Ethnobotanical study of endemic and non-endemic medicinal plants used by indigenous people in environs of Gullele botanical garden Addis Ababa, central Ethiopia: A major focus on Asteraceae family

Ethnomedicine, antibacterial activity, antioxidant potential and phytochemical screening of selected medicinal plants in Dibatie district, Metekel zone, western Ethiopia

BACKGROUND

Medicinal plants play a major role in the delivery of healthcare, particularly among the rural population of Ethiopia. Plant extracts and their bioactive compounds have been utilized for the treatment of several diseases. This study was aimed at evaluating the antibacterial activity, antioxidant capacity, and phytochemical content of selected medicinal plants used in Dibatie district, western Ethiopia.

METHODS

Study plants were collected, shade dried, pulverized, extracted by maceration in 80% ethanol, and subjected to antibacterial, antioxidant, and phytochemical tests. Minimum inhibitory concentration (MIC) was determined using 96-well microplates and nutrient broth microdilution. Antioxidant activity was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Phytochemical screening was conducted using standard test methods.

RESULTS

The ethanolic extract of Polystachya steudneri Rchb.f. pseudobulbs was the most active against gram-negative Proteus mirabilis, Salmonella typhimurium, Klebsiella pneumoniae, Escherichia coli, and Shigella flexneri, with MIC values of 8 ± 0, 11 ± 5, 3 ± 1, 3 ± 1, and 2 ± 0 mg/mL, respectively. The ethanolic extract of P. steudneri was also the most effective against gram-positive Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus agalactiae, and Enterococcus faecalis, with MIC values of 8 ± 0, 8 ± 0, 3 ± 1, and 16 ± 0 mg/mL, respectively. Ethanolic extracts of Gnidia involucrata Steud. ex A.Rich. stems and roots were effective antioxidants, with respective 50% DPPH free radical inhibitory concentrations (IC50) of 168.68 and 181.79 µg/mL, followed by that of P. steudneri (IC50 = 203.11 µg/mL). The study plants contained alkaloids, anthocyanins, anthraquinones, cardiac glycosides, coumarins, flavonoids, phenols, saponins, steroids, tannins, and terpenoids.

CONCLUSIONS

This study confirmed the antibiotic, antioxidant, and phytochemical constituents of the investigated plants and suggested further investigations that may lead to bioactive lead compounds.

Overview of Ethnobotanical-Pharmacological Studies Carried Out on Medicinal Plants from the Serra da Estrela Natural Park: Focus on Their Antidiabetic Potential

The Serra da Estrela Natural Park (NPSE) in Portugal stands out as a well-preserved region abundant in medicinal plants, particularly known for their pharmaceutical applications in diabetes prevention and treatment. This comprehensive review explores these plants' botanical diversity, traditional uses, pharmacological applications, and chemical composition. The NPSE boast a rich diversity with 138 medicinal plants across 55 families identified as traditionally and pharmacologically used against diabetes globally. Notably, the Asteraceae and Lamiaceae families are prevalent in antidiabetic applications. In vitro studies have revealed their significant inhibition of carbohydrate-metabolizing enzymes, and certain plant co-products regulate genes involved in carbohydrate metabolism and insulin secretion. In vivo trials have demonstrated antidiabetic effects, including glycaemia regulation, insulin secretion, antioxidant activity, and lipid profile modulation. Medicinal plants in NPSE exhibit various activities beyond antidiabetic, such as antioxidant, anti-inflammatory, antibacterial, anti-cancer, and more. Chemical analyses have identified over fifty compounds like phenolic acids, flavonoids, terpenoids, and polysaccharides responsible for their efficacy against diabetes. These findings underscore the potential of NPSE medicinal plants as antidiabetic candidates, urging further research to develop effective plant-based antidiabetic drugs, beverages, and supplements.

Influence of socio-demographic factors on medicinal plant knowledge among three selected ethnic groups in south-central Ethiopia

BACKGROUND

The influence of socio-demographic variables was widely explored to evaluate their impact on indigenous and local ethnobotanical knowledge. However, the studies conducted in Ethiopia mainly focused on rural areas. They were limited to exploring and documenting ethnobotanical knowledge and the associated impacts of socio-demographic variables in rural-urban interface areas among ethnic groups. Hence, this study aimed to document plant-based indigenous and local ethnomedicinal knowledge and the associated impacts of socio-demographic variables among selected three ethnic groups in south-central Ethiopia.

