• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.8
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• pp.1227-1232
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• 2016

Electrolyzed activated water (EAW) has been reported to exhibit strong bactericidal effects on foodborne microorganisms. However, the disinfection efficacy of EAW is affected by factors such as water source and hardness. This study investigated bactericidal effects of EAW against three gram-positive (Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus) and three gram-negative (Cronobacter sakazakii, Escherichia coli O157:H7, and Salmonella Enteritidis) foodborne pathogens. Six strains were treated with EAW prepared at different water temperatures (4, 22, and $40^{\circ}C$) for 15 min, and D-values were generated. The results show that the lowest D-values for Lis. monocytogenes by EAW produced at $4^{\circ}C$ and $40^{\circ}C$ were 6.60 and 1.57 min, respectively. The lowest D-value for Sal. Enteritidis by EAW produced at $22^{\circ}C$ was 2.92 min. D-values of all strains treated by EAW produced at $40^{\circ}C$ decreased significantly compared to those treated by EAW produced at $4^{\circ}C$ (P<0.05). These results demonstrate that applying EAW produced at warm temperature is more effective for reducing foodborne pathogens for food safety.

• Journal of Life Science
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• v.22 no.2
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• pp.251-258
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• 2012

The purpose of this study was to investigate the probiotic properties of lactic acid bacterial strains isolated from animal feces. BCNU 9041 and BCNU 9042 isolates were assigned to Lactobacillus brevis on the basis of their physiological properties and 16S ribosomal DNA sequences analysis. They were confirmed as safe bioresources because of their non-hemolytic activities and non-production of harmful ${\beta}$-glucosidase, ${\beta}$-glucuronidase, tryptophanase, or urease. These isolates were also highly resistant to acid (at pH 2.5) and bile acids (at concentration of 0.3%, 0.6%, and 1% oxgall). In addition, they exhibited good antibacterial activity against food-borne bacteria, especially Bacillus cereus, Listeria monocytogenes, and Shigella sonnei. Furthermore, it was demonstrated that they have the highest levels of hydrophobicity and that they showed bile salt hydrolytic and cholesterol assimilation activity. These results suggest that BCNU 9041 and 9042 have good potential for application in functional foods and health-related products.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.5
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• pp.487-494
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• 2004

The effect of water extracts of Chungkukjang(WEC: 10%, w/v), which was prepared using Bacillus subtilis isolated from Korean traditional Chungkukjang, on the pH, acidity and volume of the dough, and loaf volume index(LVI), color, texture, retrogradation degree, microscopic observation and sensory quality of the bread were investigated. Experimental plots were divided to 3 groups(Control; without WEC, I; added 2.5% WEC against total amount of water, II; added 5.0% WEC against total amount of water). There were no significant difference in pH and acidity among each experimental groups. Dough volume were higher but LVI were lower in the 1- and II-bread than those of control group. L* values of the top crust and internal tissue in the I- and II-bread were lower than those of control group. The higher addition amounts had the lower L* values. Hardness, strength, gumminess and brittleness were higher, but cohesiveness and springiness were lower in the WEC-breads than those of control. In the results of microscopic observation, there were scarce of the bigger starch granules and a sparse structure, while there were smaller starch granules in the WEC-bread. The scores of crispy taste of the WEC-bread were lower than those of the control group, but there were no significant difference in tenderness, odor, savory taste and overall acceptability between the control and the I-bread. The retrogradation rate of the bread stored for 3 days at 25℃ was 45.09% in control, 17.92% in I-bread, and 12.45% in II-bread, respectively.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.204.2-205
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• 1978

