The digestive tract of insects contains proteolytic enzymes, which participate in the digestive process. A detailed knowledge on the activity of these enzymes will enable the selection and assessment of different inhibitors that may be used in the design and development of strategies allowing the control of Hypothenemus hampei. In order to determine, the pH and optimum temperature of endogenous proteolytic activity, the isoenzymatic profile and the type of proteinase present in the digestive tract of this insect, 0.05g of freeze dried extract of adult borer were prepared with 500µl of different extraction solutions: water, 1% NaCl and buffer solutions 0.05M pH (3.0 - 6.0). The determination of the optimum pH was carried out by using buffing solutions of pH (1.5 – 4.5) 0.2M. The optimum activity temperature was assayed between 30° and 70°C. The type of digestive proteinase was determined by using Pepstatin A synthetic inhibitor in concentrations of 1µM, 5µM and 10µM. In all cases; the enzymatic activity was determined spectrophotometricaly at 280nm. The isoenzymatic profile was done in native gels of 16%. The results showed that the best extraction solution is buffer citrate pH 3.0, the optimum temperature is between 30° and 40°C. The proteinase found in the digestive tract was identified as an aspartic type Catepsin. In the zymogram, at least 3 well-defined bands of proteolytic activity were found two of which are present borer adults and in the intestines.

Index terms: Coffee berry borer, Hypothenemus hampei, enzymes, proteases

---