Antioxidant Capacity of Phenolic from Seed Extracts of Lagenaria siceraria (Short-Hybrid Bottle Gourd)

Aims: To evaluate the antioxidant components and antioxidant activities of seed extracts of Lagenaria siceraria (Short-Hybrid Bottle Gourd).

Study Design: In vitro assessment of antioxidant assays; quantitative determination of phenolic phytochemicals in seed extracts of short-hybrid bottle gourd.

Place and Duration of Study: Department of Chemistry, Faculty of Science and Department of Pharmaceutical and Medicinal Chemistry, Faculty of Pharmacy, University of Uyo, Nigeria (September 2013 –July 2014).

Methodology: Standard methods were used to evaluate the concentration of total phenols, total flavonoids, β-carotene, tannins, vitamin C and vitamin E in the seed extracted with different polar solvents (diethyl ether, chloroform, ethyl acetate, n- butanol, methanol and water). 2, 2-Diphenyl-1-picrylhydrazyl (DPPH)-radical scavenging activities, iron chelating activity and ferric reducing antioxidant power (FRAP) were also determined using standard methods.

Results: The total phenols content ranged from 30.1-63.1 µgGAE/g, total flavonoids (30.1-49.2 µgQE/g), carotenoids (0.071-2.599 mg/100 g), tannins (7.0-25 mg/100 g), vitamin C (2.5-12.0 mg/100 g) and vitamin E (5.5-25 mg/100 g). In vitro antioxidant activity of the extracts (100 µg/ml) for DPPH scavenging assay was between 57.2-63.4% and IC50 (50.0- 85.0 µg/ml); metal chelating (49.0–59.0%) and IC50 (32.0-105.0 µg/ml); and ferric reducing capacity (0.466-0.724) and IC50 (24.0-115 µg/ml).

Conclusion: The seed extracts of L. siceraria contains substantial amount of polyphenolic compounds and exhibits significant antioxidant activity. The results of this study substantiates the role of these seeds as natural sources of antioxidants which could be further exploited for their potential biological activity in related cultivars which hitherto were scarcely used as soup thickener and for dough, cakes and edible oils.