• Journal of Food Hygiene and Safety
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• v.28 no.4
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• pp.306-311
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• 2013

This study was conducted to investigate spoilage bacteria on organic and conventional fresh produce in Korea. Three samples (perilla leaf, cabbage, and romaine lettuce) of organic and conventional fresh produce were stored at $4^{\circ}C$ for 14 days and examined for spoilage bacteria on TSA. Isolated bacteria from organic and conventional fresh produces were identified using 16S rRNA sequencing method. Population of total aerobic bacteria on conventional perilla leaf, cabbage, and romaine lettuce were 7.59, 7.01, and $5.84{\log}_{10}CFU/g$, and populations of total aerobic bacteria were 6.72, 6.15, and $5.85{\log}_{10}CFU/g$, for organic perilla leaf, cabbage, and romaine lettuce, respectively. Major spoilage bacteria of organic and conventional fresh produces were similar however their levels were little different. For example, a major spoilage bacterium resulting the highest level on conventional perilla leaf was Stenotrophomonas maltophilia whereas that was Microbacterium sp. for organic produce. From these results, microflora or spoilage microorganism could be different depending on their cultivation types as conventional or organic produces and this information might be used for developing effective preservation method for different types of fresh produce.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1091-1097
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• 2002

In order to improve palatability and quality of traditional kochujang, kiwifruit (Actinidia deliciosa) was added to traditional kochujang fermented for 3 months. Physicochemical and microbial characteristics were investigated during fermentation at $30^{\circ}C$. Moisture contents of all treated kochujangs increased with increasing amount of kiwifruit added during fermentation. pH of kiwifruit-added kochujang was lower than that of the control kochujang, whereas no significant differences in titratible acidity was observed among all treatments. Crude protein and salt contents of kiwifruit-added kochujang were lower than those of the control, whereas no difference in crude fat contents were found. Ethanol and amino-nitrogen contents of 6 and 9% kiwifruit-added kochujang were higher than those of the control. Fructose contents of kiwi-added kochujangs were higher than that of the control. Major organic acids of kochujang were in the order of malic acid > citric acid > succinic acid > acetic acid > lactic acid > oxalic acid. Succinic acid level increased significantly during fermentation and was higher in kiwifruit-added kochujang than in the control. Bacterial cell counts of all treatments were not different, and viable cell count of yeast was slightly higher in kiwifruit-added kochujang only at the initial fermentation period. Sensory evaluation revealed that the addition of 9% kiwifruit was the optimum condition for improving kochujang quality.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.777-786
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• 2003

An experiment was conducted to investigate the effects of supplementary Blended essential oil(CRINA$^{\circledR}$) on the performance, nutrient availability, fatty acid composition of leg muscle, small intestinal microflora and blood parameters in broiler chickens. One thousand unsexed day-old broiler chickens were assigned to five treatments : control(T1), 5ppm avilamycin(starter diet) & 5ppm flavomycin(grower diet) T2, 5ppm avilamycin(starter diet) & 50ppm CRINA$^{\circledR}$(grower diet) T3, 50ppm CRINA$^{\circledR}$(starter & grower diet) T4, 50ppm CRINA$^{\circledR}$+ 500ppm lactic acid$^{\circledR}$ (starter & grower diet) T5. Each treatment had four replications of 50 birds each. Growth performance was significantly improved by dietary supplements(T2-T5). There were no significant differences among treatment T2, T3, T4 and T5. Feed intake was not significantly different among treatments. Dietary supplementation of CRINA$^{\circledR}$(T3, T4, T5) resulted in significant(p〈0.05) improvement in feed/gain(F/G) during finishing period (4-5weeks). The birds fed CRINA$^{\circledR}$ supplemented diet(T4) showed significantly(p〈0.05) higher availability of crude fat, methionine and methionine + cystine than those fed antibiotics supplemented diet(T2). Mortality was not significantly affected by treatments. The colony forming unit(CFU) of E.coli in small intestinal content was significantly lower in antibiotics & CRINA$^{\circledR}$(T3) compared to CRINA$^{\circledR}$ treatment(T4)(P〈0.05). CFU of Cl. perfringens was low in CRINA$^{\circledR}$(T4) but not different significantly with other treatments. Serum triglyceride level of birds fed CRINA$^{\circledR}$ + lactic acid diet(T5) was significantly lower(p〈0.05) than those fed antibiotics supplemented diet(T2). Cholesterol level of the birds fed antibiotics(T2) or CRINA$^{\circledR}$ + lactic acid supplemented diet(T5) was significantly higher(p〈0.05) than other treatments. HDL level of birds fed control diet was significantly lower(p〈0.05) than that of others. The levels of serum IgG were not significantly different among treatments. Major fatty acids composition of leg muscle fat was significantly influenced by treatments. Control group showed significantly higher palmitic acid(C$_{16:0}$) and steraric acid(C$_{18:0}$) content than other treatments(p〈0.05). Content of oleic acid(C$_{18:1}$), however, was significantly lower in the control than others treatments. Content of linolenic acid(C$_{18:3}$) was significantly higher in CRINA$^{\circledR}$+ lactic acid(T5) than antibiotics & CRINA$^{\circledR}$(T3) treatments. Total saturated fatty acids content was higher and total unsaturated fatty acids were lower in the leg muscle fat of the control than that of other treatments. It is concluded that CRINA$^{\circledR}$ supplementation improved growth rate and F/G ratio in broilers. The combination of CRINA$^{\circledR}$ with either antibiotics or lactic acid did not show any additive or synergistic effects in broiler chickens .

