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Phytochemical and Ethnomedicinal Uses of Family Violaceae



Deepak Chandra, Gunjan Kohli, Kundan Prasad, G. Bisht, Vinay Deep Punetha, K.S. Khetwal, Manoj Kumar Devrani and H.K. Pandey
 
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ABSTRACT

The genus Viola (Violaceae) consists of approximately 500 species widely distributed throughout the world. Phytochemically, different groups of compounds have been isolated from various species of this genus like cyclotide alkaloids, flavonoids, caffeic acid derivatives, salicylic acid and triterpenoids. Traditional knowledge when tested pharmacologically and phytochemically could provide new effective therapeutic agents. The family Violaceae having an important medicinal herb, mentioned in traditional medicine for a variety of therapeutic applications including purification of blood and the treatment of bruises and ulcers in the Chinese system of medicine it is recommended for use against cancer disorders. The genus mostly used in the traditional medicinal system for cough, cold, flu, fever, malaria and is also given as anticancerous drug. The article reviews is an attempt to compile and documented information on different aspect of Viola species pharmacological properties and highlight the need for research and their potential development.

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  How to cite this article:

Deepak Chandra, Gunjan Kohli, Kundan Prasad, G. Bisht, Vinay Deep Punetha, K.S. Khetwal, Manoj Kumar Devrani and H.K. Pandey, 2015. Phytochemical and Ethnomedicinal Uses of Family Violaceae. Current Research in Chemistry, 7: 44-52.

DOI: 10.3923/crc.2015.44.52

URL: https://scialert.net/abstract/?doi=crc.2015.44.52
 
Received: September 11, 2015; Accepted: November 11, 2015; Published: November 17, 2015



INTRODUCTION

The family Violaceae (alternatively known as Alsodeiacae or Leoniaceae or Retrosepalaceae) comprise of twenty genera and about 800 species (Mabberley, 1987). The plants of this family are perennial herbs or shrubs with simple leaves (alternator opposite) which are palmate or deep dissected shaped, the flowers are bisexual, zygomorphic or actinomorphic, calyx-5, corolla of 5 petals, anterior petal large and spurred. Androecium of 5 stamens. Gynoecium a compound pistil of 3 united carpels, ovules superior and fruit capsule. The family is of little economic importance (Perveen and Qaiser, 2009). It is found naturally in various countries of the world like India, Nepal, Sri Lanka, China, Malaysia, Pakistan and Australia. There is list of some of the Viola species and their worldwide distribution in the Table 1.

In India it is found in various states like Uttarakhand, Utter Pradesh, Himanchal Pradesh, Jammu, Kashmir and Meghalaya etc. Viola species and their distribution in India as in the Table 2.

In India, Viola canescens is found in Pangi Valley of Chamba District in the cold desert of Himalaya also known as Trans Himalayan region (Rana et al., 2010). The presence of V. canescens was also reported in Garhwal region of Himalaya located in Uttarakhand, India at an altitude of 1600-2000 m. It is also present in Uttarakhand in the areas of Nanda Devi National Park and Nainital catchment area (Agnihotri et al., 2012; Shah et al., 2014; Dua et al., 2011). Viola odorata sweet violet is indigenous to India and found in Kashmir (Kangra), Himachal Pradesh (Chamba) and Kumaon hills (Salve et al., 2014).

Table 1: List of some of the Viola species and their worldwide distribution
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Table 2: List of Viola species and their distribution in India
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The main aim of this article is to highlight the latest review of scientifically proved ethnomedicinal uses and secondary metabolites of different species of the Viola.

ETHNOMEDICINAL USES

A large number of ethnobotanical uses of different species of the Viola genus have been documented in literature. After the though literature survey we tabulated the plants name and their uses in Table 3.

Essential oils can be extracted from plant materials by several methods, steam distillation, expression and so on. Among all methods, for example, steam distillation method has been widely used, especially for commercial scale production (Cassel and Vargas, 2006; Di leo Lira et al., 2009). Essential oils have been widely used as food flavors (Burt, 2004).

