During the last century, the relationship between wild edible plants (WEP) – as part of traditional food habits – and health gained the interest of the scientific community(Reference Grivetti and Ogle1). Nowadays, the health status of populations is witnessing increasing incidences of chronic diseases, partly influenced by current dietary changes such as increases in fat, sugar and total energy(Reference Popkin2). In contrast, traditional food habits have been characterized by dietary diversity and have been associated with low health risks(Reference James, Duthie and Wahle3, Reference Trichopoulou and Vasilopoulou4). WEP have been identified as main components of these diets and as important contributors to their health-protective properties(Reference Simopoulos5).
Wild plants are defined as ‘those that grow spontaneously in self-maintaining populations in natural or semi-natural ecosystems and can exist independently of direct human action’(6). Undomesticated greens have always been a main part of traditional diets, and were famous for their health and medicinal qualities among local communities and indigenous people long before their nutritious, protective and therapeutic effects were proved by science(Reference Etkin7). Many wild species, neglected in urban diets, are collected from the surrounding environment and consumed as part of local diets, especially in times of shortage(Reference Cooper, Spillane, Anishetty and Griffee8, Reference Johns and Sthapit9). Various wild greens contain high nutritional values with relatively low energy. Compared with commonly eaten vegetables, they provide the diet with greater amounts of minerals(Reference Trichopoulou, Vasilopoulou and Hollman10, Reference Turan, Kordali, Zengin, Dursun and Sezen11). Additionally, several of these often-called ‘famine foods’ have proved to be important sources of high-quality protein and essential amino acids when compared with the WHO protein standard, as well as being rich in n-3 and n-6 essential fatty acids(Reference Freiberger, Vanderjagt, Pastuszyn, Glew, Mounkaila, Millson and Glew12). Their antioxidant property, mainly from phytochemicals, was found to be two to three times higher than that of common vegetables(Reference Trichopoulou, Vasilopoulou and Hollman10). For these reasons, undomesticated greens are recognized as possessing a significant potential for widespread use and development, promoting global food security and nutrition(Reference Cooper, Spillane, Anishetty and Griffee8).
Unfortunately, it has been documented that only 0·2 % of edible plant species are cultivated and consumed, while only 0·0001 % contribute the most to the world population’s energy needs(Reference Cooper, Spillane, Anishetty and Griffee8). Therefore, there is a need to reveal potential nutritious and therapeutic properties of neglected wild plants that could contribute to the health and wellness of rural communities.
Traditional knowledge and experience are a golden source for the exploration and collection of wild plants. Indigenous people are ‘people who…developed ways of living, practices and belief systems which demonstrate their intimate relationship with the mountain environment and deep knowledge about the plants, wildlife, vegetation and ecosystems that surround them’(Reference Xu and Mikesell13). This set of beliefs forms the basis for participatory approaches, with the aim of reaching economic and sustainable development in local communities(Reference Warren14). Ethnobotany, the systematic study of traditional communities’ botanical knowledge, permits the disclosure of various characteristics and benefits of WEP that were revealed through the ancient interaction between man and nature(Reference Salmon15).
In the Mediterranean basin, there seems to be a wealth in ethnobotanical studies, mostly coming from southern Europe and some Middle Eastern countries(Reference Abu-Rmaileh and Afifi16–Reference Pieroni, Nebel, Quave, Munz and Heinrich22). However, no recent studies have been conducted on traditional knowledge regarding the uses and health and medicinal properties of WEP in Lebanon.
Therefore, the leading objective of the present study was to record the traditional knowledge of local north-eastern Lebanese inhabitants concerning the use, consumption and perceived health and medicinal properties of the following six species of native WEP: Cichorium intybus (chicory), Foeniculum vulgare (fennel), Malva sylvestris (high mallow), Gundelia tournefortii (gundelia, locally ‘Akkoub’), Eryngium creticum (eryngo) and Thymus syriacus (wild thyme). These plants were chosen based on their perceived importance by the population in the surveyed communities through focus group discussions. Highlighting the role of these plants as a key resource for the health and nutritional livelihood of rural communities enforces national efforts to conserve them and promote their sustainable use through community-based programmes.
The current project is a qualitative research, part of a larger nutrition study conducted at the American University of Beirut in Lebanon.