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.2
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• pp.106-111
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• 2018

This study was conducted to investigate the relationship between changes of rumen microflora and bloat in Jersey cow. Jersey cows (control age: 42 months, control weight: 558kg; treatment age: 29 months, treatment weight 507kg) were fed on the basis of dairy feeding management at dairy science division in National Institute of Animal Science. The change of microbial population in rumen was analyzed by using next generation sequencing (NGS) technologies due to metabolic disease. The diversity of Ruminococcus bromii, Bifidobacterium pseudolongum, Bifidobacterium merycicum and Butyrivibrio fibrisolvens known as major starch fermenting bacteria was increased more than 36-fold in bloated Jersey, while cellulolytic bacteria community such as Fibrobacter succinogenes, Ruminococcus albus and Ruminococcus flavefaciens was increased more than 12-fold in non-bloated Jersey. The proportion of bacteroidetes and firmicutes was 33.4% and 39.6% in non-bloated Jersey's rumen, while bacteroidetes and firmicutes were 24.9% and 55.1% in bloated Jersey's. In conclusion, the change of rumen microbial community, in particular the increase in starch fermenting bacteria, might have an effect to occur the bloat in Jersey cow.

• Applied Biological Chemistry
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• v.33 no.4
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• pp.330-336
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• 1990

In order to Process rapid fermented anchovy with low salt contents, processing condition of rapid fermented anchovy by proteolytic bacteria, and its chemical composition and quality stability during storage were examined. Culture was performed(pH 7.0, $40^{\circ}C$, 45strokes/min) for 15hrs after the addition of 1% of NaCl, 1% of sodium erythorbate and 20m1 of B. licheniformis p-5 cultures($3.2{\times}10^4cells/ml$) to 100g of raw anchovy, and then low salt fermented anchovy as final product was made by adding of several(3% of NaCl, 4% of KCI, 4% of ethyl alcohol(w/v), 0.5% of ginger, 0.5% of garlic powder) for stability and flavor enhancement. During 60days of storage, histamine contents was adequate in a food sanitation aspect, and microflora decreased sharply while volatile basic nitrogen increased slowly. Free amino acids are the major part in unique fermented anchovy taste. The volatile fatty acids is the most important component in the anchovy's flavor. From the results of experiments, it was supposed that rapid fermented anchovy processed with proteolytic bacteria was suitable.

• Culinary science and hospitality research
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• v.15 no.2
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• pp.298-308
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• 2009

In order to establish the quality standard of Jeju traditional Doenjang(soybean paste), general components, free sugar, organic acid, fatty acids, amino acids, and isoflavones contents were analyzed. Moisture, crude ash, crude protein, crude lipid, acid value, pH, and salinity were 37.33~47.43%, 12.75~15.97%, 11.06~14.28%, 0.08~0.53%, 17.83~27.55 mg/g, 4.82~5.12, and 10.66~13.91% respectively. The content of amino type nitrogen was 301.06~573.89 mg%. The compositions of free sugar were glucose (0.81~10.22 mg/g), maltose(0.64~5.28 mg/g), sucrose(0.78~3.86 mg/g), and fructose(0.72~1.11 mg/g). The major organic acid was lactic acid (89.30~180.39 mg/g). Total free amino acids were from 13.89 to 15.51%, which makes no difference between the test samples. Among amino acids, glutamic acid was abundant (2.12~2.55%). The contents of isoflavones were 274.87~431.96 mg/kg, less than those of commercial soybean paste. In fatty acid composition of soybean paste, the most abundant fatty acid was found to be linoleic acid as 61.54~66.79% in Jeju traditional Doenjang. This results might be caused by the differences of brewed periods, microflora, processing methods and used soybean cultivars.

