Screeening of chitinases in some crops and partial purification of the exzyme from angled loofah luffa acutangula roxb

Abstract

The extracts from leaves of 7 local plants: star gooseberry, ivygourd, papaya, jackfruit, tamarind, roseapple and Aztec kuamachill, Phaseolus mungo egminosae seeds grown in the presence of colloidal chitin and pericarp of angfah fruit (Luffa acutangula Roxb.) were tested for chitinase activity. Only the extracts from leaves of papaya, seedling of Phaseolus mungo Leguminosae and pericarp of angled loofah fruit gave clearr zones on colloidal chitin-agar plate which is one of the methods for detection chitinase. Chitinase from the crude nextract from pericarp of angled loofah fruit was partially purified up to 18.9 folds by 30-70 % ammonium sulfate precipitation and DEAE-cellulose column chromatography. The fractio from DEAE-cellulose contained 2 chitibases, one contained 2 subunits with molecula weight of 25,000 and 29,000 while the other contain only one 29,000 subunit. The former chitinase showed 2 proteins bands on isoelectric focusing gel with ;I’s of 5.4 and 5.5 while the latter showed one band at pI 5.4. The optimum pH and temperature for the enzyme activity were 3.5 and 3.7 ……,respedtively. The substrate specificity of the enzyme was purified chitin, colloidal chitin and glycol chitosan, respectively.