발효유 원료유중에 항생물질이 함유되어있을 경우 이것이 발효유 제조에 미치는 영향을 검토하였다. 발효유의 원가유 살균과정, 배양기간, 보존기간중에 있어서 항생물질의 변화를 검토하기 위하여 Bacillus stearothermophilus var. calidolactis C 953을 사용한 cylinder plate법으로 penicillin의 역가를 측정하였다. 저온 장시간 $살균(60^{\circ}C,$ 30분) 조건에서는 조금도 불활성화되지 않았으나, 온도를 높이고, 시간을 길게함에 따라 점점 불활화률이 높아져 $고압멸균조건(121^{\circ}C,$ 15분)에서는 약 90% 이상이 불활화되었다. 또 현재 우리나라에서 발효유제조에 사용되고 있는 Lactobacillus casei, Hy3와 Lactoba-cillus bulgaricus Hy4A, Hy4B를 사용하여 $37^{\circ}C에서$ 배양할 경우 배양기간 중에 있어서 penicillin은 2일내에 95% 이상 불활화되었다. 그리고 $보존기간(5^{\circ}C)$ 중에는 phosphate buffer(pH 6.0)와 10% skim milk의 경우에 10일까지도 거의 불활화가 되지 않았으나, 발효유내에서는 5일만에 85% 이상이 불활화된다는 결과를 얻었다. 이와같은 발효유 배양기간과 보존기간 중의 penicillin 불활화의 원인을 규명하기 위하여 각종 유기산의 영향을 조사한 결과(조건 pH.3.30~3.45, 보존온도 $37^{\circ}C),$ 염산과 유산의 경우 24시간, 구연산의 경우 48시간, 초산의 경우 72시간내에 실험에 사용한 penicillin 농도의 99.99%가 불활화되었다. 이러한 결과로 볼 때 유산발효에서 penicillin이 불활화되는 주원인은 발효에 의하여 생성된 유기산에 의한 것으로 추정된다.방식이군이 중지방식이군과 고지방식이군에 비해 혈장내 LCAT 활성이 유의하게9p<0.001) 증가하였다. 3) 간의 콜레스테롤합성 능력은 정어리유군이 다른지방군보다(p<0.001), 무지방식이군이 식이지방첨가군보다(p<0.001), 동물성지방군의 식물성유지군보다 유의하게(p<0.001) 증가하였으나, 식이 지방의 수준에 의한 차이는 나타나지 않았다. 수용성 식이섬유소가 생리져 기능이 거의 비슷하고 무독성이 관찰됨으로써 신갈나무로부터 제조된 수용성 식이섬유소의 제조 방법이 우수하다고 볼 수 있다.있었다.세에 해당되는 중년 여성의 에너지, 단백질, 철분 섭취량을 권장량과 비교하여 보면, 각각 74.8$\pm$12.6%, 94.6$\pm$26.4% 및 64.5$\pm$14.1%로 당뇨군 (각각 112.8$\pm$28.5%, 157.8$\pm$68.2%, 92.8$\pm$21.7%)에 비해 유의하게 낮았고 정상군과는 유의한 차이를 보이지 않았다.상고나성이 있었다. 혈중 호모시스테인 농도는 질병의 위험요인으로서 뿐 아니라 대사적으로 밀접하게 연관된 비타민 영양상태의 biomarker로서도 그 영향력이 크다고 할 수 있다. 따라서 성별에 다른 다양한 연령집단에서 건강한 일반인과 심혈관계 질환자 등을 대상으로 호모시스테인과 비타민 영양상태에 대한 연구가 체계적으로 이루어 져야 할 것이다.태를 보다 효율적으로 증진시킬 수 있는 대안이 마련되어져야 한다고 사료된다.$\ulcorner$순응$\lrcorner$의 범위를 벗어나지 않는다. 그렇기 때문에도 $\ulcorner$순응$\lrcorner$과 $\ulcorner$표현$\lrcorner$의 성격과 형태를 외형상으로 더욱이 공간상에서는

• Journal of Life Science
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• v.27 no.2
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• pp.131-138
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• 2017

In this study, for the efficient use of the byproduct of the omija (Schizandra chinensis Baillon: SC) processing industry, the ethanol extracts of the fruit (F), seed (S), and pomace (P) of SC were prepared, and their useful bioactivities were evaluated. For F-SC, S-SC, and P-SC, the extraction yields were 28.3%, 22.1%, and 7.2%, respectively, and the polyphenol contents were 8.81, 37.22, and 9.20 mg/g, respectively. The total flavonoid content in P-SC (4.31 mg/g) was 3.5-fold higher than that in F-SC (0.76 mg/g). In an antioxidation activity assay, P-SC showed stronger radical scavenging activities against DPPH anion, ABTS cation, and nitrite and stronger reducing power activities than the other extracts. The calculated concentration required for 50% radical scavenging activity, $RC_{50}s$, of P-SC for DPPH anion, ABTS cation, and nitrite was 226.2, 192.5, and $92.5{\mu}g/ml$, respectively. In an antimicrobial activity assay, F-SC, S-SC, and P-SC showed similarly strong growth inhibitions against Bacillus subtilis and P. vulgaris at a concentration of 0.5 mg/disc. F-SC and P-SC showed 15-fold extended time in thrombin, prothrombin, and activated partial thromboplastin time assays at a concentration of 5 mg/ml. The anticoagulation activity of P-SC (2.5 mg/ml) was comparable to that of aspirin (1.5 mg/ml). Furthermore, F-SC and S-SC showed very good platelet aggregation inhibitory activities. F-SC, S-SC, and P-SC did not show significant hemolysis against human red blood cell up to a concentration of 0.5 mg/ml. These results suggest that S-SC and P-SC, both of which are byproducts of the omija processing industry, show strong potential as novel antioxidant, antimicrobial, and antithrombosis agents.

