• Journal of Microbiology and Biotechnology
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• v.23 no.12
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• pp.1673-1682
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• 2013

Citrobacter sp. is a cause of significant opportunistic nosocomial infection and is frequently found in human and animal feces, soil, and sewage water, and even in industrial waste or putrefaction. Biofilm formation is an important virulence trait of Citrobacter sp. pathogens but the process and characteristics of this formation are unclear. Therefore, we employed in vitro assays to study the nutritional and environmental parameters that might influence biofilm formation of C. werkmanii BF-6 using 96-well microtiter plates. In addition, we detected the relative transcript levels of biofilm formation genes by RT-PCR. Our results indicated that the capacity of C. werkmanii BF-6 to form biofilms was affected by culture temperature, media, time, pH, and the osmotic agents glucose, sucrose, NaCl, and KCl. Confocal laser scanning microscopy results illustrated that the structure of biofilms and extracellular polysaccharide was influenced by 100 mM NaCl or 100 mM KCl. In addition, nine biofilm formation genes (bsmA, bssR, bssS, csgD, csgE, csgF, mrkA, mrkB, and mrkE) were found to contribute to planktonic and biofilm growth. Our data suggest that biofilm formation by C. werkmanii BF-6 is affected by nutritional and environmental factors, which could pave the way to the prevention and elimination of biofilm formation using proper strategies.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.252-259
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• 2004

Objectives : Halitosis is a common human condition, exact pathophysiological mechanisms of which are unclear. This study, which investigates halitosis patients' characteristics and their related factors, was done with intent to establish a foundation for the Oriental Medical treatment of halitosis. Methods : 329 patients were surveyed by reviewing medical charts and questionnaires from the East-West Halitosis Clinic of Kyunghee Medical Center from May 1, 2001 to December 31, 2002. Sex, age, illness duration, coating on the tongue, postnasal drip, globus pharyngeus, indigestion, condition of feces, halimeter measurements and results of the salivary scans were analyzed. Results : The thick and yellowish coating on the tongue was not a major cause of halitosis in the patients studied. Among the halitosis patients, 21.6% complained of postnasal drip, 15.6% of globus pharyngeus, 37.4% of indigestion, and 23.8% of diarrhea or constipation, suggesting the possibility of extra-oral origin in oral malodor. Conclusions : This study suggests that, when treating halitosis patients, intra-oral causes of halitosis aside, Oriental Medical treatments such as solving qi-stasis(氣鬱), augmenting deficiency of the spleen qi(碑氣虛) and treating gastric fever(胃熱) constitute effective management for oral malodor patients.

• Parasites, Hosts and Diseases
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• v.50 no.4
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• pp.391-394
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• 2012

The prevalence of liver and intestinal fluke infections was determined by surveying inhabitants of Hengxuan, Fusui, and Shanglin villages which were known to be endemic for liver flukes in Guangxi, China in May 2010. A total of 718 people were examined for helminth eggs by the Kato-Katz thick smear technique, ultrasonography, immunoaffinity chromatography, and DNA sequencing. The overall egg positive rate was found to be 59.6% (28.0-70.6%) that included mixed infections with liver and intestinal flukes. Cases showing higher than 20,000 eggs per gram of feces (EPG) were detected between 1.3% and 16.2%. Ultrasonographic findings exhibited overall 28.2% (72 of 255 cases) dilatation rate of the intrahepatic bile duct. Clonorchis sinensis infection was detected serologically in 88.3% (38 of 43 cases) among C. sinensis egg positive subjects by the immunoaffinity chromatography using a specific antigen for C. sinensis. For differential diagnosis of the liver and intestinal flukes, more precise PCR and nucleotide sequencing for copro-DNA were performed for 46 egg positive cases. Mixed infections with C. sinensis and Metagonimus yokogawai were detected in 8 of 46 egg positive cases, whereas 29 specimens were positive for Haplorchis taichui. Ultrasonographic findings and immunoaffinity chromatography results showed usefulness, even in a limited way, in figuring out of the liver fluke endemicity.

