Research Article
Routine Usage of Medicinal Plants in Northern Jordan
Department of Biosciences, Faculty of Science, Al al-Bayt University, Mafraq, Jordan
LiveDNA: 962.26868
Folk medicine has been a significant source of alternative medicine worldwide for centuries, especially in countries with great variation in geography and climate due to the wide diversity of plant species available1. Use of herbal medicines also tends to be more common in rural and underdeveloped areas that lack access to modern medicine. In Jordan, about 2000 plant species are estimated to play a very important part in everyday life as traditional medicines 2. Studies conducted in Wadi Mujib, Ajloun and Tafila regions of Jordan have begun to classify the importance of various medicinal plants using information consensus factor (ICF) and usage value (UV) as indicators3-5. ICF value links citations of several plant species groups based on ailment treatment, however UV represents recorded use per species. Previous studies showed the highest UV in Mujib for digestive disorders3. Crocus hyemalis (saffron) showed the highest UV in Mujib3, while Matricaria aurea (Loefl.) and Allium cepa L. had the highest UV in Tafila5. Besides, kidney and digestive problems had the highest ICF in Ajloun and Tafila, respectively4, 5.
Irbid and Zarqa have the second and third largest metropolitan populations in Jordan, with 1,819,600 and 1,403,000 inhabitants in 2016, respectively6. Irbid is located in northern Jordan, 70 km north of Amman, about 20 km away of the Syrian border and surrounded by Um Qais, Al koura, Mafraq and Al Ramtha. It is divided into 23 city districts, has an overall area of 1500 km2 and its climate is hot in summer and cold, wet and snowy in winter, with a recorded rainfall range of 234-400 mm in 2015/20166. Zarqa is also located in northern Jordan, 24 km northeast of the capital, Amman. It is divided into 5 districts and has an overall area of about 4761 km2. Zarqa has a moderate climate, with an annual recorded temperature average of 17.4°C and annual rainfall ranging from 102-109 mm in 2015/20166.
In 2014, Oran reported that medicinal plants in Jordan are in danger of disappearing due to human activities, such as construction of buildings and trails, urbanization, random livestock grazing and continuous excessive use5,7,8. Uncontrolled use of Jordanian herbs as a source of food, fuel and traditional medicine creates a challenge for herbalists because it is very difficult to keep records of the enormous variation of plant species for coming generations5. Many herbs grown in Jordan are grown in other areas and countries; however, research evaluating local knowledge regarding their medicinal use and commercial potential is limited9-11. Therefore, the present study examined the medicinal applications of some of the most commonly used herbs found in northern Jordan, specifically Zarqa and Irbid, to determine their UV and perceived significance for the treatment of various ailments. Importantly, this study helps preserve local ethnopharmacological knowledge and provides foundational information on the medicinal-chemical potential of these plants, which may be useful for new drug development.
Participants and questionnaires: The present study was conducted from March to June 2017 in northern Jordan. A survey questionnaire was administered to people residing in the cities of Zarqa and Irbid through face-to-face interviews. The questionnaire included both closed and open questions, covering demographic characteristics of participants and names of some local medicinal plants, their utilized parts, method of use and usage frequency. Surveys were conducted by 7 students enrolled in a biological sciences course who received prior instruction on their proper administration. Each student was asked to approach 15 participants. Data collection was systematized to reflect reality and truthfulness. Prior to participation, respondents were informed of how their answers would be used as part of the study and that any identifying information would remain private.
UV index: The utilization of 13 medicinal herbs grown in northern Jordan was assessed according to a UV index, which numerically evaluates the relative importance of each plant species as a home remedy based on respondent plant usage answers. The UV was calculated with the following formula:
where, U represents the number of uses per species and N is the number of respondents.
Data regarding the utilization of 13 medicinal plants [Aloysia citriodora, Cinnamomum verum, Elettaria cardamomum, Hibiscus sabdariffa, Matricaria aurea (Loefl.), Mentha piperita (L.) Huds, Paronychia argentea Lam., Pimpinella anisum, Rosmarinus officinalis, Salvia officinalis, Syzygium aromaticum, Thymus vulgaris and Zingiber officinale] grown in Irbid and Zarqa was assessed according to a UV index.
