Abstract
Crude preparations of larval midgut proteases from Heliothis armigera (Hübner) and H. assulta (Guenee) were made with double salt (ammonium sulfate) precipitation at 35% and then 75% saturation. Three proteases were resolved from each of these preparations with DEAE-cellulose chromatography. The elution profiles were similar for both preparations. These resolved proteases also had similar pH optima at pH 11, temperature optima between 55 and 60°C, and a wide pH stability range between pH 4 and pH 10. These proteases were illustrated to be serine proteases based on their inhibition properties toward specific protease inhibitors. Tannic acid had selective inhibitory effects on these proteases. The specificity of inhibition of tannic acid toward these proteases was found to correlate with previous estimates of its effect on digestibility of the larvae.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
