Antibiofilm and anti-inflammatory potential of lignans with collegial effect: Secoisolariciresinol diglucoside and sesamin as antimicrobial sources

Abstract

Linum usitatissimum (L.), the Flaxseed (FS) and Sesamum indicum (L.), the sesame seeds (SS) are rich sources of lignans, secoisolariciresinol diglucoside (SDG), and Sesamin (Sm), respectively. Synergistic effects of the SDG and Sm lignan samples were investigated in the present study, a first of its kind. The high performance liquid chromatography fingerprint identified the presence of SDG and sesamin in FS and SS. Antimicrobial activity of SDG+Sm combination by disc diffusion in opposition to Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus significantly arrests growth of the bacteria in comparison to independent use of SDG and Sm. Bacterial biofilm inhibition capacity of SDG+Sm imaged by confocal laser scanning microscopy revealed the loss of microcolonies. SDG+Sm could inhibit the 15-LOX and COX-2 enzyme at relatively lower concentrations. Furthermore, SDG+Sm quenched free radicals produced by Fenton’s reagent studied by DNA-protection assay indicating its robust antioxidant property in protecting the DNA. These results put together encourage the use of a combination of FS and SS seed lignans SDG+Sm in a wide range of applications as natural preservatives with pharmacological effects, such as anti-inflammatory agent and aid, in their promotion as nutraceuticals.