Methodology
The study was conducted during the months of June and July 2004. Towns from the north-east of Lebanon were targeted. The research area included a total of eighteen towns/villages. The villages fall in the Bekaa Valley – the main agricultural land of Lebanon – in between the two Lebanese mountain chains.
The participants were selected through ‘purposeful’ or ‘criterion-based’ sampling(Reference Maxwell23). This method consists of choosing participants according to predefined criteria set by the researcher to get the most information to answer the research question. In our study, ‘purposeful sampling’ was most useful in gathering a considerable amount of specific, detailed information. One or several contact persons helped us locate our informants in each village. Four criteria determined the choice of participants for inclusion. First, the participants had to be native and resident of the north-east region. Second, they had to be reputable – in their community – for their knowledge regarding plants and their properties. The third criterion was their self-identification as individuals who are familiar with wild plants and their uses, from personal experience, personal interest and readings, or from inheritance of the knowledge from their parents or other older members of their larger family. Personal assessment of the informant’s knowledge was the last criterion for selection. This was decided during the first encounter with the candidate, after initiating a general conversation and posing several probing questions regarding their familiarity and use of WEP for both nutritive and medicinal purposes. Thus, informant’s age, gender, educational level, profession and socio-economic status were not considered as criteria for either inclusion or exclusion in the study. Ethical approval from McGill University’s Faculty of Agricultural and Environmental Sciences in Canada was obtained before initiating the interviews.
A structured, semi-qualitative questionnaire was used to collect data(Reference Martin24). The questionnaire was divided into six identical parts, each for one plant. Each part was subdivided into two sections: the first covered the edible uses and consumption forms of the plant, while the second investigated the plant’s properties and uses for health and medicinal purposes. The questionnaires were translated into Arabic and each interview took around 90 to 120 min. All interviews were conducted by the same researcher.
The information collected in the field was both quantitative and qualitative. The quantitative data consisted of the consumption patterns of the plants. The percentage of participants’ responses as per the edible uses, preparation, consumption and taste preference, as well as the perceived significance and health and medicinal uses of the plant, is used to report this information. The qualitative data were obtained in the section covering the health and medicinal properties of the plants. First, responses from the question ‘What are the health and medicinal properties of the plant?’ were quantified using the categorization method(Reference Maxwell23). Categories of health/medicinal properties were devised as mentioned by the informants, and properties and patterns of health and medicinal use started emerging as participants repeatedly referred to the same use/uses of the plants. Second, results are reported as per ‘the informant consensus method’(Reference Phillips25). This method reflects the value of each plant as per property or use by the degree of agreement between distinct, independent participants on the same property or use. In the present study, a minimum of three separate accounts of the same use or property of the plant was required in order to report it as a significant pattern in the results, similar to what has been used in other ethnobotanical studies(Reference Azaizeh, Fulder, Khalil and Said18, Reference Yaniv, Dafni, Friedman and Palevitch26).
Results and discussion
Thirty participants were interviewed. The majority were males. Participants averaged 62 years of age. They were all Lebanese, native to the north-east region.
Consumption patterns and uses for edible purposes
As shown in Table 1, most informants knew and personally consumed all six plant species. Reports on population consumption patterns illustrate an increasing trend in the consumption of chicory, high mallow, wild thyme and gundelia (Akkoub). Fennel and eryngo show no salient trends. Most informants are not aware of the degree to which fennel is consumed in the population. The main explanations provided by participants in this regard are that few people know it and it is used for treatment only. As for eryngo, answers are scattered between increase, decrease or unawareness of consumption trends. The reason for these differences is that consumption trends depend on people’s familiarity with the plant.
Frequency data for familiarity and consumption of the six species of wild edible plants in north-east Lebanon
*’Don’t know’ includes imprecise answers and/or responses outside the question.
†These categories are specified by the informants for the ‘specific flavour’ choice of answer provided in the question.
All plants are consumed mainly during the spring season, starting in late winter (i.e. February). Chicory, eryngo and Akkoub are not consumed during summer and autumn, while fennel, high mallow and wild thyme are consumed, although to a lesser extent, all year round.
