• 한국물환경학회지
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• 제20권5호
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• pp.480-487
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• 2004

This study was conducted to find the effect of electron acceptors on the formation of granular sludge by using four different types of electron acceptors. The phosphorous uptake, denitrification, and sulfate reduction in anoxic modes were simultaneously occured because of the presence of the polyphosphate accumultating organism(PAO) that utilize nitrate and sulfate as an electron acceptor in the anoxic zone. Denitrirying phosphorous removal bacteria(DPB) was enriched under anaerobic/anoxic/aerobic condition with a nitrate as an electron acceptor, and desulfating phosphorous removal bacteria(DSPB) was enriched under anaerobic/anoxic/aerobic condition with a sulfate as an electron acceptor. Polyphosphate accumulating organism(PAO) were enriched in the anaerobic/aerobic SBR. PAO took up acetate faster than DPB and DSPB during the aerobic phase. The sludge with nitrate and sulfate as an electron acceptors grew as a granules which possessed high activity and good settleability. In the anaerobic/aerobic modes, typical floccular growth was observed. In the result of bench-scale experiment, simultaneous reactions of phosphorus uptake, denitrification and sulfate reduction were observed under anoxic condition with nitrate and sulfate as an electron acceptors. These results demonstrated that the anaerobic/anoxic modes with nitrate and sulfate as an electron acceptors played an important role in the formation of the sludge granulation.

• 한국조리학회지
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• 제6권3호
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• pp.357-371
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• 2000

Changes of Microflora, enzyme activity, and contents of several taste compounds in traditional Kanjang(Korean Soy Sauce) with the variation of fermentation jars and Meju(fermented soybean brick)concentration were studied. Substitution possibilities of clay jar with glass jar and improvement possibilities of taste and nutritional value with increased Meju concentration were examined. (1) Aerobic bacteria and lactic acid bacteria were enumerated during fermentation and ripening period. But yeast and molds were hardly isolated. The number of viable cells showed small changes during fermentation and ripening period. (2) Isolated Aerobic bacteria were identified as Bacillus subtilis, Bacillus lichenformis, and lactic acid bacteria were identified as Lactlbacillus lactis lactis and lactobacillus brevis. (3) The activities of $\alpha$-amylase and $\beta$-amylase increased during fermentation period, but did not show any trend by fermentation jars or Meju concentrations. Protense activity showed small difference among four samples, and increased during the fermentation period.

• 미생물학회지
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• 제30권6호
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• pp.495-500
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• 1992

Photosynthetic bacteria which can utilize ferulate as a sole carbon source for their metabolic activities were isolated from soils by liquid enrichment culture technique. The strain P-1 was selected by the highest capability of degrading ferulate in aerobic and anaerobic conditions. The strain P-1 was rod-shaped with its motility, strained gram negatively and could not utilize sulfur compounds. This strain has the bacteriochlorophyll a group I carotenoid and membrane structures like lamellae. As the results of physiological, morphological and cultural charactderistics, the isolate was identified as Rhodopseudomonas plaustris, one of the purple nonsulfer bacteria. The strain P-1 utilized 2mM/day in aerobic condition and 0.86 mM/day in anaerobic condition.

• 산업기술연구
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• 제31권B호
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• pp.113-117
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• 2011

The purpose of this study is to determine the antimicrobial effect of tea tree oil a against pathogens relate to acne. Tea tree oil extracted from Australian Melaleuca alterifolia has been studied extensively for their antimicrobial properties against different type of bacteria and fungi. Tea tree oil has been reported to have antibacterial, antiinflammatory and antitumor activities, among others. By evaluating the antibacterial effect of Tea Tree Oil of Australia, the MIC value of Tea Tree oil against P. acnes was 0.05% and 0.5% against aerobic bacteria. This study showed that Tea Tree Oil has antibacterial effect against bacteria which induce acne. Tea Tree Oil had better antibacterial effect against P. acnes compared to aerobic bacteria. It is promising to develop a nature-based functional material for makeup product, which can cure and prevent acne.

• 한국식품위생안전성학회지
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• 제24권4호
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• pp.348-351
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• 2009

본 연구는 생면산업 현장에서 주로 사용하고 있는 주정(ethanol)의 첨가에 따른 미생물의 증식변화와 유통기한 연장 효과를 과학적으로 평가해보고자 하였다. 이를 위해 ethanol을 0, 1, 2% 첨가하였으며, $10^{\circ}C$ 에서 저장하는 동안에 생면의 총균수의 변화를 측정하였다. 생면의 품질 기준인 6 log cfu/g을 적용하여 유통기한을 추산하였다. 그 결과 ethanol 첨가 생면의 유통 가능기한은 무첨가군의 경우 9.17일, 1% 첨가군의 경우 15.02일, 2% 첨가군의 경우 27.03일로 추정되어 무첨가군과 비교하여 63.8%, 194.8%의 유통기한을 연장효과를 보였다. 따라서, 생면에 주정(ethanol)의 첨가는 유통기한 연장에 효과적인 것으로 평가되었다.

• 한국토양비료학회지
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• 제44권6호
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• pp.1181-1184
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• 2011

Total aerobic bacteria, Esherichia coli O157:H7, and Salmonella spp. were examined in commercial liquid pig manures. Commercial liquid pig manures (n=33) were collected from muck joint resource recovery plant at April, June, August, October 2009, Korea. Total aerobic bacteria were incubated at $37^{\circ}C$ for 24-48 hrs, and quantified as a colony-forming unit (CFU) $mL^{-1}$. Analysis of Esherichia coli O157:H7 and Salmonella spp. were followed by Korean Food Standards Codex method. Colony of Salmonella spp. was confirmed by API kit and real time polymerase chain reaction (PCR). Total aerobic bacteria isolated from fermented commercial liquid pig manures ranged from 2.8 to $24.3{\times}10^4\;CFU\;mL^{-1}$. Esherichia coli O157:H7 was not detected, and Salmonella spp. showed the low detection frequency at only 1 sample. This study suggests that continuous monitoring in commercial liquid pig manures is required to improve the agricultural food through management of agricultural land contaminated with liquid pig manures.

