Determination of total phenolic contents and antioxidant activities of fruits from wild and creole Carica papaya genotypes in comparison to commercial papaya cultivars

Antioxidant activity (AA), total polyphenols content (TPC) and polyphenols profile (PP) were investigated during 10 days of postharvest ripening, in peels and pulps from fruits from three Carica papaya genotypes of different origin. Wild-genotype (WG) collected in Yucatan, Mexico (part of its center of origin) showed higher AA and TPC values than the commercial-genotype (CG). Likewise, PP analysis resulted in the identification and quantification of 4 families: phenolic acids, flavanols, dihydrochalcones and flavonols in both peels and pulps, as well as lignans, that were only found in fruit peels. Interestingly, fruits from WG also had higher contents than CG, in the following specific polyphenols: in peels; 5-O-Caffeoylquinic acid (chlorogenic acid) and kaempferol (both absent in CG), 4-Hydroxybenzoic acid 4-O-glucoside (3.8 times), quercetin 3-O-hexoside (3.5 times), 4-O-Caffeoylquinic acid (2.8 times), 5-O-Galloylquinic acid (2.7 times) and matairesinol (2.6 times). In pulps; 4-O-Caffeoylquinic acid (9.4 times), quercetin-3-O-rutinoside (rutin; 6.8 times), p-Coumaric acid 4-O-glucoside (p-coumaroyl hexoside; 2.5 times),p-Coumaroyl glycolic acid (2.5 times) and phloridzin (1.7 times). The superior capacity of wild native genotypes to accumulate more total polyphenols, to show higher antioxidant activity and to show even higher contents of some specific polyphenols known to have beneficial health effects (against chronic degenerative diseases such as cancer and cardiovascular diseases), might represent a good base for breeding programs aiming to obtain new varieties with superior nutraceutical properties.