Informants eat mainly the leaves and stalks of chicory, eryngo, high mallow and wild thyme. There is less consumption of fennel stalks and more consumption of its seeds as compared with the other plants. As for Akkoub, the main edible part is the stalk. Many answers fall under the category ‘all of it’. We have reason to believe that this category refers to the leaves and the stalks since various informants specified it as such.
Chicory, eryngo, high mallow and Akkoub are consumed mainly when freshly gathered. Chicory is eaten both raw and cooked, eryngo is prepared mainly raw as a salad, and high mallow and Akkoub are usually eaten cooked. Fennel and wild thyme are consumed both fresh and preserved. When freshly collected, fennel is consumed both raw and cooked. Its seeds are preserved by shade drying and are consumed cooked, either by boiling them and drinking their infusion or as spices added to food and desserts. When fresh, wild thyme is consumed raw in a salad. When preserved (shade- or sun-dried), it is consumed raw, ground and mixed with sesame seeds, sumac, salt and olive oil or is pickled for flavouring.
Most informants find the plants appetizing. Chicory and eryngo are described as bitter in taste. Bais and Ravishankar reported that the bitter taste of chicory is attributed to a variety of phytochemicals, namely sesquiterpene lactones, the main bitter compounds being the glucoside of fructose and catechuic acid(Reference Bais and Ravishankar27). Fennel is described as sweet and similar to aniseed in taste. Anethole, found in both fennel and aniseed, is the sweet chemical responsible for the plant’s peculiar flavour(Reference Harborne and Baxter28). Akkoub and high mallow’s tastes were difficult to describe; they are mainly identified as sweet. Wild thyme is mainly sharp in taste. Thymol and carvacrol are the two main compounds found in T. syriacus essential oil(Reference Tumen and Baser29).
Regarding the average consumption in season, high mallow and Akkoub are consumed once per week, chicory and fennel are eaten twice weekly, eryngo is consumed about three times weekly, while wild thyme is the most frequently eaten plant, around five times weekly. There is no pattern of consumption of chicory, eryngo, fennel and Akkoub when out of season, while there is more reporting of out-of-season consumption for high mallow and wild thyme. High mallow is being used as needed, for medicinal purposes, by nine out of twenty-seven informants; while wild thyme is reported by eight out of seventeen respondents to be consumed, on average, four or five times weekly (data not shown).
Uses for health and medicinal purposes
As for the perceived significance, health and medicinal uses of the plants (Table 2), most informants value the plants mainly for their edible use and believe that they have health and medicinal properties. Compared with the others, chicory has a noteworthy religious significance as it was mentioned for its health benefits by the prophet Mohammad in Islam according to some participants. Akkoub was referred to mainly as a nutritious food; thus it is not mentioned in the following discussion regarding the preparation, consumption and uses for health and medicinal purposes.
Frequency data for perceived significance, heath and medicinal usesFootnote * of the six species of wild edible plants in north-east Lebanon
* Detailed explanations of answers regarding the preparation of the plants are provided in the text.
† Informants either replied with a ‘No’ or gave no answers because the question was ambiguous to them.
The parts consumed for health and medicinal properties are the same as those used for edible purposes; i.e. the leaves and stalks of all of the plants and the seeds of fennel. As for the preparation and consumption for health and medicinal uses, chicory is mainly consumed cooked or raw, and eryngo is eaten raw, as they are prepared for edible purposes. Fennel is mainly boiled and drunk, the seeds being the most common part used, with ten out of fifteen informants using them boiled/infused and drunk (data not shown). Wild thyme and high mallow are mostly boiled and drunk. More specifically, we noticed a wide variation in the preparation and use of high mallow for health and medicinal purposes. The plant can be cooked and eaten as it is prepared for its edible consumption. For external applications, high mallow is prepared as a raw and/or a cooked poultice. Similarly, it is boiled and its water is used to wash injuries and inflamed tissues (female genitalia, pimples), or even as a gargle for throat inflammations.
When informants were asked if they prepare the plants for prevention purposes against sickness, the response rate was very low. Reasons could be that people either did not relate to the question or did not regard consuming these plants for prevention against ailments, rather they consumed them as popular traditional dishes while benefiting from their health and medicinal properties when needed.
