Further constituents from the bark of Holarrhena pubescens

Steroidal Alkaloids From the Apocynaceae Family: Their Isolation and Biological Activity

Steroidal alkaloids are derived from the steroid skeleton with one or two nitrogen atoms. They are widely distributed in tropical and subtropical regions and possess a range of biological activities. The structures of steroidal alkaloids are comparable to those of anabolic steroids, steroidal hormones, and corticosteroids, making them a valuable source for drug discovery. Taxonomically, steroidal alkaloids are limited in distribution to certain plant families, predominantly the Apocynaceae, Buxaceae, Solanaceae, and Liliaceae. This review highlights the steroidal alkaloids from the Apocynaceae family and their biological activities. The articles published from 1919 to 2021 were included in this review. A total of 163 steroidal alkaloids and 12 biological activities were reported from plant species belonging to the Apocynaceae family in this period. Of the 410 genera in the Apocynaceae, only 10 contain steroidal alkaloids. Although some alkaloids from the Apocynaceae family were also reported in the Buxaceae family, especially tetracyclic triterpenes with a pregnane side chain, most steroidal alkaloids can only be found in several genera of the Apocynaceae family.

Metabolic Diversity and Therapeutic Potential of Holarrhena pubescens: An Important Ethnomedicinal Plant

Holarrhena pubescens is an important medicinal plant of the Apocynaceae family that is widely distributed over the Indian subcontinent. The plant is extensively used in Ayurveda and other traditional medicinal systems without obvious adverse effects. Beside notable progress in the biological and phytochemical evaluation of this plant over the past few years, comprehensive reviews of H. pubescens are limited in scope. It has economic importance due to the extensive use of seeds as an antidiabetic. Furthermore, the plant is extensively reported in traditional uses among the natives of Asia and Africa, while scientifical validation for various ailments has not been studied either in vitro or in vivo. This review aims to summarize information on the pharmacology, traditional uses, active constituents, safety and toxicity of H. pubescens. Chemical analysis of H. pubescens extracts revealed the presence of several bioactive compounds, such as conessine, isoconnessine, conessimine, conimine, conessidine, conkurchicine, holarrhimine, conarrhimine, mokluangin A-D and antidysentericine. Overall, this review covers the ethnopharmacology, phytochemical composition, and pharmacological potential of H. pubescens, with a critical discussion of its toxicity, biological activities (in vitro and in vivo), the mechanism of action, as well as suggestions for further basic and clinical research.

Medicinal plants used by traditional healers for the treatment of malaria in the Chipinge district in Zimbabwe

ETHNOPHARMACOLOGICAL RELEVANCE

Because about 50% of the Zimbabwean population is at risk of contracting malaria each year, the majority of people, especially in rural areas, use traditional plant-based medicines to combat malaria. This explorative ethnobotanical survey was undertaken to document how malaria is conceptualized and diagnosed by traditional healers, and to record the medicinal plants used in the prevention and treatment of malaria, their mode of preparation and administration.

MATERIALS AND METHODS

The research was conducted in three villages in Headman Muzite׳s area and in Chiriga village. These villages are located in the Chipinge district in the Manicaland Province in Zimbabwe.Traditional healers were selected with the assistance of the headman of the Muzite area and a representative of the Zimbabwe National Traditional Healers Association. Semi-structured interviews were conducted with 14 traditional healers from four villages in the Chipinge district in Zimbabwe.

RESULTS

In total, 28 plants from 16 plant families are used by the healers who manage malaria with medicinal plants. The most cited plant is Cassia abbreviata Oliv. (Leguminosae) followed by Aristolochia albida Duch (Aristolociaceae) and Toddalia asiatica (L.) Lam. (Rutaceae). Roots (55.3%) are the most common part used. Most of the plant parts used to treat malaria are stored as dried powders in closed bottles. The powders are soaked in hot or cold water and the water extract is taken as the active medicine. The healers consider their medicinal knowledge as a spiritual family heritage. Only 25% of the healers refer the malaria patients that do not respond to their treatment to hospital - they believe evil spirits cause their remedies to failure and they would rather try a different plant or perform a cleansing ceremony.

CONCLUSIONS

Local knowledge of medicinal plants in the treatment of malaria still exists in all four villages surveyed and traditional healers appear to play an important role in primary health care services in this remote rural area in Zimbabwe. This explorative survey underscores the need to preserve and document traditional healing for managing malaria and for more future scientific research on the plants to determine their efficacy and their safety. This could improve their traditional anti-malarial recipes and might contribute to a better integration of Zimbabwean traditional medicine into the national health system in the future.

Thai ethnomedicinal plants as resistant modifying agents for combating Acinetobacter baumannii infections

Abstracts

Constituents of the leaves of Holarrhena pubescens

The leaves of Holarrhena pubescens yielded a new naringenin glycoside (1), together with naringin, naringenin 7-O-beta-D-glucoside, lupeol, lupeol beta-hydroxyhexadecanoate and ursolic acid. The structure of 1 was determined by spectral analysis.