.R. Gustafson, T.C. McKee and J.H. Cardellina et al., 1994. HIV-inhibitory coumarins from latex of the tropical rainforest tree Calophyllum teysmannii var. inophylloide. Bioorgan. Med. Chem. Lett., 4: 1961-1964.
CrossRef  |  

Gao, W. and J. Hu, 2007. Formation of hepatitis B virus covalently closed circular DNA: Removal of genome-linked protein. J. Virol., 81: 6164-6174.
CrossRef  |  Direct Link  |  

Garcia, G., L. Cavallaro, A. Broussalis, G. Ferraro and V. Martino et al., 1995. Antiviral activity of Achyrocline flaccida Wein DC aqueous extract. Phytother. Res., 9: 251-254.
CrossRef  |  

Geng, Y., P. Dalhaimer, S. Cai, R. Tsai, M. Tewari, T. Minko and D.E. Discher, 2007. Shape effects of filaments versus spherical particles in flow and drug delivery. Nat. Nanotechnol., 2: 249-255.
CrossRef  |  

Ghosh, S.C., S. Samsuzzaman, R. Sen, M.A.H. Talukder, S.M.A.H.M. Kamal and A.K. Saha, 2004. Effect of tree species and environment on the performance of wheat-T.aman rice and boro rice-t.aman rice cropping pattern. Pak. J. Biol. Sci., 7: 670-673.
CrossRef  |  Direct Link  |  

Gorbalenya, A.E., L. Enjuanes, J. Ziebuhr and E.J. Snijder, 2006. Nidovirales: Evolving the largest RNA virus genome. Virus Res., 117: 17-37.
PubMed  |  

Gupta, M., B.P. Shaw and A. Mukherjee, 2008. Evaluation of antipyretic effect of a traditional polyherbal preparation: A double-blind, randomized clinical trial. Int. J. Pharmacol., 4: 190-195.
CrossRef  |  Direct Link  |  

Gupta, M., B.P. Shaw and A. Mukherjee, 2008. Studies on antipyretic-analgesic and ulcerogenic activity of polyherbal preparation in rats and mice. Int. J. Pharmacol., 4: 88-94.
CrossRef  |  Direct Link  |  

Hall, H.I., R. Song, P. Rhodes, J. Prejean and Q. An et al., 2008. Estimation of HIV incidence in the United States. JAMA., 300: 520-529.
CrossRef  |  

Harvey, R.A., P.C. Champe, B.D. Fisher and W.A. Strohl, 2006. Lippincott's Illustrated Reviews: Microbiology. 2nd Edn., Lippincott Williams and Wilkins, Hagerstown, MD., ISBN: 9780781782159, pp: 354-366.

Hassan, S.W., F.L. Bilbis, M.J. Ladan, R.A. Umar and S.M. Dangoggo et al., 2006. Evaluation of antifungal activity and phytochemical analysis of leaves, roots and stem barks extracts of Calotropis procera (Asclepiadaceae). Pak. J. Biol. Sci., 9: 2624-2629.
CrossRef  |  Direct Link  |  

Hassani, A.S., N. Amirmozafari, N. Ordouzadeh, K. Hamdi, R. Nazari and A. Ghaemi, 2008. Volatile components of Camellia sinensis inhibit growth and biofilm formation of oral strepto. Pak. J. Biol. Sci., 11: 1336-1341.
CrossRef  |  PubMed  |  Direct Link  |  

Heneidy, S.Z. and L.M. Bidak, 2004. Potential uses of plant species of the coastal mediterranean region, Egypt. Pak. J. Biol. Sci., 7: 1010-1023.
CrossRef  |  

Hussein, E.A., A.M. Taj-Eldeen, A.S. Al-Zubairi, A.S. Elhakimi and A.R. Al-Dubaie, 2010. Phytochemical screening, total phenolics and antioxidant and antibacterial activities of callus from Brassica nigra L. hypocotyl explants. Int. J. Pharmacol., 6: 464-471.
CrossRef  |  Direct Link  |  

Hussein, G., H. Miyashiro, N. Nakamura, M. Hattori, N. Kakiuchi and K. Shimotohno, 2000. Inhibitory effects of sudanese medicinal plant extracts on hepatitis C virus (HCV) protease. Phytother. Res., 14: 510-516.
CrossRef  |  PubMed  |  Direct Link  |  

Ilboudo, D., D. Karou, W.M.C. Nadembega, A. Savadogo and O.D.S. Pignatelli et al., 2007. Prevalence of human herpes virus-8 and hepatitis B virus among HIV seropositive pregnant women enrolled in the mother-to-child HIV transmission prevention program at saint Camille medical centre in Burkina Faso. Pak. J. Biol. Sci., 10: 2831-2837.
CrossRef  |  PubMed  |  Direct Link  |  

Ishtiaq, M., W. Hanif, M.A. Khan, M. Ashraf and A.M. Butt, 2007. An ethnomedicinal survey and documentation of important medicinal folklore food phytonims of flora of Samahni valley (Azad Kashmir) Pakistan. Pak. J. Biol. Sci., 10: 2241-2256.
CrossRef  |  PubMed  |  Direct Link  |  

