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가정용 음식물처리기는 음식물 쓰레기 부피와 무게를 감량할 수 있으며, 따라서 음식물쓰레기 처리 과정의 온실가스 배출 저감 잠재력을 지닌 효과적인 수단이 될 수 있다. 그러나 음식물처리기 이용에 전력이 소비되기 때 문에 탄소배출 감축 효과를 직관적으로 판단하기 어렵다. 따라서 본 연구는 가정용 음식물처리기의 탄소배출 감 축 성과를 평가함으로써 기후위기 대응을 위한 수요자 측면의 전략으로서의 효과성을 검증하고자 하였다. 또한 가정용 음식물처리기 보급률은 전체 가구의 10%로 낮은 수준에 머물고 있어서, 이에 대한 소비자 인식 및 특성 의 통합적 이해를 통해, 음식물처리기 보급 전략을 제안하고자 한다. 연구문제는 다음과 같다. 첫째, 건조분쇄형 및 미생물형 처리 방식은 탄소배출량에 어떠한 차이가 있는가? 둘째, 음식물처리기에 대한 소비자 인식의 주요 주제는 무엇인가? 셋째, 음식물처리기 사용과 유의한 연관이 있는 소비자 특성은 무엇인가? 본 연구는 연구문제 별로 세 개의 연구로 구성되었다. 첫째, 건조분쇄형 및 미생물형 처리기의 탄소배출량을 전처리, 집하, 운송, 최 종 처리 단계별로 추정 후, 일반적인 음식물쓰레기 처리 방식과 비교하여 기후위기 대응 수요 측면의 전략으로서 의 실효성을 확인하였다. 둘째, 음식물처리기 이용자의 소비자 댓글 데이터에 대한 토픽모델링 분석을 실행하여 음식물처리기에 대한 소비자의 인식을 탐색하였다. 셋째, 2023 식품소비행태조사 자료를 분석하여 음식물처리기 이용 영향 요인을 파악하고자 로짓분석을 실행하였다. 주요 연구결과는 다음과 같다. 첫째, 음식물처리 방식별 탄소배출량을 추정한 결과, 미생물형은 기존 방식 대비 약 74% 절감된 반면, 건조분쇄형은 기존 방식 대비 약 6.29배 증가하는 것으로 나타났다. 둘째, 소비자는 음식물처리기의 탄소배출과 관련된 친환경성을 인식하지 못하 였다. 셋째, 가구 내 음식물 소비량이 많고, 단독주택 또는 연립/다세대주택에 거주하는 소규모 기혼 가구에서 음식물처리기 사용 가능성이 유의하게 높게 나타났다. 본 연구는 건조분쇄형보다 미생물형 음식물처리기 확산을 통해 음식물쓰레기 처리 과정의 탄소배출을 감축할 수 있으며, 이에 대한 소비자 인식 개선이 필요함을 시사한다. 또한 음식물쓰레기 수요자의 특성을 확인하였다는 점에서 연구의 의의를 찾을 수 있다. 이상의 결과는 기후위기 대응 수요자 측면의 소비자 정책 및 교육 전략 수립에 유용하게 활용될 수 있을 것으로 기대된다.

Household food waste decomposers are gaining attention as a potential means of reducing greenhouse gas emissions, as they help decrease the volume and weight of food waste. However, their emission reduction potential is often evaluated based solely on the degree of waste reduction, which overlooks carbon emissions generated from electricity consumption during operation. This study aims to verify the environmental friendliness of household food waste decomposers in terms of their net carbon emission reduction effects. With a current penetration rate of approximately 10%, the study also proposes effective dissemination strategies based on consumer perceptions and characteristics, particularly for environmentally effective models. This study addresses the following research questions: (1) How do drying-grinding and microbial types of food waste decomposers differ in carbon emissions compared to conventional disposal methods? (2) What are the key themes in consumer perceptions? (3) What consumer characteristics influence the likelihood of adoption? Carbon emissions for both decomposer types were estimated across four stages: pre-treatment, collection, transportation, and final disposal, and compared to conventional methods. Topic modeling was applied to consumer-generated comments to explore perceptions, and logistic regression analysis was conducted using the 2023 Food Consumption Behavior Survey. The results showed that microbial decomposers reduced carbon emissions by approximately 74%, while drying-grinding decomposers emitted 6.29 times more carbon due to high electricity use. Environmental benefits such as carbon reduction were not widely recognized by consumers, highlighting the need for increased public awareness. Higher adoption potential was observed among small-sized, married households with high food consumption, particularly those in singlefamily or multi-family housing. These findings offer valuable implications for climate change policy, eco-friendly product development, and sustainable consumption promotion.