A total of 108 participants were included in the present study, consisting of 38 males and 70 females. The medicinal plants used were either cultivated by the respondents, harvested from the wild and /or purchased from an herbalist (E. cardamomum, Syzygium aromaticum, C. verum and Z. officinale).
Table 1: | Comparison of respondent sex, education level and medicinal plant usage |
About 76% of all respondents were interested in using medicinal plants on a daily basis; of them, the majority were female (88.57% versus 52.63% of males, Table 1). About 65% of highly educated females showed a tendency to use traditional herbs compared to 50% of highly educated males.
Common medicinal uses for all 13 herbs surveyed are summarized in Table 2. Respondents used various herbs to prepare drinks frequently throughout the entire year. The leaves of the plants were used most often, along with flowers, flower buds, fruits and roots. Herbal treatments for several ailments were most often prepared as infusions or decoctions. Overall, plant species in the Lamiaceae family were most commonly used in Zarqa and Irbid. In particular, Salvia officinalis had the highest usage (UV = 0.88) followed by Mentha piperita (L.) Huds (UV = 0.8), Pimpinella anisum (UV = 0.76), E. cardamomum (UV = 0.68), Matricaria aurea (Loefl.) [UV = 0.63], Z. officinale (UV = 0.56), T. vulgaris (UV = 0.49) and H. sabdariffa (UV = 0.44). Usage of Syzygium aromaticum, R. officinalis, A. citriodora and Paronychia argentea Lam. was less common (UV = 0.29, 0.17, 0.1 and 0.07, respectively; Table 2). Medicinal plants reportedly used to treat various categories of ailments are summarized in Table 3.
People living in Zarqa and Irbid, Jordan, can be categorized into two distinct communities based on their residential location (rural versus urban) and both communities are aware of and use medicinal plants according to their shared traditional and cultural heritage. In the present study, a survey of 108 residents of Zarqa and Irbid was employed to obtain information on current usage of medicinal plants in northern Jordan in order to determine their perceived value for treating various ailments. Females reported greater reliance on herbal remedies than males, a higher level of education obviously tempered usage for both sexes. Nonetheless, usage of medicinal herbs for treatment of various ailments was still relatively prominent among the sampled respondents, reportedly due to their availability, pleasant tastes and smells, low cost and continued widespread belief that herbal remedies are safer than modern medications. Medicinal plants were grouped into different categories based on their home remedies usage, to treat ailments of the systems: Circulatory, digestive, respiratory, reproductive, nervous and urinary systems, besides to diabetes, skin, dental and liver problems.
Digestive system problems: The present results revealed that 7 of the 13 herbs examined are still used in northern Jordan to treat gastrointestinal problems, including colic, diarrhea, stomach ulcers, infections and constipation. Of them, Salvia officinalis, Mentha piperita (L.) Huds, Pimpinella anisum, E. cardamomum and Matricaria aurea (Loefl.) were the most frequently used for digestive disorders according to UVs (range, 0.63-0.88), whereas Paronychia argentea Lam. and R. officinalis were less common (UV = 0.07 and 0.17, respectively). Salvia officinalis (sage) has been used for centuries in traditional medicines of Asia, Latin America and Europe as well as by the German Commission as a treatment for diarrhea, hyperglycemia, dyspepsia, ulcers and paralysis12 and has also been reported to reduce throat pain in patients with pharyngitis13. Studies of Mentha piperita (L.) Huds (peppermint) oil suggest its efficacy in the treatment of functional dyspepsia and irritable bowel syndrome by facilitating the relaxation of gastrointestinal muscle via an antagonistic effect on calcium channels14-16 and its in vivo application has been shown to induce a significant spasmolytic effect on the gastrointestinal tract17. Furthermore, menthol, a main chemical component of peppermint oil, was also shown to cause relaxation of the gastrointestinal tract during endoscopy by affecting calcium channels18-20.
Use of Pimpinella anisum (anise) seeds reportedly has several beneficial effects, from teeth polishing to carminative and antidiarrheal21,22. In addition to its laxative effects23, Pimpinella anisum has also been shown to act as an antiulcerative agent against chemically-induced gastric ulcer24.
