TOTAL LIMONOID CONCENTRATION AND ANTIOXIDANT CAPACITIES OF EXTRACTS FROM SEEDS OF DIFFERENT CITRUS VARIETIES USING DIFFERENT SOLVENTS

Tóm tắt

Citrus seeds contain high amounts of limonoids which prove their role in health promoting properties. In this study, total limonoid aglycones, limonin content and antioxidant capacities of the extracts of three kinds of citrus seeds including Dao lime, Vinh orange and Thanh Tra pomelo were investigated. The limonoids were extracted with ethyl acetate, acetone, methanol and dichloromethane using the conventional extraction method. The total limonoid aglycones was quantified by a colorimetric method using DMAB indicator reagent, while the antioxidant activies were determined by both DPPH and ABTS radical scavenging assays. The results indicated that pomelo seeds contained the highest amount of total limonoid aglycones (44.04 μg/g) when extracting with ethyl acetate, followed by those of orange seeds (27.96 μg/g) and lime seeds (27.66 μg/g). The limonoid contents of the methanol-based extracts from lime, orange and pomelo seeds were higher than other solvent-based extracts (19.06, 12.44 and 13.72 μg/g, respectively). The resultsalso indicated that the extracts of pomelo seeds had higher DPPH and ABTS radical scavenging activities than those of lime and orange seeds, whereas the extracts of the orange and lime seeds exhibited no significant difference in antioxidant capacities. The methanol showed the best extraction yield, whereas the dichloromethane was the least effective solvent among all solvents.