미생물제 살포가 양돈농장의 악취저감 효과를 검증하기 위하여 1,000두, 3,000두 및 5,000두 규모의 상업적인 양돈 농장에서 임신사, 분만사, 자돈사 및 육성비육사로 구분하 여 비교하였다. 미생물제를 24시간, 72시간 간격으로 살포하거나 물 만 살포한 돈사 내부에서 암모니아와 황화수소 를 측정하였다. 미생물제 24시간 간격 살포가 모든 농장에 서 암모니아(p<0.01)와 황화수소(p<0.05)의 평균 농도가 가 장 낮게 나타났다. 돈사유형별 미생물제 24시간 간격 살포 에 의한 암모니아 농도 변화는 임신사 9.7에서 6.4ppm으 로 분만사 11.0에서 1.8ppm으로 자돈사 17.0에서 9.2ppm 및 육성비육사 15.3에서 8.8ppm으로 떨어져 분만사 (p<0.01)에서 가장 큰 폭의 저감 효과가 나타났으며, 자돈 사(p<0.05), 육성비육사, 임신사 순이었다. 미생물제 24시간 간격 살포는 5,000두, 3,000두 및 1,000두 규모 농장의 암모 니아 농도를 각각 19.9에서 10.4ppm으로, 11.1에서 4.1ppm 및 8.8에서 5.1ppm으로 떨어뜨리는 결과를 나타내었다 (p<0.01). 결론적으로 양돈농장의 악취저감을 위한 미생물 제 살포는 매우 유용한 기술이며, 미생물제는 매일 살포하 는 것이 가장 효과적이고 길어도 3일 이내 간격을 유지하 여야 할 것으로 사료된다.

The present trial verified the effects of spraying microbial agents on odor reduction in commercial pig farms of different operating sizes and barn types. Farms without microbial agent spraying and those sprayed with microbial agents at two different intervals were compared. The treatments included spraying of water alone every day or a mixture of water plus microbial agent at 24 and 72 h intervals. The experimental farms were divided according to size into 1,000-, 3,000-, and 5,000-head farms and according to barn type into gestation, farrowing, nursery, and grower-finisher farms. To compare odor concentration within each housing barn, ammonia and hydrogen sulfide gas levels were measured. The average concentrations of ammonia (p<0.01) and hydrogen sulfide (p<0.05) gas were the lowest in all types of farms sprayed with the microbial agent at a 24 h interval. In farms sprayed with the microbial agent at a 24 h interval, the decrease in ammonia concentration according to barn type was in the following order: farrowing (p<0.01) (11.0 to 1.8 ppm), nursery (p<0.05) (17.0 to 9.2 ppm), grower-finisher (15.3 to 8.8 ppm), and gestation (9.7 to 6.4 ppm) farms. Moreover, spraying the microbial agent at a 24 h interval significantly (p<0.01) decreased ammonia concentration from 19.9 to 10.4 ppm, from 11.1 to 4.1 ppm, and from 8.8 to 5.1 ppm in 5,000-, 3,000-, and 1,000-head farms, respectively. Overall, spraying microbial agents every day may be the most effective method to reduce odor in commercial pig farms.

