Youssef,, L. (2004). STUDIES CONCERNING SOME PROPERTIES OF THE ENZYME PROTEASE IN THE COTTON LEAf WORM, SPODOPTERA UTTORAUS-(BOISD.). Journal of Plant Protection and Pathology, 29(5), 2897-2906. doi: 10.21608/jppp.2004.239722
l. A. Youssef,. "STUDIES CONCERNING SOME PROPERTIES OF THE ENZYME PROTEASE IN THE COTTON LEAf WORM, SPODOPTERA UTTORAUS-(BOISD.)". Journal of Plant Protection and Pathology, 29, 5, 2004, 2897-2906. doi: 10.21608/jppp.2004.239722
Youssef,, L. (2004). 'STUDIES CONCERNING SOME PROPERTIES OF THE ENZYME PROTEASE IN THE COTTON LEAf WORM, SPODOPTERA UTTORAUS-(BOISD.)', Journal of Plant Protection and Pathology, 29(5), pp. 2897-2906. doi: 10.21608/jppp.2004.239722
Youssef,, L. STUDIES CONCERNING SOME PROPERTIES OF THE ENZYME PROTEASE IN THE COTTON LEAf WORM, SPODOPTERA UTTORAUS-(BOISD.). Journal of Plant Protection and Pathology, 2004; 29(5): 2897-2906. doi: 10.21608/jppp.2004.239722
STUDIES CONCERNING SOME PROPERTIES OF THE ENZYME PROTEASE IN THE COTTON LEAf WORM, SPODOPTERA UTTORAUS-(BOISD.)
Plant protection Department, Faculty of Agriculture, Ain Shams University .
Abstract
The proteolytic enzyme from midgut (epithelia and peri trophic membrane) of the fifth instar larvae Spodoptera Iittoralis(Boisd.) is extracted and checked as crude preparation with casein sodium as substrate .Also, the effect of (20%) extracts of bestachia and dumb cane leaves on enzyme activity ,is studied.
The protease activity is affected by different factors;e.g incubation period, enzyme and substrate concentrations, pH number and starvation . The least activity of the enzyme occurs at 40 min incubation period.The protease's found to be alkaline as its optimum pH Is about(10).Starvation shows an abrupt Increase in enzyme activity only for the first two hrs., then followed by a conUnious decrease in its activity.
A significant Inhibition In the activities of protease,a'so OCCUI'$ when larvae are fed on castor bean leaves treated with bestachia and dumb cane extracted in methanol and hexane.
There Is a poSitive correlation between both enzyme an~ substrate concentrations and the enzyme protease activity.