Role of phenylalanine/tyrosine ammonia lyase and anthocyanidin synthase enzymes for anthocyanin biosynthesis in developing Solanum melongena L. genotypes

Solanum melongena is a widely consumed vegetable crop comprising health-benefiting phenolic compounds. It has a complex network of biosynthetic enzymes involved in synthesizing nutraceuticals, including anthocyanins. The present study was conducted to investigate the activities of key enzymes involved in biosynthesis and accumulation of anthocyanins in developing genotypes, such as phenylalanine ammonia lyase (PAL), tyrosine ammonia lyase (TAL), and anthocyanidin synthase (ANS). As inadequate information is available in this context, fruit and leaf tissues were analyzed for enzyme activities and anthocyanin accumulation. The study included characterization of extracted anthocyanin followed by expression studies for gateway enzyme (ANS) involved in anthocyanin biosynthesis. Delphinidin was a major anthocyanidin present in fruit tissues (1.46-110.49 mg/100 g) of S. melongena. Anthocyanin accumulation is backed up by the correlation between biochemical analysis and expression studies. The study has shown variation for PAL, TAL and ANS enzymes in different tissues at developmental stages. Enzyme activities had a strong positive correlation with anthocyanin biosynthesis.