ENZYME PREPARATION FOR UNHAIRING AND SOFTENING LEATHER-FUR RAW Russian patent published in 1999 - IPC

FIELD: biotechnology, leather industry. SUBSTANCE: invention proposes a new bacterial enzyme preparation "PROK" exhibiting total proteolytic activity 300 U/g (by Kunitz) or 300 000 U/g by tyrosine (Anson's method). Preparation hydrolyzes casein at isoelectric point 5.9 and 6.0, optimum pH at 6.8-7.8, range of pH stability at 6.8-7.8. Thermic stability of a preparation decreases at above 45 C. Michaelis constant is 0.9 x 10^-6 M using sodium caseinate as a substrate. Inhibitors: EDTA, phenylmethylsylfanylfluoride, o-phenyl-throline (at concentration above 10^-4 M). Activity of this preparation exceeds that of alkaline protease from Bacillus subtilis but distincts of the latter by capability to make both unhairing and softening leather-fur raw. This excludes the use of pancreatin, decreases a consumption of ecologically harmful polluting agent - sodium sulfide by 2-3-fold, retains wool for the felting industry, shows soft effect of the face hide membrane, increases the yield of ready leather to 5% by square. Enzyme preparation (form ГЗХ) is obtained from cultural fluid filtrate of the strain Streptomyces lavendulae INMI-36-SV by drying in spraying at 120-125 C at inlet and 60-65 C at outlet and by addition of 1% NaCl to dried powder. EFFECT: enhanced effectiveness and properties of an enzyme preparation. 1 tbl