Amino acid content and transaminases activities in anabaena oryzae and nostoc muscorum as affected by some pesticides

ABSTRACT

Dimethoate and Karathane induced statistically highly -significant decreases in GOT activities of Nostoc and Anabaena. Dursban was less effective, whereas trifluralin encouraged the enzyme activity in Anabaena, but hardly affected it in Nostoc. GPT, behaved differently in both organisms, as a result of pesticides application. Since it was stimulated in dimethoate treated cultures of either cyanobacterium. Dursban, Karathane, and trifluralin, although favored the enzyme activity in Anabaena, yet they inhibited or even totally arrested its potentiality in Nostoc. The moderate doses of dimethoate, Karathane and trifluralin attenuated synthesis of all individual amino acids in both organisms, though valine was hardly affected. Dursban on the other hand, encouraged the biosynthesis of all individual amino acids in Nostoc and Anabaena; an effect that led subsequently to significant elevation in total amino acid content of the two cyanobacterial biomasses. The applied pesticides, at all levels, accelerated heterocyst development in Anabaena, but were of no detectable effects on its differentiation in Nostoc