• Food Science of Animal Resources
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• v.32 no.5
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• pp.635-643
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• 2012

As an appraisal for the application of a new starter culture, more than 200 lactic acid bacteria strains were isolated from raw milk and healthy human feces. The strains showing excellent growth and acid production ability in 10% skim milk media were selected and identified as Lactobacillus casei based on the results of their API carbohydrate fermentation patterns, as well as 16S rDNA sequence analysis. To assess the effect of L. casei strains on irritable bowel disease (IBD), the inhibitory effect of the selected strains against the nitric oxide (NO) production of lipopolysaccharide (LPS)-stimulated RAW 264.7 cells was measured. Among the tested L. casei strains, L. casei MCL was observed to have the greatest NO inhibitory activity. Additionally, L. casei MCL was found to inhibit mRNA expression of pro-inflammatory cytokines (interleukin-$1{\beta}$, IL-6, TNF-${\alpha}$), as well as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) involved in pathophysiologic processes such as inflammation. The mRNA expression of anti-inflammatory cytokines, including IL-10 and transforming growth factor-$1{\beta}$ (TGF-${\beta}$) of L. casei MCL, was confirmed using quantitative real-time PCR. In conclusion, L. casei MCL showed decreases in the expression of pro-inflammatory cytokines and up-regulated expression of the anti-inflammatory cytokine.

• Korean journal of food and cookery science
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• v.26 no.4
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• pp.469-474
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• 2010

In this study, we isolated two species of bacteria for the powerful biotrasnformation of ginsenosides from Kimchi and human feces. Using biochemical tests and 16s rRNA sequencing, the selected strains were identified as Latobacillusplantarum (CKDHC0801) and Lactobacillussakei (CKDHC0802). Changes in cell growth and pH were examined in red ginseng. CKDHC 0801 and CKDHC 0802 reached their maximum growth phase after 24 hr and 48 hr, respectively, whereas the combined culture of CKDHC 0801 and CKDHC 0802 showed higher cell growth than bacterial strain alone. During fermentation of CKDHC 0801 and the combined culture, the pH values decreased from 5.2 to 4.2 after 24 hr, but CKDHC 0802 reached pH of 4.2 after 3day. The identities of ginsenosides were biotransferred from high molecular (Rg1 and Rb2) to low molecular (Rg3, Rg5, Rk1, PPD) by fermentation of both bacteria. Therefore, the results of this study demonstrate that CKDHC 0801 and CKDHC 0802 could be used to enhance to effects of red ginseng.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.836-843
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• 2014

Obesity, a condition in which an abnormally large amount of fat is stored in adipose tissue, causing an increase in body weight, has become a major public health concern worldwide. The purpose of this study was to optimize the process for fermented milk for the production of a functional product with an anti-obesity effect by using Lactobacillus plantarum Q180 isolated from human feces. We used a 3-factor, 3-level central composite design (CCD) combined with the response surface methodology (RSM). Concentration of skim milk powder (%, $X_1$), incubation temperature ($^{\circ}C$, $X_2$), and incubation time (h, $X_3$) were used as the independent factors, whereas pH (pH, $Y_1$), anti-lipase activity (%, $Y_2$) and anti-adipogenetic activity (%, $Y_3$) were used as the dependent factors. The optimal conditions of fermented milk for the highest anti-lipase and anti-adipogenetic activity with pH 4.4 were the 9.5% of skim milk powder, $37^{\circ}C$ of incubation temperature, 28 h of incubation time. In the fermentation condition, the predicted values of pH, anti-lipase activity and anti-adipogenetic activity were 4.47, 55.55, and 20.48%, respectively. However, the actual values of pH, anti-lipase activity and anti-adipogenetic activity were 4.50, 52.86, and 19.25%, respectively. These results demonstrate that 9.5% of skim milk powder and incubation at $37^{\circ}C$ for 28 h were the optimum conditions for producing functional fermented milk with an anti-obesity effect.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1464-1467
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• 2006

