Advancing urban ethnopharmacology: a modern concept of sustainability, conservation and cross-cultural adaptations of medicinal plant lore in the urban environment

Urban ethnopharmacology is rapidly advancing and gaining significant attention throughout the world. In this review, we have presented the potential of urban ethnopharmacology and medicinal plants from the anthropologist and religious viewpoints. Additionally, the emergence and the present status of urban ethnopharmacology throughout the globe have been critically reviewed.


Introduction
A confluence of anthropology, history, flow of traditional folklore through generations, palaeobotany, ethnomedicine and agronomy gave birth to the discipline of urban ethnopharmacology. Plant-based medicines have been popular prior to the arrival of modern synthetic drugs. The study of plants and plant-based products used by city and town dwellers is known as urban ethnopharmacology, as emphasized by the prefix 'urban'. In a nutshell, the complicated relationships between people and plants in towns and cities form the basis of urban ethnopharmacology Hurrell and Pochettino, 2014;Anand et al., 2019;Mohammed et al., 2021;Datta et al., 2021). Urban botanical knowledge encompasses the consumption criteria of selection and production of plant products as well as the role of such knowledge in conservation (Hurrell and Pochettino, 2014). Lately, urban ethnopharmacology has been given crucial recognition, because a number of these traditionally used species are now vulnerable or critically endangered. International migrations lead to the expansion of traditional knowledge. When migrants settle in new cities or towns, they continue using their traditional remedies despite the availability of allopathic medicines and other conventional drugs. These dynamics of change upon being introduced from other communities into the existing ethnopharmacological implementations are explored and scrutinized in urban ethnopharmacology (Ceuterick et al., 2008;Pieroni and Privitera, 2014).
The fact that the literature available in this field is limited as this knowledge has traditionally been transmitted orally from one generation to the next and the only literature available is in the form of vernacular trivial ethnographic publications is a major constraint on the inclusion of traditional medicine in public health care practices (Petkeviciute et al., 2010). Some researchers, like Jacques, Barrau and Villamar, even consider ethnopharmacology as a section of anthropology, completely denying its existence in Botany . Another limitation might be the study of only the economically important plants of particular regions by earlier ethnobotanists, vehemently omitting the plants that were found in that region but were utilized in other regions, a practice condemned by (Kroeber, 1920, Hurrell, 2014). An important feature of non-traditional botanical knowledge (Hurrell and Pochettino, 2014) is the availability of healthcare and other essential products to the underprivileged masses (Ocvirk et al., 2013;Vandebroek, 2013).
Intercultural medicine essentially involves 'practices in healthcare that bridge indigenous medicine and western medicine, where both are considered as complementary' (Mignone et al., 2007;Vandebroek, 2013). Cities are assumed to be systems where society and nature form a fused heterogeneous ecosystem within which synthetic and organic components are interrelated (Almada, 2010;Ladio and Albuquerque, 2014). Since ecology as a discipline flourished beforehand, it is important to analyse whether the order of anthropological usage of herbs matches with the predictions made by existing ecological theories and concepts, which can only be done if the ethnobotanical concepts and theories of various cultures are systematically recognized and developed into hypotheses that can be validated experimentally (Gaoue et al., 2017). One of the shortcuts is the usage of hybridization, where traditional medicine is reconstructed and integrated in different ways to form a product more compatible for urban markets . On the other hand, an important question arises: 'Who will get the commercial benefits, these individual migrant groups or researchers, where the concept of intellectual property rights (IPR) is to be considered?' (McGonigle, 2016). Some ethnobotanists consider children to be important preservers and informers of botanical knowledge, passing knowledge to each other, being remnants of practices no longer present in adults and trying newer species while playing in nature and interacting with the environment (Łuczaj and Nieroda, 2011), whereas another set of researchers believe the women as reservoirs of traditional botanical knowledge (TBK) (Voeks, 2007;Katiyar et al., 2012;Wayland and Walker, 2014). Urban ethnobotany, introduced lately as a terminology in modern ethnobotany, truly depicts the 'pluricultural contexts in the urban agglomerations' with its ostensible inclination to the traditional field work with a need for sustainable conservation of urban folklore. Earlier, only few works have been carried out on modern urban ethnobotany in Latin American and European contexts. The present review aims to comprehensively enumerate the practices of urban ethnopharmacology across the world with notes on sustainable utilization of medicinal plants and the inherent plurality of the cross-cultural adaptations of medicinal plant use by the urban people. This review, in true sense, is a piece

Methodology
To retrieve the relevant records, a literature review of multiple disciplines from 1922 to 2019 was performed. The search string included the term 'Urban' + 'Ethnopharmacology', which was searched in Google Scholar, PubMed-NCBI, SpringerLink, Nature Publishing Group and other scientific databases. A detailed analysis of the articles presented in the references section was performed. Species names were checked against The Plant List 1.1 (2013), and family names follow the Angiosperm Phylogeny Group IV (Chase et al., 2016). All figures were constructed with the help of Microsoft Word, Autodesk or Sketchbook or were hand drawn. All tables and graphs were constructed by Microsoft Word and PowerPoint.