Gellan형 미생물 다당류를 생산하는데 관련된 기초 자료를 얻기 위하여 배지조성, 배양온도 및 초기 pH등에 대한 플라스크 실험을 수행하였으며 이를 근거로 회분식, 유가식 및 연속배양을 실시하였다. 또한 배양액의 비뉴우튼성 유체 특성을 조사하였고 이때의 교반동력을 측정하였다. 플라스크 배양을 통하여 얻은 결과를 이용하여 회분식 배양의 최적조건을 확립하였으며 각종 metabolic parameter들을 추정하였다. 유가식과 연속식 배양을 통하여 생산성 향상을 시도한 결과 유가식과 연속식 배양에서 생산성 향상을 꾀할 수 있었다. 고점성 배양액에서의 물질전달 장해현상을 극복하기 위한 일련의 연구가 필요하다고 사료되며 이로부터 생산성 향상을 크게 기대할 수 있을 것으로 보인다

The Gellan-type polysaccharide produced by Pseudomonas elodea(ATCC 31461) is one of the new heteropolysaccharides, having useful properties as gelling, suspending, stabilizing, emulsifying and binding agents in aqueous systems. Medium compositions for growth stage and production stage are improved. The problems of low cell concentration and poor productivity in highly viscous fermentation were attributed to inadequate mixing accompanied by insufficient oxygen transfer. During continuous culture, cell growth and polysaccharide production were greatly affected by the apparent viscosity, and they showed oscillation behavior, i.e. as the product concentration increases, cell concentration decreases. With improved culture conditions, the productivity of continuous culture increased up to 0.6g/l/hr(6-fold that of batch culture ) at dilution rate, D=0.14hr-1.

Microbial fuel cells (MFC) stacked with bipolar plates have been constructed and their performance was tested. In this design, single fuel cell unit was connected in series by bipolar plates where an anode and a cathode were made in one graphite block. Two types of bipolar plate stacked MFCs were constructed. Both utilized the same glucose oxidation reaction catalyzed by Gram negative bacteria, Proteus vulgaris as a biocatalyst in an anodic compartment, but two different cathodic reactions were employed: One with ferricyanide reduction and the other with oxygen reduction reactions. In both cases, the total voltage was the mathematical sum of individual fuel cells and no degradation in performance was found. Electricity from these MFCs was stored in a supercapacitor to drive external loads such as a motor and electric bulb.

Two hollow fiber membrane biofilm reactors (HF-MBfRs) were operated for autotrophic nitrification and hydrogenotrophic denitrification for over 300 days. Oxygen and hydrogen were supplied through the hollow fiber membrane for nitrification and denitrification, respectively. During the period, the nitrogen was removed with the efficiency of 82-97% for ammonium and 87-97% for nitrate and with the nitrogen removal load of 0.09-0.26 kg NH₄⁺-N/m³/d and 0.10-0.21 kg NO₃^--N/m³/d, depending on hydraulic retention time variation by the two HF-MBfRs for autotrophic nitrification and hydrogenotrophic denitrification, respectively. Biofilms were collected from diverse topological positions in the reactors, each at different nitrogen loading rates, and the microbial communities were analyzed with partial 16S rRNA gene sequences in denaturing gradient gel electrophoresis (DGGE). Detected DGGE band sequences in the reactors were correlated with nitrification or denitrification. The profile of the DGGE bands depended on the NH₄⁺ or NO₃^- loading rate, but it was hard to find a major strain affecting the nitrogen removal efficiency. Nitrospira-related phylum was detected in all biofilm samples from the nitrification reactors. Paracoccus sp. and Aquaspirillum sp., which are an autohydrogenotrophic bacterium and an oligotrophic denitrifier, respectively, were observed in the denitrification reactors. The distribution of microbial communities was relatively stable at different nitrogen loading rates, and DGGE analysis based on 16S rRNA (341f /534r) could successfully detect nitrate-oxidizing and hydrogen-oxidizing bacteria but not ammonium-oxidizing bacteria in the HF-MBfRs.

