• Korean journal of food and cookery science
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• v.16 no.6
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• pp.557-567
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• 2000

An optional ingredient, jasoja(Perillae semen), was adopted to improve the quality of Dongchimi. The final weight percentage of jasoja in Dongchimi was adjusted to 0, 0.25, 0.5, 0.75, or 1.0%, per radish, and sensory and microbiological characteristics were determined during fermentation at 10 for 45 days. The effect was varied depending on the amounts of jasoja, but Dongchimi fermented with 0.5% jasoja was most favored for color, flavor, taste, texture, and overall acceptability in sensory evaluation. According to a quantitative descriptive analysis for the product, the liquid portion of Dongchimi steadily became clearer and less sour in proportion to the amount of added jasoja. However, a strong off-taste was detected from 1.0% treatment. The viable cell numbers of total and lactic acid bacteria drastically increased during the first 2 days, and then gradually increased to their maximum values during fermentation and slowly decreased at the later stage. Dongchimi with 0.5% treatment showed a distinctive high number of microorganisms at the 15th-day of fermentation and this trend was maintained until the completion of fermentation. The lactic acid bacteria isolated and identified from Dongchimi were; Lactobacillus brevis, Lactobacillus plantarum, Leuconostoc mesenteroides, Lactococcus faecalis, and Lactococcus lactis. The combined number of Lactobacillus brevis and Lactobacillus plantarum began to increase right after preparation to as much as 10$\^$7/CFU/㎖, then decreased to 10-10$^3$CFU/㎖ afterward. This study showed that the addition of jasoja retarded the initial fermentation of Dongchimi; however, too much jasoja at above 1% weight level per Chinese radish might accelerate fermentation at the later fermentation stage and shoud be avoided. A comparable fermentation pattern was observed among the samples; however, more acceptable Dongchimi could be prepared by fermenting for 11 to 30 days at 0.5% jasoja concentration per radish.

• Journal of Ginseng Research
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• v.34 no.2
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• pp.104-112
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• 2010

Fermented red ginseng (FRG) was prepared by inoculating 0.1% Lactobacillus fermentum NUC-C1 and fermenting them at $40^{\circ}C$ for 12 hours. The ginsenoside contents of FRG were increased compared with those of red ginseng (RG). Moreover, the levels of the ginsenosides Rg2, Rg3, and Rh2 in FRG increased significantly. In an oral glucose tolerance test (OGTT), blood glucose levels were lower in animals fed with RG and FRG extracts than in normal controls. In particular, FRG extracts in OGTT were superior to RG extracts. The antidiabetic effects of FRG in streptozotocin (STZ)-induced diabetic rats were investigated. Rats were divided into four groups: normal control, diabetes mellitus (DM), FRG administered at 100 mg/kg, and FRG administered at 200 mg/kg groups. FRG extracts were orally administered to each treatment group for 3 weeks, and blood glucose, insulin, and lipid levels of each group were determined. Orally administered FRG extracts significantly reduced blood glucose levels and increased plasma insulin levels in diabetic rats. Additionally, the activities of disaccharidases, including sucrase, lactase, and maltase, were decreased significantly in the FRG groups. FRG groups also had reduced triglyceride and total cholesterol levels, compared with the DM group. These results suggest that FRG may have antidiabetic effects in STZ-induced diabetic rats.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.1
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• pp.100-108
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• 2011

The object of this study was two. One was if Polygonati Rhizoma preparata had a benzo(a)pyrene, the other was to evaluate the single dose toxicity of 9 repetitive steaming and fermenting processed Polygonati Rhizoma, dried root parts of Polygonati Rhozoma preparata extract, in male and female mice. We measured a content of benzo(a)pyrene in Polygonati Rhozoma preparata using a method with HPLC/FLD. And for single dose toxicity, aqueous extracts of Polygonati Rhozoma preparata (EPP; Yield = 35.4 %) was administered to female and male ICR mice as an oral dose of 2,000, 1,000 and 500 mg/kg (body weight) according to the recommendation of Korea Food and Drug Administration (KFDA) Guidelines. Animals were monitored for the mortality and changes in body weight, clinical signs and gross observation during 14 days after dosing, upon necropsy; organ weight and histopathology of 12 principle organs were examined. As results, we could not find any mortality, clinical signs, and changes in the body and organ weight except for slight soft feces sporadically detected in EPP treated male mice at 1 day after administration. In addition, no EPP-treatment related abnormal gross findings and changes in histopathology of principle organs were detected except for some sporadic accidental findings. The results obtained in this study suggest that benzo(a)pyrene was not existed in Polygonati Rhozoma preparata and the 50% lethal dose and approximate lethal dose of EPP aqueous extracts in both female and male mice were considered as over 2,000 mg/kg, the limited highest dosage recommended by KFDA Guidelines. However, it also observed that the possibilities of digestive disorders, like soft feces when administered over 500 mg/kg of EPP aqueous extracts in the present study.

