• 한국환경보건학회지
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• 제33권6호
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• pp.493-496
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• 2007

The influences of contact time and ratio of food to microorganism (F/M) on uptake of wastewater organic matter in a short contact process were investigated using three activated sludge batch reactors fed with synthetic wastewater, sewage and livestock wastewater. About 64% of influent soluble chemical oxygen demand (SCOD) in the synthetic wastewater and 61% of SCOD in the sewage and 43% of SCOD in the diluted livestock wastewater were adsorbed into the activated sludge within 30 min. The specific mass of organic matter uptaken in the synthetic wastewater was 55 mg SCOD/g mixed liquor suspended solids (MLSS). In the same manner, 20 and 14 mg SCOD/g MLSS were calculated as the values in the sewage and livestock wastewater, respectively.

• 한국환경보건학회지
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• 제28권5호
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• pp.22-27
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• 2002

The composting practice has been recognized as the most popular way of controlling food waste and many attempt have been made in the field to establish more efficient and economical process. Some of the efforts are mixing cured compost with sawdust as alternative bulking agent, seeding commercially produced microorganism and/or combination of above. However, verification of such efforts is often restricted because of either the lack of engineering consideration on the limitation of composting facility scales. In this study, the effect of mixing materials in food waste composting was investigated by controlling the combination and the mixing ratio of them. When the cured compost was mixed with saw dust. the decomposition of organic material was proven to be more active by observing the compost temperature, the oxygen (O$_2$) consumption, and the cumulative carbon dioxide ($CO_2$) profile. However, the quantity of compost mix-ing seemed not to influence the reaction as long as the minimum required amount was mixed. The feeding of com-mercially produced microorganism had a tendency to prolong the thermophilic stage, which helped to increase the decomposition but it resulted in composting period. Regardless of the composting condition, bacteria and actinomycetes increased in population as the reaction approached to the end. The population of bacteria and actinomycetes were rel-atively higher than those of fungi and yeast throughout the reaction.

• Asian-Australasian Journal of Animal Sciences
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• 제15권4호
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• pp.596-601
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• 2002

The present study was designed to examine the effect of ozone treatment in microencapsulated ${\beta}$-galactosidase on inactivation of the enzyme and sterilization of microorganism. The efficiency was the highest as 78.4% when the ratio of polyglycerol monostearate (PGMS) was 15:1. Activities of lactase remaining outside the capsule were affected by ozone treatment. With the increase of ozone concentration and duration of ozone treatment, the activity reduced significantly. In sensory aspect, with 2% microcapsule addition, no significant difference in sweetness was found compared with a market milk during 12 d storage. Above result indicated that the additional washing process of lactase was not necessary to inactivate the residual enzyme. In a subsequent study, the vegetative cells of microorganisms were completely killed with 10 ppm for 10 min treatment by ozone. The present study provides evidence that ozone treatment can be used as an inactivation and a sterilization process. In addition, these results suggest that acceptable milk products containing lactase microcapsules made by PGMS can be prepared with ozone treatment.

• 한국토양비료학회지
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• 제50권2호
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• pp.71-80
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• 2017

This study was conducted to investigate the application effect of Lysobacter antibioticus HS124 (gelatinase and chitinase producing microorganism; GCM) for the improvement of soybean yield and control of stink bug. Our results showed that the yield of GCM-treated soybean increased by 17.0, 20.3, 19.0, and 25.6% in the experimental field sites of Muan-gun, Sunchang-gun, Gwangju 1, and Gwangju 2, respectively, compared to the yield of the soybean obtained by conventional practice treatment (CPT); however in the Gimjae-si, the yield decreased by 10.6%. Results in both pods and seeds $plant^{-1}$ were significantly increased in Gwangju 2 by the GCM cultured broth treatment (GCMT). Ratio of 3 seeds $pod^{-1}$ in Sunchang-gun was statistically significant between GCMT and CPT, however, the result in the other field showed no significance. Germination rate was only statistically improved by GCMT in Gwangju 2 field site. GCMT reduced the appearance of stink bug in all experimental field sites except in Gimjae-si. The soybean seed damage by stink bug was no significance in all of treatments. Therefore, GCMT could improve the productivity of soybean and also control the infestation of stink bug.