Yogurt is a food produced by bacterial fermentation of milk and the bacteria used to make it are known as "yogurt cultures". Most of them belong to probiotics such as Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus bacteria. Domestic fermented milk market is increasing and about 30 companies are producing yogurt. The purpose of this study was to analyze the quality characteristics of domestic commercial semisolid type yogurt. We collected 20 types of commercial yogurt at local markets. Physicochemical properties including pH, sugar content, acidity, viscosity and microbial characteristics of lactic acid bacteria counts were measured. The yogurt showed pH 4.5, 7.4~18.1% of sugar contents, 0.6~1.3% of total acids and 282~748 cP of viscosities. In the microorganism populations, lactic acid bacteria count were 6.5~11.5 Log CFU/mL and anaerobic lactic acid bacteria count were 7.2 ~ 11.1 Log CFU/mL. The quality characteristics were different depending on the constituents of the sample and the microorganisms used. These results are related to the quality characteristics of yogurts which are useful information about identifying new trends in domestic fermented milk industry.

An experiment was conducted with eight growing sheep (average initial weight 20.6 kg and average final weight 23.7 kg) in a $4{\times}4$ Latin square design to study the effect of type of forage supplementation to a basal diet of rice straw (ad libitum) and cassava (Manihot esculanta, approximately 9 g of dry matter $(DM).kg^{-0.75}{\cdot}day^{-1}$) on voluntary intake, digestion, rumen microbial protein synthesis and daily weight gain. Forages used were Leucaena (L, Leucaena leucocephala), Gliricidia (G, Gliricidia maculata) and Tithonia (T, Tithonia diversifolia, wild sunflower) at a DM supplementation level of approximately $13g.kg^{-0.75}.day^{-1}$. Organic matter intake was 40.4, 55.5, 55.0 and $54.9g{\cdot}kg.^{-0.75}{\cdot}day^{-1}$ for control (C, ad libitum straw and cassava), L, G and T. respectively, significantly lower for C than for the supplemented diets. Intake of supplementary forage had also a significantly positive effect on voluntary rice straw intake. All forage supplemented diets showed a significantly higher whole diet organic matter digestion than C ($488g{\cdot}kg^{-1}$), while T ($557g{\cdot}kg^{-1}$) differed significantly from L ($516g{\cdot}kg^{-1}$) but not from G ($526g{\cdot}kg^{-1}$). Daily weight gain was -1.7, 5.2, 5.4 and $4.7g{\cdot}kg^{-0.75}$, for C, L, G and T. respectively, significantly lower for C than for the forage-supplemented diets. Efficiency of microbial protein synthesis estimated from urinary excretion of purine derivatives was lower for C (3.8 g microbial N. (kg digestible organic matter intake $(DOMI))^{-1}$ than for the forage supplemented diets (11.3, 9.0 and 9.4 g microbial $N.(kg\;DOMI)^{-1}$ for L, G and T. respectively).

Antidiabetic effects of a novel microbial biopolymer (PGB) 1 excreted from new Enterobacter sp. BL-2 were tested in the db/db mice. The animals were divided into normal control, rosiglitazone (0.005%, wt/wt), low PGB1 (0.1%, wt/wt), and high PGB1 (0.25%, wt/wt) groups. After 5 weeks, the blood glucose levels of high PGB1 and rosiglitazone supplemented groups were significantly lower than those of the control group. In hepatic glucose metabolic enzyme activities, the glucokinase activities of PGB1 supplemented groups were significantly higher than the control group, whereas the PEPCK activities were significantly lower. The plasma insulin and hepatic glycogen levels of the low and high PGB1 supplemented groups were significantly higher compared with the control group. Specifically, the insulin and glycogen increases were dose-responsive to PGB1 supplement. PGB1 supplement did not affect the IPGTT and IPITT compared with the control group; however, rosiglitazone significantly improved IPITT. High PGB1 and rosiglitazone supplementation preserved the appearance of islets and insulin-positive cells in immunohistochemical photographs of the pancreas compared with the control group. These results demonstrated that high PGB1 (0.25% in the diet) supplementation seemingly contributes to preventing the onset and progression of type 2 diabetes by stimulating insulin secretion and enhancing the hepatic glucose metabolic enzyme activities.

