• 미생물학회지
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• 제29권4호
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• pp.250-257
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• 1991

An obligate methanol-oxidizing bacterium, Methylobacillus sp. strain SK1, which grows only on methanol was isolated from soil. The isolate was nonmotile Gram-negtive rod. It does not have internal membrane system. The colonies were small, whitish-yellow, and smooth. The guanine plus cytosine content of the DNA was 48 mol%. Cellular fatty acids consisted predominantly of large amounts of straight-chain saturated $C_{16:0}$ acid and unsaturated $C_{16:1}$ acid. The major ubiquinone was Q-8, and Q-10 was present as minor component. The cell was obligately aerobic and exhibited catalase, but no oxidase, activity. Poly-.betha.-hydroxybutyrate, endospores, or cysts were not observed. the isolate could grow only on methanol in mineral medium. Growth factors were not required. The isolate was unable to use methane, formaldehyde, formate, methylamine, and several other organic compounds tested as a sole source of carbon and energy. Growth was optimal at 35.deg.C and pH 7.5. It could not grow at 42.deg.C. The doubling time was 1.2h at 30.deg.C when grown with 1.0%(v/v) methanol. The growth was not affected by antibiotics inhibiting cell wall synthesis and carbon monoxide but was completely suppressed by those inhibiting protein synthesis. Methanol was found to be assimilated through the ribulose monophosphate pathway. Cytochromes of b-, c-, and o- types were found. Cell-free extracts contained a phenazine methosulfate-linked methanol dehydrogenase activity, which required ammonium ions as an activator. Cells harvested after the late exponential phase seemed to contain blue protein.ein.

• 한국폐기물자원순환학회지
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• 제35권8호
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• pp.731-743
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• 2018

This study was performed to test the feasibility of thermophilic ($55^{\circ}$) co-digestion of municipal sewage sludge and food wastes. The management variables of co-digestion were the mixed ratios of municipal sewage sludge and food waste hydraulic retention times (HRTs). During the operation of thermophilic co-digestion, the reactor pH ranged from 7.0 to 7.5 and the reactor alkalinity remained above 3,200 to 4,000 mg/L as $CaCO_3$. The volatile fatty acids concentration increased as the HRT shortened from 20 days to 10 days and the mixture ratio increased to 1:4, but did not reach toxic levels for co-digestion of sewage sludge and food wastes. Methane productivity increased gradually as the organic loading rate increased. Maximum methane productivity reached 1.03v/v-d at an HRT of 10 days and at the mixture ratio of 1:4. The TVS removal efficiency decreased from 70.6% to 58.3% as the HRT shortened from 20 days to 10 days. TVS removal efficiency ranged from 57.0% to 77% during the entire operation. It is likely that thermophilic co-digestion of sewage sludge and food wastes is a very effective method both to environmentally treat food waste and to economically produce gas for energy.

• Asian-Australasian Journal of Animal Sciences
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• 제24권1호
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• pp.130-136
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• 2011

Methane is known to be one of the major greenhouse gases. On a global scale, livestock farming may contribute 18% of total greenhouse gas emissions. Though methane contribution is less than 2% of all the factors leading to global warming, it plays an important role because it is 21 times more effective than carbon dioxide. Methane emission is a direct result of the fermentation process performed by ruminal microorganisms and, in particular, the archael methanogens. Reducing methane emission would benefit both ruminant production and the environment. Methane generation can be reduced by electron-sink metabolic pathways to dispose of the reducing moieties. An alternative way for methane control in the rumen is to apply inhibitors against methanogens. Generating methane from manure has considerable merit because it appears to offer at least a partial solution to two pressing problems-environmental crisis and energy shortage. An obvious benefit from methane production is the energy value of the gas itself. Control of methane emission by rumen microbes in Korea has mainly been focused on application of various chemicals, such as BES and PMDI, that inhibit the growth and activity of methanogens in the rumen. Alternatives were to apply long-chain polyunsaturated fatty acids and oils with or without organic acids (malate and fumarate). The results for trials with methane reducing agents and the situation of biogas production industries and a typical biogas plant in Korea will be introduced here.

