Standardization of storage conditions of marigold (Tagetes sp.) petal extract for retention of carotenoid pigments and their antioxidant activities

Abstract

Present investigation was carried out to find the effect of different storage temperatures and durations on retentionof total carotenoids, antioxidant activities and other secondary metabolites of marigold petal extract in varieties Pusa Arpita, Pusa Basanti Gainda, and Pusa Narangi Gainda. It was observed that the highest retention of carotenoids, lutein, b-carotene, phenolic and flavonoid contents and antioxidant activities were recorded at storage temperature of -20°C followed by 4°C and lowest retention was observed at ambient storage temperature. It was revealed from the studies that the carotenoids, total phenolics, total flavonoids and antioxidant activities were decreased during storage. Among varieties, Pusa Narangi Gainda retained more carotenoids (1 925.26 mg/100g DW) and antioxidant activities (FRAP- 647.83 μ mol FeSO4/g; DPPH-59.51%), whereas, Pusa Arpita retained more lutein (228.87 μg/g) and β- carotene content (15.49μg/g) stored at -20°C. The storage of vacuum dried petals at -20°C temperatures was found suitable for higher retention of bioactive compounds.