• Applied Biological Chemistry
• /
• 제46권3호
• /
• pp.165-170
• /
• 2003

발효식품 시료로부터 분리된 세균을 $DPPH({\alpha},{\alpha}'-diphenyl-{\beta}-picrylhydrazyl)$ 전자공여능으로 항산화 활성을 측정하여 가장 활성이 강한 균주를 선별하여 형태학적, 생화학적, 생리학적 특성 및 165 rRNA 염기서열을 조사한결과 Bacillus sp.으로 판명되어 FF-7로 명명하였다. DPPH 전자공여능법에 의한 Bacillus sp. FF-7이 생산하는 항산화물질의 최적 생산 배지조건은 탄소원 2% galactose와 질소원 1% tryptone 첨가였다. Bacillus sp. FF-7에 의해 생성된 항산화 물질의 활성을 DPPH 전자공여능, 흰쥐 각 조직 microsomal 실험계 및 linoleic acid 과 산화지질 실험계에서 malondialdehyde를 thiobarbituric acid(TBA)방법으로 측정하였다. 흰쥐 각 조직 microsomal 실험계에서 지질과산화에 대한 항산화 효과는 뇌(97.50%) >심장(79.95%) >신장(77.84%) >비장(77.47%) >고환(69.96%) >간장(62.45%) 순이였다. Linoleic acid의 과산화지질를 TBA법으로 측정한 결과 반응 4일째까지 억제 효과가 강하게 나타났으며, 동시에 대조구로 사용한 0.05% BHT 첨가구에서도 실험종료시까지 항산화 활성이 강하게 나타났다.

• Journal of Microbiology and Biotechnology
• /
• 제23권9호
• /
• pp.1221-1228
• /
• 2013

Two lipase genes (bpl1 and bpl3) from Antarctic Bacillus pumilus strains were expressed in Bacillus subtilis. Both recombinant lipases BPL1 and BPL2 were secreted to the culture medium and their activities reached 3.5 U/ml and 5.0 U/ml, respectively. Their molecular masses apparent using SDS-PAGE were 23 kDa for BPL1 and 19 kDa for BPL3. Both lipases were purified to homogeneity using ammonium sulfate precipitation and HiTrap SP FF column and Superose 12 column chromatographies. The final specific activities were estimated to be 328 U/mg for BPL1 and 310 U/mg for BPL3. Both lipases displayed an optimum temperature of $35^{\circ}C$, similar to other mesophilic enzymes. However, they maintained as much as 70% and 80% of the maximum activities at $10^{\circ}C$. Accordingly, their calculated activation energy at a temperature range of $10-35^{\circ}C$ was 5.32 kcal/mol for BPL1 and 4.26 kcal/mol for BPL3, typical of cold-adapted enzymes. The optimum pH of BPL1 and BPL3 was 8.5 and 8.0, respectively, and they were quite stable at pH 7.0-11.0, showing their strong alkaline tolerance. Both lipases had a preference toward medium chain length ($C_6-C_{10}$) fatty acid substrates. These results indicate the potential for the two Antarctic B. pumilus lipases as catalysts in bioorganic synthesis, food, and detergent industries.

• 한국조리학회지
• /
• 제12권2호
• /
• pp.168-183
• /
• 2006

The purpose of this study was to investigate quality characteristics of roll bread with the addition of Chungkukjang powder(0, 5, 10, 15, 20%). The antioxidative activity of antioxidative substances produced from several bacterial strains isolated from fermented foods were tested by DPPH $(\alpha,\alpha’-diphenyl-\beta-picrylhydrazyl)$ free radical scavenging activity. The most optimal medium condition for the production of antioxidative substance from Bacillus sp. FF-7 was 2% galactose as carbon source and 1% tryptone as nitrogen source. In color values, with increasing Chungkukjang powder content, the "lightness" (p<0.05) decreased in the crumb bread, while the redness(p<0.05) and yellowness(p<0.05) increased. The volume and specific volume of roll bread with 5.0% Chungkukjang powder were the highest(p<0.05). In the rheology measurements for the roll bread, the hardness (p<0.05) decreased with the addition of 5.0% Chungkukjang powder, but then increased with further additions of Chungkukjang up to 10.0%. Highest sensory scores for color, flavor, taste(p<0.05), texture(p<0.05) and overall acceptance(p<0.05) were obtained from roll bread with 5.0% Chungkukjang powder and control. From the results of this study, it was assumed that the development of food products using Chungkukjang is prospective in response to health-oriented consumers.