Free radical scavenging activity and cytotoxicity assay of Cissus sicyoides berries

Abstract

BACKGROUND: The leaves of Cissus sicyoides has been utilized in traditional medicine. The berries however are underutilized and do not appear to be widely consumed. OBJECTIVE: This study was undertaken to further evaluate the antioxidant properties of C. sicyoides berries. METHODS: The free radical scavenging activity and IC50 value (inhibitory concentration) of Cissus sicyoides berries was determined utilizing the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Aqueous two-phase partitioning was utilized for preliminary purification of phenylalanine ammonia-lyase (PAL). PAL activity was determined using an endpoint spectrophotometric assay. The cytotoxicity of the berries was assessed by use of the Brine shrimp assay. RESULTS: C. sicyoides berries exhibit excellent free radical scavenging activity with an IC50 value of 0.99 mg/mL which is intermediate to that of raspberries and blackberries. The berries are a potential source of PAL with enzyme activity of 0.10±0.01 U/mg protein. CONCLUSION: Preliminary investigations suggest that the fruits are non toxic and may be utilized as a source of antioxidants. It is evident that the plant is a good source of bioactive compounds with significant potential for food, beverage and medical applications.