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The chemical investigation of the aerial part of Abrus canescens led to isolation of a new triterpenoid glycoside named Canescensoside ( 1 ) and four known compounds including longispinogenin-3- O - β -D-glucuronopyranoside ( 2 ), β -sitosterol-3- O - β -D-glucoside ( 3 ), apigenin-7- O - β -D-glucopyranoside ( 4 ) and apigenin-7- O -[ α -L-rhamnopyranosyl-(1→3)- β -D-glucopyranoside] ( 5 ). Structures of compounds were assigned by interpretation of their spectral data, mainly 1D and 2D NMR, HRESIMS, and by comparison with the reported data. The MeOH extract, EtOAc and n -BuOH fractions as well as isolated compounds were tested for their antibacterial activities against four bacteria strains among which, two Gram-negative ( Pseudomonas aeruginosa ATCC 76110 and Escherichia coli ATCC 8739) and two Gram-positive ( Enterococcus faecalis ATCC 29212 and Staphylococcus aureus ATCC 25923) bacteria using the broth microdilution method. The MeOH extract and EtOAc fraction exhibited significant activities (MIC values ranging from 128 to 512  μ g/mL) against all the tested bacteria. Compounds 2 and 3 showed the lowest MIC values of 55.47 and 50.40  µ M, respectively.

From the whole plant of Brillantaisia owariensis P. Beauv, a new iridolactone, owariensisone (1) together with six known compounds (nepetin-7-O-glucoside, choline, sucrose, mannitol, xylitol, 1-O-palmitoyl-2-eicosanoyl-3-O-(6-amino-6-deoxy)-β-d-glucopyranosyl-glycerol) were isolated. Structures of these compounds were established by direct interpretation of their spectral data, mainly HR-TOFESIMS, 1-D NMR ((1)H and (13)C) and 2-D NMR ((1)H-(1)H COSY, HSQC, HMBC, NOESY, TOCSY and DOCSY) and by comparison with the literature.

Diarrhea continues to be one of the most common causes of morbidity and mortality among infants and children in developing countries. The aim of the present study was to evaluate the antibacterial and antioxidant activities of extracts and compounds from Ludwigia leptocarpa, a plant traditionally used for its vermifugal, anti-dysenteric, and antimicrobial properties. A methanol extract was prepared by maceration of the dried plant and this was successively extracted with ethyl acetate to obtain an EtOAc extract and with n-butanol to obtain an n-BuOH extract. Column chromatography of the EtOAc and n-BuOH extracts was followed by purification of different fractions, leading to the isolation of 10 known compounds. Structures of isolated compounds were assigned on the basis of spectral analysis and by comparison to structures of compounds described in the literature. Antioxidant activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and gallic acid equivalent antioxidant capacity (GAEAC) assays. Antibacterial activity was assessed with the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) with respect to strains of a Gram-positive bacterium, Staphylococcus aureus (a major cause of community and hospital-associated infection), and Gram-negative multi-drug-resistant bacteria, Vibrio cholerae (a cause of cholera) and Shigella flexneri (a cause of shigellosis). All of the extracts showed different degrees of antioxidant and antibacterial activities. 2β-hydroxyoleanolic acid, (2R,3S,2''S)-3''',4',4''',5,5'',7,7''-heptahydroxy-3,8"-biflavanone, and luteolin-8-C-glucoside displayed the most potent antibacterial and antioxidant properties, and these properties were in some cases equal to or more potent than those of reference drugs. Overall, the present results show that L. leptocarpa has the potential to be a natural source of anti-diarrheal and antioxidant products, so further investigation is warranted.