• Journal of Microbiology and Biotechnology
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• v.23 no.11
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• pp.1617-1626
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• 2013

The Bacterial community structure and its complexity of the enrichment culture during the isolation and screening of imidacloprid-degrading strain were studied using denaturating gradient gel electrophoresis analysis. The dominant bacteria in the original tea rhizosphere soil were uncultured bacteria, Rhizobium sp., Sinorhizobium, Ochrobactrum sp., Alcaligenes, Bacillus sp., Bacterium, Klebsiella sp., and Ensifer adhaerens. The bacterial community structure was altered extensively and its complexity reduced during the enrichment process, and four culturable bacteria, Ochrobactrum sp., Rhizobium sp., Geobacillus stearothermophilus, and Alcaligenes faecalis, remained in the final enrichment. Only one indigenous strain, BCL-1, with imidacloprid-degrading potential, was isolated from the sixth enrichment culture. This isolate was a gram-negative rod-shaped bacterium and identified as the genus Ochrobactrum based on its morphological, physiological, and biochemical properties and its 16S rRNA gene sequence. The degradation test showed that approximately 67.67% of the imidacloprid (50 mg/l) was degraded within 48 h by strain BCL-1. The optimum conditions for degradation were a pH of 8 and $30^{\circ}C$. The simulation of imidacloprid bioremediation by strain BCL-1 in soil demonstrated that the best performance in situ (tea soil) resulted in the degradation of 92.44% of the imidacloprid (100 mg/g) within 20 days, which was better than those observed in the ex situ simulations that were 64.66% (cabbage soil), 41.15% (potato soil), and 54.15% (tomato soil).

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.9
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• pp.1487-1496
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• 2020

Objective: The objective of this study was to look for optimal preparation of hydrolysates of desalted duck egg white powder (DDEWP) by the three different proteases and to investigate their antioxidant and antimicrobial properties. Methods: DDEWP was hydrolyzed by three proteases, including pepsin (PEP), Bacillus spp. (BA) and natokinase (NAT) with three different enzyme concentrations (0.1%, 0.3%, and 0.5%), individually. The important key hydrolysis parameters such as hydrolysis degree, yield, antioxidant and antimicrobial activity were evaluated in this experiment. Results: The results showed that the degree of hydrolysis (DH) of all treatments increased with increasing hydrolysis time and protease concentrations. The antioxidant and antimicrobial activities of the hydrolysates were affected by type and concentration of protease as well as hydrolysis time. Hydrolysis of PEP significantly (p<0.05) obtained the highest yield of hydrolysates, however, both of BA and NAT showed substantially lower DH values and still did not exceed 5% by the end of hydrolysis. Among the different hydrolysates, PEP exhibited significantly higher 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity than BA and NAT. All DDEWP hydrolysates from PEP had low ferrous ion chelating activity (<37%) that was significantly lower than that of NAT (>37% to 92%) and BA (30% to 79%). Besides, DDEWP hydrolysates of PEP presented significantly higher reducing power than BA and NAT. In antimicrobial activities, Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa were not effectively inhibited by any DDEWP hydrolysates of PEP except for Staphylococcus aureus. Especially, the excellent antibacterial activity against S. aureus only was displayed in DDEWP hydrolysates of PEP 0.1%. Conclusion: DDEWP hydrolysates from PEP demonstrated significantly better DH, yield, DPPH radical scavenging activity and reducing power, furthermore, had excellent inhibitory on S. aureus due to large clear zone and moderated inhibitory in bactericidal inhibition.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.10
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• pp.1490-1499
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• 2016

