Mt Elgon is an ancient transboundary volcanic mountain found at the Kenya-Uganda boarder possessing high plant diversity. This study documents an updated checklist of the mountain's vascular plants obtained through random-walk field excursions and retrieval of herbarium specimen tracing back to 1900. We compiled 1709 species from 673 genera in 131 families. One new species of the family Cucurbitaceae was also reported. This checklist records respective habitat, habits, elevation ranges, voucher numbers and global distribution ranges of each species. Native and exotic species were also distinguished, where 8.4% of the total species in 49 families were exotic species. There were 103 endemic species, while 14 species were found to be both rare and endemic. IUCN conservation status revealed 2 Critically Endangered, 4 Endangered, 9 Vulnerable and 2 Near Threatened species. This study presents the first and most comprehensive plant inventory of Mt Elgon that will facilitate further ecological and phylogenetic studies.

Makaleyi görüntüle

Globally, food and medicinal plants have been documented, but their use patterns are poorly understood. Useful plants are non-random subsets of flora, prioritizing certain taxa. This study evaluates orders and families prioritized for medicine and food in Kenya, using three statistical models: Regression, Binomial, and Bayesian approaches. An extensive literature search was conducted to gather information on indigenous flora, medicinal and food plants. Regression residuals, obtained using LlNEST linear regression function, were used to quantify if taxa had unexpectedly high number of useful species relative to the overall proportion in the flora. Bayesian analysis, performed using BETA.INV function, was used to obtain superior and inferior 95% probability credible intervals for the whole flora and for all taxa. To test for the significance of individual taxa departure from the expected number, binomial analysis using BINOMDIST function was performed to obtain p -values for all taxa. The three models identified 14 positive outlier medicinal orders, all with significant values ( p p p p < 0.05). Anacardiaceae (5.163) had the highest R-value, while Fabaceae had the highest (28.72) regression residuals. This study presents important medicinal and food taxa in Kenya, and adds useful data for global comparisons.

Makaleyi görüntüle

Ethnopharmacological relevance Voluntary depigmentation, a very common practice in sub-Saharan Africa, often performed with pharmaceutical products diverted from their pharmacological use, may cause severe dermatological and systemic side effects. The present work aims at investigating whether and which herbs were used in Rwanda for similar purposes before the advent of the current depigmentation craze; this may give clues at herbal treatments possibly advantageous compared to current products. Material and methods Sixty-one traditional healers, mostly representatives of their associations, were surveyed by questionnaires for knowledge and practice of voluntary depigmentation. Recipes or plants used, plant parts, harvest area, preparation methods, dosage and route of administration were recorded. Most of the cited herbs were harvested with the help of traditional healers and identified by comparison with voucher specimens; herbal vouchers of the five most cited herbs were deposited in official herbaria. Results All surveyed traditional healers have knowledge of voluntary depigmentation; the population currently practicing do not recourse to their services but obtain bleaching products directly from the market. Traditional healers disclosed recipes prescribed or self-used (often by women) in their youth; others cited recipes are used to treat skin diseases with properties of "clarification", "black skin stain removal", in cases of hyperpigmentation, and/or "skin softening". Curiously, from the 28 recipes cited by traditional healers, all are mono-herbal preparations; most of the plants are mixed with butter for application to the skin. Conclusion Compared to other pathophysiological conditions, there is currently a very limited use of herbal preparations for depigmentation. Five herbs had a citation percentage equal or above to 50%, Brillantaisia cicatricosa Lindau (Acanthaceae), Chenopodium ugandae (Aellen) Aellen (Chenopodiaceae), Dolichopentas longiflora Oliv. (Rubiaceae), Protea madiensis Oliv. (Proteaceae) and Sesamum angolense Welw. (Pedaliaceae); in vitro experiments indicated a modulation of melanogenesis by these plant extracts, confirming the information obtained from traditional healers.

Makaleyi görüntüle

Ethnopharmacological relevance Traditional herbal medicines provide an interesting, largely unexplored source for the development of potential new drugs and skin-care cosmetics. Some herbal extracts are known to be inhibitors of melanin formation, sometimes more potent than the classical inhibitors, hydroquinone/arbutin or kojic acid, and are not associated with melanocytes cytotoxicity or mutagenicity. Such plants are used in traditional medicine in many countries, particularly in Africa, for skin lightening. Aim of the study To evaluate in vitro the ability of Rwandese medicinal plants, traditionally used for the treatment of skin (discoloration and attenuation of discolored spots), to modulate pigmentation and tyrosinase activity. Materials and methods Based on an ethnopharmacological survey, five herbs [Brillantaisia cicatricosa Lindau (Acanthaceae), Chenopodium ugandae (Aellen) Aellen (Chenopodiaceae), Dolichopentas longiflora Oliv. (Rubiaceae), Protea madiensis Oliv. (Proteaceae) and Sesamum angolense Welw. (Pedaliaceae)] were selected. Twenty-seven extracts, obtained by treating the herbs with increasing polarities solvents, were investigated for their effects on cell viability (MTT test) and on pigmentation: inhibition of the enzyme tyrosinase (colorimetry of reaction products, measurement of enzyme activity, TLC-autography; studies on crude cellular extracts obtained from normal melanocytes and on a mushroom tyrosinase) and measurement of melanogenesis by human melanoma cells. Results None of the tested plant extracts were cytotoxic on tested human melanoma cell lines, except for Dolichopentas longiflora (IC50 of leaves n-hexane extract, 4μg/ml for MM028 and 4.5μg/ml for MM001; IC50 of roots ethyl acetate extract, 0.8μg/ml for MM028 and 3.9μg/ml for MM001). Almost all extracts inhibited melanogenesis in a melanoma whole cells overall pigmentation assay, a model reflecting the entire cycle of melanogenesis. All the Protea madiensis extracts quite strongly inhibited melanogenesis and, surprisingly, one of the Dolichopentas longiflora leaves extracts was found to increase melanogenesis. These results were confirmed by the modulation of pigmentation reactions by crude cellular extracts obtained from normal melanocytes; interestingly, one of the extracts (Dolichopentas longiflora ethyl acetate extract) is even more active (61% at 500μg/ml) than kojic acid ( Conclusions Ethnopharmacological data represent an efficient approach to discover active herbs. Some of the selected medicinal plants clearly show potent tyrosinase inhibitions while one extract significantly increases cell pigmentation; one extract contains potent growth melanocytes inhibitors.

Makaleyi görüntüle