• Asian-Australasian Journal of Animal Sciences
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• 제13권10호
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• pp.1399-1406
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• 2000

A continuous culture study was conducted to determine the impact of ruminal degradable soy protein (S-RDP) level and dilution rate (D) on growth of ruminal non-structural carbohydrate-fermenting microbes. Corn starch, urea and isolated soy protein (ISP) were used to formulate three diets with S-RDP levels of 0, 35 and 70% of total dietary CP. Two Ds were 0.03 and $0.06h^{-1}$ of the fermenter volume in a single-effluent continuous culture system. As S-RDP levels increased, digestibilities of dietary dry matter (DM), organic matter (OM) and crude protein (CP) linearly (p=0.001) decreased, whereas digestion of dietary starch linearly (p=0.001) increased. Increasing D from 0.03 to $0.06h^{-1}$ resulted in decreased digestibilities of dietary DM and OM, but had no effect on digestibilities of dietary starch (p=0.77) and CP (p=0.103). Fermenter pH, the concentration of volatile fatty acids (VFA) and daily VFA production were unaffected (p=0.159-0.517) by S-RDP levels. Molar percentages of acetate, propionate and butyrate were greatly affected by S-RDP levels (p=0.016-0.091), but unaffected by D (p=0.331-0.442). With increasing S-RDP levels and D, daily bacterial counts, daily microbial N production (DMNP) and microbial efficiency (MOEFF; grams of microbial N produced per kilogram of OM truly digested) were enhanced (p=0.001). The increased microbial efficiency with increasing S-RDP levels is probably the result of peptides or amino acids that served as a stimulus for optimal protein synthesis. The quantity of ruminal degradable protein from soy proteins required for optimum protein synthesis of non-structural carbohydrate-fermenting microbes appears to be equivalent to 9.5% of dietary fermented OM.

• Applied Biological Chemistry
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• 제36권5호
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• pp.339-345
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• 1993

우리나라 사람들의 기호에 맞으면서 저장성이 있는 정어리 조미가공품의 제조를 위하여 초절임 중 품질변화에 대하여 실험하였다. Dressed한 정어리를 포화식염수에 염지한 결과 48시간까지는 수분함량의 경우 감소하였고, 염도, 휘발성염기질소함량 및 조직감의 경우 증가하였으나, 그 이상의 시간에는 거의 변화가 없었다. 정어리 초절임중에는 수분 및 회분은 거의 변화가 없었고, pH는 상당히 감소하였다. 가공 중 생균수는 감소하였고, histamine함량은 변화가 없어 식품위생적으로 안전하다고 판단되었다. TBA값, 과산화물값 및 지방산조성의 결과로 볼 때 염지한 정어리를 항산화제가 함유되어져 있는 조미액에 초절임하여 제조하는 경우 가공 중 지질산패가 상당히 억제되었다. 정어리 초절임제품의 맛성분은 함량으로 미루어 보아 신맛의 유기산과 histidine, lysine, glutamic acid 및 arginine과 같은 유리아미노산 그리고 IMP와 같은 핵산관련물질이 맛의 주체를 이루고, 총 creatinine, betaine 및 TMAO 등이 보조적으로 맛에 관여하였다.

• 한국식품과학회지
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• 제28권3호
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• pp.558-565
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• 1996

감마선 조사된 대투의 이화학적 품질 특성에서 일반성분 지방산 조성 및 무기질 성분은 모든 조사선량에서 변화가 없었으며, 질소 용해도파 추출성 phents 및 phytate 함량은 5 kGy까지의 조사군 사이에는 차이가 없었으나. 10 kGy와 20 k0y의 고선량 조사군에서는 다소의 영향이 화인되었으며, 1년 저장후에는 모든 시험군에서 감소현상을 보였다. 산가 및 유기산 함량도 2.5 kGy 조사군까지는 비조사군과 차이가 없었으나 5kGy 이상 조사군에서는 증가하는 경향이었고, 1년 저장 후 모든 시험군에서 증가함을 보였다. 조사된 대두의 총 아미노산 함량과 조성은 10 kGy 선량까지는 변화가 없었으나, 10kGy 이상의 조사군에서 cysteine과 methionine의 감소를 나타내었다. 대두 색도는 감마선 조사선량의 증가와 저장기간의 경과로 명도와 황색도의 감소가 적색도의 증가를 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제5권4호
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• pp.687-693
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• 1992