Through the eye of an anthropologist: the cross-cultural nature of urban ethnopharmacology
A unique aspect of urban ethnopharmacology is its pluricultural character. Pluriculturalism is a concept where individual identities result from participating in different cultures (Martínez et al., 2006). Multiculturalism is a theory where a community comprises of several ethnic groups, which may or may not have interactions. Pluriculturalism is based on the different interactions between these ethnic groups and new knowledge evolving from this exchange of values, traditions and resources. Multiculturalism forces uniformity and consistency and pluriculturalism allows for fluidity. Rural and small ethnic groups, who remain isolated from each other in their original habitats, tend to interact when they settle in urban areas (Fig. 1).
These migrations lead to pluralism or the doctrine of multiplicity (Schneider, 2007), which is the co-existence of ideas and principles. Conflict of ideas creates more ideas and hence confluence and conflict of knowledge creates more knowledge. Therefore, contrasting ethnopharmacology leads to the advancement of ethnopharmacology and drug delivery. Historical events sometimes influence the propagation of ethnopharmacology as well. For example, an increased trend of using medicinal plants was seen in Europe during the aftermath of World War II as a result of the scarcity of resources . Unani medicine was developed by Khalif Harun Al Rashid and Khalif Al Mansur by translating Greek and Sanskrit works (Dahanukar and Thatte, 1997). Similarly, Indo-Aryan migration led to the development of Vedic culture resulted in Ayurveda (Childe, 1996). Greek rational medicine reached its summit when it travelled to Egypt (Longrigg, 2013). Garlic [Allium sativum L. (Amaryllidaceae)], a medicinal plant widely used in India for cardio-vascular disorders and lowering cholesterol, was found in the tombs of Egyptian pharaohs and Greek temples, used against respiratory disorders in Rome, flu in America, plague in Europe and for digestion in China and Japan. (Gebreyohannes and Gebreyohannes, 2013;Alqethami et al., 2017). The medicinal use of Neem [Azadirachta indica A. Juss. (Meliaceae)] started in China when Bhogar Sidhdhar travelled from India to teach in China (Kumar and Navaratnam, 2013). These historical studies clearly show that plant medicine blossomed due to intercultural interactions and has its roots in major anthropological events of the past. Archaeological evidence even showed that botanical products and cereal foods were consumed by prehistoric men (Day, 2013;Valamoti et al., 2019) and selective consumption of plants by monkeys were interestingly similar to the ones used by humans (Weiner, 1980) demonstrating the origins of ethnopharmacology even beyond human origins. The synthesis of these compounds by plant species were itself a result of interactions with microbes, pests and herbivores (Bhattacharya, 2014).

Urban ethnopharmacology: emergence and present status throughout the globe
In the past few decades, the ethnobotanical field studies proliferated, especially in the developed countries to cope with the increasing demands of population expansion (Pieroni and Privitera, 2014). All studies included selection of a specific site of study, its detailed description including its geography, geology, ethnic background, ecology, edaphology, pedology, history, etc., description of sampling methods, proper interviews conducted with the participants, scientific identification of the species involved and data analysis by statistical methods including comparison with previous data (Cunningham, 2001;de Albuquerque and Hurrell, 2010;de Medeiros et al., 2013;Akbulut and Bayramoglu, 2014;Albuquerque et al., 2014;Conde et al., 2014;Pieroni and Privitera, 2014;Akbulut, 2015;Taylor and Lovell, 2015) or with the help of bioinformatics (Torre et al., 2012;Quave et al., 2012;Lagunin et al., 2014) The questions addressed are as follows: • How TBK accounts for sustainability and selection? • What are the roles of a specific species or genus in a society or community? • Evaluation of this knowledge for satisfying community needs.
These studies prevailed across the globe. A brief account of the ethnobotanical literature has been given in the Supplementary Table 1, where the main families and species uses have been described.

