Compositional variation in β-carotene content, carbohydrate and antioxidant enzymes in selected banana cultivars

Banana is one of the most important tropical fruits, and India ranks first in its world production. Banana cultivars rich in provitamin A carotenoids may offer a potential food source for alleviating vitamin A deficiency, particularly in developing countries. With a view to exploit banana peels as a source of valuable components, in the present study, proximate composition, carotenoids, beta-carotene and some anti-oxidative enzymes as well as carbohydrate content of selected Indian banana varieties were determined. Karpooravalli cultivar of banana showed the maximum accumulation of carotenoid content in the non-edible (68 mu g g(-1) d.w.) portion of banana, while being the second highest in beta-carotene content (143.12 mu g per 100 g). However, Red Banana ranked highest in total carotenoid contents for pulp (4 mu g g(-1) d.w.) and beta-carotene was estimated to be the highest in the case of peels (241.91 mu g per 100 g) and in pulp (117.2 mu g per 100 g). Karpooravalli cultivar of banana is also rich in carbohydrate content in terms of total starch (1786.0 mu g g(-1) d.w. in peels and 544.85 mu g g(-1) d.w. in pulp) and sugars (53.53 mu g g(-1) d.w. in peels and 39.05 mu g g(-1) d.w. in pulp). The catalase enzyme activity in these peels ranged from 5.66 to 35.57 nmol min(-1) mg(-1) proteins and was found at a higher level in cultivar Poovan, while the ascorbate peroxidase showed the range of 2.25 to 6.22 mu mol min(-1) mg(-1) proteins. The peels of cultivars Red Banana and Karpooravalli are rich source of bioactive compounds, such as carotenoids (beta-carotene), anti-oxidative enzymes and carbohydrate contents.