Jaffary, F., V. Musini, M.A. Nilforoushzadeh and K. Bassett, 2007. Systematic review of imiquimod for the treatment of external genital wart. Int. J. Pharmacol., 3: 1-10.
CrossRef  |  Direct Link  |  

Javed, T., U.A. Ashfaq, S. Riaz, S. Rehman and S. Riazuddin, 2011. In-vitro antiviral activity of Solanum nigrum against hepatitis C virus. Virol. J., Vol. 8, 10.1186/1743-422X-8-26

Joseph, B. and S.J. Raj, 2011. An overview: Pharmacognostic properties of Phyllanthus amarus Linn. Int. J. Pharmacol., 7: 40-45.
CrossRef  |  Direct Link  |  

Jun, T., Z. Liancai and W. Bochu, 2007. Effect of ginsenosides on malondialdehyde, nitric oxide and endothelin-1 production in vascular endothelial cells suffering from lipid peroxidation injury. Int. J. Pharmacol., 3: 101-105.
CrossRef  |  Direct Link  |  

Kageyama, S., M. Kurokawa, H. Sato, T. Yukawa, H. Ohyama, T. Kurimura, T. Namba and K. Shiraki, 1996. Potent activity of the extract of Geum japonicum Thunb. For the prophylaxis of cytomegalovirus infection in AIDS patients. Int. Conf. AIDS, 11: 65-65.
Direct Link  |  

Kagone, T.S., H. Hien, N. Meda, P.S. Diagbouga and A. Sawadogo et al., 2011. Characterization of HIV-1 genotypes and antiretroviral drug-resistance mutations among patients in Burkina Faso. Pak. J. Biol. Sci., 14: 392-398.
CrossRef  |  

Kalus, U., A. Grigorov, O. Kadecki, J.P. Jansen, H. Kiesewetter and H. Radtke, 2009. Cistus incanus (CYSTUS052) for treating patients with infection of the upper respiratory tract: A prospective, randomised, placebo-controlled clinical study. Antiviral Res., 84: 267-271.
CrossRef  |  PubMed  |  Direct Link  |  

Kan, A., B. Ozcelik and M. Kartal, 2009. In vitro antiviral activities under cytotoxic doses against herpes simplex type-1 and parainfluensa-3 viruses of Cicer arietinum L. (chickpea). Afr. J. Phar. Pharmacol., 3: 627-631.
Direct Link  |  

Karou, S.D., T. Tchacondo, D.P. Ilboudo and J. Simpore, 2011. Sub-saharan rubiaceae: A review of their traditional uses, phytochemistry and biological activities. Pak. J. Biol. Sci., 14: 149-169.
CrossRef  |  Direct Link  |  

Kaur, C.D. and S. Saraf, 2011. Photochemoprotective activity of alcoholic extract of Camellia sinensis. Int. J. Pharmacol., 7: 400-404.
CrossRef  |  Direct Link  |  

Kernan, M.R., A. Amarquaye, J.L. Chen, J. Chan and D.F. Sesin et al., 1998. Antiviral phenylpropanoid glycosides from the medicinal plant Markhamia lutea. J. Nat. Prod., 61: 564-570.
CrossRef  |  PubMed  |  Direct Link  |  

Kernan, M.R., A. Sendl, J.L. Chen, S.D. Jolad and P. Blanc et al., 1997. Two new lignans with activity against influenza virus from the medicinal plant Rhinacanthus nasutus. J. Natural Product, 60: 635-637.

Kim, H.K., H.K. Lee, C.G. Shin and H. Huh, 1999. HIV integrase inhibitory activity of Agastache rugosa. Arch. Pharm. Res., 22: 520-523.
CrossRef  |  PubMed  |  

Krishnan, N., S. Ramanathan, S. Sasidharan, V. Murugaiyah and S.M. Mansor, 2010. Antimicrobial activity evaluation of Cassia spectabilis leaf extracts. Int. J. Pharmacol., 6: 510-514.
CrossRef  |  Direct Link  |  

Kumar, G., G.S. Banu, A.G. Murugesan and M.R. Pandian, 2007. Preliminary toxicity and phytochemical studies of aqueous bark extract of Helicteres isora L. Int. J. Pharmacol., 3: 96-100.
CrossRef  |  Direct Link  |  

Kurokawa, M., P. Basnet, M. Ohsugi, T. Hozumi and S. Kadota et al., 1999. Anti-herpes simplex virus activity of moronic acid purified from Rhus javanica in vitro and in vivo. J. Pharmacol. Exp. Ther., 289: 72-78.
Direct Link  |  

Ky, J.M.K., P. Zerbo, C. Gnoula, J. Simpore, J.B. Nikiema and J. Millogo-Rasolodimby, 2009. Medicinal plants used in traditional medicine in the centre east region of burkina faso. Pak. J. Biol. Sci., 12: 1287-1298.
CrossRef  |  Direct Link  |  

Laure, F., P. Raharivelomanana, J.F. Butaud, J.P. Bianchini and E.M. Gaydou, 2008. Screening of anti-HIV-1 inophyllums by HPLC-DAD of Calophyllum inophyllum leaf extracts from French Polynesia Islands. Anal. Chim. Acta, 624: 147-153.
CrossRef  |  Direct Link  |  

Lazzari I.S. and K. Stohr, 2004. Avian influenza and influenza pandemics. Bull. World Health Organ., 82: 242-242.
PubMed  |  

Lee, D., K.H. Boo, J.K. Woo, F. Duan and K.H. Lee et al., 2011. Anti-bacterial and anti-viral activities of extracts from Terminalia chebula Bark. J. Korean Soc. Appl. Biol. Chem., 54: 295-298.