Table 2: | Plants used for treatment of various human health problems in Zarqa and Irbid, Jordan |
Table 3: | Medicinal plants used to treat various ailments in Zarqa and Irbid, Jordan |
Similar to anise, E. cardamomum (cardamom) seeds were chewed by ancient Egyptians to wash teeth and stimulate digestion, as well as for their antiemetic and antidyspeptic properties25,26. Mixing cardamom seeds with ginger, cloves and caraway has also been used for to alleviate digestive problems27. In Jordan, cardamom seeds are used in traditional Jordanian Arabic coffee, a welcoming daily hot drink that is consumed multiple times a day (morning and evening) throughout the whole year, typically before and after meals. They are also used as a seasoning for the famous Jordanian traditional lunch known as Mancef. Matricaria aurea (Loefl.) [golden chamomile] extract has been shown to effectively treat induced acute colitis in rats, suggesting its use for treatment of ulcerative colitis in humans28. Moreover, its usage as a daily food additive was reported to protect against ulcers28. Lastly, use of R. officinalis (rosemary) to treat gastrointestinal disturbances due to its ulcerogenic, carminative and antidyspeptic properties has also reported29-31.
Respiratory system problems: The results of the present study demonstrated that 6 herbs are currently being used in northern Jordan to treat respiratory ailments, such as bronchitis, cough and asthma. Mentha piperita (L.) Huds was most frequently used for respiratory issues (UV = 0.80) followed by E. cardamomum (UV = 0.68), Matricaria aurea (Loefl.) [UV = 0.63], Z. officinale (UV = 0.56), T. vulgaris (UV = 0.49) and Syzygium aromaticum (UV = 0.29). Although Mentha piperita (L.) Huds, Matricaria aurea (Loefl.) and Syzygium aromaticum are widely used in Jordanian folk medicine for many purposes, published research evaluating their impact, if any, on the respiratory system remains unavailable. On the other hand, cardamom has been shown to have beneficial effects on cold and cough32, while other have indicated the use of thyme for treatment of respiratory diseases, with a remarkable effect on bronchial asthma33,34. In traditional Chinese medicine, Z. officinale (ginger) is used as a treatment for respiratory conditions, bronchitis and rheumatism and has been shown to significantly reduce dry cough, flu symptoms and asthma35.
Nervous system problems: The current results indicated a total of 6 plant species were cited as being used for treatment of nervous system issues, including depression, mood changes, memory problems, anxiety, insomnia, stress, sleep problems, epilepsy and headaches. In particular, Mentha piperita (L.) Huds was most frequently used (UV = 0.80) followed by Pimpinella anisum, E. cardamomum and T. vulgaris (UV range, 0.49-0.76), whereas R. officinalis and A. citriodora were less common (UV = 0.17 and 0.10, respectively). While peppermint is still used by many in Zarqa and Irbid to treat headaches, studies of its effects on headaches are still absent from the literature. In contrast, anise has been shown to elicit a sedative effect similar to aspirin and morphine36 and ingestion of anise via capsule can significantly reduce pain intensity in dysmenorrhea cases compared to an mefenamic acid capsule37. Moreover, subcutaneous injection of anise essential oil reportedly has an anti-anxiety effect in mice38. Use of thyme is recommended for both physical and mental fatigue, exhibiting significantly positive effects on anxiety, insomnia, depression and mood changes39. Rosemary has been shown to have beneficial effects on memory via acetylcholinesterase inhibition in brain40,41 and its calmative and antidepressant effects may be a consequence of its antioxidant capabilities and impact on gamma-aminobutyric acid receptors41. Interestingly, A. citriodora palau (lemon verbena) has been reported to play a role in treating Alzheimer’s disease in addition to insomnia and anxiety42-44, causing positive changes in mood and cognitive activity43 possibly by affecting acetylcholine receptor activity in the central nervous system45.
Dental problems: Herein, 4 species of medicinal plants were used by respondents for dental problems, such as toothaches, dental emergencies and bad breath. Of them, E. cardamomum was used the most (UV = 0.68) followed by Z. officinale (UV = 0.56), T. vulgaris (UV = 0.49) and Syzygium aromaticum (UV = 0.29). Cardamom is known to have been used by Egyptians as a tooth cleaner25 and ginger and Syzygium aromaticum (clove) are indicated as toothache remedies, especially due to their antibiotic, antimicrobial and anti-inflammatory effects35,46. The analgesic effects of clove have been attributed to its influence on Na+/Cl channels and receptors in the ganglion cells46. However, there are currently no studies available on the use of thyme for dental care or problems.
