Abstract
Antioxidative and cholesterol-reducing activity of Bacillus polyfermenticus SCD were measured to characterize its probiotic properties. DPPH (1,1-diphenyl-2-picyryl hydrazyl) radical scavenging activity of the culture supernatant of B. polyfermenticus SCD was estimated to be 48%. The culture supernatant on the peroxidation of linoleic acid were investigated and the value was shown to be about 45%. The inhibition of TBA (2-thiobarbituric acid) formation of the culture supernatant was revealed 60% when stimulator was presented. The SOD-like activity of the culture supernatant was about 15%, which is similar to BHT (butylated hydroxytoluene) and ${\alpha}$-tocopherol. After cultured in TSB broth added soluble cholesterol either 0.1% or 0.3% of oxgall in 37$^{\circ}C$ for 24 h aerobically, cholesterol-reducing activities were revealed about 67% or 64%, respectively. To test whether the products are cholesterol-related or not, residual activity was determined. The cholesterol activity was rarely changed. In addition, when the cell extracts recovered after cultivation, was tested in absence of cholesterol, cholesterol activity was not detected. However, cholesterol activity was detected in the presence of cholesterol. Thus, it was assumed that B. polyfermenticus SCD could reduce cholesterol by conjugating with it, rather than by digesting the cholesterol using cholesterol-hydrolyzing enzymes.
프로바이오틱 생균인 B. polyfermenticus SCD의 유용성을 확인하기 위해 항산화 및 콜레스테롤 저하 효과를 검증하였다. DPPH법에 의한 항산화 활성은 48% 정도였으며, TCA법에 의한 활성은 45%로 측정되었다. 그리고 TBARS 법에 의해 측정된 활성은 stimulator가 존재할 때 60%에 달하였으며, SOD 유사활성은 15% 정도였다. 이러한 활성은 기존의 항산화제인 BHT나 $\alpha$-tocopherol의 1% 용액과 비교할 때, 비슷하거나 약간 낮은 수치를 보여 준다. 향후 항산화 물질이 정제되어 이 물질의 1% 용액과 1% 농도의 기존 항산화제의 활성을 비교하여야 한다. 그러나 이 같은 뚜렷한 B. polyfermenticus SCD의 항산화력을 바탕으로 천연 항산화제 개발이 가능하다고 판단된다. 한편 B. polyfermenticus SCD의 콜레스테롤 저하 효과는 0.3% oxgall이 존재할 때, 64% 정도였다. 이 수치는 oxgall이 존재하지 않을 때 수치(67%)와 비교할 때, 큰 변화가 없었다. 그리고 콜레스테롤 저하 기작은 세포내 흡착에 의한 것으로 판단되었다.