Lee-Huang, S., P.L. Huang, H.F. Kung, B.Q. Li and P.L. Huang et al., 1991. TAP 29: An anti-human immunodeficiency virus protein from Trichosanthes kirilowii that is nontoxic to intact cells. PNAS, 88: 6570-6574.
Direct Link  |  

Lee-Huang, S., P.L. Huangi, P.L. Huang, A.S. Bourinbaiar, H.C. Chens and H.F. Kungii, 1995. Inhibition of the integrase of Human Immunodeficiency Virus (HIV) type 1 by anti-HIV plant proteins MAP30 and GAP31. Proc. Natl. Acad. Sci. USA., 92: 8818-8822.
Direct Link  |  

Li, Y., P.P. But and V.E. Ooi, 2005. Antiviral activity and mode of action of caffeoylquinic acids from Schefflera heptaphylla (L.) Frodin. Antiviral Res., 68: 1-9.

Lin, Y.M., H. Anderson, M.T. Flavin, Y.H. Pai and E. Mata-Greenwood et al., 1997. In vitro anti-HIV activity of biflavonoids isolated from Rhus succedanea and Garcinia multiflora. J. Nat. Prod., 60: 884-888.
CrossRef  |  Direct Link  |  

Lowen, A.C., S. Mubareka, J. Steel and P. Palese, 2007. Influenza virus transmission is dependent on relative humidity and temperature. PLoS Pathog, 3: 1470-1476.

Lu, S.Y., Y.J. Qiao, P.G. Xiao and X.H. Tan, 2005. Identification of antiviral activity of Toddalia asiatica (L.) against influenza type A virus. Zhongguo Zhong Yao Za Zhi., 30: 998-1001.
PubMed  |  

Ma, S.C., P.P. But, V.E. Ooi, Y.H. He, S.H. Lee, S.F. Lee and R.C. Lin, 2001. Antiviral amentoflavone from Selaginella sinensis. Biol. Pharm. Bull., 24: 311-312.
CrossRef  |  PubMed  |  Direct Link  |  

Mahalakshmi, R., P. Rajesh, N. Ramesh, V. Balasubramanian and V.R. Kannan, 2010. Hepatoprotective activity on Vitex negundo Linn. (verbenaceae) by using wistar albino rats in ibuprofen induced model. Int. J. Pharmacol., 6: 658-663.
CrossRef  |  Direct Link  |  

Mahzounieh, M., E. Moghtadaei and T. Zahraei Salehi, 2006. Detection of calicivirus genome in calves using Ni/E3 primers in Shahrekord area, Iran. Pak. J. Biol. Sci., 9: 227-230.
CrossRef  |  Direct Link  |  

Makambila-Koubemba, M.C., B. Mbatchi, D. Ardid, A. Gelot and C. Henrion et al., 2011. Pharmacological studies of ten medicinal plants used for analgesic purposes in congo brazzaville. Int. J. Pharmacol., 7: 608-615.
CrossRef  |  

Marchetti, M., S. Pisani, V. Pietropaolo, L. Seganti, R. Nicoletti, A. Degener and N. Orsi, 1996. Antiviral effect of a polysaccharide from Sclerotium glucanicum towards herpes simplex virus type 1 infection. Planta Med., 62: 303-307.
PubMed  |  

Mbaya, A.W. and U.I. Ibrahim, 2011. In vivo and in vitro activities of medicinal plants on haemic and humoral trypanosomes: A review. Int. J. Pharmacol., 7: 1-11.
CrossRef  |  Direct Link  |  

Meragelman, K.M., T.C. McKee and M.R. Boyd, 2001. Anti-HIV prenylated flavonoids from Monotes africanus. J. Nat. Prod., 64: 546-548.
PubMed  |  

Meyer, J.J.M., A.J. Afolayan, M.B. Taylor and D. Erasmus, 1997. Antiviral activity of galangin isolated from the aerial parts of Helichrysum aureonitens. J. Ethnopharmacol., 56: 165-169.
CrossRef  |  Direct Link  |  

Miladi, S., N. Abid, C. Debarnot, M. Damak, B. Canard, M. Aouni and B. Selmi, 2011. In vitro antiviral activities of extracts derived from Daucus maritimus seeds. Natural Product Res., 10.1080/14786419.2010.550263

Mohamed, A.M. and N.S. Metwally, 2009. Antiaflatoxigenic activities of some plant aqueous extracts against aflatoxin-b1 induced renal and cardiac damage. J. Pharmacol. Toxicol., 4: 1-16.
CrossRef  |  Direct Link  |  

Mohapatra, S.S. and S. Boyapalle, 2008. Epidemiologic, experimental and clinical links between respiratory syncytial virus infection and asthma. Clin. Microbiol. Rev., 21: 495-504.
PubMed  |  

