Determination and correlation of carotenoid pigments and their antioxidant activities in marigold (Tagetes sp.) flowers

Abstract

Marigold (Tagetes sp.) flowers are considered as an important source of carotenoid pigments namely xanthophylls (lutein, zeaxanthin) and yellow carotenoids (β-carotenes). In present study, different marigold genotypes were evaluated for colour values for abaxial and adaxial surface of petals, total carotenoids, phenolic and flavonoid content and their antioxidant activities. The colour parameters such as L, a, and b for abaxial and adaxial petal surfaces exhibited the significant differences for colour values among genotypes. Among the various genotypes studied, selection Af/w-6 had highest total carotenoids (525.68 mg/100g) on fresh weight basis followed Pusa Narangi Gainda (339.92 mg/100g) and Pusa Arpita (160 mg/100g). Total phenolic content on fresh weight basis of petals ranged from 81.93 to 136.17 mg GAE/g whereas, flavonoid content ranged from 37.11 to 65.13 mg RE/g. Highest antioxidant activity measured by DPPH radical scavenging activity and Ferrous Reducing Antioxidant Power (FRAP) was found in selections Af/w-6 (891.16 μmol FeSO4/g and 82.17%) followed by Af/w-4 (809.29 μmol FeSO4/g; 81.55%). A high correlation between carotenoids, total phenolic and flavonoid content, antioxidant activities was observed.