The study was conducted to investigate the effect of soybean meal (SBM) supplementation on the voluntary intake of rice straw and ruminal fermentation characteristics. Balance trials were conducted with three Hapanese Corriedale wethers fed a rice straw alone (control), rice straw supplemented with 75 and 150 g of SBM/day in a $3{\times}3$ latin square design. Voluntary intake of rice straw in sheep fed both levels of SBM supplemented diets was significantly higher (p<0.05) than that in sheep fed control diet. Crude protein digestibility was significantly increased (p<0.05), but organic matter, crude fibre, neutral detergent fibre and acid detergent fibre digestibilities were not affected by SBM supplementation. Nitrogen balance was positive in sheep on both levels of SBM supplemented diets, but negative in animals on the control diet. Rumen ammonia and blood urea-nitrogen concentrations increased (p<0.05) as increasing level of SBM. Total volatile fatty acids, acetate, propionate, butyrate and valerate concentrations in rumen fluid were also significantly increased (p<0.01), but ruminal pH was decreased (p<0.05) by SBM supplementation.

• 대한유전성대사질환학회지
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• 제15권2호
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• pp.98-100
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• 2015

경쇄 acyl-CoA 탈수소효소 결핍증(short chain acyl-CoA dehydrongenase deficiency, SCAD)은 미토콘드리아에 존재하는 효소 중 하나인 경쇄 acyl-CoA 탈수소효소(short chain acyl-CoA dehydrongenase, SCAD)의 결핍으로 인하여 지방산 산화의 장애를 초래하는 대사질환이다. 이 질환의 임상증상은 성장 부전, 대사성 산증, 저혈당, 발달 지연, 발작 및 신경 근육 증상, 근력 저하 등 매우 다양하다. 저자들은 무증상 신생아에서 신생아 선별검사를 통해 혈청 C4-butyrylcarnitine이 증가하고 소변의 ethylmalonic acid가 증가된 소견이 관찰되어 경쇄 acyl-CoA 탈수소효소 결핍증을 진단하였다. 생후 8개월까지 특이 증상 없이 추적관찰 중으로 정상적인 성장과 발달을 보였기에 이에 증례를 보고하는 바이다.

• Journal of Biosystems Engineering
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• 제35권1호
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• pp.53-63
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• 2010

The performance of two serial completely stirred tank reactors (CSTRs) for treatment of swine manure (SM) with Chinese cabbage silage (CCS) was studied. The two CSTRs of 41 liters each were connected in series and first reactor was fed swine manure with Chinese cabbage silage in 3:1 proportion by VS basis. The FOS/TAC, methane content (%) and pH were utilized as the parameters for the digester stability control. The FOS/TAC value was found to be effective indicator for instant digester condition. The stability of reactors can be obtained with the FOS/TAC value up to 1.0 with accumulation of FOS value below 10,000 mg/L. Material exchange method was effective in transferring the excess volatile fatty acids (VFA) from the first reactor to the second one and maintaining stability in both the reactors. The biogas yield and the methane yield was 0.55-0.61 and 0.41-0.42 L/g VS fed, respectively, at organic loading rate (OLR) of 2.2-2.6 g VS/L with total HRT of 32 days.

• 환경위생공학
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• 제24권4호
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• pp.80-89
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• 2009

In the organic waste, food waste is the most difficult controls. In the study, food waste was treatmented to removal only the dockage. To decrease the hydrogen sulfide($H_2S$) in the produced biogas, iron chloride put in the anaerobic digester. Respectively treatment quantity of the food waste, content of the methane($CH_4S$) gas in the biogas, produced gases quantity, put in the quantity of the Iron chloride, pH, TS, Alkalinity, VFA, Ammonia. The results obtained from the experiment are as follows: 1. The produced biogases quantity/the treatment quantity of the food waste was $83.82{\sim}129.41m^3/ton$. 2. The content of the hydrogen sulfide($H_2S$) in the produced biogas is below of the 500ppm. The iron chloride put in the anaerobic digester. 200~300kg of the iron chloride put in the anaerobic digester at the steady-state. 400~850kg of the iron chloride put in the anaerobic digester at the unsteady-state. 3. Factor of the operator was the pH: 7.7~8.4, content of mathane: 55~65%. 4. TS(total solid) of the digestor sludge was 17~20%, Alkalinity was 38,500~41,750ppm, VFA(Volatile Fatty Acids) was 2,800~2,420ppm, Ammonia was 4,300~3,650ppm.