Momtaz, S. and M. Abdollahi, 2010. An update on pharmacology of Satureja species; From antioxidant, antimicrobial, antidiabetes and anti-hyperlipidemic to reproductive stimulation. Int. J. Pharmacol., 6: 346-353.
CrossRef  |  Direct Link  |  

Moundipa, P.F., S. Ngouela, G.A. Tchamba, N.F. Njayou, P.D.D. Chuisseu, F. Zelefack and E. Tsamo, 2007. Antihepatotoxic activity of Xylopia phloiodora extracts on some experimental models of liver injury in rats. Int. J. Pharmacol., 3: 74-79.
CrossRef  |  Direct Link  |  

Nagai, T., Y. Suzuki, T. Tomimori and H. Yamada, 1995. Antiviral activity of plant flavonoid, 5,7,4'-trihydroxy-8-methoxyflavone, from the roots of Scutellaria baicalensis against influenza A (H3N2) and B viruses. Biol. Pharm. Bull., 18: 295-299.
PubMed  |  

Ndjonka, D., C. Agyare, K. Luersen, A. Hensel and E. Liebau, 2010. In vitro anti-leishmanial activity of traditional medicinal plants from cameroon and Ghana. Int. J. Pharmacol., 6: 863-871.
CrossRef  |  Direct Link  |  

Ng, T.B. and H. Wang, 2001. Panaxagin, a new protein from Chinese ginseng possesses anti-fungal, anti-viral, translation-inhibiting and ribonuclease activities. Life Sci., 68: 739-749.
PubMed  |  

Obaid, A.Y., O.A. Abu-Zinadah and H.K. Hussein, 2011. The beneficial effects of green tea extract and its main derivatives in repairing skin burns of rabbit. Int. J. Biol. Chem., 5: 103-115.
CrossRef  |  Direct Link  |  

Oguntibeju, O.O., W.M.J Van den Heever and F.E. Van Schalkwyk, 2007. Supplementation effect on body weight and BMI of HIV-positive/AIDS patients. Int. J. Pharmacol., 3: 120-122.
CrossRef  |  Direct Link  |  

Oh, C., J. Price, M.A. Brindley, M.P. Widrlechner and L. Qu et al., 2011. Inhibition of HIV-1 infection by aqueous extracts of Prunella vulgaris L. Virol. J., 8: 188-188.
PubMed  |  Direct Link  |  

Ojha, S.K., M. Nandave, S. Arora, R. Narang, A.K. Dinda and D.S. Arya, 2008. Chronic administration of Tribulus terrestris Linn. extract improves cardiac function and attenuates myocardial infarction in rats. Int. J. Pharmacol., 4: 1-10.
CrossRef  |  Direct Link  |  

Oldstone, M.B., 1993. Rous-whipple award lecture. viruses and diseases of the twenty-first century. Am. J. Pathol., 143: 1241-1249.
PubMed  |  Direct Link  |  

Onwuliri, V.A. and G.E. Anekwe, 2001. Amino acids and other biochemical components of Ricinus communis (Variety Minor), an anti-conceptive seed. Pak. J. Biol. Sci., 4: 866-868.
CrossRef  |  Direct Link  |  

Ooi, L.S., W.S. Ho, K.L. Ngai, L. Tian, P.K. Chan, S.S. Sun and V.E. Ooi, 2010. Narcissus tazetta lectin shows strong inhibitory effects against respiratory syncytial virus, influenza A (H1N1, H3N2, H5N1) and B viruses. J. Biosci., 35: 95-103.
PubMed  |  Direct Link  |  

Ooi, L.S.M., S.S.M. Sun and V.E.C. Ooi, 2004. Purification and characterization of a new antiviral protein from the leaves of Pandanus amaryllifolius (Pandanaceae). Int. J. Biochem. Cell. Biol., 36: 1440-1446.
CrossRef  |  

Parida, M.M., C. Upadhyay, G. Pandya and A.M. Jana, 2002. Inhibitory potential of neem (Azadirachta indica Juss) leaves on Dengue virus type-2 replication. J. Ethnopharmacol., 79: 273-278.
PubMed  |  

Patton, G.C., C. Coffey, S.M. Sawyer, R.M. Viner and D.M. Haller et al., 2009. Global patterns of mortality in young people: A systematic analysis of population health data. The Lancet, 374: 881-892.
PubMed  |  Direct Link  |  

Pervez, K., 2000. Effect of combination chemotherapy on hepatitis C virus in hepatic patients. Pak. J. Biol. Sci., 3: 969-970.
CrossRef  |  Direct Link  |  

Pervez, K., 2000. Hepatitis C virus core protein expression for enzyme linked immunosorbant assay. Pak. J. Biol. Sci., 3: 1096-1097.
CrossRef  |  Direct Link  |  

Pichereau, C., K. Desseaux, A. Janin, C. Scieux and R.P. de Latour et al., 2011. The complex relationship between human herpesvirus 6 and acute graft-versus-host disease. Biol. Blood Marrow Transplant., 10.1016/j.bbmt.2011.07.018

Pichlmair, A., O. Schulz, C.P. Tan, T.I. Naslund, P. Liljestrom, F. Weber and C. Reis e Sousa, 2006. RIG-I-mediated antiviral responses to single-stranded RNA bearing 5'-phosphates. Science, 314: 997-1001.
PubMed  |  

Pleschka, S., M. Stein, R. Schoop and J.B. Hudson, 2009. Anti-viral properties and mode of action of standardized Echinacea purpurea extract against highly pathogenic avian Influenza virus (H5N1, H7N7) and swine-origin H1N1 (S-OIV). Virol. J., 6: 197-197.
CrossRef  |  PubMed  |  Direct Link  |  

Praseno, S.S. and N. Rintiswati, 1997. Antiviral activity of Momordica charantia: A preliminary study on in vitro anti-herpes simplex virus. Periodic Med. Sci., 29: 121-123.

