DNA damage protection against free radicals of two antioxidant neolignan glucosides from sugarcane molasses

BACKGROUND: Sugarcane molasses is a potential by‐product of the sugarcane manufacturing industry that is rich in antioxidant materials. The present study aimed to obtain antioxidative compounds from sugarcane molasses and to evaluate their ability to protect DNA from oxidative damage. RESULTS: Two neolignan glucosides were isolated from sugarcane molasses using bioassay and UV spectra monitoring‐guided fractionation. The compounds were elucidated as (7R,8S)‐dehydrodiconiferyl alcohol‐4‐O‐β‐d‐glucoside (1) and (7S,8R)‐simulanol‐9′‐O‐β‐d‐glucoside (2). Neolignan glucoside 2 protected against DNA damage caused by free radicals more effectively than did neolignan glucoside 1 (13.62 and 9.08 µmol L⁻¹ for peroxyl and hydroxyl radicals, respectively, compared to 48.07 and 14.42 µmol L⁻¹). Additionally, neolignan glucoside 2 exhibited superior DNA protection against free radicals compared with various known antioxidative compounds, including p‐coumaric acid, ferulic acid, vanillic acid and epigallocatechin gallate. CONCLUSION: The isolated neolignan glucosides from sugarcane molasses are able to protect DNA from oxidative damage caused by free radicals. This is the first identification of these two compounds in sugarcane molasses. The sugarcane molasses can therefore be used as potential nutraceutical preventative agents, and the findings may foster the utilization of this by‐product as a bioresource‐based product. © 2015 Society of Chemical Industry