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Background: Alstonia boonei, belonging to the family Apocynaceae, is one of the best-known medicinal plants in Africa and Asia. Stem back preparations are traditionally used as muscle relaxants. This study investigated the antispasmodic properties of Alstonia boonei Stem back and its constituents. Method: The freeze-dried aqueous Stem back extract of A. boonei, as well as dichloromethane (DCM), ethyl acetate, and aqueous fractions, were evaluated for their antispasmodic effect via the ex vivo method. Two compounds were isolated from the DCM fraction using chromatographic techniques, and their antispasmodic activity was evaluated. An in silico study was conducted by evaluating the interaction of isolated compounds with human PPARgamma-LBD and human carbonic anhydrase isozyme. Results: The Stem back crude extract, DCM, ethyl acetate, and aqueous fractions showed antispasmodic activity on high-potassium-induced (K+ 80 mM) contractions on isolated rat ileum with IC50 values of 0.03 ± 0.20, 0.02 ± 0.05, 0.03 ± 0.14, and 0.90 ± 0.06 mg/mL, respectively. The isolated compounds from the DCM fraction were β-amyrin and boonein, with only boonein exhibiting antispasmodic activity on both high-potassium-induced (IC50 = 0.09 ± 0.01 µg/mL) and spontaneous (0.29 ± 0.05 µg/mL) contractions. However, β-amyrin had a stronger interaction with the two proteins during the simulation. Conclusion: The isolated compounds boonein and β-amyrin could serve as starting materials for the development of antispasmodic drugs. [ABSTRACT FROM AUTHOR]

Context: Co-administration of amodiaquine with MAMA decoction (MD), an herbal antimalarial drug comprising the leaves ofMangifera indicaL. (Anacardiaceae), Alstonia booneiDe Wild (Apocynaceae), Morinda lucidaBenth (Rubiaceae) andAzadirachta indicaA. Juss (Meliaceae) was investigated. The practice of concurrent administration of herbal medicines with orthodox drugs is currently on the increase globally. Objective: The study was designed to investigate the possible enhancement of the antimalarial potency as well as possible herb–drug interaction resulting from concurrent administration of MAMA decoction with amodiaquine (AQ). Materials and methods: Combinations of MD with AQ were investigated in chloroquine (CQ)-sensitivePlasmodium bergheiNK 65 in varying oral doses (mg/kg) at: sub-therapeutic [MD30 + AQ1.25], therapeutic [MD120 + AQ10] and median effective [MD40 + AQ3.8], using chemosuppressive and curative antimalarial test models. Secondly,P. bergheiANKA (CQ-resistant)-infected mice were orally treated with MD 120, 240, [MD120 + AQ10] and [MD240 + AQ10] mg/kg, using both models. The survival times of mice were monitored for 28 d. Results: ED50values of MD and AQ were 48.8 and 4.1 mg/kg, respectively. A total parasite clearance of CQ-sensitiveP. bergheiNK65 was obtained with the therapeutic combination dose in the curative test giving an enhanced survival time. In CQ-resistantP. bergheiANKA-infected mice, [MD120 + AQ10] and [MD240 + AQ10] mg/kg gave comparable activities with AQ (10 mg/kg) in both models. Conclusion: The therapeutic combination dose gave total parasite clearance of CQ-sensitiveP. bergheiNK65, whereas none of the doses tested showed notable activity against CQ-resistantP. bergheiANKA. [ABSTRACT FROM PUBLISHER]

Abstract: The aqueous extract of Calotropis procera was evaluated for its spasmolytic effect using in vitro trachea smooth muscle chain of Guinea-pig. The extract (50, 100 and 200 μg/ml) showed a dose-dependent relaxant activity probably exhibited through the direct relaxant action on the smooth muscle. [Copyright &y& Elsevier]

The coronavirus disease 2019 (COVID-19) pandemic is caused by an infectious novel strain of coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which was earlier referred to as 2019-nCoV. The respiratory disease is the most consequential global public health crisis of the 21st century whose level of negative impact increasingly experienced globally has not been recorded since World War II. Up till now, there has been no specific globally authorized antiviral drug, vaccines, supplement or herbal remedy available for the treatment of this lethal disease except preventive measures, supportive care and non-specific treatment options adopted in different countries via divergent approaches to halt the pandemic. However, many of these interventions have been documented to show some level of success particularly the Traditional Chinese Medicine while there is paucity of well reported studies on the impact of the widely embraced Traditional African Medicines (TAM) adopted so far for the prevention, management and treatment of COVID-19. We carried out a detailed review of publicly available data, information and claims on the potentials of indigenous plants used in Sub-Saharan Africa as antiviral remedies with potentials for the prevention and management of COVID-19. In this review, we have provided a holistic report on evidence-based antiviral and promising anti-SARS-CoV-2 properties of African medicinal plants based on in silico evidence, in vitro assays and in vivo experiments alongside the available data on their mechanistic pharmacology. In addition, we have unveiled knowledge gaps, provided an update on the effort of African Scientific community toward demystifying the dreadful SARS-CoV-2 micro-enemy of man and have documented popular anti-COVID-19 herbal claims emanating from the continent for the management of COVID-19 while the risk potentials of herb-drug interaction of antiviral phytomedicines when used in combination with orthodox drugs have also been highlighted. This review exercise may lend enough credence to the potential value of African medicinal plants as possible leads in anti-COVID-19 drug discovery through research and development. [ABSTRACT FROM AUTHOR]

