PHYSICOCHEMICAL PROPERTIES OF TERMITE CELLULASES (INSECTA : ISOPTERA) BASED ON THE TROPHIC GROUP (DALOA, COTE D IVOIRE)

The distribution of termites according to trophic groups in agrosystems, causes damage leading to a decrease in yield of crops. This results in growing food insecurity for the population. Many control methods used against these pests have shown their inadequacy. The understanding of the functioning of digestive enzymes is therefore necessary. The present study aims to compare the physico-chemical properties of termite cellulases as a function of trophic groups. Four enzymatic extracts of humivorous (Cubitermes fungifaber) and xylophagous termites (Amitermes guineensis, Nasutitermes latifrons, Microcerotermes fuscotibialis) were used. The results show an optimum difference in temperature of hydrolysis within xylophage cellulases, although they are all mesophilic, acidic with optimum hydrolysis pH of 5.6 and better expressed in 20 mM sodium acetate buffer. In addition, the cellulase activities of C. fungifaber and A. guineensis are maximum at 60 ?C while those of N. latifrons and M. fuscotibialis are at 55 ?C respectively. As for relative activities, they are different among the three xylophagous species. N. latifrons has the highest relative cellulase activity. This result reflects the voracious behavior of this one on cocoa trees.