The Extrusion Process as an Alternative for Improving the Biological Potential of Sorghum Bran: Phenolic Compounds and Antiradical and Anti-Inflammatory Capacity

Abstract

Approximately 80% of sorghum phenolic compounds are linked to arabinoxylans by ester bonds, which are capable of resisting the digestion process in the upper gastrointestinal tract, compromising their bioaccessibility and biological potential. The aim of this study was to evaluate the effect of the extrusion process on the content of phenolic compounds in sorghum bran and its impact on phenolic compounds and antiradical and anti-inflammatory capacity. Results revealed that the extrusion process increased total phenol content in sorghum bran compared to nonextruded sorghum, particularly for extrusion at 180°C with 20% moisture content (2.0222 ± 0.0157 versus 3.0729 ± 0.0187 mg GAE/g +52%), which positively affected antiradical capacity measured by the DPPH and TEAC assays. The percentage of inhibition of nitric oxide (NO) production by RAW cells due to the presence of extruded sorghum bran extract was significantly higher than that of nonextruded sorghum bran extract (90.2 ± 1.9 % versus 76.2 ± 1.3 %). The results suggest that extruded sorghum bran could be used as a functional ingredient and provide advantages to consumers by reducing diseases related to oxidative stress and inflammation.