D. Sarkar, A.M. Khan, S. Maitra, I. Sarkar and P.K. Paul
Abstract
Anthocyanin and carotenoids are the two major groups of plant pigments having beneficial effects on human body. Anthocyanin, a water-soluble coloured flavonoid that imparts red, blue and purple colour in fruit, vegetables and flowers possesses anti-carcinogenic and anti-inflammatory properties, preventive in cardiovascular diseases, obesity and diabetes, and improves visual and brain functions. Carotenoids, C40 isoprenoid compounds, impart yellow to orange red colours to flowers are antioxidants, anti carcinogenic, protect cornea against UV light, and reduces cholesterol levels. Flowers are prominent sources of these two bio-compounds. The present study aimed at extraction of anthocyanin and carotenoid from flowers of nine common landscape plants (Erythrina indica, Delonix regia, Spathodia campanulata, Casis fistula, Peltophorum pterocarpum, Cassia alata, Lagerstroemia sp., Clitoria sp. and Eicchornia crassipes) blooming in red, yellow and blue, through four aqueous extraction methods with varying temperature and microwave assistance. The results indicated that the anthocyanin and carotenoid content varied significantly among the flower species, methods of extraction and their interaction. Maximum anthocyanin content was obtained from blue-coloured flowers of Clitoria sp. (64.44 mg l-1) in microwave assisted extraction and maximum carotenoid content from red-coloured flowers of Delonix regia (99.60 õg g-1) in cold water maceration.