Enzymatic and non-enzymatic bioactive compounds, and antioxidant and antimicrobial activities of the extract from one selected wild berry (Rubus coreanus) as novel natural agent for food preservation

Abstract

This work aimed to evaluate antioxidant and antimicrobial activity and action of selected wild berry (Rubus coreanus) for utilization. Wild berry was detected with rich non-enzymatic antioxidants (carotenoid, flavonoid, phenolic, anthocyanin, glutathione and ascorbic acid), and high activity antioxidant enzymes (superoxide dismutase, peroxidase, catalase, glutathione peroxidase and ascorbate peroxidase). Berry extract showed good radical scavenging capacity with low EC50 values of ABTS, DPPH, reducing power, ferric reducing antioxidant power, oxygen radical absorbance capacity and total antioxidant capacity (6.25, 8.16, 6.13, 3.25, 8.75 and 6.31 μg/mL respectively), high scavenging effect for •OH, O2•− and H2O2 at 100 μg/mL (95.28, 96.55 and 99.57%, respectively), and good potential to control foodborne pathogens. Antibacterial action was conducted on temporal changes for antibacterial curve, content leakage, oxidative stress, protein carbonyl, and respiratory-metabolic enzymes in Salmonella enteritidis exposed to berry extract at different concentrations (1/2-2 × MIC) and times (0–24 h), revealing that berry extract could act as an inducer for oxidative stress of S. enteritidis, causing cell structure damage and metabolic capacity deficiency. All findings indicated that wild berry could be as natural source of antioxidant or antimicrobial.