Premanathan, M., K. Kathiresan, N. Yamamoto and H. Nakashima, 1999. In vitro anti-human immunodeficiency virus activity of polysaccharide from Rhizophora mucronata Poir. Biosci. Biotechnol. Biochem., 63: 1187-1191.
PubMed  |  

Premanathan, M., R. Araakik, H. Izumi, K. Kathiresan, M. Nakano, N. Yamamoto and H. Nakashima, 1999. Antiviral properties of a mangrove plant, Rhizophora apiculata Blume, against human immunodeficiency virus. Antiviral Res., 15: 113-122.
CrossRef  |  Direct Link  |  

Pu, J.X., L.M. Yang, W.L. Xiaoa, R.T. Li and C. Lei et al., 2008. Compounds from Kadsura heteroclite and related anti-HIV activity. Phytochemistry, 69: 1266-1272.
CrossRef  |  Direct Link  |  

Qureshi, S.A., A. Nawaz, S.K. Udani and B. Azmi, 2009. Hypoglycaemic and Hypolipidemic activities of Rauwolfia serpentina in Alloxan-induce diabetic rats. Int. J. Pharmacol., 5: 323-326.
CrossRef  |  

Qureshi, S.J., S. Bano, T. Mohammad and M.A. Khan, 2001. Medicinal potential of poisonous plants of tehsil Kahuta from district Rawalpindi, Pakistan. Pak. J. Biol. Sci., 4: 331-332.
CrossRef  |  Direct Link  |  

Rahman, S., M.M. Akbor, A. Howlader and A. Jabbar, 2009. Antimicrobial and cytotoxic activity of the alkaloids of amlaki (Emblica officinalis). Pak. J. Biol. Sci., 12: 1152-1155.
CrossRef  |  PubMed  |  Direct Link  |  

Raja, K.S. Q. Wang and M.G. Finn, 2003. Icosahedral virus particles as polyvalent carbohydrate display platforms. Chembiochem, 42: 1348-1351.
PubMed  |  Direct Link  |  

Rajbhandari, M., R. Mente, P.K. Jha, R.P. Chaudhary and S. Bhattarai et al., 2009. Antiviral activity of some plants used in Nepalese traditional medicine. Evidence-Based Complement. Alternat. Med., 63: 517-522.
Direct Link  |  

Rehman, S., U.A. Ashfaq, S. Riaz, T. Javed and S. Riazuddin, 2011. Antiviral activity of Acacia nilotica against Hepatitis C Virus in liver infected cells. Virol. J., 86: 220-220.
CrossRef  |  Direct Link  |  

Reichling, J., A. Neuner, M. Sharaf, M. Harkenthal and P. Schnitzler, 2009. Antiviral activity of Rhus aromatica (fragrant sumac) extract against two types of herpes simplex viruses in cell culture. Pharmazie, 64: 538-541.
Direct Link  |  

Reutrakul, V., N. Ningnuek, M. Pohmakotr, C. Yoosook and C. Napaswad et al., 2007. Anti HIV-1 flavonoid glycosides from Ochna integerrima. Planta Med., 73: 683-688.
PubMed  |  

Richardson, T.H., 2010. Cannabis use and mental health: A review of recent epidemiological research. Int. J. Pharmacol., 6: 796-807.
CrossRef  |  Direct Link  |  

Rocha Martins, L.R., M.A. Brenzan, C.V. Nakamura, B.P. Dias Filho, T.U. Nakamura, L.E. Ranieri Cortez and DA. Garcia Cortez, 2011. In vitro antiviral activity from Acanthospermum australe on herpesvirus and poliovirus. Pharm Biol., 49: 26-31.
PubMed  |  Direct Link  |  

Roja, G. and M.R. Heble, 1995. Castanospermine, an HIV inhibitor from tissue cultures of Castanospermum australe. Phytotherapy Res., 9: 540-542.
CrossRef  |  Direct Link  |  

Roner, M.R., J. Sprayberry, M. Spinks and S. Dhanji, 2007. Antiviral activity obtained from aqueous extracts of the Chilean soapbark tree (Quillaja saponaria Molina). J. Gen. Virol., 88: 275-285.
CrossRef  |  Direct Link  |  

Roshandel, G., S. Semnani, N. Abdolahi, A.A. Keshtkar and S. Besharat et al., 2007. Prevalence of hepatitis D virus infection in HBsAg positive subjects in Iran. Pak. J. Biol. Sci., 10: 1751-1754.
CrossRef  |  PubMed  |  Direct Link  |  

Saeed, S.A. and A. Hussain, 2006. Anti-HIV drugs of the herbal type. DAWN Sci-tech World, http://archives.dawn.com/dawnftp/72.249.57.55/dawnftp/weekly/science/archive/060603/science5.htm.