• Korean Journal of Clinical Laboratory Science
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• v.45 no.1
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• pp.21-25
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• 2013

Acinetobacter baumannii is an aerobic, gram-negative and glucose-non-fermenting bacterium, which has emerged as a serious opportunistic pathogen. Many clinical microbiology laboratories use the Vitek 2 system for the routine antimicrobial susceptibility testing process, including testing on A. baumannii isolates. However, in case of amikacin, it is now recommended to perform additional antimicrobial susceptibility testing for A. baumannii strains due to the relatively lower minimum inhibitory concentration (MIC) in the Vitek 2 system compared to conventional reference methods. In our study, we assessed MIC for amikacin susceptibility testing of A. baumannii isolates in the Vitek 2 system, the agar dilution, Etest, and disk diffusion method. We collected 40 gentamicin-resistant, A. baumannii strains (amikacin MIC by Vitek 2:${\leq}2{\mu}g/mL$, 2 isolates; $4{\mu}g/mL$, 34 isolates; $8{\mu}g/mL$, 4 isolates) from a University hospital and compared the Vitek 2 system to other reference methods for testing susceptibility to amikacin. The Vitek 2 system showed major errors in all of the 40 isolates, yielding a low MIC. The results of our study strongly suggested that the Vitek 2 system was not a reliable method to test the MICs of gentamicin; ranging from ${\geq}16{\mu}g/mL$ for amikacin susceptibility. Other tests, such as agar dilution, Etest, or disk diffusion methods, should be paralleled to determine the MIC of amikacin in A. baumannii.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.1
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• pp.27-31
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• 2000

Characteristics of ethanol production by a xylose-fermenting yeast, Pichia stipitis Y-7124, were studied. The sugar consumption rate and specific growth rate were higher in the glucose-containing medium than in the xylose-containing medium. Specific activities of xylose reductase and xylitol dehydrogenase were higher in the medium with xylose than glucose, suggesting their induction by xylose. Maximum specific growth rate and ethanol yield were achieved at 30 g xylose/L concentration without formation of by-products such as xylitol and acetic acid whereas a maximum ethanol concentration was obtained at 130 g/L xylose. Adding a respiratory inhibitor, rotenone, increased a maximum ethanol concentration by $10\%$ compared with the control experiment. In order to evaluate the pattern of ethanol inhibition on specific growth rate, a kinetic model based on Luong's equations was applied. The relationship between ethanol concentration and specific growth rate was hyperbolic for glucose and parabolic for xylose. A maximum ethanol concentration at which cells did not grow was 33.6 g/L for glucose and 44.7 g/L for xylose.

• Microbiology and Biotechnology Letters
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• v.16 no.6
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• pp.489-493
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• 1988

To obtain a new yeast strain that is able to efficiently produce ethanol from starch, the glucoamylase gene of Saccharomyces diastaticus was transformed into S. cerevisiae without a cloning vector. The competent cells of S. cerevisiae, induced by the treatment of Li$_2$SO$_4$, were transformed with the partial BamHI-digests of chromosomal DNA of S. diastaticus, and the transformants were selected by their abilities to utilize and ferment starch. The transformants, which appeared at a frequency of 8.5$\times$10$^{-7}$, were able to withstand up to 800 ppm of copper sulfate like the recipient and retained the phenotypic expression of the recipient with the exception of the acquisition of STA gene and MAL gene, as regards fermentation of carbohydrates. The enzymatic properties of glucoamylases produced by transformants were very similar to those produced by S. diastaticus as based on optimium pH and temperature.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.487-495
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• 1998

The mycotoxins, $Aflatoxin\;B_1(B)$ and Ochratoxin A(A), were measured from the various mejus manufactured under the artificial or natural conditions by the indirect competitive ELISA; The various fungi isolated from the Korean traditional home (KTH) made meju collected were observed to produce each mycotoxin mentioned above in the toxin producing broth, but only few in the sterilized cereals of soybean under the artificial conditions. Thus, the isolated fungi were not found to produce both A and B toxins in the artificial conditions. Particularly, the any mycotoxin was not determined at the range of 0.01 to 100 ng per gm of the mejus made under the conditions of KTH widely collected in Korea. The mycotoxins produced by the meju-fermenting fungi were seemed or speculated to be degraded in KTH's mejus under the natural conditions. The species of Mucor involved in the initial stage of fermentation were discussed to be important in the fermentations of KTH mejus.

