• Journal of Life Science
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• v.25 no.1
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• pp.75-83
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• 2015

Curcuma longa L. (CL), a traditional medicinal plant, is well known as a functional food ingredient. The major component of CL is a curcumin of anthocyanin family that has multi-functions such as antimicrobial, anticancer, and antioxidant activity. In this study, fermented milk containing CL was prepared using a mixed strain culture (Bifidobacterium bifidus, Streptococcus thermophilus, Lactobacillus acidophilus), and its physicochemical properties were characterized. In addition, inflammatory cytokine-modulating effects of the fermented milk were also investigated. As regards the properties of fermented milk, the growth rate of lactic acid bacteria in fermented milk containing CL was found to be remarkably more rapid than control. During fermentation, caseins and whey proteins were observed to be partially hydrolyzed, and lactic acid and acetic acid were produced in larger amounts than in the control. The sensory score of fermented milk containing CL was lower than control, owing to its bitter taste and strong flavor. RAW 264.7 cells treated with CL fermented milk supernatant showed no cytotoxicity. Inflammatory cytokines such as tumor necrosis factor-alpha (TNF-${\alpha}$) and interleukin-6 (IL-6) were significantly produced by fermented milk with CL, compared to control. The secretion of nitric oxide (NO) from RAW 264.7 cells significantly increased relative to the control. Results from the present study suggested that CL could be used as a natural immunomodulating ingredient for making yogurts, beverages, and other products.

• Journal of Microbiology and Biotechnology
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• v.25 no.10
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• pp.1751-1760
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• 2015

Mucin2 (MUC2), an important regulatory factor in the immune system, plays an important role in the host defense system against bacterial translocation. Probiotics known to regulate MUC2 gene expression have been widely studied, but the interactions among probiotic, pathogens, and mucin gene are still not fully understood. The aim of this study was to investigate the role of MUC2 in blocking effects of probiotics on meningitic E. coli-induced pathogenicities. In this study, live combined probiotic tablets containing living Bifidobacterium, Lactobacillus bulgaricus, and Streptococcus thermophilus were used. MUC2 expression was knocked down in Caco-2 cells by RNA interference. 5-Aza-2'-deoxycytidine (5-Aza-CdR), which enhances mucin-promoted probiotic effects through inducing production of Sadenosyl-L-methionine (SAMe), was used to up-regulate MUC2 expression in Caco-2 cells. The adhesion to and invasion of meningitic E. coli were detected by competition assays. Our studies showed that probiotic agents could block E. coli-caused intestinal colonization, bacteremia, and meningitis in a neonatal sepsis and meningitis rat model. MUC2 gene expression in the neonatal rats given probiotic agents was obviously higher than that of the infected and uninfected control groups without probiotic treatment. The prohibitive effects of probiotic agents on MUC2-knockdown Caco-2 cells infected with E44 were significantly reduced compared with nontransfected Caco-2 cells. Moreover, the results also showed that 5-Aza-CdR, a drug enhancing the production of SAMe that is a protective agent of probiotics, was able to significantly suppress adhesion and invasion of E44 to Caco-2 cells by upregulation of MUC2 expression. Taken together, our data suggest that probiotic agents can efficiently block meningitic E. coli-induced pathogenicities in a manner dependent on MUC2.

• Food Science and Preservation
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• v.31 no.3
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• pp.474-485
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• 2024

The purposes of this study were to isolate the potential Lacticaseibacillus spp. from the feces of infants before weaning, to investigate the safety of antibiotics resistance and beta-haemolysis, and to evaluate the anti-bacterial and anti-inflammatory effects between the selected strains and Oenanthe javanica (Oj) fermented by them. As a result of analyzing the intestinal microbial community among the stools of four infants, the genus Bifidobacterium was the most dominant, but Lacticaseibacillus (L.) rhamnosus was the most frequently isolated because of the easy culture. Nine test strains, including Lactobacillus rhamnosus LGG (ATCC 53103) as the positive control, were sensitive against 8 kinds of antibiotics without vancomycin in comparison with the cut-off values at the European Food Safety Authority (EFSA), and there was no hemolysis. In the antibacterial activity experiment, the Lacticaseibacillus rhamnosus L22-FR28 (L28, KACC 92513P) strain and Oj+L28 ferment showed significantly (p<0.05) higher activities than LGG against Bacillus cereus and Staphylococcus aureus. Additionally, these decreased the activity of the NF-kB/AP-1 transcription factor and inhibited the nitric oxide and cytokines (TNF-α and IL-6) produced in macrophage RAW cells stimulated by lipopolysaccharide (LPS). Consequently, the L. rhamnosus L28 strain and Oenanthe javanica+L. rhamnosus L28 (Oj+L28) ferment selected with the high anti-inflammatory effect will improve health functionality after more research, such as the verification of animal level and identification of mechanism on an anti-inflammatory.