• Microbiology and Biotechnology Letters
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• v.11 no.1
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• pp.53-58
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• 1983

Sik-hae is a traditional Korean fermented fish product which is made from flat-fish, garlic, salt, red pepper and millet. The changes in chemical composition, pH, acidity and the contents of Amino-N, VBN, TMA and organic acids were investigated during the fermentation of Sik-hae. The changes in the microflora, enzyme activity and the sensory quality including textural characteristics were also evaluated. The changes in the contents of crude protein, crude fat and moisture during Sik-hae fermentation were negligible. The pH of the product tended to decrease in the course of fermentation and it showed the minimum value of 4.5 after 7 days of fermentation. On the other hand the acidity continued to increase up to 2300mg % by 4 weeks of fermentation. Lactic acid was the major organic acid. The content of Amino-N in sik-hae gradually increased up to 673.6mg % by 2 weeks of fermentation, and then slightly decreased. The content of VBN increased rapidly during the first 2 weeks of fermentation, while little changes in TMA content was observed. The number of proteolytic bacteria increased slightly for the first 2 weeks and then rapidly decreased. The number of yeast and acid forming bacteria increased rapidly from the 4th day to the 14th day of fermentation and then decreased. Both lipase and protease activities showed the maximum at the 11th day of fermentation. The texture softening of the fish occurred after 1 week of fermentation and the adhesiveness appeared after 2 weeks of fermentation. Summarizing these results, the optimum fermentation time for Sik-hae from flat fish were 2 weeks at 2$0^{\circ}C$ and the quality of the product could be kept for up to 4 weeks in refrigerator.

• Journal of Microbiology and Biotechnology
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• v.27 no.8
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• pp.1392-1400
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• 2017

Galactooligosaccharides (GOSs) are known to be selectively utilized by Bifidobacterium, which can bring about healthy changes of the composition of intestinal microflora. In this study, ${\beta}-GOS$ were synthesized using bifidobacterial ${\beta}-galactosidase$ (G1) purified from recombinant E. coli with a high GOS yield and with high productivity and enhanced bifidogenic activity. The purified recombinant G1 showed maximum production of ${\beta}-GOSs$ at pH 8.5 and $45^{\circ}C$. A matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of the major peaks of the produced ${\beta}-GOSs$ showed MW of 527 and 689, indicating the synthesis of ${\beta}-GOSs$ at degrees of polymerization (DP) of 3 and DP4, respectively. The trisaccharides were identified as ${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-glucopyranose, and the tetrasaccharides were identified as ${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-($1{\rightarrow}4$)-O-${\beta}-{\text\tiny{D}}$-glucopyranose. The maximal production yield of GOSs was as high as 25.3% (w/v) using purified recombinant ${\beta}-galactosidase$ and 36% (w/v) of lactose as a substrate at pH 8.5 and $45^{\circ}C$. After 140 min of the reaction under this condition, 268.3 g/l of GOSs was obtained. With regard to the prebiotic effect, all of the tested Bifidobacterium except for B. breve grew well in BHI medium containing ${\beta}-GOS$ as a sole carbon source, whereas lactobacilli and Streptococcus thermophilus scarcely grew in the same medium. Only Bacteroides fragilis, Clostridium ramosum, and Enterobacter cloacae among the 17 pathogens tested grew in BHI medium containing ${\beta}-GOS$ as a sole carbon source; the remaining pathogens did not grow in the same medium. Consequently, the ${\beta}-GOS$ are expected to contribute to the beneficial change of intestinal microbial flora.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.1
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• pp.1-9
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• 2013

Long term hydrogen production was investigated in an anaerobic sequencing batch reactor (ASBR) using mixed microflora. Glucose (about 8,250 mg/L) was used as a substrate for the ASBR operation under the condition of pH 5.5 and $37^{\circ}C$ with mixing at 150 rpm. The experiment was carried out over a period of 160 days. Hydrogen yield was 0.8mol $H_2/mol$ glucose with F/M ratio 2 at initial operation period. The hydrogen yield reached to maximum 2.6 mol $H_2/mol$ glucose at 80th day operation. However decreased hydrogen yield was observed after 80 days operation and eventually no hydrogen yield. Although well-known hydrogen producer Clostridium sp. was detected in the reactor by PCR-DGGE analysis, changed reactor operation was the major reason of the decreased hydrogen production, such as low F/M ratio of 0.5 and high propionic acid concentration 2,130 mg/L. Consequently the long period operation resulted in MLSS accumulation and then low F/M ration stimulating propionic acid formation which consumes hydrogen produced in the reactor.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.666-672
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• 2002

Changes in chemical characteristic, microflora, and sensory evaluation of fish sauce extracted at an interval of one week from fermented solution were investigated. pH was reduced from 6.0 to 4.5, and trimethylamine oxide from 132.5 to 87.2 mg/100g during fermenting periods. Trimethylamine increased from 5.6 to 50.2 mg/100g, and volatile basic nitrogen from 48.3 to 232.5 mg/100g. Bacterial flora isolated from the fish sauce were 70% Lactobacillus sp. and 13% Bacillus sp. Among the free amino acids, alanine, glutamic acid, valine, and methionine contents constitute 40% of the total free amino acids. Major non-volatile organic acid of the fish sauce was lactic acid (76%). Sensory evaluation results of the fish sauce were higher than the traditional soybean sauce after 28 days of fermentation.