Sampathkumar, P., B. Dheeba, V. Vidhyasagar, T. Arulprakash and R. Vinothkannan, 2008. Potential antimicrobial activity of various extracts of Bacopa monnieri (Linn.). Int. J. Pharmacol., 4: 230-232.
CrossRef  |  Direct Link  |  

Selisko, B., J.C. Guillemot, K. Alvarez and B. Canard, 2007. Opportunities in the development of anti-dengue drugs. Annual report , Scientific working group report on dengue, TDR.

Semalty, M., A. Semalty, G.P. Joshi and M.S.M. Rawat, 2010. In vivo hair growth activity of herbal formulations. Int. J. Pharmacol., 6: 53-57.
CrossRef  |  Direct Link  |  

Semple, S.J., S.F. Nobbs, S.M. Pyke, G.D. Reynolds and R.L. Flower, 1999. Antiviral flavonoid from Pterocaulon sphacelatum, an australian aboriginal medicine. J. Ethnopharmacol., 68: 283-288.
CrossRef  |  

Sendl, A., J.L. Chen, S.D. Jolad, C. Stoddart and E. Rozhon et al., 1996. Two new naphthoquinones with antiviral activity from Rhinacanthus nasutus. J. Nat. Prod., 59: 808-811.
CrossRef  |  

Serkedjieva, J., 1996. A polyphenolic extract from Geranium sanguineum L. inhibits influenza virus protein expression. Phytotherapy Res., 10: 441-443.
CrossRef  |  

Serkedjieva, J., N. Manolova, I. Zgorniak-Nowosielska, B. Zawilinska and J. Grzybek, 2006. Antiviral activity of the infusion (SHS-174) from flowers of Sambucus nigra L., aerial parts of Hypericum perforatum L. and roots of Saponaria officinalis L., against influenza and herpes simplex viruses. Phytother. Res., 4: 97-100.
CrossRef  |  

Shalaby, E.A., S.M.M. Shanab and V. Singh, 2010. Salt stress enhancement of antioxidant and antiviral efficiency of Spirulina platensis. J. Med. Plants Res., 4: 2622-2632.
Direct Link  |  

Shin, W.J., K.H. Lee, M.H. Park and B.L. Seong, 2010. Broad-spectrum antiviral effect of Agrimonia pilosa extract on influenza viruses. Microbiol. Immunol., 54: 11-19.
CrossRef  |  PubMed  |  Direct Link  |  

Shinde, S.L., S.B. Junne, S.S. Wadje and M.M.V. Baig, 2009. The diversity of antibacterialcompounds of terminalia species (Combretaceae). Pak. J. Biol. Sci., 12: 1483-1486.
PubMed  |  

Shinwari, M.I. and M.A. Khan, 2000. Vegetation comparison of sacred, reserved and unreserved sites of Rumli village at Margalla Hills National Park, Islamabad. Pak. J. Biol. Sci., 3: 1681-1683.
CrossRef  |  Direct Link  |  

Shirazi, M.U., B. Khanzada, S.M. Alam, R. Ansari, S.M. Mujtaba, M. Ali, M. Ali and M.A. Khan, 2001. Seasonal nutrient variations in two Acacia species growing under saline environment. Pak. J. Biol. Sci., 4: 514-517.
CrossRef  |  Direct Link  |  

Shokrzadeh, M., A.G. Ebadi, S.S. Mirshafiee and M.I. Choudhary, 2006. Effect of the aqueous green leaf extract of green tea (Camellia sinensis) on glucose level of rat. Pak. J. Biol. Sci., 9: 2708-2711.
CrossRef  |  Direct Link  |  

Sluis-Cremer, N. and G. Tachedjian, 2008. Mechanisms of inhibition of HIV replication by nonnucleoside reverse transcriptase inhibitors. Virus Res., 134: 147-156.
Direct Link  |  

Sokmen, M., M. Angelova, E. Krumova, S. Pashova, S. Ivancheva, A. Sokmen and A. Serkedjieva, 2005. In vitro antioxidant activity of polyphenol extracts with antiviral properties from Geranium sanguineum L. Life Sci., 76: 2981-2993.
PubMed  |  

Soleimanjahi, H., M. Jamalidoost, F. Fotouhi and Z. Meshkat, 2007. Amplification and cloning of herpes simplex virus type 2 glycoprotein G from an Iranian isolate. Pak. J. Biol. Sci., 10: 955-958.
CrossRef  |  PubMed  |  Direct Link  |  

Song, J.H., K.J. Im, S.W. Chae and H.J. Choi, 2010. Prunus mume possess anti-human rhinovirus activit. J. Cosmet. Publ. Health, 6: 1-3.
Direct Link  |  

Song, J.M., K.H. Lee and B.L. Seong, 2005. Antiviral effect of catechins in green tea on influenza virus. Antiviral Res., 68: 66-74.
CrossRef  |  PubMed  |  Direct Link  |  

Sonibare, M.A., T.O. Lawal and O.O. Ayodeji, 2011. Antimicrobial evaluation of plants commonly used in the management of psychosis opportunistic infections. Int. J. Pharmacol., 7: 492-497.
CrossRef  |  

