• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1441-1448
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• 2017

Antibacterial compounds are widely used in the treatment of human and animal diseases. The overuse of antibiotics has led to a rapid rise in the prevalence of drug-resistant bacteria, making the development of new antibacterial compounds essential. This study focused on developing a fast and easy method for identifying marine bacteria that produce antibiotic compounds. Eight randomly selected marine target bacterial species (Agrococcus terreus, Bacillus algicola, Mesoflavibacter zeaxanthinifaciens, Pseudoalteromonas flavipulchra, P. peptidolytica, P. piscicida, P. rubra, and Zunongwangia atlantica) were tested for production of antibacterial compounds against four strains of test bacteria (B. cereus, B. subtilis, Halomonas smyrnensis, and Vibrio alginolyticus). Colony picking was used as the primary screening method. Clear zones were observed around colonies of P. flavipulchra, P. peptidolytica, P. piscicida, and P. rubra tested against B. cereus, B. subtilis, and H. smyrnensis. The efficiency of colony scraping and broth culture methods for antimicrobial compound extraction was also compared using a disk diffusion assay. P. peptidolytica, P. piscicida, and P. rubra showed antagonistic activity against H. smyrnensis, B. cereus, and B. subtilis, respectively, only in the colony scraping method. Our results show that colony picking and colony scraping are effective, quick, and easy methods of screening for antibacterial compound-producing bacteria.

• Advances in Traditional Medicine
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• v.10 no.4
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• pp.304-309
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• 2010

Scutellaria pinnatifida A. Hamilt. (Lamiaceae) is an endemic Turkish herb. This plant is also endemic to Iran, and grows abundantly in other central and western Asian countries. Several species of the Scutellaria are known for their traditional uses in the treatment of hypertension, arteriosclerosis, inflammatory diseases, hepatitis, allergy, cancer and diarrhoea. Free-radical-scavenging property, antibacterial activity and brine shrimp toxicity of the n-hexane, dichloromethane (DCM) and methanol (MeOH) extracts of S. pinnatifida were assessed using the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay, the resazurin microtitre plate based assay, and the brine shrimp lethality assay, respectively. The DCM and MeOH extracts exhibited free-radical-scavenging property, with the $RC_{50}$ values of 0.362 and 0.127 mg/ml, respectively. Among the solid-phase extraction fractions of the MeOH extract, the 50% aqueous-MeOH fraction showed the highest level of free-radicalscavenging activity ($RC_{50}$ = 0.039 mg/ml). While the DCM extract showed low level of antibacterial activity against Bacillus subtilis and ampicillin-resistant Escherichia coli, the MeOH extract was active against B. cereus, B. subtilis, E. coli and ampicillin-resistant E. coli. However, the minimum inhibitory concentrations (MIC) of the MeOH extract against these bacterial strains were >10 mg/ml. None of the extracts showed any significant toxicity towards brine shrimps ($LD_{50}$ = > 1.00 mg/ml).

• Food Science and Biotechnology
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• v.15 no.6
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• pp.967-974
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• 2006

Cyclomaltodextrinases (CDases), maitogenic amylases, and neopullulanases share highly conserved primary structures and similar characteristics, and are thus classified into the same family. BLAST search has showed that a variety of bacterial strains harbor putative CDase family genes with several well-conserved motif amino acid sequences. In this study, four degenerate polymerase chain reaction (PCR) primer sets were designed for the detection of CDase genes, on the basis of their highly conserved amino acid blocks (WYQIFP, DGWRLD, LGSHDT, and KCMVW). The PCR detection conditions were optimized and the detection specificity of each for the primer sets was tested against the genomic DNAs isolated from 23 different Bacillus-associated species. Consequently, all tested primer sets evidenced successful amplification of specific PCR products in length, which share 55-98% amino acid sequence identity with known and putative CDases. The primers developed herein, therefore, can be applied for the easy and efficient detection and isolation of CDase family genes for the modification of functional food carbohydrates.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.851-855
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• 2006

Acarviosine-glucose (AcvGlc) is an ${\alpha}$-glucosidase inhibitor and has similar inhibitory activity to acarbose in vitro. We synthesized AcvGlc by treating acarbose with Bacillus stearothermophilus maltogenic amylase and fed C57BL/6J and db/db mice with diets containing purified AcvGlc and acarbose for 1 week. AcvGlc (50 and 100 mg/100 g diet) significantly reduced plasma glucose and triglyceride levels in db/db mice by 42 and 51 %, respectively (p<0.0001). The hypoglycemic and hypotriglyceridemic effects of AcvGlc were slightly, but significantly, greater than those seen with acarbose treatment (p<0.0001) in C57BL/6J mice. In an oral glucose tolerance test, glucose tolerance was significantly improved at all time points (p<0.01). The expression of two novel glucose transporters (GLUTs), GLUT10 and GLUT12, were examined by Western blot analysis. GLUT10 was markedly increased in the db/db livers. After AcvGlc treatment, the expression of hepatic GLUT10 was decreased whereas intestinal GLUT12 was significantly increased in both strains of mice. Our results show that AcvGlc improves plasma lipid and glucose metabolism slightly more than acarbose. Regulation of hepatic GLUT10 and intestinal GLUT12 may be important in controlling blood glucose levels.

