Bromelain Hydrolysis Modified the Functionality, Antioxidant, and Anti-Inflammatory Properties of Hempseed (Cannabis sativa L.) Protein Isolated at pH 12

Abstract

Hempseed (Cannabis sativa L.) is currently being investigated for its health-promoting properties acting as antioxidant and anti-inflammatory agents. Here, we present a modified protein isolation method of producing hempseed protein isolate from industrial hempseed hearts (HPI-12) using pH 12. In addition, bromelain was used to hydrolyze HPI-12 (BHPI-12) to determine the effect on functionality and bioactivity. HPI-12 is a rich source of essential amino acids with low protein solubility, effective in reducing 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals without oxygen radical antioxidant capacity (ORAC). Further, HPI-12 reduced pro-inflammatory IL-6 and TNF-α cytokines in lipopolysaccharide-induced inflammation in THP-1 macrophages. Upon hydrolysis, protein solubility was improved accompanied by modified water-and oil-holding capacities. BHPI-12 was more effective at quenching DPPH radicals with improved ORAC. BHPI-12 showed an improved ability to reduce IL-6. We report for the first time the ability of both HPI-12 and BHPI-12 as potential functional food ingredients with antioxidant and anti-inflammatory activity.