Antibacterial prenylated stilbenoids from peanut (Arachis hypogaea)

Abstract

Stilbenoids are a class of secondary metabolites with a stilbene backbone that can be produced by peanut (Arachis hypogaea) as defence metabolites. Six monomeric prenylated stilbenoids, including the compound arachidin-6 (4), were isolated from extracts of fungus-elicited peanuts (Arachis hypogaea) using preparative liquid chromatography. Their structures were confirmed by MS n , HRMS and NMR spectroscopy and their antibacterial activity was evaluated against methicillin-resistant Staphylococcus aureus (MRSA). Similarly to other phenolic compounds, prenylated derivatives of stilbenoids were more active than their non-prenylated precursors piceatannol, resveratrol, and pinosylvin. Chiricanine A (6), a chain-prenylated pinosylvin derivative, was the most potent compound tested, with a minimum inhibitory concentration (MIC) of 12.5 µg mL-1. Arachidin-6 (4), a ring-prenylated piceatannol derivative, had moderate potency (MIC 50-75 µg mL-1). In conclusion, prenylated stilbenoids represent a group of potential natural antibacterials which show promising activity against MRSA. Highlights  New stilbenoid: arachidin-6, a ring-prenylated piceatannol derivative.  Antibacterial activity of purified prenylated stilbenoids assessed against MRSA.  Chiricanine A (MIC 12.5 µg mL-1) and other stilbenoids are active against MRSA.

Insights into the molecular properties underlying antibacterial activity of prenylated (iso)flavonoids against MRSA

“…Novel chemical scaffolds with different modes of action to currently used antibiotics are constantly being investigated 7 . Prenylated flavonoids and isoflavonoids, collectively termed as (iso)flavonoids, as well as stilbenoids, have shown promising antibacterial activity against clinically-relevant pathogens, including MRSA 8 , 9 . Prenylated phenolic compounds are a class of secondary defence metabolites produced by species of the Fabaceae family upon (a)biotic stress 10 .…”

Impact of Environmental Factors on Stilbene Biosynthesis

“…In accordance with their role as phytoalexins, peanut prenylated stilbenoids have been shown to accumulate upon challenge with microorganisms [142][143][144][145]149] and to possess remarkable antifungal activity [150][151][152]. Several recent studies have shown interesting therapeutic potential for peanut prenylated stilbenoids [135,136,153,154]. Prenylated compounds generally exhibit greater bioavailability than their non-prenylated counterparts, due to the increase in lipophilicity linked to the prenyl groups.…”

Toward Developing a Yeast Cell Factory for the Production of Prenylated Flavonoids

“…1,7−10 As a result of their health benefits, prenylated flavonoids are currently investigated as potential biopharmaceuticals and functional foods. Last but not least, prenylated (iso)flavonoids have also received interest because of their promising antimicrobial activity, 11−14 suggesting that they might also be used as food preservatives or antibiotics in clinical applications.…”