A novel isolation and purification of antifungal chitinase from cowpea (Vigna unguiculata) and its possible biotechnological applications

A novel chitinase enzyme with molecular weight of approximately 50KDa was isolated from cowpea seeds. It was purified using ammonium sulphate and chitin affinity binding techniques. The enzyme was purified to 1.84-fold protein with specific activity of 2.017U/mg using ammonium sulphate precipitation and the purification increased to 7.76-fold protein and specific activity of 8.479 U/mg after chitin affinity binding technique. The enzyme showed strong antifungal activity against Fusarium oxysporum , F. solani and Alternaria alternata and moderate activity against Penicillium frequantes . The new enzyme may represent an additional element for constitutive defense in cowpea plant. The enzyme also showed moderate antifungal activity against Saccharomyces cerivisiae and very strong activity against Candida Albicans . This finding suggests its possible role as antifungal agent against some phytopathogenic fungi in the field and also its possible usage in food industry and food preservation. Besides, its anticandidal activity suggests its possible pharmaceutical applications.