As for mixing the plants with other herbs for better or different health results, the majority of informants do not mix chicory and high mallow with other herbs. Eryngo and wild thyme could be either prepared alone or with other herbs, and fennel is mostly mixed with other herbs. For all of the plants, there is no consistency as to mixing the plant with a specific herb for the treatment of a particular ailment. However, among various herbs mentioned throughout all questionnaires, we found that six were mentioned at least three times by three different informants. The plants are the following: Centaurea spp., Chamaemelum nobile (chamomile), Rosmarinus officinalis (rosemary), Prunus dulcis (almond), Althea spp. and Adenocarpus divaricatus (also known as Adenocarpus complicatus). These plants are worth further investigation for their health and medicinal value among rural communities.
Responses regarding the dosage of the plant for medicinal uses were difficult to categorize since the quantities were not measured; therefore we had to estimate doses used. An amount of one cup of raw chicory or a liberal quantity (until satiety) is consumed. Mostly one raw cup of eryngo and high mallow is used. Fennel and wild thyme are used in tablespoon amounts.
As for the frequency of preparation for treatment, the main salient category for chicory, eryngo, fennel and high mallow is their daily consumption until the symptoms are relieved. A daily consumption not exceeding a certain period of time (usually ranging from few days up to two weeks) is noticed for high mallow and fennel. Wild thyme is mostly consumed as needed.
High mallow and wild thyme are the only two plants mentioned to have side-effects due to over-consumption. Three informants stated a hypotensive effect of thyme. In rat models, Aftab et al. reported a dose-dependent hypotensive and a cardio-relaxant property of thymol, isolated from a herb that was traditionally used for its blood-pressure-reducing effects(Reference Aftab, Rahman and Usmanghani30). As for high mallow, three respondents mentioned diarrhoeal effects and five pointed out that it caused anaemia. The plant’s leaves contain a mucilage responsible for its anti-inflammatory properties(Reference Gonda, Tomoda, Shimizu and Yamada31). Mucilage has been also shown to induce an increased bowel movement in rat models(Reference Begin, Vachon, Jones, Wood and Savoje32). A similar question investigated groups of people who should avoid use of the plant. The purpose of this question, asked at a later stage, was to stimulate the memory of the participant for similar information that might have been forgotten or missed in the previous question. Three informants said that wild thyme should be avoided by people suffering gastrointestinal disturbances. In fact, thymol, which is a major compound of thyme’s essential oil, is known to ‘irritate the gastric mucosa’(Reference Harborne and Baxter28). Four informants mentioned that high mallow should be avoided by anaemic patients. To our knowledge, there are no scientific reports referring to the anaemia-causing effects of high mallow or other Malva species. Further investigation into this aspect would help shed light on the plant’s toxicity level.
The plants are used by all age groups, with high mallow and wild thyme being employed more than the others for infants. They are also used by both men and women, with no differences in administration of the plant depending on gender.
Informants’ knowledge is mainly inherited from their parents and ancestors. Some developed their understanding by personally experimenting with the plants, and knowing about ancient traditional medicine from personal reading about Arabic herbal medicine and the medicine of the Prophet. One informant mentioned getting his knowledge about plants from Bedouins passing through the village.
Table 2 summarizes the perceived health and medicinal properties of the six WEP. This table mainly includes answers to the question: ‘What are the health/medicinal effects of this plant? Please specify’. Another question, ‘Does any specific category of patients require this plant?’, intended to revive the memory of participants as to who might benefit from the therapeutic effects of the plant. The results are discussed below.
