Metabolic profiling of phenolics of the extracts from the various parts of blackberry plant (Syzygium cumini L.) and their antioxidant activities

The phenolic metabolites were extracted from the defatted leaves, seeds and pulp of blackberry using 80% ethanol. The phenolic profiles and antioxidant activities of the extracts so obtained were then evaluated. In addition, metabolic pathway determination was performed by metabo Analyst as well as multivariate analysis to find the relationship between antioxidant activities of different parts of the blackberry plant and individual phenolic metabolites and other phenolic compounds. The result showed that immature leaves contained significantly (p ≤ 0.05) higher total phenolic and flavonoid content as well as FRAP. Meanwhile, tannin and anthocyanin were significantly (p ≤ 0.05) higher in the pulp than in other parts of blackberry. The most abundant metabolic phenolic acid in immature leaves was p–coumaric acid (1160 mg/100g), followed by rutin (985.24 mg/100g), epicatechin (817.99 mg/100g), syringic acid (805.68 mg/100g), catechol (316.32 mg/100g), and gallic acid (313.73 mg/100g). Multivariate analysis showed that different parts of the blackberry were correlated with phenolic metabolites. The Pearson correlation between antioxidant activity and certain phenolic metabolites has been found to be both positive and negative. These results suggest that all parts of the blackberry could be used as a potential source of bioactive compounds for potential use in the food and pharmaceutical industries.