Screening for antioxidant and antibacterial activities of phenolics from Golden Delicious apple pomace

Background Synthetic antioxidants and antimicrobials are losing ground to their natural counterparts and therefore, the food industry has motivated to seek other natural alternatives. Apple pomace, a by-product in the processing of apples, is rich in polyphenols, and plant polyphenols have been used as food additives owing to their strong antioxidant and antimicrobial properties. The goal of this study was to screen the individual polyphenols with antioxidant and antimicrobial activities from the extracts (methanol, ethanol, acetone, ethyl acetate, and chloroform) of Golden Delicious pomace. Results First, the polyphenolic compounds (total phenol content, TPC; total flavonoids, TFD; total flavanols, TFL) and antioxidant activities (AAs) with four assays (ferric reducing antioxidant power, FRAP; 1,1-diphenyl-2-picryhydrazyl radical scavenging capacity assay, DRSC; hydroxyl radical averting capacity assay, HORAC; oxygen radical absorbance capacity assay, ORAC) were analyzed. The results showed a significant positive correlation (P