Pulp antioxidant activities, mineral contents and juice nutritional properties of Algerian Clementine Cultivars and Mandarin
Six cultivars of Clementine fruits including ‘Cadoux’, ‘Monreal‘, ‘St Martin’, ‘Merme’, ’Cheylard’, ’Rocamora’ and one mandarin fruit cultivar were chemically analysed for their juice characteristics (water content, pH, acidity, total soluble solids and ascorbic acid). Ascorbic acid content varied from 35.98 to 69.41 mg/100 ml, Mandarin variety showed the highest value, whereas Clementine St Martin cultivar was the lowest. Lyophilized citrus pulps were analysed for mineral contents and bioactive compounds. Mineral analysis showed that all the fruit pulps were good sources of K, Fe, and Na. Statistical differences among the citrus pulps were established for the contents of phenols, flavonoids and carotenoids, the quantification of bioactive compounds revealed distinct contents amongst the analysed materials. Phenolic and flavonoid contents presented a value between 3108.78 and 4046.20 mg gallic acid/100 g dw and between 946.42 and 1281.98 mg Catechin/100 g dw respectively and in both cases the highest amount was found in Merme cv. and the lowest in St Martin cv. whereas for carotenoid contents, the amount varied from 38.31 to 75.14 mg β-carotene/100g dw and Mandarin was the richest fruit. All citrus fruit pulps exhibited 1,1-di-phenyl-2-picryl-hydrazil (DDPH) scavenging capacity, and reducing power in a concentration-dependent manner, the Merme cv. being the most active one and the St Martin cv. was the weakest. Our results indicate that the Merme cv. was outranking with regard to the contents of phenolic and flavonoid, DPPH and reducing power activity while St Martin exhibited the lowest amounts and the weakest antioxidant activity.
Key words: Clementine fruit, Mandarin, antioxidant activity, bioactive compounds, ascorbic acid, minerals.