Sotanaphun, U., V. Lipipun, R. Suttisri and R. Bavovada, 1999. A new antiviral and antimicrobial sesquiterpene from Glyptopetalum sclerocarpum. Planta Med., 65: 257-258.
PubMed  |  

Subash, K.R., K.S. Ramesh, B.V. Charian, F. Britto, N.J. Rao and S. Vijaykumar, 2011. Study of hepatoprotective activity of Solanum nigrum and Cichorium intybus. Int. J. Pharmacol., 7: 504-509.
CrossRef  |  

Subbarao, K. and T. Joseph, 2007. Scientific barriers to developing vaccines against avian influenza viruses. Nat. Rev. Immunol., 7: 267-278.
CrossRef  |  

Sukandar, E.Y., H. Permana, I.K. Adnyana, J.I. Sigit, R.A. Ilyas, P. Hasimun and D. Mardiyah, 2010. Clinical study of turmeric (Curcuma longa L.) and garlic (Allium sativum L.) extracts as antihyperglycemic and antihyperlipidemic agent in type-2 diabetes-dyslipidemia patients. Int. J. Pharmacol., 6: 456-463.
CrossRef  |  Direct Link  |  

Sunday, O.A., A.B. Munir, O.O. Akeeb, A.A. Bolanle and S.O. Badaru, 2010. Antiviral effect of Hibiscus sabdariffa and Celosia argentea on measles virus. Afr. J. Microbiol. Res., 4: 293-296.
Direct Link  |  

Suttle, C.A., 2005. Viruses in the sea. Nature, 437: 356-361.
CrossRef  |  

Sydiskis, R.J., D.G. Owen, J.L. Lohr, K.H. Rosler and R.N. Blomster, 1991. Inactivation of enveloped viruses by anthraquinones extracted from plants. Antimicrob. Agents Chemother., 35: 2463-2466.
PubMed  |  Direct Link  |  

Syed, G.H., Y. Amako and A. Siddiqui, 2010. Hepatitis C virus hijacks host lipid metabolism. Trends Endocrinol. Metab., 21: 33-40.
CrossRef  |  PubMed  |  

Sylvestre, D.L., B.J. Clements and Y. Malibu, 2006. Cannabis use improves retention and virological outcomes in patients treated for hepatitis C. Eur. J. Gastroenterol. Hepatol., 18: 1057-1063.
Direct Link  |  

Tabassum, F., R. Khurshid and M.W. Akhtar, 2000. Identification of marker protein, in patient with chronic liver disease. Pak. J. Biol. Sci., 3: 1509-1510.
CrossRef  |  Direct Link  |  

Takechi M. and Tanaka Y., 1981. Purification and characterization of antiviral substance from the bud of Syzygium aromatica. Planta Med., 42: 69-74.
PubMed  |  

Tehranipour, M. and S. Ebrahimpour, 2009. Evaluating the effect of aquatic extract of Cannabis sativa seed on spatial memory consolidation in rats. J. Biol. Sciences, 9: 884-888.
CrossRef  |  Direct Link  |  

Thompson, W.W., D.K. Shay, E. Weintraub, L. Brammer, C.B. Bridges, N.J. Cox and K. Fukuda, 2004. Influenza-associated hospitalizations in the United States. JAMA, 292: 1333-1340.
PubMed  |  

Trento, A., I. Casas, A. Calderon, M.L. Garcia-Garcia, C. Calvo, P. Perez-Brena and J.A. Melero, 2010. Ten years of global evolution of the human respiratory syncytial virus BA genotype with a 60-nucleotide duplication in the G protein gene. J. Virol., 84: 7500-7512.
CrossRef  |  

Valcheva-Kuzmanova, S.V. and A. Belcheva, 2006. Current knowledge of Aronia melanocarpa as a medicinal plant. Folia Med. (Plovdiv), 48: 11-17.
PubMed  |  

Vimalanathan, S., L. Kang, V.T. Amiguet, J. Livesey, J.T. Arnason and J. Hudson, 2005. Echinacea purpurea aerial parts contain multiple antiviral compounds. Pharm. Biol., 43: 740-745.
Direct Link  |  

Vimalanathan, S., S. Ignacimuthu and J.B. Hudson, 2009. Medicinal plants of Tamil Nadu (Southern India) are a rich source of antiviral activities. Pharm. Biol., 47: 422-429.
Direct Link  |  

WHO, 2001. Herpes simplex virus type 2: Programmatic and research priorities in developing countries. Report of a WHO/UNAIDS/LSHTM Workshop | London, UK. http://www.who.int/hiv/pub/sti/pub9/en/index.html.

WHO, 2011. Hepatitis C. Fact sheet N°164. http://www.who.int/mediacentre/factsheets/fs164/en/.

WHO, 2011. World Health Statistics. WHO, Geneva, Switzerland..