METHODS

Ethnobotanical data were collected using semi-structured interviews with 189 key informants, floristic species inventories, and field observations. Quantitative approaches were used to evaluate the use values (UV) of the most important medicinal plants, the informant consensus factor (ICF), fidelity level (FL), relative popularity level (RPL), and rank-order priority (ROP). Statistical tests were applied to evaluate the influences of socio-demographic factors and associations between variables on local ethnobotanical knowledge across ethnic groups in different informant categories.

RESULTS

Statistical analysis revealed significant differences (p < 0.05) in the mean number of medicinal plants reported among age categories. There was also a positive association between the respondent's age and plant knowledge acquisition. Croton macrostachyus Hochst. ex Delile, Albizia gummifera C.A.Sm., Zingiber officinale Roscoe, Aloe macrocarpa Tod., Gymnanthemum amygdalinum (Delile) Sch.Bip., Calpurnia aurea (Aiton) Benth, and Allium sativum L. had the highest use values among ethnic groups. The highest informant consensus factor values were recorded for circulatory system disorders (0.68) followed by febrile illness and reproductive organ complications (0.66 each) across the three studied ethnic groups. The highest FL, RPL, and ROP values were noted for Lactuca inermis Forssk., Moringa stenopetala (Baker f.) Cufod., Withania somnifera (L.) Dunal, Allium sativum L., Citrus limon (L.) Osbeck, Ricinus communis L., Schinus molle L., Antiaris toxicaria (J.F.Gmel.) Lesch., Brucea antidysenterica J.F.Mill., Echinops kebericho Mesfin, Ocimum jamesii Sebald, Afrocarpus falcatus (Thunb.) C.N.Page, Searsia natalensis (Bernh. ex Krauss) F.A.Barkley, and Ricinus communis L. across ethnic groups in the study areas, which showed the conformity of knowledge on species curing potential and their prevalent uses.

CONCLUSION

The study revealed that the ethnic groups of Gedeo, Oromo, and Sidama have considerable indigenous and local ethnobotanical knowledge practices. Statistical analysis shown high variation in the acquisition of local ethnobotanical knowledge among age groups, which boosted our understanding of the effects of socio-demographic factors on the local ethnobotanical knowledge dynamics. Thus, this finding advocates for efforts to repair the observed generation gap via continued professional support and educating local communities to preserve traditional knowledge and practices through systematic documentation.

A review of the traditional uses, phytochemistry, pharmacology, and clinical evidence for the use of the genus Alchemilla (Rosaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Alchemilla L. (lady's mantle) comprises 1000 species, of which more than 300 have been characterized from Europe. Notably, as folk medicines, Alchemilla species have long been prescribed for the treatment of dysmenorrhea, pruritus vulvae, menopausal complaints, and related diseases in women. This review summarizes the traditional uses, highlights promising plant species, and focuses on phytochemical and biological studies to highlight future areas of research.

AIM OF THE REVIEW

This literature review aims to provide a comprehensive overview of Alchemilla species, covering their botany, traditional uses, phytochemistry, and biological and pharmacological activities, and to summarize the current research status to better understand the application value of Alchemilla plants in modern phytotherapy.

MATERIALS AND METHODS

The search strategy utilized the major thematic platforms Reaxys, Web of Science, Google Scholar, Scopus, ScienceDirect, PubMed, the USDA Plant Database and Kew Science (Royal Botanic Gardens) and was performed with the term Alchemilla. These platforms were systematically searched for articles published from 1960 to 2023.

RESULTS AND DISCUSSION

Alchemilla species, as members of the Rosaceae family, produce tannins, phenolic acids, flavonoids, anthocyanins, coumarins, triterpenes and violet compounds. Effort has been made with this comprehensive review of Alchemilla plants to highlight the recent developments and milestones achieved in modern phytochemistry and phytotherapy, underlaying a broad spectrum of the activities of these plants, such as antioxidant, anti-inflammatory, neuroprotective, antimicrobial, antiobesity, cardiovascular, anticancer, and wound healing effects.

CONCLUSIONS

An increasing number of studies on the plants in the Alchemilla genus have provided data about the main constituents and their importance in modern medicine. Both in vitro and in vivo studies have indicated that Alchemilla plants possess an extensive spectrum of biological activities. Regardless of the remarkable medical potential of Alchemilla extracts, clinical studies are limited and need to be performed to produce safer and less expensive plant-based drugs.