• 산업식품공학
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• 제22권4호
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• pp.321-327
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• 2018

19종의 과채류에 대한 동결점 및 빙핵 형성 온도, 함수율, 경도, 당도, pH를 측정하여 Pearson 상관분석을 하였다. 동결점은 함수율과 당도에 p<0.01의 유의적인 상관관계를 나타냈으나, 빙핵 형성 온도는 당도에만 p<0.05의 상관관계를 보였다. 특히 동결점과 빙핵 형성 온도의 차이값인 과냉각 격차 FSD와는 함수율과 당도 등이 모두 상관관계를 보이지 않았다. 호기성세균, 유산균, 효모, 곰팡이의 다양한 미생물이 분포하는 배추에 대한 미생물 분석과 FSD와의 상관분석을 수행하였는데, 호기성 세균과 p<0.01의 상관관계가 나타났다. 호기성 세균을 9.4 log CFU/mL의 농도로 접종한 식염수와 이를 멸균한 시료를 각각 $10^2$, $10^4$, $10^6$ 배로 희석하여 동결점과 빙핵 형성 온도 분석에서도 높은 농도의 호기성 세균이 빙핵 형성 온도를 높이는 결과가 나왔다. 하지만, 약 5 log CFU/mL 수준 이하에서는 멸균식염수와 빙핵 형성 온도의 통계적 차이가 없는 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제28권4호
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• pp.502-510
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• 2015

The objective of this study was to assess the use of peach pomace in total mixed ration (TMR) silages and clarify the differences in aerobic stability between TMR and TMR silages caused by lactic acid bacteria (LAB). The TMR were prepared using peach pomace, alfalfa hay or Leymus chinensis hay, maize meal, soybean meal, cotton meal, limestone, a vitamin-mineral supplement, and salt in a ratio of 6.0:34.0:44.4:7.0:5.0:2.5:1.0:0.1 on a dry matter (DM) basis. Fermentation quality, microbial composition, and the predominant LAB were examined during ensiling and aerobic deterioration. The results indicated that the TMR silages with peach pomace were well fermented, with low pH and high lactic acid concentrations. The aerobic stability of TMR silages were significantly higher than that of TMR. Compared with TMR silages with alfalfa hay, TMR silage with Leymus chinensis hay was much more prone to deterioration. Although the dominant LAB were not identical in TMR, the same dominant species, Lactobacillus buchneri and Pediococcus acidilactici, were found in both types of TMR silages after 56 d of ensiling, and they may play an important role in the aerobic stability of TMR silages.

• Fisheries and Aquatic Sciences
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• 제22권11호
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• pp.26.1-26.7
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• 2019

Background: The monitoring of pathogens of fishery auction markets is important to obtain safe fishery products regarding hygiene and sanitation. In this study, aerobic, coliform, Escherichia coli, and Vibrio cholerae were monitored in the fishery products and environmental samples obtained from fishery auction markets. Methods: The fishery products (flounder, octopus, skate, rock cod, sea bass, snail, monkfish, flatfish, comb pen shell, corb shell, conger eel, hairtail, croaker, and pilchard) were placed in filter bags, and the environmental samples (samples from the water tanks at the fishery auction markets, seawater from the fishery distribution vehicles, ice from wooden or plastic boxes, and surface samples from wooden and plastic boxes used for fish storage) were collected. Aerobic bacteria, E. coli, and coliform in the samples were enumerated on aerobic count plates and E. coli/coliform count plates, respectively. For V. cholerae O1 and V. cholerae non-O1 quantification, most probable number (MPN)-PCR analysis was performed. Results: Aerobic and coliform bacteria were detected in most samples, but E. coli was not detected. Wooden boxes were contaminated with high levels of aerobic and coliform bacteria in all seasons (spring, summer, and fall). During fall, V. cholerae non-O1 were detected in snails, hairtails, croakers, flatfishes, pilchards, plastic boxes, and water samples. Conclusions: These results indicate an increased prevalence of V. cholerae contamination in fishery products in fall, including food contact samples, which can be vehicles for cross-contamination.

• 한국수산과학회지
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• 제54권6호
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• pp.1045-1051
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• 2021

Eighty-nine different types of commercially salt-fermented fishery products comprising various raw materials were analyzed for total aerobic bacteria, number of coliform bacteria, fecal coliform, and Escherichia coli. The food-poisoning bacterial content of the samples was investigated using next-generation sequencing. The mean mass of total aerobic bacteria in Jeotgal was 6-1.8×10⁹ CFU/g, and that in Aekjeot and Sikhae was 4-2.2×10⁵ CFU/mL and 1.9×10⁵-8.4×10⁸ CFU/g, respectively. Coliform bacteria were detected in 9 (28.1%) of 32 Jeotgal samples; 15 (46.8%) of 32 seasonal Jeotgal samples; and in 5 (55.5%) of 9 Sikhae samples. Fecal coliform and E. coli were not detected in 86 of the 89 samples. Yersinia enterocolitica was detected only in Galchi jeot (salt-fermented hairtail) (1 type) and not in other Jeotgal samples. These results contribute to our knowledge regarding the bacterial stability of salt-fermented fishery products.