Wang, H.X. and T.B. Ng, 2001. Examination of lectins, polysaccharopeptide, polysaccharide, alkaloid, coumarin and trypsin inhibitors for inhibitory activity against human immunodeficiency virus reverse transcriptase and glycohydrolases. Planta Med., 67: 669-672.
PubMed  |  

Wapling, J., S. Srivastava, M. Shehu-Xhilaga and G. Tachedjian, 2007. Targeting human immunodeficiency virus type 1 assembly, maturation and budding. Drug Target Insights, 2: 159-182.
Direct Link  |  

Weber, N.D., D.O. Andersen, J.A. North, B.K. Murray, L.D. Lawson and B.G. Hughes, 1992. In vitro virucidal effects of Allium sativum (garlic) extract and compounds. Planta Med., 58: 417-423.
CrossRef  |  PubMed  |  Direct Link  |  

Wiart, C., K. Kumar, M.Y. Yusof, H. Hamimah, Z.M. Fauzi and M. Sulaiman, 2005. Antiviral properties of ent-labdene diterpenes of Andrographis paniculata Nees, inhibitors of herpes simplex virus type 1. Phytother. Res., 19: 1069-1070.
CrossRef  |  

Wirotesangthong, M., T. Nagai, H. Yamada, S. Amnuoypol and C. Mungmee, 2009. Effects of Clinacanthus siamensis leaf extract on influenza virus infection. Microbiol. Immunol., 53: 66-74.
PubMed  |  

Yang, C.M., H.Y. Cheng, T.C. Lin, L.C. Chiang and C.C. Lin, 2007. Hippomanin a from acetone extract of Phyllanthus urinaria inhibited HSV-2 but not HSV-1 infection in vitro. Phytother. Res., 21: 1182-1186.
CrossRef  |  

Ye, X.Y. and T.B. Ng, 2001. Isolation of unguilin, a cyclophilin-like protein with anti-mitogenic, antiviral and antifungal activities, from black-eyed pea. J. Protein Chem., 20: 353-359.
CrossRef  |  

Ye, X.Y., H.X. Wang and T.B. Ng, 2000. Structurally dissimilar proteins with antiviral and antifungal potency from cowpea (Vigna unguiculata) seeds. Life Sci., 67: 3199-3207.
CrossRef  |  

Ye, X.Y., T.B. Ng, P.W.K. Tsang and J. Wang, 2001. Isolation of a homodimeric lectin with antifungal and antiviral activities from red kidney bean (Phaseolus vulgaris) seeds. J. Protein Chem., 20: 367-375.
CrossRef  |  Direct Link  |  

Yeh, J.H., H.F. Chiu, J.S. Wang, J.K. Lee and T.C. Chou, 2010. Protective effect of baicalein extracted from Scutellaria baicalensis against lipopolysaccharide-induced glomerulonephritis in mice. Int. J. Pharmacol., 6: 81-88.
CrossRef  |  Direct Link  |  

Yoshida, T., H. Ito, T. Hatano, M. Kurata and T. Nakanishi et al., 1996. New hydrolyzable tannins, shephagenins A and B, from Shepherdia argentea as HIV-1 reverse transcriptase inhibitors. Chem. Pharm. Bull. (Tokyo), 44: 1436-1439.
PubMed  |  

Yucharoen, R., S. Anuchapreeda and Y. Tragoolpua, 2011. Anti-herpes simplex virus activity of extracts from the culinary herbs Ocimum sanctum L., Ocimum basilicum L. and Ocimum americanum L. Afr. J. Biotechnol., 10: 860-866.
Direct Link  |  

Zakizad, M., F. Salmeh, T. Yaghoobi, M. Yaghoubian and M.B. Nesami et al., 2009. Seroprevalence of hepatitis C infection and associated risk factors among addicted prisoners in Sari-Iran. Pak. J. Biol. Sci., 12: 1012-1018.
CrossRef  |  PubMed  |  Direct Link  |  

Zambon, M.C., 2001. The pathogenesis of influenza in humans. Rev. Med. Virol., 11: 227-241.
Direct Link  |  

Zandi, K., M.A. Zadeh, K. Sartavi and Z. Rastian, 2007. Antiviral activity of Aloe vera against herpes simplex virus type 2: An in vitro study. Afr. J. Biotechnol., 6: 1770-1773.
Direct Link  |  

Zhang, J., B. Zhan, X. Yao, Y. Gao and J. Shong, 1995. Antiviral activity of tannin from the pericarp of Punica granatum L. against genital herpes virus in vitro. Zhongguo Zhong Yao Za Zhi, 20: 556-558, (In Chinese).
PubMed  |  Direct Link  |  

Zhang, Y., H. Zhu, G. Ye, C. Huang and Y. Yang et al., 2006. Antiviral effects of sophoridine against coxsackievirus B3 and its pharmacokinetics in rats. Life Sci., 78: 1998-2005.
CrossRef  |  

Zhong, Y., C. Zuo, F. Li, X. Ding and Q. Yao et al., 1998. Chemical constituents of Phyllanthus urinaria L. and its antiviral activity against hepatitis B virus. Zhongguo Zhong Yao Za Zhi., 23: 363-364.
PubMed  |  

Ziyaeyan, M., A. Japoni, M.H. Roostaee, S. Salehi and H. Soleimanjahi, 2007. A serological survey of herpes simplex virus type 1 and 2 Immunity in pregnant women at labor stage in Tehran, Iran. Pak. J. Biol. Sci., 10: 148-151.
CrossRef  |  PubMed  |  Direct Link  |  

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