Betacyanin (betanin), total phenolics, vitamin C and antioxidant capacity (by Trolox-equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity (ORAC) assays) were investigated in two differently colored cactus pear (Opuntia ficus-indica (L.) Mill.) genotypes, one with purple fruit and the other with orange fruit, from the Salento area, in Apulia (South Italy). In order to quantitate betanin in cactus pear fruit extracts (which is difficult by HPLC because of the presence of two isomers, betanin and isobetanin, and the lack of commercial standard with high purity), betanin was purified from Amaranthus retroflexus inflorescence, characterized by the presence of a single isomer. The purple cactus pear variety showed very high betanin content, with higher levels of phenolics, vitamin C, and antioxidant capacity (TEAC) than the orange variety. These findings confirm the potential for exploiting the autochthonous biodiversity of cactus pear fruits. In particular, the purple variety could be an interesting source of colored bioactive compounds which not only have coloring potential, but are also an excellent source of dietary antioxidant components which may have beneficial effects on consumers’ health.

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Our findings suggest that mahaleb fruit (currently not consumed fresh or used in other ways) could serve as a source of bioactive compounds and therefore find interest from the functional food and nutraceutical industries, as a natural food colorant and antioxidant ingredient in the formulation of functional foods. © 2015 Society of Chemical Industry.

Olive fruits (OF) and virgin olive oil (VOO) have nutritional and sensory characteristics that make it unique and a basic component of the Mediterranean diet.1 The chemical composition of phenolic of OF and VOO is mainly affected by the variety, location, and environmental conditions.2 Phenolic compounds of OF and VOO affect olive and oil shelf lifes since they retard oxidation and the sensorial properties: color, astringency, bitterness, and flavour.2,3 and possess protective effects on human health, including cancer and cardiovascular diseases. In the present study, the identification and quantitation of the most representative phenolic compounds present in OF and VOO of two Algerian (chamlal and sigoise) and some Italian cultivars (leccino cat, ogliarola bradano, maiatica pandolfo, frantoiana pandolfo, leccino pandolfo, frantoiana cat, coratina) using HPLC-DAD based method is reported. HPLC-DAD HRMS was also used to confirm results obtained. Quantitative or semi-quantitative information on OF and VOO phenols is of great interest to find the compounds responsible of the olive oil benefits and to distinguish VOOs with different geographical origin.2,3 Analyzed olive extracts and oils demonstrated significative differences (p < 0.05) in secondary metabolite identified, expecially concerning phenolic acids. The antioxidant activity was also measured using: 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power and β-carotene bleaching assays, 4,5 and relative antioxidant capacity index.5 According to all tests, the highest hydroxytyrosol amount and antioxidant capacity were observed for the Italian cultivars coratina and ogliarola, and the Algerian cultivar chamlal