Purpose: To examine the state of herbal medicines research and development (R&D) outputs in universities, research institutes and pharmaceutical manufacturing firms in Nigeria. Methods: Questionnaires were administered to core researchers in the above-mentioned research organizations using purposive and convenient sampling technique. The questionnaire elicited vital information on researcher's area of specialization, academic qualifications, state of research facilities and approach to herbal medicines R&D by the organization. Data were analyzed using appropriate statistical tools. Results: The study revealed that the researchers were highly qualified individuals who specialized in eight distinct areas. Research facilities were in varying degrees of deterioration. Major R&D activities were incremental or modification of products/process (58 %), continuous improvement of R&D programs (23 %), radical process/product development (20 %), and creative (11 %) and duplicative (7 %) efforts. Strategies to enhance herbal medicine R&D were increased funding (36.3 %), training of researchers (28.1 %), improvement in R&D infrastructure (18.6 %) and fostering public-private partnership (17 %). Conclusion: Herbal medicines R&D is not fully developed in Nigeria due to a myriad of fundamental challenges facing the key players. [ABSTRACT FROM AUTHOR]

The choice of extraction solvent is a significant consideration in ethnomedicine as optimal extraction could influence the bioactivity of the herbal medicinal product. This study investigated the possible influence of the choice of solvents (methanol and water) for extracting MAMA Powder (MP) against Plasmodium berghei -infected mice to optimize its antimalarial activity and for developing other pharmaceutical dosage forms. Aqueous and methanol extracts of MP, obtained through the decoction and soxhlet methods, respectively, were subjected to liquid chromatography-mass spectroscopy (LC-MS) for their respective fingerprints. The antimalarial activities of the methanol and aqueous extracts (12.5–100 mg/kg) were evaluated orally using the chemosuppressive test model on chloroquine-sensitive Plasmodium berghei -infected mice. The methanol extract was subjected to the established infection and prophylactic antimalarial tests with chloroquine (10 mg/kg) and pyrimethamine (1.25 mg/kg) as positive controls, respectively. The aqueous extract was investigated in chloroquine-resistant P. berghei using the chemosuppressive (12.5–800 mg/kg) and established infection (25–400 mg/kg) antimalarial models. The LC-MS fingerprints of both aqueous and methanol extracts revealed similar indole alkaloid contents. Chemosuppressive activity of the aqueous extract (75.3%) was significantly (p < 0.05) higher than the methanol extract (67.6%). In the chloroquine-resistant P. berghei infection experiments, the aqueous extract (400 mg/kg) exhibited significant parasite clearance (72%). The study concluded that the water extract with higher antimalarial activity could be optimized for chloroquine-resistant malaria and can thus facilitate the production of liquid and solid dosage forms. [Display omitted] • The liquid chromatography-mass spectroscopy fingerprints of the two extracts revealed similar profile of indole alkaloids. • Bioactivity was not enhanced with further purification of the methanol extract. • Water was a better solvent for extraction as the antimalarial activities of MAMA Powder was higher. [ABSTRACT FROM AUTHOR]

Background: The root and stem bark of Cassia sieberiana DC. (Caesalpiniaceae) and the root of Senna obtusifolia (Linn) Irwin and Barneby (Caesalpiniaceae), used for constipation in Nigeria, were assayed for laxative properties in male albino rats using the official senna leaf (Senna alexandrina Mill. family Caesalpiniaceae) as the reference standard. This is with a view to finding alternative laxative drug to official senna which is presently being imported into Nigeria from the United Kingdom., Materials and Methods: The mean percentage of wet faeces in rats, an indication of laxative activity, were obtained using established methods. The laxative activity was established at 500 mg/kg after the infusion of the drug was orally administered on male albino rats following established methods while a set of data was analyzed at 95 % confidence level., Results: At 500 mg/kg, Senna obtusifolia root gave about 45 % wet faeces while Cassia sieberiana root gave about 40 % wet faeces while at the highest dose of 700 mg/kg, they produced 60 % and 38 % wet faeces, respectively. At these two doses, the official Senna gave 50.6 % and 66 % wet faeces, respectively. Thus, S. obtusifolia and C. sieberiana roots exhibited 89 % and 80 % of the potency of S. alexandrina (the official drug), respectively. The analysis of variance revealed a significant statistical difference in the levels of wet faeces produced by rats dosed with C. sieberiana root., Conclusion: The results have shown that the roots of the two species could be developed as mild laxative drugs for children and pregnant women for whom the official senna will be contraindicated.