Hesperidin a major flavonoid with high antioxidant potential and nutraceutical source in dropped fruits of sweet orange (C. sinensis (L.) osbeck)

Food supplements manufacture at present are synthetic and leads to side effects when taken in vivo. Physiological drop fruits are usually discarded which can prove as a natural source of flavonoids and antioxidants with no side effects. Information is scarce regarding beneficial effects of dropped citrus fruits. The fruits dropped naturally were collected and evaluated for their potential use as nutraceutical materials. The flavonoids including hesperidin, narirutin/isonaringin, diosmin and didymin/neopocirin and antioxidants were analysed. The flavonoid content ranged from hesperidin (7.597±0.20 to 20.543±0.39%), narirutin/isonaringin (0.173±0.02 to 1.153±0.18%), diosmin (0.270±0.02 to 2.520±0.07%) and didymin/ neoponcirin (0.094±0.03 to 1.010±0.08%) respectively and varied among different sizes of dropped fruits. Among all flavanone glycosides, hesperidin was the most abundant. Antioxidants assessed with ABTS, DPPH, FRAP and TPC ranged from 8.583±0.02 to 12.364±0.29 mM L−1 Trolox, 8.464±0.08 to 15.701±0.12 mM L−1 Trolox, 4.080±0.07 to 6.386±0.10 mM L−1 Trolox and 40.736±2.12 to 56.161±1.05 mg GAE L−1. The highest content of antioxidants was found in immature fruits during initial developmental stages. Positive correlation was found between flavonoids and antioxidants. The study suggest that physiologically dropped sweet orange fruits could serve as a good source for extraction of bioactive compounds beneficial for pharmaceutical as well as nutraceutical industries.