The non-polar components of two leguminoceae species Albizia adianthifolia (Schumach), and Pterocarpus angolensis (DC) were investigated. GC-MS analysis of the crude n-hexane and chloroform extracts together with several chromatographic separation techniques led to the identification and characterization (using NMR) of sixteen known compounds from the heartwood and stem bark of Albizia adianthifolia and Pterocarpus angolensis respectively. These constituents include, n-hexadecanoic acid (palmitic acid) 1, oleic acid 2, chondrillasterol 3, stigmasterol 4, 24S 5α-stigmast-7-en-3β-ol 5, 9,12-octadecadienoic acid (Z,Z)-, methyl ester 6, trans-13-octadecanoic acid, methyl ester 7, tetradecanoic acid 8, hexadecanoic acid, methyl ester 9, octadecanoic acid 10, tetratriacontane 11, 7-dehydrodiosgenin 12, lupeol 13, stigmasta-3,5-diene-7-one 14, friedelan-3-one (friedelin) 15, and 1-octacosanol 16. Using agar over lay method, the preliminary antimicrobial assay for the extracts was carried out against bacterial (E. coli, P. aeruginosa, B. subtilis, S. aueus) and a fungus/yeast (C. albicans) strains. The n-hexane and chloroform extracts of A. adianthifolia showed the best activity against E. coli with minimum inhibition quantity (MIQ) of 1 µg each while the remaining exhibited moderate-to-weak activity against the test microorganisms.

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The genus Banisteriopsis (Malpighiaceae) comprises 77 genera and 1,300 species. Despite efforts to provide detailed information about the chemical wealth of B. laevifolia, this article provides the identification and characterization of compounds from the ethanolic extracts of the leaves and flowers using advanced methodologies which include high-performance liquid chromatography coupled to tandem mass spectrometry, which contribute to the knowledge about compounds present in the genus Banisteriopsis. The dereplication aided by Global Natural Products Social Molecular Networking afforded the identification of seven compounds reported for this species for the first time. A mixture of two known flavonoids and a diterpenoid, 18-hydroxy-ent-halima-1(10),13-(E)-dien-15-oic acid, were isolated by conventional separation methods. The elevated 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity observed in some samples was attributed to either the type of extract, the presence of 3,4,5-trihydroxybenzoic acid, or the influence of the substitution pattern and the synergistic effect of the compounds present. Principal Component Analysis was applied to correlate mass spectrometry data with the antioxidant activity of the samples. The high diversity of metabolites found in this study and those which have been reported for Banisteriopsis strongly recommends further investigation into the chemical and biological properties of these species.

The dichloromethane extract of the cashew nuts from Anacardium occidentale was fractionated by rotation locular countercurrent chromatography aimed at discovering metabolites that could be useful as new models for photosynthesis inhibitors. The chemical fractionation afforded a complex mixture of anacardic acids, which upon catalytic hydrogenation yielded anacardic acid (1). Methylation of 1 via reaction with diazomethane afforded an ester 2. Both compounds were evaluated using polarographic approaches and fluorescence studies of chlorophyll a (ChL a). The in vitro assays informed the decision for the classification of 1 and 2 as Hill reaction inhibitors. Besides that, 1 inhibited the donor side of the PSII, while 2 acted as an energy transfer inhibitor. Therefore, this study is important for the development of herbicides.