• Journal of Ginseng Research
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• v.42 no.1
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• pp.57-67
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• 2018

Background: Ginseng contains many small metabolites such as amino acids, fatty acids, carbohydrates, and ginsenosides. However, little is known about the relationships between microorganisms and metabolites during the entire ginseng fermentation process. We investigated metabolic changes during ginseng fermentation according to the inoculation of food-compatible microorganisms. Methods: Gas chromatography mass spectrometry (GC-MS) datasets coupled with the multivariate statistical method for the purpose of latent-information extraction and sample classification were used for the evaluation of ginseng fermentation. Four different starter cultures (Saccharomyces bayanus, Bacillus subtilis, Lactobacillus plantarum, and Leuconostoc mesenteroide) were used for the ginseng extract fermentation. Results: The principal component analysis score plot and heat map showed a clear separation between ginseng extracts fermented with S. bayanus and other strains. The highest levels of fructose, maltose, and galactose in the ginseng extracts were found in ginseng extracts fermented with B. subtilis. The levels of succinic acid and malic acid in the ginseng extract fermented with S. bayanus as well as the levels of lactic acid, malonic acid, and hydroxypruvic acid in the ginseng extract fermented with lactic acid bacteria (L. plantarum and L. mesenteroide) were the highest. In the results of taste features analysis using an electronic tongue, the ginseng extracts fermented with lactic acid bacteria were significantly distinguished from other groups by a high index of sour taste probably due to high lactic acid contents. Conclusion: These results suggest that a metabolomics approach based on GC-MS can be a useful tool to understand ginseng fermentation and evaluate the fermentative characteristics of starter cultures.

• Parasites, Hosts and Diseases
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• v.35 no.2
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• pp.127-134
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• 1997

Transmission electron microscopy of an ArGnthnmoebo isolate (KA/LS) from a contact lens case revealed bacterial endosymbionts within cytoplasm of the amoebae. The Acnnthamoebn isolate belonged to the morphological group ll. Based on the polymerase chain reaction (PCR) - restriction fragment leilgth polymorphism (RFLP) of 185 ribosomal RNA coding DNA (rDNA) , the isolate was identified as A. Iwnunensis. Strain typing by isoenzyme analysis using isorlectric focusing (IEF) and mitochondrial (Ent) DNA RFLP revealed that the isolate was closely related with KA/Ll , the most predominant type of isolates from contact lens storage casas, KA/E2, a clinical isolate, KA/W4, previou:fly reported to host endosymbionts. and L3a strains of A. Iwnunensis. The endosymbionts were similar to those of KA/W4 in a.jpects that they were randomly distributed in both trophozoites and cysts, and were rod-shaped bacteri3 measuring approximately 1.38 x 0.50 ㎛. But the number of endosymbionts per amoeba was significantly lower than that of KA/W4. They were neither limited by phagosomal membranes nor included in lacunae- like stnlcture.

• Korean journal of food and cookery science
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• v.14 no.5
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• pp.498-502
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• 1998

In order to develop a natural food preservative, freeze dried plantain (Plantago asiatica L.) was extracted with several solvents, and the antimicrobial activity was investigated. The methanol extract exhibited antimicrobial activites against five strains of bacteria such as Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Vibrio parahaemolyticus. The methanol extract at the concentration of 1.0 mg/ml completely inhibited the growth of B. subtilis and V. parahaemolyticus. Antimicrobial activity of the ethylacetate fraction from the methanol extract was the strongest compared with those of other solvent fractions such as n-hexane, chloroform, n-butanol and water. The ethylacetate fraction showed the inhibitory effect at the concentration of 0.5 mg/disc on the growth of B. subtilis and V. parahaemolyticus.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.8
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• pp.1159-1168
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• 2012