• 동아시아식생활학회지
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• 제21권6호
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• pp.897-904
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• 2011

For set up the processing method of Byeo-Nuruk, we investigated the quality characteristics of Byeo-Nuruk according to the mixture ratio of rice and wheat, as well as the addition rate of moisture. After 12 hours of incubation, the temperature of Nuruk increased dramatically and reached a maxium temperature at 36 hours. After 36 hours, the temperature decreased gradually and was maintained at about $31{\sim}38^{\circ}C$. The ranges of pH and titratable acidity of Byeo-Nuruk were 4.85 to 7.42 and 1.0 to 2.3, respectively. A higher content of wheat ratio in Byeo-Nuruk, was associated with higher enzyme activities of ${\alpha}$-amylase, glucoamylase, and acidic-protease. Further, at a 70% wheat ratio, a 25% addition rate of moisture showed the highest enzyme activity. In the mixture ratio between rice and wheat, the 50:50 and 30:70 treatments contained the highest levels of microorganisms.

• 유기물자원화
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• 제2권1호
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• pp.51-64
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• 1994

본보는 종합병원에서 발생되는 유기성쓰레기인 음식물찌꺼기를 미생물에 의해 고속발효공법을 동원하여 24~48시간 이내에 퇴비 또는 토양개량제로 전환시키기 위한 중간처리방법이 된다. 처리를 위한 발효조건은 함수율이 60%, 발효온도는 $50{\sim}60^{\circ}C$, 산소공급을 위한 송풍량은 $50{\sim}200L/min{\cdot}m^3$ 정도가 필요하다. 함수율을 60%정도로 조정하기 위해서 두부비지와 톱밥을 사용하였고 고속발효에 필요한 미생물균주는 호기성 균주로서 발효물의 전체중량의 1/300정도 투입하였다. 운전방법은 1차발효가 끝난 다음 감량 및 인출량을 체크하고 그 상태에서 새로운 음식물찌꺼기를 투입하는 형식을 취하였다. 발효물에 대한 감량은 비교군과 실험군에서 각각 56.6%와 35.6~47.7%를 나타내었고 발효물에 대한 감량은 bulking agent에 따라 차이가 다소 있었으나 대략 50% 수준이었다. 발효시에 발생되는 탄산가스 농도는 1,000~1,500ppm 정도였고 연속발효일수록 황색에서 갈색, 검은색으로 변하였다. 발효물에 대한 퇴비화의 이화학적 분석에서는 pH는 약산성, 함수율은 10%미만이였고, 수분조정제에 따라 퇴비화 시간과 T-N, $P_2O_5$, $K_2O$에는 차이가 있었고, C/N 비에도 차이가 컸다. 보편적으로, 음식물찌꺼기를 대상으로한 고속발효화는 퇴비 또는 토양개량제로서 가치는 있으나 완숙정도가 부족하기 때문에 중간처리 방법으로서는 가능하다고 사료된다.

• 한국식생활문화학회지
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• 제13권2호
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• pp.119-126
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• 1998

This study was carried out to give some help for housewives recognizing the desirable purchase of processed foods and food additives. This results were abtained as follows; In case of purchase action for processed foods of housewives confirmation of manufacturing date was the highest point(4.62). When housewives bought processed foods they considered the taste of them as first, and frequencies of processed foods intake showed the ratio of 46.6%, also it was shown to be used once a week. The order for use of processed foods were milk, milk products(butter, cheese, yoghurt, lactic bacterium beverage) 40.2% >canned foods 22.6% >meat products(ham, sausage, bacon) 20.9% > jelled fish 16.3%. Most of housewives wanted to have the knowledge and information for food additives at the highest point(4.11). The interest about food additives of housewives was shown to the order of synthetic preservative 3.86 >chemical seasoning 3.74 >synthetic sweetener 3.59 >synthetic coloring agent 3.53. Also, it was shown to be thought that the hazard factors effected on food safety were agricultural chemical residue(30.9%), environmental pollution(25.2, food additives(23.0%), and microorganism contamination(20.9%).

