• 한국약용작물학회지
• /
• 제20권6호
• /
• pp.472-478
• /
• 2012

This study was carried out to investigate solid-state fermentation method using cellulolytic lactic acid bacteria Lactobacillus plantarum TO-2100 in order to increase piperidine alkaloid contents in mulberry leaves. Piperidine alkaloid, one type of which include 1-deoxynojirimycin (1-DNJ), is known to inhibit ${\alpha}$-glycosidase activities. Using this strain, the optimal solid-state fermentation conditions on mulberry leaves powder were found as the following: initial moisture content, temperature and relative humidity were 20%, $30{\sim}35^{\circ}C$ and 60 ~ 70%, respectively, and the fermentation time was 72 hrs. The piperidine alkaloid contents in the fermented mulberry leaves were 2.86% on dry powder, which is 7-fold increase from that of non-fermented mulberry leaves. The 1-deoxynojirimycin contents after applying preparative thin layer chromatography were 2.02% on dry powder, which is 8 times higher than that of non-fermented mulberry leaves. ${\alpha}$-Glycosidase activities was inhibited by 65.7 ~ 84.7% with 3 ~ 5% treatments of hot-water extracts of the fermented mulberry leaves, compared to 16.2 ~ 40.2% with 3 ~ 5% treatments of hot-water extracts of non-fermented mulberry leaves. Therefore, the results suggest that solid-state fermentation method does indeed increase of piperidine alkaloid contents on mulberry leaves.

• Journal of Microbiology and Biotechnology
• /
• 제25권12호
• /
• pp.2100-2105
• /
• 2015

Probiotic bacteria must have not only tolerance against bile salt but also no genes for antibiotic resistance. Leuconostoc citreum is a dominant lactic acid bacterium in various fermented foods, but it is not regarded as a probiotic because it lacks bile salt resistance. Therefore, we aimed to construct a bile salt-resistant L. citreum strain by transforming it with a bile salt hydrolase gene (bsh). We obtained the 1,001 bp bsh gene from the chromosomal DNA of Lactobacillus plantarum and subcloned it into the pCB4170 vector under a constitutive P710 promoter. The resulting vector, pCB4170BSH was transformed into L. citreum CB2567 by electroporation, and bile salt-resistant transformants were selected. Upon incubation with glycodeoxycholic acid sodium salt (GDCA), the L. citreum transformants grew and formed colonies, successfully transcribed the bsh gene, and expressed the BSH enzyme. The recombinant strain grew in up to 0.3% (w/v) GDCA, conditions unsuitable for the host strain. In in vitro digestion conditions of 10 mM bile salt, the transformant was over 67.6% viable, whereas only 0.8% of the host strain survived.

• 한국약용작물학회지
• /
• 제20권5호
• /
• pp.331-338
• /
• 2012

In the present work, mulberry fruit extracts by four extraction processes, namely wet pressing extraction (WPE), hot-water extraction (HWE), enzymatic hydrolysis (EH), and lactic-acid bacteria fermentation (LBF) by Lactobacillus plantarum TO-2100, were analyzed for nutrients and functional compounds. The sugar contents of extracts by WPE, HWE, EH, and LBF were 12.0, 10.9, 14.5, and 14.3 brix, respectively, and the extraction yields by EH and LBF were 1.65 and 1.50 times higher than those by WPE. Among the organic acids, tartaric acid and malic acid contents were the highest in the extracts by WPE. Acetic acid was best extracted by LBF, and citric acid was best extracted by EH. Lactic acid was detected only in LBF. The extracts by EH showed the highest contents of all vitamins with an exception that the extracts by LBF showed the highest contents of the folic acid, vitamin B12, and vitamin C. We also noted that vitamin B group was not detected in the extracts by LBF. The extracts by EH showed the highest contents of all the amino acids, whereas LBF showed the lowest. Polyphenol contents of extracts by EH and LBF were 3.05 and 2.51 times more than those by WPE respectively. Anthocyanin contents were 7.66, 7.14 times higher for EH and LBF compare to WPE. We manufactured mulberry fruit granular teas with different compositions and tested them for their sensory characteristics. We found that 15% mulberry fruit extracts by enzymatic hydrolysis and 85% dextrin composition gave the most satisfactory result.

• 한국잠사곤충학회지
• /
• 제51권2호
• /
• pp.164-172
• /
• 2013

이 연구는 뽕잎을 전통방식의 당침 추출액과 Lactobacillus plantarum TO- 2100 유산균을 이용한 유산발효 추출액의 기능성 품질 특성을 조사하였다. 당침 추출액은 12주 동안 추출하였으며, 유산발효 추출액은 8주간 추출하였다. 당침 추출액 및 유산발효 추출액의 수율은 각각 27% 와 166% 였으며, 당 함량은 각각 43 $^{\circ}Brix$와 33 $^{\circ}Brix$였다. pH와 총 산도는 4.6, 0.45% 와 3.6, 1.17%였다. 유산발효 추출액의 유산균 생균수는 $1.2{\times}10^{10}$ $CFU/m{\ell}$으로 당침 추출액의 $2.8{\times}10^2$ $CFU/m{\ell}$ 보다 월등히 많았다. 유산발효 추출액이 amylase, cellulase, pectinase, protease 등 분해효소의 활성을 보인 반면, 당침 추출액은 분해효소의 활성을 나타내지 않았다. 유기산의 경우 malic acid, acetic acid, citric acid의 함량은 당침 추출액이 높은 반면, lactic acid 의 함량은 유산발효 추출액이 2.6배 높았다. 당침 추출액의 유리당은 glucose (200.93mg/g), fructose (236.32mg/g), sucrose (18.41mg/g) 등 GI값이 높은 단당으로 구성된 반면, 유산발효 추출액에서는 유리당이 검출되지 않았다. 기능성 성분인 polyphenol, anthocyanin 및 당질대사 저해물질인 piperidine alkaloid의 함량 또한 유산발효 추출액이 당침 추출액보다 높았다. 당질대사의 주 효소인 ${\alpha}$-glycosidase의 활성을 당침 추출액이 3.4% 저해한 반면 유산발효 추출액은 16.2% 저해 활성을 보였다. 이 결과로부터 전통방식의 당침 추출법에 비해 유산발효 추출법이 뽕잎의 수율 향상 및 기능성 성분의 함량 증진에 더 효과적이며, 이로 인한 대사기능장애의 예방 및 기능증진에 더 유효할 것으로 사료된다.