The present study evaluated the antioxidant and antimicrobial activities of raw and processed fruit extracts from Solanum torvum, S. xanthocarpum and S. violaceum and assessed the relationship with their total phenolic content. Total phenolic and tannin contents of raw and processed fruit sample extracts ranged from 5.0-7.6 g/100g and 4.5-7.0 g/100g, respectively. As compared to raw samples, processed samples had significant decrease in total phenolic and tannin content, FRAP, linoleic acid emulsion system, antihaemolytic and superoxide anion radical scavenging activity. However, processing the samples caused significant (p<0.05) increases in DPPH•, ABTS •+, •OH radical scavenging capacities, metal chelating ability and phosphomolybdenum assay. After processing, the total antioxidant activity increased or remained unchanged depending on the type of samples. All the fruit samples showed optimal antimicrobial activity against Gram negative bacteria. Interestingly, the extracts from raw and processed S. torvum showed no inhibitory effect on the growth of E. coli.

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