• 유기물자원화
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• 제5권2호
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• pp.29-37
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• 1997

높은 수분으로 인해 매립 또는 소각에 의한 처분이 부적절한 음식물 쓰레기를 퇴비화하여 자원 재순환형으로 사용할 경우, 자원, 환경, 농업문제에 이르기까지 다각적으로 많은 이점을 가져다 준다. 본 연구의 목적은 소규모 퇴비화 장치를 이용하여 초기 함수율을 달리하였을 때 음식물 쓰레기의 퇴비화 과정을 평가하고 미생물 첨가제를 개발하여 활성도를 평가함으로써 소규모 퇴비화 장치의 최적 운전 조건을 도출하는 것이다. 음식물 쓰레기의 무게 감량은 75~85%로써 대부분 수분의 증발에 기인하는 것으로 나타났으며, 초기 함수율을 25%, 45%, 60%로 달리하였을 때 건조상의 C/N비는 15.4, 14, 12.9로 퇴비 판정 기준에 부합하였다. 기존에 사용되던 상업용 균주에 대체할 수 있는 균주를 개발하여 활성도를 평가한 경우, 개발 균주인 PNU2가 $CO_2$농도 기준으로 우수한 것으로 나타났다. 그러나 화학적 분석에 의한 최종 완숙 단계를 결정하기에는 다소 미흡하였다.

• Journal of Microbiology and Biotechnology
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• 제34권9호
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• pp.1803-1809
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• 2024

Leuconostoc lactis DMLL10 is a microorganism specific to kimchi fermentation. In this study, we sought to evaluate the toxicity of this strain, which was newly isolated from kimchi, to determine its safety as a food ingredient. Bacterial reverse mutation assay, chromosomal aberration assay, and mammalian cell in vitro micronucleus assay were performed to assess the genetic toxicity of Leu. lactis DMLL10. The strain did not induce mutagenicity in Salmonella typhimurium TA98, TA100, TA1535, TA1537, or Escherichia coli WP2uvrA, with or without metabolic activation of S9 mixture. The oral administration of Leu. lactis DMLL10 also did not significantly increase the number of micronucleated polychromatic erythrocytes, or the mean ratio of polychromatic to total erythrocytes. Additionally, Leu. lactis DMLL10 did not cause a significant chromosomal aberration in CHU/IL cells in the presence or absence of S9 activation. Therefore, Leu. lactis DMLL10 can be suggested as a functional food ingredient with reliability and safety.

• Applied Biological Chemistry
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• 제40권2호
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• pp.107-111
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• 1997

Protopectinase(PPase)는 식물 세포벽의 protopectin을 분해하는 효소로서 식품의 가공에 이용될 수 있는 효소이다. PPase의 산업적 응용을 위하여 PPase를 생산하는 미생물 Bacillus subtilis IFO 12113의 배양여액에 acetone, methanol, ethanol을 각각 처리하여 PPase를 회수하는 연구를 수행하였다. Acetone의 경우, 배양여액 대 acetone을 1:1 (v/v) 비율로 첨가했을 때 효소는 59.2%가 회수되었으며 정제도는 1.7배 이었다. Methanol의 경우, 1:2(v/v) 비율로 처리하였을 때, 효소는 100% 회수되었으며 비활성도로 본 정제도는 4.0배 증가하였다. Ethanol의 경우에 1 :0.5 (v/v) 비율로 처리한 것을 원심분리시켜 침전물을 제거하고, 그 상등액에 최종 ethanol 비율을 1:1(v/v)까지 처리했을 때, 효소의 회수율은 68%를 나타냈으며 비활성도는 13.5배 증가하였다. 세균의 배양여액으로부터 PPase의 회수에는 methanol 처리가 가장 효율적이었으나, 산업적 응용을 위하여 정제효과까지 고려하면 ethanol처리가 가장 적절하였다.