Urban ethnopharmacology in north and south American countries
A large number of South American literatures, especially from Brazil, were found regarding the use of plants as alternative medicine in urban areas. Extensive studies have been done in a number of South American cities like Petrópolis, Nova Friburgo, Rio Claro, Abaetetuba, etc. (Hurrell et al., 2015). This shows the importance and preservation of traditional knowledge among the urban population. However, in spite of these practices, ethnobotanical knowledge was found to be inversely proportional to financial status and education in Brazil (Arenas et al., 2013) drawing attention to its conservation and widespread awareness. North America showed contrasting results. Limited jobs and lack of funding is a considerable limitation , and hence TBK mainly was under practice in some parts of Mexico (Saynes-Vásquez et al., 2016;Lara Reimers et al., 2019). Occasionally, children from privileged families having private insurance in the USA were seen using complementary and alternative medicine (CAM) as a supplement to conventional medicine (Barnes et al., 2008).  (Eichemberg et al., 2009;Amorozo, 2002). In the home gardens of Abaetetuba, a city in Pará state, Brazil, 124 species were identified, 17.6% of which was used for curing infectious and parasitic diseases. Hemigraphis colorata W. Bull (Acanthaceae) was used to treat haemorrhoids and ear infections; Justicia pectoralis Jacq. (Acanthaceae) for uterine infections; Justicia secunda Vahl for gastric ailments;  (Arenas et al., 2013;Pochettino et al., 2012). A graphical representation of these information is presented in Fig. 2.
In Mexico, herbal medicine is used by more than 90% of the population (Popoca et al., 1998).

Urban ethnopharmacology in Africa
Africa is a continent with a rich biodiversity and miscellaneous ethnic groups. Each ethnic group has their own knowledge and medicinal practices. As the regions developed and the urban and rural divisions became blurred, these traditions seeped into the urban populations (Oreagba et al., 2011). Several of these practices are now prevalent in cities (Amira and Okubadejo, 2007;Hughes et al., 2015). were used as anti-diabetic agents (Ouhaddou et al., 2014;Makbli et al., 2016;Barkaoui et al., 2017).

Urban ethnopharmacology in Australia
Australian urban people prefer using alternative herbal medicine along with conventional treatments for faster healing (Fisher et al., 2018). Around 48% of the overall population in Australia uses alternative medicine, a vast number of whom were urban and mostly educated women (MacLennan et al., 1996). CAM practisers are consulted by 28% urban women (Adams et al., 2011). In a study in 2002, it was found that 32% insured urban adults treat neuromuscular diseases with alternative medicine in Washington State (Lind et al., 2009). Some of these herbal medicines, like Ginseng, were self-prescribed (Steel et al., 2018). Prevalence of use of Chinese medicine again shows the cross-cultural nature of TBK (Sibbritt et al., 2013). According to a population survey conducted in the year 2007, in Victoria, 90% of the population believe medicinal plant usage is beneficial and 22.6% had used some herbs in their lifetime (Zhang et al., 2008). Tea [C. sinensis (L.) Kuntze (= Thea sinensis L., Theaceae)], A. vera and garlic were the most popular. Ginseng, Peppermint, Chamomile, Ginkgo, Senna, Valerian, Dandelion, Liquorice and St John's Wart were some of the other herbs identified (Zhang et al., 2008). However, as herbal treatment is becoming increasingly popular among the urban people and is falling under health insurance policies, the cost of treatment is escalating. Hence, soon like in the USA, herbal medicine might be a luxury of the rich and privileged even in Australia.

Yum Kaax: role of plants in religion
Since ages, plants and their products have been used as offerings in religious ceremonies (Kessler et al., 2013;Frazão-Moreira, 2016;Quiroz and van Andel, 2018) or have been worshipped as sacred deities, which play an important role in their conservation. Majority of these plants had medicinal values. The God-fearing nature of human beings obliged them to protect both domestic and wild varieties and hence these practices acted like gene banks (Child, 1993). From Adam and Eve's expulsion from the Garden of Eden resulting from an apple to the tree of Bodhi, different plant species are deep rooted in almost every religion and mythology persisting on Earth. Human beings, who otherwise are selfish and have no empathy for nature, shift to sustainable use or cultivation of these special botanicals since they have to continue these rituals for ages. In some cases, religious leaders also play a substantial role in shaping the mind of a population towards conservation needs. Harming or cutting such trees is considered to be a sin and hence it is an effective tool to involve locals in safe guarding nature. These groups not only restrict their own consumption of the plants but also prevent overuse or theft by outsiders. Sacred groves are thickets or woodlands bearing plants of religious significance to certain communities or might be locations of important historical or mythological events (Adeniyi et al., 2018;Mequanint et al., 2020). The significance and the factors responsible for degradation of sacred groves have been depicted in Fig. 4. There are more than 100 000 sacred groves around the world, mainly concentrated in India, Nepal, South America, Japan and parts of Africa, some of which serving even as micro biosphere reserves. A graphical representation of sacred groves of the world and a map of country-wise occurrence major sacred groves are presented in Figs 5 and 6, respectively. The paganism and polytheistic religions teach nature worship and hence are mainly involved in the maintenance of these groves. As education and financial stability lead to the development and thus degradation of religious and cultural values, people tend to forget the important and sacredness of these groves leading to their exploitation and negligence of conservation.