An in vitro experiment was conducted to evaluate the differences in microbial activity of five faecal inocula from weaned pigs and one faecal inoculum from unweaned pigs in combination with 6 substrates. The substrates tested were negative control diet, corn, soybean meal, oligofructose (OF), ground chicory roots and a mixture (60% chicory pulp and 40% OF). The inocula used were derived from pigs fed either a corn-soy based diet without antibiotics (NCON), the NCON diet supplemented with oligofructose (OF), a mixture of chicory pulp (40%) and OF (60%) (MIX), ground chicory roots (CHR) or the NCON diet supplemented with antibiotics (PCON). The cumulative gas production measured fermentation kinetics and end products, such as total gas production, ammonia and volatile fatty acids, were also determined. Both the substrate and the inoculum significantly affected the fermentation characteristics. The cumulative gas production curve showed that different substrates caused more differences in traits of fermentation kinetics than the different inocula. Inocula of weaned pigs gave a significantly higher VFA production compared to the inoculum from unweaned animals, whilst the rate of fermentation and the total gas produced did not differ. OF showed the highest fermentation kinetics and the lowest $NH_3$, pH and OM loss compared to other substrates. It was concluded that the microbial activity was significantly affected by substrate and inoculum. Inoculum from weaned pigs had more potential for microbial fermentation of the carbohydrate ingredients and oligofructose than that of unweaned pigs. A combination of high and low polymer inulin may be more beneficial to the gut ecosystem than using high- or low-polymer inulin alone.

In the previous research, a biomonitoring system using two compartment microbial fuel cells was developed; electrochemically active bacteria in a microbial fuel cell could oxidize organic materials to simultaneously generate electric current without addition of any mediator. In this work, a novel membrane electrode assembly (MEA) type biomonitoring sensor was equipped to improve sensitivity of the biomonitoring system. The membrane electrode assembly (MEA) cathode was assembled with a proton exchange membrane and a cathode electrode by hot press method. Electrochemical active bacteria of the sensor were enriched with activated sludge. This electricity generation shows positive correlations with BOD concentration. In the presence of toxic material, such as Cu, Pb, Se and As metabolism of electrochemically active bacteria was inhibited and consequently decreased electricity generation from microbial fuel cell. If the patterns of electricity generation are compared according to the material added, the proposed method can be utilized to identify the presence of toxicity of water sample.

Microorganism plays important roles in plant growth and health. Organic farming is known to play positive effect on microbial abundance and activity. Our study investigated the microbial characteristics of soil in various cultivation types, such as fields, orchards, rice paddies, and greenhouse. In this study we analyzed the soil chemical properties, microbial dehydrogenase activity, microbial carbon substrate utilization analysis and microbial community analysis using next-generation sequencing. As a result of soil chemical properties, organic matter content showed the highest value in orchard soil and the lowest value in greenhouse soil. Greenhouse soil showed the highest level of EC value. Dehydrogenase activity and community level physiological profiling (CLPP) were the highest in the farmland soil. Microbial carbon substrate utilization analysis, high values were shown in farmland soil and orchards and low values were shown in rice paddies and greenhouse soil. This was thought to be due to the influence of microbial community distribution. Bacterial community analysis show that Pseudomonadota, Bacilota and Chloloflexota were predominant phylum in all type fields. In the case of orchards, it is thought that Psuedomonadota, which increases when the organic matter content is rich, showed a high distribution, and in the case of paddies Chloroflexota which increases when the organic matter content is low, showed a high distribution. The numbers of operational taxonomic units (OTU, defined at 97% similarity) and species richness were the highest in the farmlands soil. These results speculate that bacterial community were highly correlated with microbial enzyme activity. Additionally, various soil chemical properties such as available phosphorus and organic matter were main drivers for bacterial community composition. This study show that soil environment and microbial activity are highly correlated, suggesting that proper soil management is necessary.