Purification and characterization of a pectin lyase produced by Curvularia inaequalis NRRL 13884 on orange peels waste, solid state culture

Utilization of orange peels as an agroindustrial waste for production of pectin lyase (PL) [E.C.4.2.2.10] by Curvularia inaequalis (Shear) Boedijn NRRL 13884 was investigated using solid state culture (SSC). The highest level of extracellular pectin lyase was detected with this waste as an inducing substrate. The enzyme was purified using Sephadex G-100 and DEAE-Cellulose column chromatography. It was purified about 50 fold. The enzyme optimum activity was at pH 5.0 and 45 degreesC. The enzyme was inhibited by Co++, Mn++ and Zn++ and completely inhibited by Ag++ and Hg++, whereas it was activated in the presence of Ca++ ,Cu++, Mg++, Na+, K+. Also, the enzyme was inhibited by iodoacetate, sodium arsenate, sodium azide, potassium permenganate and potassium ferrocyanide. EDTA and L-cysteine did not affect the enzyme activity. The Km was calculated to be 0.35 mM.