To obtain a scientific basis of the use of plant-derived preparations by many rural people in Cameroon, for their primary health care needs in the treatment of diseases such as cancer. The antiproliferative effect of 11 plants methanol crude extracts on four cancer cells using sulforhodamine-B assay and their antioxidant activities using 1-diphenyl-2-picrylhydrazyl radical and nitric oxide radical scavenging ability were investigated. The Ekebergia senegalensis (E. senegalensis) and Protea elliotii (P. elliotii) extracts were selected based on their antioxidant and anticancer activities, and partition in hexane, dichloromethane, ethyl acetate, butanol and methanol was done. Each fraction was submitted to antioxidant and anticancer activities, and the effect of the dichloromethane fraction (the most antiproliferative fraction) on NCI-H460 cell cycle was determined by flow cytometry. The most antiproliferative substances were found for the extracts from E. senegalensis, P. elliotii, Terminalia macroptera and Vitellaria paradoxa. Whereas the most antioxidant substances were found for the extracts from Cissus populnea, E. senegalensis, P. elliotii, Terminalia macroptera, Vitellaria paradoxa, and Gardenia aqualla. Dichloromethane fraction of P. elliotii was found to be highly antiproliferative to NCI-H460 cancer cells and showed S phase arrest cell cycle progression. Ethyl acetate n-butanol and methanol fractions showed quite strong antioxidant activity for both E. senegalensis and P. elliotii, as compared to that of gallic acid. Overall, the antiproliferative and antioxidant activities of some of the extracts lend some support to their use in the traditional medicine of Adamawa Region, Cameroon to treat cancer.

Gardenia aqualla a plant of the Rubiaceae family is being used extensively in Africa, particularly in Cameroon as an herbal medicine. Therefore it is necessary to have knowledge of the constituents of the plant of our native species. Thus, the aim of the present study was to investigate chemical constituents of this herbal medicine. Nine compounds, including one alkane, n-Nonacosane (1), two aliphatic alcohols n-heptatriacontanol (2) and n-Docosanol(3), one fatty ester, Heptadecyl heptacosanoate (4), two sugars, D-mannitol (5) and D-mannitol acetate (6), and a mixture of three phytosterols, β-sitosterol (7), stigmasterol (8) and fucosterol (9), have been isolated and purified from the stem barks of Gardenia aqualla Stapf & Hutch. Their structures were elucidated using spectroscopic analyses, including 1D and 2D NMR and ESI-MS. The fatty acid ester, heptadecyl heptacosanoate (4) is reported here for the first time. All the isolated compounds were tested for their antimicrobial activities against four Gram negative bacteria (Salmonella Typhimurium ATCC6539, Pseudomonas aeruginosa ATCC9721, Escherichia coli, and S. Typhi) and four yeasts (Candida albicans ATCC9002, Candida parapsilosis ATCC22019, Candida krusei and C. albicans).

An aliphatic alkene namely pentapentacontene (4) was isolated for the first time from a natural source, Gardenia aqualla, along with fourteen other compounds including nonacosanol (1), tetratriacontanol (2), octatriacontanol (3), β-sitosterol (5) and stigmasterol (6), daucosanol (7), ursolic acid (8), uvaol (9), 3β,19α,23β,24α-tetrahydroxyurs-12-en-28-oic acid (10), lupenone (11), oleanolic acid (12), vanillin (13), vanillic acid (14) and D-mannitol (15). α-glucosidase inhibitory assay revealed that MeOH and EtOAc extracts of leaves had the best activity with IC₅₀ of 9.65 and 20.03 µg/ml respectively. All the tested compounds showed dose dependent inhibition of α-glucosidase and some of them were found to be comparable to acarbose. Compound 10 was the most potent with IC₅₀ = 1.72 μM. It also showed the most interesting antibacterial activity, against the isolate strain of S. typhi and P. aeruginosa and also exhibited the most significant antifungal activities against all the tested yeasts. Graphical Abstract

Aims: The aim of the present study was to evaluate the total phenolics and flavonoids content of stem barks of Vitellaria paradoxa C. F. Gaertn., and identify its main chemical constituents. Methodology: V. paradoxa stem barks were extracted by maceration with methanol. Preliminary phytochemical screening was performed on the crude methanol extract (CME). Besides, total polyphenols contents (TPC) and total flavonoids contents (TFC) contents were also evaluated using the Folin-Ciocalteu method and complexation with aluminum chloride respectively. The antioxidant activity was evaluated by DPPH (2.2-diphenyl-1-picrylhydrazyl) and FIC (ferrous ion chelating) assays. Chromatographic isolation of the crude methanol extract (CME) followed by the spectroscopic identification of the isolated compounds was performed adopting 1D NMR and MS techniques. Results: All the compounds tested were found to be present in the CME of V. paradoxa stem barks. The extract was found to be rich in phenolics (18.48 ± 1.43 mgGAE.g^-1) and flavonoids (3.98 ± 0.44 mgGAE.g^-1). The CME showed high antioxidant activity as DPPH free radical scavenging and a low FIC activity. A new ursane type-triterpenoid named vitellaric acid (4) along with four known compounds (+)-catechin (1), (-)-epicatechin (2), betulinic acid (3a), and bassic acid (3b) were isolated from CME. Conclusion: The results of preliminary phytochemical screening of the leaf extracts revealed the presence of phytochemicals which could be used as medical regimens. The study provides scientific evidence for the use of V. paradoxa stem barks for the treatment of diseases mainly those associated with oxidative stress due to reactive oxygen species. Results yield a new addition to the chemical literature of V. paradoxa, in addition it increases the importance of NMR and MS techniques in structure elucidation.