Plants in Christianity and Islam
For Monotheistic religions, i.e. the Abrahamic religions 'Nature' and hence trees 'continue to be a source of Evil'. Satan came in the form of a snake enticing Eve to take a bite from the apple [Malus domestica Borkh. (Rosaceae)] of the tree of wisdom, which ultimately led to the Original Sin. In Genesis 1.29, it is written that God has instructed man, 'See, I give you every seed-bearing plant that is upon all the earth, and every tree that has seed-bearing fruit; they shall be yours for food.' The Bible has references to more than 36 trees (Coder, 2011;Evans, 2014)     Islam, similar to Christianity, is another religion that believes in a single God and considers Nature to be opposite to God. There were many incidences in history where sacred groves were not protected by the Muslims (Campbell, 2005;Dafni, 2006). Many scholars also preached that trees can never be sacred (Dafni, 2011). In spite of all these prejudices, a number of trees have been mentioned in the Holy texts   (Table 1), particularly the Sidra al-Munahā or the sacred lote tree denoting the edge of the 7th heaven, cypress, olive, date and fig trees. Graveyards have a lot of trees and these grounds are considered as holy and entry might be restricted (Dafni, 2006).

Plants in Hinduism and Buddhism
Polytheistic religions value nature, hence Hinduism gives importance to considering trees as sacred beings. Nature worship is practiced as several trees are seen as Gods like Peepal, Banyan, banana, Ashoka and Neem. Majority of these plants have medicinal properties. Trees are worshipped as their products, help in healing and provide food and nourishment. A list of some of the species are described in Table 2. Trees like Tulsi are sometimes found in the majority of Hindu households since keeping them are as compulsory as keeping shrines. Several natural products are used in ritualistic practices or as offerings to deities. Apart from nature worship, several forests and groves are directly associated with mythological stories and hence entry is restricted and commercial overexploitation is forbidden. Hinduism also considers all beings as sentient and connected directly to Brahma, the creator (Framarin, 2014). They are also part of the 'Cycle of Death and Rebirth' (Hall, 2011) and are able to experience 'pain and happiness' (Dwivedi, 1990) and hence hurting them is considered to be unholy. There are also festivals where tree planting is a ritual and the trees are planted according to astrology (Coward, 2003;Haberman, 2013). Planting trees and conservation of groves are considered of high religious merit since groves and forests serve as religious prayer sites (Nath and Mukherjee, 2015;Sarma and Devi, 2015).
Buddhism is neither monotheistic nor polytheistic, rather than giving all control and power to single or multiple gods, it gives importance to humanity, self-control and spirituality. Harming any living being including plants is considered sinful. Several plants are associated with the life of Buddha and are considered to be holy (Table 3), partly because Buddhism emerged from Hinduism and some of the principles have been retained (Hrynkow, 2017) and obtaining the rest of it from animism beliefs of Shinto religion (Omura, 2004). Ashoka tree is associated with Buddha's birth and Peepal tree is the Bodhi tree. Furthermore, natural products are used as offerings and in other rituals by monks including some timber producing trees (Sahni, 2007;Upadhyay and Prasad, 2011).

