This study indicated that the isoflavones from soya beans could be considered as potential antioxidants or antimicrobials in the food, cosmetics and pharmaceutical industries. © 2017 Society of Chemical Industry.

A comprehensive phytochemical study of the chemical constituents of green vegetable soybeans resulted in the isolation of two new alkaloids, soyalkaloid A, 1, and isoginsenine, 2, together with four known ones, ginsenine, 3, (1S,3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid, 4, (1R,3S)-1-methyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid, 5, and indole-3-carboxylic acid, 6. The structures of compounds 1-6 were elucidated on the basis of spectroscopic and chemical analyses. All of the alkaloids were isolated from soybeans for the first time, and compound 1 was a new indole-type alkaloid with a novel carbocyclic skeleton. Their inhibitory activities on the proliferation of concanalin A-activated lymphocytes were assessed by CCK8 assay.

Ten compounds were isolated and identified from green vegetable soya beans, of which five are new triterpenoid saponins (1-5) and five are known compounds (6-10). The chemical structures of the five triterpenoid saponins (1-5) were elucidated to be 3β,24-dihydroxy-22β,30-epoxy-30-oxoolean-12-en 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl-(1 → 2)-β-d-glucuronopyranoside, 1; 3β,24-dihydroxy-22β,30-epoxy-30-oxoolean-12-en 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-(3″-O-formyl)-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, 2; 22-keto-3β,24-dihydroxy oleanane-12-ene 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-(3″-O-formyl)-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, 3; 3β,22β,24-trihydroxy oxyolean-18(19)-ene-29-acid 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, 4; and punicanolic acid 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, 5 from the spectroscopic data (IR, GTC/FID, HR-ESI-MS, and 1D and 2D NMR). The nitric oxide release inhibitions of compounds 1-10 in LPS-stimulated RAW264.7 cells were evaluated, and the data suggested that compounds 1, 2, and 5 might possess moderate anti-inflammatory activities, with IC values of 18.8, 16.1, and 13.2 μM, respectively.