Chicory
Previously, traditional reports have described chicory as having antipyretic, anti-colic, hypoglycaemic and hepatic properties(Reference Al-Khalil17, Reference Bais and Ravishankar27, Reference Duke33, 34). In Lebanon, chicory is commonly known as ‘Hindbeh’, and is renowned for its digestive properties as a laxative and its blood properties in terms of treating anaemia. As for its effects on the blood, chicory is mainly reported to ‘treat anaemia’ and to ‘strengthen blood’, which we believe also implies ‘treating anaemia’. In fact, five of the informants who had mentioned that it strengthens the blood specified later on during the interview that it treats anaemia. Looking at its nutritional profile, chicory stands out as a rich source of folate, containing 110 mg of folate per half cup of chopped raw chicory(Reference Pennington35). Therefore, an increased consumption of chicory might explain its reported properties in cases of folate-deficiency related anaemia in the community. As for reports on its digestive properties, chicory is described to be bitter in taste and bitter plants have been used to treat digestive tract disturbances among various traditional communities(Reference Weimann and Heinrich36), relieving gastrointestinal pains(Reference Heinrich37). Several sesquiterpene lactones found in chicory confer the bitter taste to the plant(Reference Bais and Ravishankar27). The laxative effect of chicory can be explained by its high content of dietary fibre, having 3·6 g of dietary fibre per half cup of chopped raw chicory(Reference Pennington35). Moreover, inulin, an indigestible carbohydrate, is found to some extent in the stalk of the plant(Reference Ernst, Chatterton and Harrison38). Inulin, like other dietary fibres, increases bowel movement(Reference Roberfroid39) and is thus responsible for the laxative and digestive-stimulant properties referred to by informants in the current study. Other reports of hepato-protective activity(Reference Rasheeduz and Mujahid40, Reference Ki, Yim and Lee41) and hypoglycaemic effects(Reference Ki, Yim and Lee41–Reference Vasanthamani and Savita43) of chicory are well supported by previous scientific literature. Particularly, Salvatore and colleagues(Reference Salvatore, Pellegrini, Brenna, Del Rio, Frasca, Brighenti and Tumino44) highlighted the total antioxidant capacity of C. intybus, analysed after being traditionally prepared for edible purposes by boiling, suggesting that chicory’s abundant β-carotene and phenolic acids may confer health-protective properties to the plant.
Fennel
In other different traditions, fennel is known for its laxative properties. It is also used as a muscle relaxant as well as to treat urinary disorders(Reference Al-Khalil17, 34, Reference Heywood45). In Lebanon, fennel, known as ‘Shumar’, is used for its therapeutic effects on the gastrointestinal system as a pain reliever as well as for its diuretic properties. Experimental as well as human studies demonstrated that fennel oil had anti-spasmodic and relaxing effects on smooth muscles(Reference Lis-Balchin and Hart46–Reference Alexandrovich, Rakovitskaya, Kolmo, Sidorova and Shushunov48). This activity is due to the similarity found between anethole, the major component in fennel oil, and the neurotransmitter dopamine(Reference Alexandrovich, Rakovitskaya, Kolmo, Sidorova and Shushunov48). In animal studies, fennel was proved to have significant diuretic effects(Reference Beaux, Fleurentin and Mortier49), which explains our informants’ narratives.
High mallow
A review of the literature revealed that high mallow has been traditionally used as a laxative and an anti-inflammatory agent(Reference Al-Khalil17, 34). Known as ‘Khebayzeh’ to our informants, the majority agreed on high mallow’s anti-inflammatory properties. Gonda et al. isolated a polysaccharide from mallow’s leaves showing an anti-complement activity, thus modulating the inflammatory response(Reference Gonda, Tomoda, Shimizu and Yamada31). Moreover, nutrient analysis of a different species of Malva eaten in Turkey highlighted the plant as an important vegetable source of Zn, necessary for a healthy immune system(Reference Turan, Kordali, Zengin, Dursun and Sezen11). As previously recounted, the laxative effects of high mallow could be attributed to its high mucilage content. Another species of Malva, used in traditional medicine as a laxative, contains polysaccharide moieties(Reference Shimizu and Tomoda50) similar to those found in M. sylvestris.
Wild thyme
There are no previous reports regarding the traditional medicinal uses of T. syriacus. However, reports of other species in the same genus, such as Thymus bovie and Thymus capitatus, highlight the traditional therapeutic uses of thyme. For instance, T. bovie was reported to facilitate digestion, while T. capitatus was known for its relief of respiratory distress and urinary infections, its stimulation of gastric function(Reference Al-Khalil17) and its utilization as a cardiac and anti-tussive agent(Reference Abu-Rmaileh and Afifi16).
