Bacillus sp. 유래 β-Mannanase의 정제 및 Picea abies Galactosyl Glucomannan 가수분해 올리고당의 중합도별 Bifidobacterium spp.에 대한 생육활성

Abstract

β-Mannanase from Bacillus sp. was purified by DEAE sephadex column chromatography. The specific activity of the purified enzyme was 21.57 units/mg protein, representing an 95.33-fold purification of the original crude extract. The final enzyme preparation obtained showed a single band on the SDS-PAGE and its molecular weight was estimated to be 38.9 kDa. Galactosyl glucomannan from Picea abies was hydrolyzed using the purified β-mannanase, and then the hydrolysates were separated by activated carbon column chromatography. The main hydrolysates were composed of galactosyl glucomannooligosaccharides with a degree of polymerization (DP) of 8 and 10. To investigate the effects of Picea abies galactosyl glucomannanooligosaccharides on the growth of the following: Bifidobacterium longum, B. bifidum, B. animalis, B. breve, B. infantis, B. adolescentis, and B. auglutum, each Bifidobacterium spp. was cultivated into the modified-MRS medium containing galactosyl glucomannooligosaccharides with DP 8 or 10 as a carbon source. The growth of B. animalis increased 19.5-fold and 18.7-fold by the treatment of galactosyl glucomannooligosaccharides with DP 8 and 10, respectively, compared to that of the standard MRS medium. B. bifidum grew 15.3 and 14.3-fold and B. longum grew 15.2 and 13.9-fold by the treatment of galactosyl glucomannooligosaccharides with DP 8 and 10, respectively. Especially, galactosyl glucomannooligosaccharides with DP 8 was more effective than that with DP 10 on the growth of B. animalis, B. bifidum and B. longum.