In the essential oil obtained from fresh aerial parts of V. tricolor has reported 35 compounds representing 97.76% of the total oil as follows: 8 sesquiterpenes, 17 aliphatics, 6 shikimic acid derivatives and 4 monoterpenes. Sesquiterpenes were the major component (59.27%), followed by aliphatics (29.81%), shikimic acid derivatives (8.05%) and monoterpenes (0.30%). The main volatile components found were bisabolone oxide (43.25%), trans-β-farnesene (4.01%) and bisabolol oxide A and B (7.78 and 2.28%) (Anca et al., 2009).

In the essential oil obtained from dried aerial parts of V. tricolor has reported 24 compounds representing 60.53% of the total oil as follows: 14 aliphatics, 4 shikimic acid derivatives, 2 sesquiterpenes and 4 monoterpenes. The main volatile components found were hexahydrofarnesyl acetone (4.06%), methyl salicylate (1.22%) and β-ionone (1.00%). Aliphatic were the major components (42.21%), followed by shikimic acid derivatives (11.20%), sesquiterpenes (4.79%) and monoterpenes (2.32%) (Anca et al., 2009).

The GC-MS analysis of essential oils of the leaves of Viola odorata has reported with 26 volatile components representing 72.13% of the total essential oil obtained from dried aerial parts of V. arvensis as follows: 18 aliphatics, 5 shikimic acid derivatives, 2 monoterpenes and 1 sesquiterpene. Aliphatics were the major components (59.94%), followed by shikimic acid derivatives (8.35%), monoterpenes (2.15%) and sesquiterpenes (1.69%).

Table 3: Ethnobotanical uses of different species of the Viola
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The main volatile components found were 2-pentyl-furan (5.48%), β-ionone (2.09%) and hexahydrofarnesyl acetone (1.69%) (Anca et al., 2009).

The essential oil of Viola odorata flowers contained high percentages of the group of monoterpenes and sesquiterpene. The dominant components were 1-phenyl butanone (22.43%), linalool (7.33%), benzyl alcohol (5.65%), α-cadinol (4.91%), globulol (4.32%) and viridiflorol (3.51%). pulegone (3.33%), epi-α-cadinol (3.05%), terpinen-4-ol (2.31%), germacrene A (1.99%) and paramethyl anisole (1.09%) were also found to be minor components of the V. odorata L. flower oil (Hammami et al., 2011).

The analysis of essential oil composition of the leaves of Viola odorata L. revealed the presence of 25 identified compounds, representing 92.77% of the oil with butyl-2-ethylhexylphthalate (30.10%) and 5,6,7,7a-tetrahydro-4,4,7a-trimethyl-2(4H)-benzofuranone (12.03%) being the two main components (Akhbari et al., 2012).

The flowers of Viola odorata contain a colouring matter and traces of a volatile oil, three acids and an emetic principle called violin, probably identical with emetine, viola quercitrin, closely related but not identical with quercitrin or rutin and sugar. Essential oil from flowers used in perfumery. Pigment extract from flowers used for litmus testing strips. Makes excellent ground cover (Salve et al., 2014). The sweet scent of this flower has proved popular throughout the generations and has consequently been used in the production of many cosmetic fragrances and perfumes companies.

Preliminary phytochemical profile: The methanolic extract of the leaves of Viola odorata was found to contain 15 total phenolic (35.4 mg g–1) and total flavonoid (22.8 mg g–1) contents (Ebrahimzadeh et al., 2010). Various phytochemical constitutes (alkaloids, steroids, tannins, flavonoids and saponins) has been reported in aerial parts of Viola odorata n-hexane, butanolic, methanolic and aqueous extracts (Vishal et al., 2009). The Methanolic extract of the whole plant of Viola betonicifolia has been reported as rich source of alkaloids, flavonoids, tannins, proteins, phenolic compounds, saponins, sterols and triterpenoids (Muhammad and Saeed, 2011). The dichloromethane, ethyl acetate and methanolic extract of Viola tricolor whole plant has been reported as rich source of terpenoids, phenolic compounds, flavonoids and saponins (Witkowska-Banaszczak et al., 2005). The methanolic extract of Viola tricolor has been investigated for their flavonoid contents through LC-MS, HPLC and NMR and five minor flavonoids were identified (Vukics et al., 2008a). Various species of Viola has been tested for their cyclotides contents and all were proved a rich source of cyclotides. The leaves of Viola canescens reported to have alkaloids, phenolic compounds, tannins, saponins, phytosterols and flavonoids as phytochemical constitutes (Barkatullah et al., 2012).