12
The terms Ayurveda and herbal are so common that simply claiming a product as herbal or adding these terms as a prefix improves the appeal of the product and increases its market demand. Many people miss the goods' ingredient labels and businesses benefit from this. Therefore, the knowledge established by rural elders and sustained for generations have thus intensified capitalism. The privileged became wealthier and the scions of the original discoverers continued life in cages of deprivation (Verma, 2002). A plethora of biopiracy cases have occurred (De Werra, 2009;Dunagan, 2009;Efferth et al., 2016;Ageh and Lall, 2019) where patents had been secured but the aboriginal populations concerned were not provided reasonable remunerations (Shiva, 2007;Shiva, 2016). Numerous American companies had copyrighted A. indica A. Juss. (Meliaceae) (Sheridan, 2005;Hamilton, 2006;Porter, 2006) and Curcuma longa L. (Zingiberaceae) (Udgaonkar, 2002;Schuler, 2004), two species that were used in India since ages. In Texas, where the company RiceTec declared Indian Basmati rice as 'Americantype Basmati' and advertised it as its own invention, which was an example of both consumer misleading and biopiracy (Runguphan, 2004). This makes the potential use of these plant products illegal by members of the ethnic groups in that area, a phenomenon that directly challenges their livelihoods, totally beyond ethics and humanity. Scientists who patent these formulations justify their conduct by citing stronger benefits for the improvement of research and industrial applications such as drug discovery.
Nearly $5.4 trillion in royalties are tricked off every year from ethnic groups and tribes. Careful recording and maintenance by groups of these data or records could assist in preventing biopiracy, as in the case of turmeric in India. However, the best solution to this problem might be access to resources and advantage sharing. In short, it is the distribution of profits. Native tribes can patent their existing compositions and can then partner with corporations that, with the aid of branding and ambassadors, are involved in the production of raw materials and distribution of finished goods, but have to give a decent percentage of the revenue to the original inventors. In urban ethnopharmacology, IPR works as it gives exclusive rights, but the concept is reliant on collaborating. Bio-cultural legacy sees biodiversity and community as one and positions them in the category of collective rather than private ownership (Swiderska, 2006). The ethnic groups aid in the management and protection of natural resources with this approach. They are also able to avoid hunting, stealing and harm of resources by outsiders by making them guardians of the woods. However, they overexploit these tools as corporations get involved, contributing to their endangerment and rendering the ecological system vulnerable. This approach thus gives priority to preserving the whole and maintaining the balance of nature rather than individual plants.
Humans constitute an essential part of the planet. In the massive system called nature, all of us have respective roles. It is therefore our responsibility, as the most intelligent organisms, to manage and use these plant resources in sustainable ways for socioeconomic, cultural and economic growth. Thus, the line 'country roads take me home' may not necessarily be true since they often lead you towards new experiences and insights. Without human relationships, urban ethnopharmacology is nothing and thus if advanced nations persist with capitalizing developing countries, this might result in the disappearance of ancient medicinal and pastoral expertise. We should still realize that modernization needs the help of nature to suffice, but the reverse is contradictory.

Conclusions
Medicinal plant usage by urban people was seen in all continents; however, the trends have been different. In the Americas, herbal medicines were either a part of healthcare of the poor in the developing countries or are been used as a health supplement by the rich in the developed countries, where the costs of these products are very high. Generally, in countries like Brazil, TBK was inversely proportional to education and financial status. In USA, alternative medicine could only be afforded by the rich and there was a general negative attitude towards the effectiveness of traditional plant medicines among the urban people. In Europe, small ethnic groups or immigrant groups living in metropolitan cities like London have kept the rich knowledge of botanical medicine alive. Urban people of South and East Asian countries like China, India, Pakistan, Bangladesh, Korea, Japan, Indonesia, etc., are highly dependent on herbal medicines belonging to all sections of the society, whereas negligible literature was found about usage in North and Western Asia. Herbal medicine industries in these countries generate substantial revenue. The trend in Africa is the same as southern Asia. Australian urban well-educated and employed women depend on alternative and herbal medicines, some of which are selfprescribed. However, as these treatments are being insured and becoming popular, the cost of treatment is increasing. Hence, soon like in the USA, herbal medicine might be a luxury of the rich and privileged even in Australia. In areas where tradition, culture and religion are an important part of the society, sacred groves and plants were prevalent, and some of them were of medicinal importance, since healing agents for diseases are considered holy. This plays a dominant role in their conservation. Monotheism normally shows plants in a negative light but does play some role in conservation by designating some groves as sacred or of ritualistic importance. Polytheism is inspired by animism and hence nature worship is frequently practiced. As a result, sacred groves are frequent in countries practicing polytheistic religions. However, there are still ways to go to recognize the contribution of the ethnic people with proper practices of bio-prospecting, avoiding biopiracy and protecting the consumer from misleading. Government, Non-Governmental Organizations and corporate sectors must carefully acknowledge the traditional wealth and the people and share a decent percentage of the revenue generated from commercial and sustainable utilization of ethnomedicinal knowledge. supervised. All authors reviewed the manuscript and agreed before submission.