Genitourinary system problems: The present results revealed that 3 of the 13 plant species assessed are still being used in northern Jordan to treat genitourinary problems. Though all are used to treat urinary infections and kidney stones, T. vulgaris is used the most (UV = 0.49), with R. officinalis (UV = 0.17) and Paronychia argentea Lam. (UV = 0.07) use being much less common. Thyme’s role in relieving renal infections has been reviewed previously47 and although rosemary and Paronychia argentea Lam. (silver nail root) are used in Zarqa and Irbid as home remedies, there are currently no documented studies available on their treatment of genitourinary system issues48.
Diabetes: A total of 3 plant species were cited in the current study as being used to treat diabetes and related symptoms, such as hyperglycemia. Of them, Salvia officinalis (UV = 0.88) and C. verum (UV = 0.67) were used most frequently followed by H. sabdariffa (UV = 0.44). Use of clove has been shown to significantly reduce blood glucose, total cholesterol, triglycerides and low-density lipoprotein levels in type 2 diabetic patients but have no significant effect on fasting blood glucose levels in type 2 diabetic patients or healthy female volunteers49-51. Cinnamon has been shown to reduce insulin resistance52,53 and lower fasting blood sugar levels from 10% to 29%54-56 by slowing the enzymatic digestion of carbohydrates in the digestive tract57. Furthermore, a compound derived from cinnamon (hydroxychalcone) was found to mimic the role of insulin in glucose uptake58. The antidiabetic properties of H. sabdariffa (roselle) were also recently reported59.
Circulatory system problems: In the present study, only 2 herbs, Z. officinale (UV = 0.56) and H. sabdariffa (UV = 0.44), were cited for the treatment of circulatory system issues, including blood pressure, circulation and heart problems. In traditional Chinese medicine, ginger is used to improve the flow of blood and other bodily fluids, stimulate heart muscle and reduces blood pressure35,60,61. Ginger contains many confirmed hypotensive and vasodilating compounds able to reduce blood pressure62, some of which induce vasodilation when nitric oxide is released while calcium is blocked62. Ginger has also been reported to have antithrombotic activity63,64, inhibit cholesterol increases by reducing its absorption in the blood and liver and prevent oxidation of low-density lipoproteins, which is necessary for cholesterol accumulation in arterial lumina26. Moreover, two studies have recently identified a role for roselle in blood pressure control65,66. Interestingly, daily administration of roselle was reported to effectively lower mild to moderate hypertension66.
Skin problems: Herein, only 2 herb species, Matricaria aurea (Loefl.) [UV = 0.63] and T. vulgaris (UV = 0.49), were noted as being used for skins issues, including acne and insect stings/bites. Although, golden chamomile has been shown to have antimicrobial and anti-inflammatory activity67, there are currently no reports on its use for treating skin problems. Thyme, on the other hand, has been shown to possess antiviral, antifungal and antibacterial activity34,47 and its effect on skin issues, such as oily skin, sciatica, acne, dermatitis and bug bites/stings and other integumentary ailments, has been reviewed previously38.
Liver problems: A total of 2 plant species, T. vulgaris (UV = 0.49) and H. sabdariffa (UV = 0.44), were cited herein as being used for general liver problems. Oral administration of aqueous sage and thyme extracts have been shown to increase resistance to oxidative stress68 and thyme extracts were suggested to prevent the occurrence of liver diseases68. Roselle was previously reported to have a positive impact on liver disease via elimination of free radicals and conserving hepatic enzyme activity69,70. In addition, roselle extracts have been found to prevent fat deposition in the liver and abdomen71.
Menstrual cramps: Pimpinella anisum (UV = 0.76) was the only herb used by respondents in the present study to treat menstrual cramps. The role of anise for treatment of menstrual cramping was reviewed previously22. Furthermore, daily consumption of anise by capsule for 1 month has been shown to attenuate the occurrence of hot flashes in postmenopausal women72 and is highly effective for relieving pain, hence its recommended use for dysmenorrhea37.
By examining the medicinal applications and UV of some commonly used herbs found in northern Jordan, the present study is helping to document local ethnopharmacological knowledge that may provide important information related to the medicinal-chemical potential of these plants, which can be used for drug development. Further studies are needed to document other medicinal plants used in traditional Jordanian folk remedies and examine their regional usage and value.