Assessment of the phytochemical composition and antimicrobial properties of Tapinanthus bangwensis leaves hosted by the branches of Persea americana.

BACKGROUND: Medicinal plants represent a valuable source for new effective and safe antimicrobial drugs making them an alternative therapy. Existing antimicrobial agents are costly and mostly associated with possible side effects. The aim of the present study therefore, was to assess the antimicrobial property and phytochemical composition of hydroethanolic extract of Tapinanthus bangwensis leaves and its fractions. METHOD: T. bangwensis leaves (harvested from its host plant, Persea americana) was extracted by cold maceration with 70% ethanol and further fractionated with different organic solvents using the solvent partitioning method to obtain the crude extract, petroleum ether, chloroform, ethyl acetate and the resulting aqueous fractions. The phytochemical constituents of the extracts were screened and quantified. Also, the TLC of the extracts were analyzed to serve as a fingerprint. Using the agar diffusion and broth dilution methods, the antimicrobial properties of the extracts were assessed. RESULTS: The study showed that the hydroethanolic (70%) crude extract of T. bangwensis leaves and its fractions contain phenolic compounds, flavonoids, saponins, phytosterols and reducing sugars. The phytoconstituents were well extracted into the ethyl acetate fraction than the other fractions evidenced in the high levels (p < 0.0001) of saponins (66.47 ± 1.72% w/w), phenolic compounds (77.75 ± 1.06 mg/100 mg GAE) and flavonoids (44.34 ± 0.06 mg/100 mg QE) contents. From the antimicrobial studies, all the microorganisms tested exhibited varying degrees of susceptibility to the extracts with MIC values between 0.78 to 12.5 mg/mL. The crude extract of T. bangwensis leaves, its ethyl acetate and chloroform fractions also exhibited lethal antimicrobial activity with MLC between 6.25 to 50 mg/mL. CONCLUSION: The crude extract of T. bangwensis leaves and its fractions demonstrated antimicrobial properties against Escherichia coli, Staphylococcus aureus, Staphylococcus saprophyticus and Candida albicans, thereby representing a potential source of natural antimicrobial agent. Further study is required to identify and isolate antimicrobial compounds from the plant for the development of the natural bioactive antimicrobial agents.

Bridelia ferruginea Benth.; An ethnomedicinal, phytochemical, pharmacological and toxicological review.

Ethnopharmacological relevance: Bridelia ferruginea belonging to the family Euphorbiaceae, identified as an important commonly growing shrub, is used in traditional medicine for managing arthritis, dysentery, constipation, chronic diabetes, skin diseases, bladder and intestinal disorders, oral infections, thrush, bites and as an arrow poison antidote. This review aims at providing information on the traditional medicinal uses, pharmacological activities, phytochemistry and toxicity studies of Bridelia ferruginea to bridge the gap between traditional medicinal uses and preclinical studies on B. ferruginea and subsequently lead to the development of valued added medicines from B. ferruginea. Materials and methods: Data in this review were compiled using databases such as Google Scholar, Science Direct, Scopus, PubMed, Springer link, Elsevier and Taylor and Francis, articles from peer reviewed journals and other grey literature (short notes, book chapters, short communications) to access all the relevant information available on B. ferruginea. Results: B. ferruginea contains different phytochemicals including flavonoids, phenolics, phytosterols, triterpenes, saponins, alkaloids and cardiac glycosides. Gallocatechin-(4'-O-7)-epigallocatechin, 3,5-dicaffeoylquinic acid, 1,3,4,5-tetracaffeoylquinic acid and some derivatives of 3-methoxyflavone, such as quercetin-3-methyl ether, quercetin 3-,7,3',4'-tetramethyl ether, myricetin 3',4',5'-trimethyl ether, myricetin 3,3',4',5'-tetramethyl ether, myricetin and quercetin 3-O-glucoside specific flavonoids and biflavonoids like apigenin, kaempferol and glycosides of both have been isolated and further characterized from B. ferruginea. B. ferruginea has several pharmacologically beneficial properties including anti-inflammatory, anti-diabetic, antioxidant, antimicrobial, anti-infective, antipyretic, analgesic, diuretic and natriuretic activities. Conclusion: The wide distribution, traditional medicinal uses and wealth of phytochemicals present in B. ferruginea suggests that the plant can be useful in lead compound discovery. Although B. ferruginea has been widely studied, further studies on the mechanism of action, bioavailability, pharmacokinetics, toxicity and side effects in humans need to be investigated.