| 摘要 |
PURPOSE:To obtain the subject new strains high in heat resistance, wide in active pH range, low in the inhibition by reaction products, capable of producing a beta-galactosidase enabling lactose-contg. foods to be treated at such elevated temperatures as to be hard to be septic for sundry germs. CONSTITUTION:The new strains can be obtained by screening, according to conventional method from the soil of the various parts of the whole of Japan, microbes capable of producing a beta-galactosidase. The new strains, which belong to Thermus, consist of Thermus sp. ZK-001 (FERM P-9184), ZK-002 (FERM P-9185) and ZK-003 (FERM P-9186), each being bacillus in shape, (0.4-0.6)X(2-7)mum in size and inviable under anaerobic conditions. The p- galactosidase is a new one having optimum activity temperatures of 75-85 deg.C and optimum pH levels of 4.5-6.5, not declining in activity by 50mmol of galactose or glucose, and capable of treating lactose-contg. foods such as cow milk, skim milk, cheese whey and lactose liquor at such elevated temperatures as to be hard to be septic for sundry germs. |