• Korean Journal of Microbiology
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• v.43 no.2
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• pp.142-146
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• 2007

Panax ginseng has been drawing world-wide attention since it was used for medicinal purposes and its effects was discovered in scientific manners. However, it is necessary to develope new ginseng products as functional foods to compete with western ginseng. Fermented ginseng could be an excellent solution, where useful probiotics are provided and ginsenosides are specifically transformed to functional forms. In this study, we investigated the growth and ginsenoside biotransformation by 21 Bacillus strains isolated from Chongkukjang and 12 lactic acid bacteria. 2.5% (w/v) and 1% (w/v) of ginseng were used in culture media containing only ginseng powder as a sole nutrient source, and their biotransformation abilities were tested after the growths were checked. All used Bacillus strains and lactic acid bacteria were able to grow well in ginseng powder media at higher levels than $10^{7}\;CFU/ml$. Most of Bacillus strains displayed ginsenoside transformation in a strain-specific manner. Therefore, the results of this study demonstrated that the strains tested in this study could be used as potential starters for the ginseng fermentation.

• Journal of Microbiology and Biotechnology
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• v.25 no.1
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• pp.137-142
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• 2015

Trimethoprim-sulfamethoxazole (TMP-SMX) has been used for the treatment of urinary tract infections, but increasing resistance to TMP-SMX has been reported. In this study, we analyzed TMP-SMX resistance genes and their relatedness with integrons and insertion sequence common regions (ISCRs) in uropathogenic gram-negative bacilli. Consecutive nonduplicate TMP-SMX nonsusceptible clinical isolates of E. coli, K. pneumoniae, Acinetobacter spp., and P. aeruginosa were collected from urine. The minimal inhibitory concentration was determined by Etest. TMP-SMX resistance genes (sul and dfr), integrons, and ISCRs were analyzed by PCR and sequencing. A total of 45 E. coli (37.8%), 15 K. pneumoniae (18.5%), 12 Acinetobacter spp. (70.6%), and 9 Pseudomonas aeruginosa (30.0%) isolates were found to be resistant to TMP-SMX. Their MICs were all over 640. In E. coli and K. pneumoniae, sul1 and dfr genes were highly prevalent in relation with integron1. The sul3 gene was detected in E. coli. However, in P. aeruginosa and Acinetobacter spp., only sul1 was prevalent in relation with class 1 integron; however, dfr was not detected and sul2 was less prevalent than in Enterobacteriaceae. ISCR1 and/or ISCR2 were detected in E. coli, K. pneumoniae, and Acinetobacter spp. but the relatedness with TMP-SMX resistance genes was not prominent. ISCR14 was detected in six isolates of E. coli. In conclusion, resistance mechanisms for TMP-SMX were different between Enterobacteriaceae and glucose non-fermenting gram-negative bacilli. Class 1 integron was widely disseminated in uropathogenic gram-negative baciili, so the adoption of prudent use of antimicrobial agents and the establishment of a surveillance system are needed.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.4
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• pp.59-65
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• 2009

The antimicrobial activity-possessing materials were screened in the cell free supernatant (CFS) of fourteen lactic acid-fermenting strains isolated from pig's intestine. Each cell free supernatant of cultured strains was treated with various proteinases, heat, and/or alkali (NaOH). The antimicrobial activities were remained even after the enzyme and heat treatment but disappeared after neutralization with 1M NaOH, implying that the materials would be organic acids rather than proteins. Further purification of CFS through solid phase extraction using Sep-pak $C_{18}$ Cartridges and high performance anion exchange chromatography using Bio-LC system revealed that four organic acids, such as oxalic acid, citric acid, lactic acid, and acetic acid, were the main materials for the activity. Lactic acid was the highest amount in all organic acids, ranging from 54% to 77%. This strongly implies that the lactic acid would be the primary material for the antimicrobial activity in all tested strains.