Baijiu vinasse as a new source of bioactive peptides with antioxidant and anti-inflammatory activity

During production in Chinese baijiu fermentation process, huge amounts of the by-product vinasse are generated and generally utilized as low-value animal feed. We applied alkaline extraction in combination with ultra-sonication to recover vinasse proteins, which were then hydrolyzed by complex protease Corolase PP for 8 h to obtain peptide fractions (VPH-1, -2, -3) displaying high DPPH radical scavenging activity. VPH-3 ( < 3 kDa) separated by ultrafiltration had EC50 values lower than those of VPH-1 and -2 for reactive oxygen species (ROS) and reactive nitrogen species (RNS) radicals, and significantly inhibited production of NO and pro-inflammatory cytokines in LPS-stimulated RAW264.7 macrophage cells. Active peptides and their amino acid sequences were identified by LC-MS/MS analysis, and five synthesized peptides (particularly KLPDHPKLPK and VDVPVKVPYS) displayed strong anti-inflammatory activity at concentration 0.25 mg/mL. These findings will be useful in future commercial development of baijiu vinasse, including application as a new source of bioactive peptides.

Automated summary

By utilizing alkaline extraction and ultra-sonication to recover proteins from baijiu vinasse, and hydrolyzing them with Corolase PP, peptide fractions with high DPPH radical scavenging activity were obtained. VPH-3, especially under 3 kDa after ultrafiltration, exhibited lower EC50 values for ROS and RNS radicals compared to VPH-1 and VPH-2, and showed significant inhibition of NO and pro-inflammatory cytokines in LPS-stimulated RAW264.7 macrophage cells. LC-MS/MS analysis identified active peptides with strong anti-inflammatory activity, such as KLPDHPKLPK and VDVPVKVPYS, at a concentration of 0.25 mg/mL. These findings suggest potential for commercial development of baijiu vinasse as a new source of bioactive peptides.