3.2. Total Tannins Content
Tannins, another major group of polyphenols in our diets, are the important plant secondary metabolites [21].The amounts of total tannins in the blueberry leaf extracts are shown in Table 1. Thehighest value of tannins was obtained in both 50% ethanol and 100% methanol extracts. It was slightly reduced in 95% ethanol extracts while the smallest value was found in 70% acetone extracts. Iniyavan et al. [21] stated that the total phenolic and tannin contents were higher (7-fold and 46-fold, respectively) in pure acetone extracts of P. nilgiriensisleaves than in pure methanolextracts.