Naringinase which was extracted from the fermented broth of Cryptococcus albidus was purified about 42-folds with yield 0.7% by sulfate fractionation and chromatography on Toyopearl HW-60, Fractogel DEAE-650-s, and Sepharose 6B columns. Molecular weight of protein determined by gel filtration and SDS-PAGE was 50 kDa. Naringinase of C. albidus includes high content of the dicarbonic and hydrophobic amino acids. Enzyme contains also carbohydrate component, represented by mannose, galactose, rhamnose, ribose, arabinose, xylose, and glucose. The enzyme was optimally active at pH 5.0 and 60 °C. Naringinase was found to exhibit specificity towards p-nitrophenyl-α-L-rhamnose, p-nitrophenyl-β-D-glucose, naringin, and neohesperidin. Its K towards naringin was 0.77 mM and the V was 36 U/mg. Naringinase was inhibited by high concentrations of reaction product-L-rhamnose. Enzyme revealed stability to 20% ethanol and 500 mM glucose in the reaction mixture that makes it possible to forecast its practical use in the food industry in the production of juices and wines.

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Peptidase of Bacillus thuringiensis var. israelensis IМV В-7465 was isolated from culture supernatant using consecutive fractionations by an ammonium sulphate (60% saturation), ion-exchange chromatography and gel-filtration on the TSK-gels Toyoperl HW-55 and DEAE 650(M). Specific elastase (442 U∙mg of protein-1) and collagenase (212.7 U∙mg of protein-1) activities of the purified enzyme preparation were 8.0- and 6.1-fold, respectively higher than ones of the culture supernatant. Peptidase yields were 33.5% for elastase activity and 30.1% for collagenase activity. It was established that the enzyme is serine metal-dependent alkaline peptidase with Mr about 37 kDa. Maximal hydrolysis of elastin and collagen occurs at the optimum pH 8.0 and t° – 40 and 50 °С, respectively. The purified preparation has high stability at pH in the range of 7.0 to 10.0 and 40-50 °С.

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