In this study, 69 lactobacilli isolated from Tibetan Qula, a raw yak milk cheese, were screened for their potential use as probiotics. The isolates were tested in terms of: Their ability to survive at pH 2.0, pH 3.0, and in the presence of 0.3% bile salts; tolerance of simulated gastric and intestinal juices; antimicrobial activity; sensitivity against 11 specific antibiotics; and their cell surface hydrophobicity. The results show that out of the 69 strains, 29 strains (42%) had survival rates above 90% after 2 h of incubation at pH values of 2.0 or 3.0. Of these 29 strains, 21 strains showed a tolerance for 0.3% bile salt. Incubation of these 21 isolates in simulated gastrointestinal fluid for 3 h revealed survival rates above 90%; the survival rate for 20 of these isolates remained above 90% after 4 h of incubation in simulated intestinal fluid. The viable counts of bacteria after incubation in simulated gastric fluid for 3 h and simulated intestinal fluid for 4 h were both significantly different compared with the counts at 0 h (p<0.001). Further screening performed on the above 20 isolates indicated that all 20 lactobacilli strains exhibited inhibitory activity against Micrococcus luteus ATCC 4698, Bacillus subtilis ATCC 6633, Listeria monocytogenes ATCC 19115, and Salmonella enterica ATCC 43971. Moreover, all of the strains were resistant to vancomycin and streptomycin. Of the 20 strains, three were resistant to all 11 elected antibiotics (ciprofloxacin, erythromycin, tetracycline, penicillin G, ampicillin, streptomycin, polymyxin B, vancomycin, chloramphenicol, rifampicin, and gentamicin) in this study, and five were sensitive to more than half of the antibiotics. Additionally, the cell surface hydrophobicity of seven of the 20 lactobacilli strains was above 70%, including strains Lactobacillus casei 1,133 (92%), Lactobacillus plantarum 1086-1 (82%), Lactobacillus casei 1089 (81%), Lactobacillus casei 1138 (79%), Lactobacillus buchneri 1059 (78%), Lactobacillus plantarum 1141 (75%), and Lactobacillus plantarum 1197 (71%). Together, these results suggest that these seven strains are good probiotic candidates, and that tolerance against bile acid, simulated gastric and intestinal juices, antimicrobial activity, antibiotic resistance, and cell surface hydrophobicity could be adopted for preliminary screening of potentially probiotic lactobacilli.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.10
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• pp.1235-1240
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• 2007

For this study, plant material for development of phytobiotics (feed additives made with plant extract) was screened. Among hot-water extracts of 9 medicinal plants, Fallopia japonin showed the highest antioxidative activity; the electron donating ability (EDA) and nitrite scavenging ability were 86.9% and 92.7%, respectively. Also, F. japonica had the antimicrobial activity for Pseudomonas aeruginora, Escherichia coli, Bacillus cereus, Salmonella Typhimurium, Listeria monocytogenes, Klebsiella pneumoniae, Staphyzococcus aureus. Specially, antimicrobial activity of F. japonica against K. pneumoniae, and S. aureus was vet strong. $IC_{50}$ of F. japonica against K. pneumoniae, and S. aureus was 6.24 mg/mL and 1.8 mg/mL respectively. These results suggested that F. japonica was a candidate for a phytobiotic material.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.2
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• pp.140-145
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• 2000

This study was performed to investigate whether the earthworm cast could be reused as bulking agent in the whole processing of the food wastes using the earthworm. In addition, the growth conditions of microorganism lived upon earthworm lasts was investigated. Because the raw food wastes used in this experiment had low pH, and high moisture and organic matter contents, it was unsuitable to use as direct feeds to earthworm. However, when the food wastes were mixed with some earthworm cast, the mixtures were suitable to the feed condition and the growth environment of the earthworm. Therefore, it shows the possibility that the earthworm cast be reused as bulking agent for food wastes. In the microbiological investigation on earthworm cast, the bacteria showed most high density among the microbial species. And the microbial density showed higher under the mid-temperature than under high-temperature, and higher under the anaerobic than the aerobic condition. The drying methods of earthworm cast for the moisture adjusting, has no effect on microorganism growth whether natural or artificial drying. And the activity of enzyme presented more highly before the drying than after the drying.