New polyglucopyranosyl and polyarabinopyranosyl of fatty acid derivatives from the fruits of Lycium chinense and its antioxidant activity

•Isolation of new compounds from the fruits of Lycium chinense.•Four new compounds identified as oligosaccharide of fatty acids.•Study of antioxidant activities of isolated compounds.•The compounds were investigated for the antioxidant effects using three methods.

Four new compounds 3,4-dihydroxy benzoic acid 3-octadecanoyl-4-O-α-l-arabinopyranosyl (2a→1b)-2a-O-α-l-arabinopyranosyl-(2b→1c)-2b-O-α-l-arabinopyranoside (1), 2,6,10-trimethyl-n-dodec-2-en-1-oyl-1-O-α-l-arabinopyranosyl-(2a→1b)-2a-O-α-l-arabinopyranosyl-(2b→1c)-2b-O-α-l-arabinopyranosyl-(2c→1d)-2c-O-α-l-arabinopyranosyl-(2d→1e)-2d-O-α-l-arabinopyranosyl-(2e→1f)-2e-O-α-l-arabinopyranosyl-(2f→1g)-2f-O-α-l-arabinopyranoside (2), n-docos-9,12-dienoyl-α-d-glucopyranosyl-(2a→1b)-2a-O-α-d-glucopyranosyl-(2b→1c)-2b-O-α-d-glucopyranosyl-(2c→1d)-2c-O-α-d-glucopyranosyl-(2d→1e)-2d-O-α-d-glucopyranosyl-(2e→1f)-2e-O-α-d-glucopyranoside (3), β-d-glucopyranosyl-(2a→1b)-2a-O-β-l-arabinopyranosyl-(2b→1c)-2b-O-β-l-arabinopyranosyl-(2c→1d)-2c-O-β-l-arabinopyranosyl-(2d→1e)-2d-O-β-l-arabinopyranosyl-(2e→1f)-2e-O-β-l-arabinopyranoside (4) along with some know compounds, were isolated and identified from a methanol extract Lycium chinense fruits. Their structures were determined of the new compounds using one- and two-dimensional NMR spectroscopies in combination by IR, FAB/MS and HR-FAB/MS. The compounds 1–4 were investigated for the antioxidant potential using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, reducing power and the phosphomolybdenum activity and the results demonstrate that the compounds (2 and 3) has potential as a natural antioxidant whereas the compound (4) exhibited moderate activity and the compound (1) exhibited weak antioxidant activity.