Enzymatic Modification of Arabinoxylans from Soft and Hard Argentinian Wheat Inhibits the Viability of HCT-116 Cells

Abstract

Dietary fiber plays an important role in the prevention of colorectal cancer, and arabinoxylans are an important source of this in grains, with some studies reporting the inhibition of cancer cell growth. However, very few studies have been conducted on this, and most previous studies have used oligosaccharides derived from arabinoxylans of specific molecular weight. The aim of this work is to extract, isolate, and analyze arabinoxylans from two different Argentinian genotypes of wheat (hard and soft) and study if they have the capacity to decrease the cellular viability of a colon cancer line (HCT-116). To determine whether the molecular size influences the inhibition of HCT-116 cell viability, specific hydrolysis was performed with endoxylanase, and the cells were exposed to the hydrolyzed arabinoxylans. The arabinoxylans treatment resulted in HCT-116 cell viability of 74%for the soft genotype and 64% for the hard genotype in comparison to nontreated cells. Hydrolyzedarabinoxylans result in HCT-116 cell viability of 68% for soft and 36% for hard genotypes (the lowest IC50 values) compared to nontreated cells. More importantly, no decrease after the arabinoxylans treatment was observed in the viability of murine noncancer cells known to rapidly respond to polysaccharide presence. The arabinoxylans from hard wheat showed more disubstituted xylose and α-1,2/α-1,3 linkages than the arabinoxylans from soft wheat, the possible cause for showing the best in vitro biological effect. The results showed other beneficial effects than the prebiotic ones and support the use of enzymatic treatment to increase the biologicalimpacts of arabinoxylans.