Effect of Mung bean, Pea and Wheat Proteinaceous Seed Extracts on Amylase Activity of the Pieris brassicae Linnaeus (Lepidoptera: Pieridae)

The Cabbage butterfly, Pieris brassicae (Lepidoptera: Pieridae), is a cosmopolitan and a destructive cruciferous pest that has been widely distributed. The aim of the current study was to investigate the effect of proteinaceous extracts of mung bean, pea and two wheat cultivars against the Pieris brassicae midgut α-amylase. Results showed that effects of obtained extracts on amylolytic activity of Pieris brassicae was as a dose dependent manner namely with increasing dose, the amylase activity decreased. Also, the results showed highest dose (1/64, 2, 1 and 1 mg.ml-1) of mung bean, cowpea, Alborz, Kavir caused 16, 4, 51, and 55% inhibition of the insect amylase, respectively. Effect of pH on amylase showed that the greatest inhibition of amylase was observed at pH 8 which is the optimum pH for the activity of the enzyme in in-vitro condition. The results revealed that pH had significant effect on inhibition of wheat seed cultivars on this insect α-amylase. It is concluded that extraction obtained from seeds of wheat cultivars affected more α-amylase of the pieris brassica than pea and mung bean seeds. Thus, proteins present in the wheat cultivars have a good potential to be studied further in order to purify them, indentify their structures and investigate their specificity for α-amylase of different animals.