Artemisia princeps Pampanini, which is named as Sajabalssuk (SJ-1) in Korea, was fermented with lactic acid bacteria (LAB), and their antiallergic activities were investigated. When SJ-l was fermented with some LAB isolated from human feces, the inhibition of NO production in RAW264.7 cells and antioxidant activities of SJ-1 were not affected. However, the inhibitory activity of SJ-1 against degranulation of RBL-2H3 cells induced by IgE was increased by LAB fermentation. Among the LAB tested, Bifidobacterium infantis K-525 provided the most potent inhibitory effect of SJ-1 against degranulation of RBL-2H3 cells. SJ-1 extract fermented with B. infantis K-525 (F-SJ-1) potently inhibited the mouse passive cutaneous anaphylaxis reaction induced by IgE with antigen, skin dermatitis induced by 12-O-tetradecanoylphorbol-13-acetate, and scratching behaviors induced by compound 48/80. These inhibitory activities of F-SJ-1 were more potent than those of SJ-1. These findings suggest that the inhibition of SJ-1. extract against IgE-induced allergic diseases, such as rhinitis and asthma, can be enhanced by LAB fermentation.

• Journal of Microbiology and Biotechnology
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• v.24 no.7
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• pp.979-986
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• 2014

Plant pathogenic RNA viruses are present in a variety of plant-based foods. When ingested by humans, these viruses can survive the passage through the digestive tract, and are frequently detected in human feces. Kimchi is a traditional fermented Korean food made from cabbage or vegetables, with a variety of other plant-based ingredients, including ground red pepper and garlic paste. We analyzed microbial metatranscriptome data from kimchi at five fermentation stages to identify plant RNA virus-derived sequences. We successfully identified a substantial amount of plant RNA virus sequences, especially during the early stages of fermentation: 23.47% and 16.45% of total clean reads on days 7 and 13, respectively. The most abundant plant RNA virus sequences were from pepper mild mottle virus, a major pathogen of red peppers; this constituted 95% of the total RNA virus sequences identified throughout the fermentation period. We observed distinct sequencing read-depth distributions for plant RNA virus genomes, possibly implying intrinsic and/or technical biases during the metatranscriptome generation procedure. We also identified RNA virus sequences in publicly available microbial metatranscriptome data sets. We propose that metatranscriptome data may serve as a valuable resource for RNA virus detection, and a systematic screening of the ingredients may help prevent the use of virus-infected low-quality materials for food production.

• Korean Journal of Agricultural Science
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• v.21 no.1
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• pp.28-36
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• 1994

Studies on the food-safety of pheasant and mallard, which belong to wild fowl as new meat resources. were carried out. The results were summarized as follows : 1. Food poisoning bacteria including Salmonella spp, was not detected from the inspections of small intestine, cecum, and rectum. 2. Parasite inspection tests on blood, feces, digestive organ, and thoracic organs were negative. 3. Antibiotic residues from the carcass muscle by simplified disk methods were not detected. 4. Seven different pesticide residue tests, such as DDT and BHT, on the muscle and liver were negative. 5. Four different kinds of toxic heavy metals such as Cd were much lower than the permissible concentration. Studies on the food safety tests and inspections from the pheasant and mallard were revealed that from taking this new food resources, the toxicities would be very low for the human health by the direct influences.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1705-1713
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• 2012

A gene encoding ${\beta}$-glucosidase was cloned from Weissella cibaria 37, an isolate from human feces. Sequence analysis showed that the gene could encode a protein of 415 amino acids in length, and the translated amino acid sequence showed homology (34-31%) with glycosyl hydrolase family 1 ${\beta}$-glucosidases. The gene was overexpressed in E. coli BL21(DE3) using pET26b(+) and a 50 kDa protein was overproduced, which matched well with the calculated size of the enzyme, 49,950.87 Da. Recombinant ${\beta}$-glucosidase was purified by using a his-tag affinity column. The purified ${\beta}$-glucosidase had an optimum pH and a temperature of 5.5 and $45^{\circ}C$, respectively. Among the metal ions (5mM concentration), $Ca^{2+}$ slightly increased the activity (108.2%) whereas $Cu^{2+}$ (46.1%) and $Zn^{2+}$ (56.7%) reduced the activity. Among the enzyme inhibitors (1 mM concentration), SDS was the strongest inhibitor (16.9%), followed by pepstatin A (45.2%). The $K_m$ and $V_{max}$ values of purified enzyme were 4.04 mM and 0.92 ${\mu}mol/min$, respectively, when assayed using pNPG (p-nitrophenyl-${\beta}$-D-glucopyranoside) as the substrate. The enzyme liberated reducing sugars from carboxymethyl cellulose (CMC).