Commonly known as ‘Zaatar’ in the Lebanese dialect, the main health patterns characterizing T. syriacus were its beneficial effects regarding gastrointestinal disturbances and its anti-poisonous properties. Previous literature has acknowledged the bactericidal properties of Thymus vulgaris (Reference Fleming51), mainly due to its content of two active ingredients – thymol and carvacrol(Reference Saleh and El-Nofey52) – which have demonstrated high bacterial growth inhibition(Reference Knobloch, Weis and Weigand53). These compounds are also two of the main components of T. syriacus essential oil(Reference Tumen and Baser29). This property of thyme might help in treating mild food poisoning and relieving its symptoms. Remarks regarding the disinfectant properties of thyme (eight out of twenty-eight informants), with four out of eight respondents specifying that it kills germs and microbes, further rationalize this salient pattern.
As for thyme’s therapeutic effects regarding the respiratory tract, informants’ accounts correlate with previously reported activities of Thymus species, namely vulgaris and serpyllum, to be effective in clearing respiratory phlegm and relieving coughs(Reference Fleming51).
Eryngo
Previous traditional reports stressed the use of eryngo as an antidote for scorpion poison, as well as for its hypoglycaemic effects(Reference Al-Khalil17, 34). Commonly known in Lebanon as ‘Qors Aanneh’, eryngo had varied, less pronounced, health properties. Accounts of its hypoglycaemic effects are actually supported by animal studies. Extracts of the aerial parts of E. creticum confirmed their hypoglycaemic effect in rat models(Reference Twaij, Abdel-Jalil and Ibrahim54). Similarly, reports regarding its anti-poisonous property have been previously tested. In fact, the leaf extract from E. creticum possessed potent antidote activity(Reference Alkofahi, Sallal and Disi55). As for claims on its blood properties, further analysis of this plant might clarify this effect.
Akkoub
Traditionally, G. tournefortii is known for its hypoglycaemic, laxative properties(Reference Al-Khalil17, 34, Reference Lev-Yadun and Abbo56, 57). Commonly known as ‘Akkoub’, G. tournefortii was reported mainly as a nutritious food by our informants. Nutrient analysis per 100 g of raw Akkoub highlighted its abundance in Ca (642 mg) and Fe (2·79 mg)(Reference Turan, Kordali, Zengin, Dursun and Sezen11).
Conclusion and future prospects
By comparison with previous scientific literature, the present results either add to the previous body of knowledge or report new findings that it is hoped will set the stage for further experimental investigations into these plants’ properties and highlight them as sources for widespread use and development. The investigated plants are renowned for their edible uses among informants in north-eastern Lebanese communities. Each plant has health and medicinal properties that add to its value for the participants and these properties are supported by scientific evidence. The plant parts used for food or for health and medicinal benefits are mostly the same, and the consumption of the plants in both cases follows a similar pattern. Thus the therapeutic effects of the plants can be derived from normal consumption as food. The fact that the field work was conducted in the summer instead of the spring season is a limitation to our study. Had it been in the spring, we would have been able to measure the quantities reported by the informants, since the plants were available in the wild and the informants were willing to go with us to the field.
Nevertheless, our findings highlight the importance of these six species of WEP for local diet and health, and support efforts for promoting the conservation and use of these specific plants, and WEP in general, within rural communities.
Another crucial finding of our study is that traditional knowledge within these communities is vanishing. When asked about persons knowledgeable in plants and their properties, inhabitants of the villages said that such informants had either died without transmitting their knowledge to their children, or that this topic does not interest people anymore and thus the knowledge is becoming scarce and forgotten with time.
Therefore, there is an urgent need to conserve this knowledge, record it and disseminate it within the communities.
The current project serves as a preliminary study in only one region of Lebanon. Rich ethnobotanical knowledge in a diversified, albeit small, country such as Lebanon warrants future in-depth ethnobotanical research in various communities. Similar studies in other Lebanese rural communities are encouraged to capture the diversity of the local knowledge within and between different communities. Focus groups with various community members would also help in identifying plants that are valuable to the communities and that serve as potential resources for future investigations.
Acknowledgements
We would like to acknowledge Canada’s International Development and Research Centre for its funding of the present study. There are no conflicts of interest to report. Z.J. contributed to data collection and analysis; T.J. contributed to data analysis and write-up; S.T. contributed to write-up; and M.B. was responsible for data collection, data analysis, write-up and project supervision. We are indebted to all contact persons and informants for their time and hospitality during our stay in the villages. Without their help, this project would not have seen the light.