Phytochemical studies: The roots of Viola serpens contains glucoside (methyl salicylate) (Fig. 1), alkaloid (violin) and a glycoside (viola quercitrin) (Fig. 2) (Anonymous, 1978).

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Fig. 1: Methyl salicylate

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Fig. 2: Quercitrin

The Whole plant of Viola serpens containing glycoside methyl salicylate, viola quercitrin, alkaloid voiline gum, mucilage, sugar and saponin (Prajapati et al., 2006). The Viola cornuta (violet) flowers contain volatile oil, rutin, syanyn, bright pigment, methyl salicylate glycosides and anthocyanins. Viola odorata contains alkaloids, glycosides, saponins, methyl salicylate, mucilage and vitamin C (Stuart, 1989). About 30 cyclotides are identified from the aerial parts and roots of Viola odorata, 13 of which are novel sequences (Ireland et al., 2006). The aqueous preparations of Viola odorata flowering tops have anthocyanins (Karioti et al., 2011).

Two isoflavonoids, tectorigenin-7-O-β-D-glucoside and luteolin-7-O-β-D-glucurono pyranoside were isolated from ethyl acetate fraction of Viola patrinii fermentation extracts. (Bachheti et al., 2014). Sources of violae herba include Viola patrinii, V. hederacea, V. arvensis and V. odorata. Previous phytochemical studies of Viola species have reported the isolation of cyclotides and several flavonoid glycosides (Kim et al., 2010; Svangard et al., 2003; Carnat et al., 1998).

The viola is rich in secondary metabolites including, flavonoids, alkaloid (violin, viola quercitin), essential oils including (ionones, α-ionone, β-ionone, β-dihydroionone, hydroquinone dimethyl ether and linolenic), extensively used in diuretic, anti-inflammatory, purogative properties, abdominal pain, skin disorders and upper respiratory complications (cough, sore throat and harash) (Svangard et al., 2004; Walter et al., 2011). Abbasi et al. (2009) had discovered Viola serpens containing glycoside methyl salicylate, quercitrin, alkaloid, voiline gum, mucilage, sugar and saponin. Many research studies have been carried out to figure out the exact number of chemicals in V. canescens. Qualitative testing of ethanolic and methanolic extract of this plant revealed the presence of various compounds. The phytochemicals found in V. canescens include methyl salicylate, alkaloid violin, glycoside violaw12 quercitrin, saponins and glucosides (Rana et al., 2010). An alkaloid was discovered by Dumas and Boullay (1828) in the roots known as violin which are similar to emetine (Fig. 3) but possessing different properties from emetine. It exists in the plant in combined form with malic acid. Some scientists believe that it is remarkably active and may be poisonous. The chemical constituents of viola serpens are alkaloids, saponins, tannins, amino acids, terpenoids, reducing sugars, glycosides and flavonoids (Kumar et al., 2011). It also contains volatile oils such as rutin, cyamin and saponin etc. (Kumar and Digvijay, 2014).

Viola odorata yields saponins, salicylates, alkaloids, flavonoids, saponins, tannins, phenolics and coumarins. Phenolic glycosides, gaultherin, violutoside, saponins, flavonoids and aodoratine (Salve et al., 2014). The literature survey of the genus Viola proved that a large number of pharmacologically active compounds have been isolated from different species.

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Fig. 3: Emetine

Table 4: Secondary metabolites of different species of the Viola
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The genus Viola is a rich source of different classes of natural products like cyclotide alkaloids (Chen et al., 2005), flavonoids (Vukics et al., 2008a, b), caffeic acid, derivatives, salicylic acid (Toiu et al., 2008) and triterpenoids (Tabba et al., 1989) etc., the list of secondary metabolites is presented in Table 4.

CONCLUSION
From the above discussion, it is clear that the family Violaceae is an important plant family with respect to its ethnomedicinal importance. It is widely used in traditional health care system. So this importance builds a pressure on the plant regarding its use. So there is a need to conserve this plant family which is under threat according to the listing of IUCN (International Union for Conservation of Nature). So practical steps are needed for its conservation which include ex situ and in situ conservation. Much more work should be done on studies phytochemistry and essential oils. The structures and composition of different chemical components present in it should be determined for recognizing its further activities. This type of information is required for drug production from this plant for treating various diseases.

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