Ethnobotanical study of traditional medicinal plants used by the local people in Habru District, North Wollo Zone, Ethiopia

BACKGROUND

Ethiopia is a country located in the Horn of Africa, which combines richness in plant resources and cultures of human plant use. The people of Habru District of North Wollo Zone (Amhara Region, Ethiopia) have a long history of use of plant resources for various purposes including in traditional herbal remedy preparation and use. However, the district has not been adequately studied for its ethnobotanical resources and the associated knowledge. This study focused on human medicinal plants and their traditional uses in Habru District. The objective of the study was to document and analyze the plant species used by the local communities to treat human ailments along with the associated traditional knowledge and practices.

METHODOLOGY

The study was carried out in Habru District from June 2021 to December 2022. Ethnobotanical data were collected using semi-structured interviews, guided field walks, 13 focus group discussions (one at the district level and 12 at the kebele/subdistrict level) and market surveys. A total of 388 informants (250 males and 138 females) were selected from all 13 kebeles within Habru District using systematic random sampling, and 42 key informants were purposively selected. Descriptive statistics, preference ranking, direct matrix ranking, informant consensus factor and fidelity level were applied for data analysis.

RESULTS

The results provide insights into the medicinal plant diversity within Habru District, where 134 plant species in 110 genera and 54 families were documented, including 2 endemics, highlighting the district's significance in biodiversity conservation and healthcare delivery. Disease prevalence analysis showed that gastrointestinal and parasitic ailments (ICF = 0.85), febrile diseases (ICF = 0.84), and culture-related conditions exhibit high informant consensus factors. Remedy preparation involves various plant parts, predominantly leaves (47.3%), followed by roots (22.1%), fruits (7.0%), and seeds (5.8%). Freshly harvested plant parts were frequently used (58.2%), while 24.7% involved both dried and fresh parts. Oral application (47.3%) and topical use (31.8%) are the major routes of remedy administration. The marketability of medicinal plants was evident, with 16.4% of the species reported as marketable, including Terminalia brownii Fresen. Myrtus communis L., Ruta chalepensis L., Olea europaea L. subsp. cuspidata (Wall. & G.Don) Cif., Allium sativum L. and Capsicum annuum L. Multipurpose plants such as Solanum somalense Franchet. (91.3% FL), Ocimum lamiifolium Hochst. ex. Benth. (88.9% FL), and Verbascum sinaiticum Benth. (85.7% FL) exhibited notable healing potentials.

CONCLUSION

The current study underscores the intricate relationship between the local community and medicinal plants, emphasizing the importance of biodiversity conservation and health care and acknowledging the dynamic interplay between cultural heritage and ecosystem health. The results contribute to the development of sustainable conservation strategies, healthcare practices and the preservation of traditional knowledge, and highlight the interdependence of human societies and their natural environments. Community-based conservation initiatives with active participation of local communities are desirable for the conservation and sustainable use of medicinal plant species and their habitats. Raising public awareness about the sustainable harvesting and utilization of marketed medicinal plants (e.g., Terminalia brownii Fresen.) that are under threat is also important to ensure their availability for future generations and contribution to socioeconomic development.

Potential use of the Asteraceae family as a cure for diabetes: A review of ethnopharmacology to modern day drug and nutraceuticals developments

The diabetes-associated mortality rate is increasing annually, along with the severity of its accompanying disorders that impair human health. Worldwide, several medicinal plants are frequently urged for the management of diabetes. Reports are available on the use of medicinal plants by traditional healers for their blood-sugar-lowering effects, along with scientific evidence to support such claims. The Asteraceae family is one of the most diverse flowering plants, with about 1,690 genera and 32,000 species. Since ancient times, people have consumed various herbs of the Asteraceae family as food and employed them as medicine. Despite the wide variety of members within the family, most of them are rich in naturally occurring polysaccharides that possess potent prebiotic effects, which trigger their use as potential nutraceuticals. This review provides detailed information on the reported Asteraceae plants traditionally used as antidiabetic agents, with a major focus on the plants of this family that are known to exert antioxidant, hepatoprotective, vasodilation, and wound healing effects, which further action for the prevention of major diseases like cardiovascular disease (CVD), liver cirrhosis, and diabetes mellitus (DM). Moreover, this review highlights the potential of Asteraceae plants to counteract diabetic conditions when used as food and nutraceuticals. The information documented in this review article can serve as a pioneer for developing research initiatives directed at the exploration of Asteraceae and, at the forefront, the development of a botanical drug for the treatment of DM.