The experiment was carried out to investigate the effects of Alisma canaliculatum with probiotics (ACP) on the growth performance, meat composition, oxidative stability, and fatty acid composition of broiler meat. Sixteen probiotic strains were tested for their levels of acid, bile, and heat tolerance. Among them, Lactobacillus acidophilus KCTC 3111, Enterococcus faecium KCTC 2022, Bacillus subtilis KCTC 3239, and Saccharomyces cerevisiae KCTC 7928 were selected for use in ACP. Exactly 140 Ross broiler chicks were assigned to four dietary treatments in five replications for 5 wks in a completely randomized design. The dietary treatments were NC (Negative control; basal diet), PC (Positive control; basal diet with 0.005% Chlortetracycline), ACP-0.5% (basal diet with 0.5% ACP powder), and ACP-1% (basal diet with 1% ACP powder). According to the results, body weight of the broilers increased, and feed conversion ratio improved in the ACP-0.5% group compared to the NC group (p<0.05). Crude protein content of breast meat was higher (p<0.05) in the ACP-0.5% group, whereas crude fat content of thigh meat was lower (p<0.05) in the supplemented groups. Breast meat absolute and relative weights were both higher (p<0.05) in the ACP groups compared to the control group. Further, ACP diets increased gizzard and decreased large intestine relative weights, whereas kidney relative weight decreased upon the addition of a higher level (1%) of ACP (p<0.05). Thiobarbituric acid reactive substances values of breast and thigh meats were reduced (p<0.05) by ACP supplementation compared to control. Regarding the fatty acid composition of breast meat, arachidonic acid, docosahexaenoic acid, PUFA, and n6 fatty acid levels decreased (p<0.05) in the ACP groups, whereas the levels of linoleic acid, PUFA, PUFA/SFA, and n6 fatty acid in thigh meat decreased (p<0.05) by ACP and PC diets. It can be suggested based on the study results that ACP-0.5% diet could be an effective feed additive for broilers.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.14-21
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• 2005

By using PCR with nirS gene primers, three nirSharboring denitrifying bacteria (strain N6, strain N23, and strain R13) were newly isolated from activated sludge of a weak municipal wastewater treatment plant. Small-subunit rRNA gene-based analysis indicated that strain N6, strain N23, and strain R13 were closely related to Arthrobacter sp.,Staphylococcus sp., and Bacillus sp., respectively. In an attempt to identify their roles in biological nitrate and nitrite removal from sewage, we investigated their specific denitrification rates (SDNRs) for $NO_-^3$ - and $NO_-^2$ - in various cultures. All purecultures of each isolated nirS-harboring bacterial strain could remove $NO_-^3$ - and $NO_-^2$ - simultaneously in high efficiency, and the carbon requirements for $NO_-^3$ - removal of strain N6 and strain R13 were effectively low at 3.1 and 4.1 g COD/g $NO_3N$, respectively. In the case of mix-cultures of the strains (N6+N23, N6+R13, N23+R13, and N6+N23+R13), their SDNRs for $NO_-^3$ - were also effective, and their carbon requirements for $NO_-^3$ - removal were also effective at 3.0- 3.8 g COD/g NO3N. However, all tested mix-cultures accumulated $NO_-^2$ - in their culture media. On the other hand, the continuous culture of activated sludge mixed with strain N6 showed no significant increase of $NO_-^3$ - removal in comparison with strain N6's pure culture. These results suggest that nitrate and nitrite removal in biological wastewater treatment might be dependent on complicated bacterial interactions, including several effective denitrifying bacteria isolated in this study, rather than the specific bacterial types present and the number of bacterial types in activated sludge.

• Nutrition Research and Practice
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• v.10 no.3
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• pp.282-287
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• 2016

BACKGROUND/OBJECTIVES: Jerusalem artichoke has inhibitory activity against ${\alpha}$-glucosidase and decreases fasting serum glucose levels, which may be related to its fructan content. The biological activity of fructan can be influenced by the degree of polymerization. Thus, in this study, the inhibitory effects of original and fermented purple Jerusalem artichoke (PJA) on ${\alpha}$-glucosidase were compared in vitro. Additionally, the anti-diabetes effect of Lactobacillus plantarum-fermented PJA (LJA) was studied in a non-insulin-dependent diabetes mellitus animal model (C57BIKsJ db/db). MATERIALS/METHODS: The water extract of PJA was fermented by L. plantarum, and two strains of Bacillus subtilis to compare their anti-${\alpha}$-glucosidase activities in vitro by ${\alpha}$-glucosidase assays. The anti-diabetes effect of LJA was studied in a non-insulin-dependent diabetes mellitus animal model (C57BIKsJ db/db) for seven weeks. During the experiment, food intake, body weight, and fasting blood glucose were measured every week. At the end of the treatment period, several diabetic parameters and the intestinal ${\alpha}$-glucosidase activity were measured. RESULTS: The LJA showed the highest ${\alpha}$-glucosidase inhibitory activity in vitro. In the in vivo study, it resulted in a significantly lower blood glucose concentration than the control. Serum insulin and HDL cholesterol levels were significantly higher and the concentrations of triglycerides, non-esterified fatty acids, and total cholesterol were significant lower in mice treated with LJA after seven weeks. In addition, the intestinal ${\alpha}$-glucosidase activity was partially inhibited. CONCLUSIONS: These results suggested that LJA regulates blood glucose and has potential use as a dietary supplement.