• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.529-532
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• 2001

Korean food waste, one of the abundantly available but environmentally problematic organic wastes in Korea, was utilized as solid-substrate by fungal strain Aspergillus niger ATcC 6275 for the production of enzymemixture containing amylase, cellulase and xylanase. The enzyme mixture can be used as high value-added animal feed. Solid-state fermentation method yielded a 84-fold enhancement in xylanase activity compared with submerged fermentation method. The effect of incubation period, incubation temperature, pH of medium, moisture content, inoculum size and enrichment of the medium with nitrogen and carbon sources were observed for optimal production of these enzymes The optimal amylase activity of 33.10 U/g, cellulase activity of 24.41 U/g, xylanase activity of 328.84 U/g were obtained at 8 days incubation with 50%(w/w) soy bean flake, with incubation temperature of $25^{\circ}C$, pH of 6.38, optimal moisture content of 55% and with inoculum size of $3.8{\times}10^6$spore/g. Enzyme activities were enhanced when ImM $CaSO_4$, 2% Malt extract and 2% galactose were added as mineral, nitrogen and carbon enrichment respectively.

• 한국식품과학회지
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• 제22권6호
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• pp.668-674
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• 1990

대두, 수수, 대두-수수 혼합곡물 템페를 인도네시아의 전통적인 종균(LARU ; mixed cultures of Rhizopus oligosporus)를 사용하여 제조하였다. 발효가 끝난 후 대두 템페와 대두-수수 혼합템페는 단백질과 섬유질의 양이 발효시키지 않은 대조군 시료보다 증가하였고, 지방 함량은 수수템페와 대두-수수 혼합템페의 경우 약간 증가하였다. 발효가 진행함에 따라 3가지 형태의 템페 모두가 pH, 수용성 고형분, 수용성 질소 함량이 증가한 반면 총고형분 함량에는 큰 변화가 없었다. 트립신억제제 활성(TIA)과 피트산 함량은 발효 32시간 후 감소되었다. 이는 Rhizopus oligosporus 균이 대두를 발효시키는 과정에서 트립신억제제와 피트산을 분해하는 분해능을 가지고 있음을 제시하는 결과이다. 티아민과 나이아신 함량이 3가지 형태의 템페 모두에서 증가하였다. 32시간 발효 후 대두, 수수, 대두-수수 혼합템페 모두에서 총아미노산 함량은 감소하였고 아미노산 중 리신, 발린, 티로신, 알라닌 등이 증가하였고 세린과 글루탐산 이 감소하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제11권5호
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• pp.608-619
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• 1998

The small and the large intestine of swine represent the organs that extract nutrients from feedstuffs through digestion and fermentation and that allow their absorption and incorporation into the blood circulation. Special attention is directed towards the small intestine of young pigs since the transition to a solid diet at weaning exerts major impacts on the structural and functional integrity of the small intestine. Dietary factors involved in postweaning changes of gut morphology and biochemistry such as removal of bioactive compounds in sows milk at weaning, anti-nutritional factors in weaner diets, dietary fiber and the role of voluntary feed intake will be elucidated. The microbial function of the large intestine which is carried out by a diverse population of microorganisms is dependent on substrate availability. Short chain fatty acids as main fermentation products contribute to the energy supply of the host but they are also important for the maintenance of the morphological and functional integrity of the epithelium in the colon. As a result of bacterial nitrogen assimilation in the large intestine, nitrogen is shifted from the urinary to the fecal excretion route thus saving metabolic energy to the pig because less ammonia would become available for conversion to urea.

• 한국식품과학회지
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• 제22권7호
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• pp.786-792
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• 1990

어육을 발효기질로 풍미물질 생산 가능성을 검토하기 위하여 명태육 단독으로 혹은 명태육에 콩을 첨가한 발효기질에 Aspergillus oryzae에 속하는 3균주를 각각 접종, 발효하여 정미성분의 변화와 발효추출액을 관능 검사하였다. 사용한 균주는 모든 기질에서 왕성하게 증식하여 7일간 발효된 명태육의 아미노질소함량은 명태육에서 $8{\sim}14$배, 콩을 첨가한 경우는 $4{\sim}6$배 증가하였고, soluble solid는 각 $2{\sim}3$배와 $2.6{\sim}3$배, 증가하여 상당한 단백질 분해양상을 보였다. 핵산관련물질 중 아미노산과 함께 맛의 상승효과를 주는 IMP, GMP는 control보다 증가되었으며, 발효된 명태육의 총 유리아미노산 함량은 명태육만을 사용한 경우 $5{\sim}14$배 증가하여 Aspergillus oryzae KFCC 32343에서 4,326 mg%(DB)로 가장 높았고, 콩을 첨가한 경우도 Aspergillus oryzae KFCC 32343에서 6,362 mg%(DB)로 가장 높았다. 아미노산 조성은 균주에 따라 다소 차이가 있지만, 양적으로 많은 아미노산은 Glu, His, Asp, Lys 순이었다. 발효된 명태추출액을 멸치국물과 비교하여 관능검사한 결과 냄새, 맛, 종합적인 기호도에서 별치국물보다 우수하였고, 모든 결과를 평가해 볼 때, Aspergillus oryzae KFCC 32343을 이용하여 명태어육으로부터 풍미물질 생산이 가능하였다.

• 유기물자원화
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• 제8권4호
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• pp.147-152
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• 2000

남은 음식물을 기질로 생균효모사료를 만들기 위해 Kluyveromyces marxianus 효모의 호기적 액상발효가 $35^{\circ}C$에서 시도되었다. 먼저 액상으로 시료를 충분히 마쇄시킨 시료의 효모 생균수를 증가시키기 위한 적정발효조건이 진탕배양을 통해 연구되었다. 시료로 사용된 남은 음식물의 고형분 함량을 수분첨가로 5%, 10%와 15%로 다르게 조정하여 발효시킨 결과 고형분 함량 10%에서 생균수가 가장 높은 것으로 나타났다. 효모의 생균농도를 증가시키기 위하여 Aspersillus oryzae를 2리터용 jar fermenter를 이용하여 혼합배양한 결과 증식속도를 증가시켜 주었으나 최고 생균수는 $3.5{\times}10^9/ml$로서 단독 배양시보다 근소하게 높은 결과를 보여주었다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권4호
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• pp.521-529
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• 2010

Two experiments were conducted to evaluate multi-microbe submerged liquid (SLF) and solid substrate (SSF) fermented probiotic products in broilers. The SLF and SSF probiotics were comprised of Lactobacillus acidophilus ($1.1{\times}10^9$ and $4{\times}10^8$ cfu/g), Bacillus subtilis ($1.1{\times}10^9$ and $4{\times}10^9$ cfu/g), Saccharomyces cerevisiae ($1.5{\times}10^7$ and $1.0{\times}10^4$ cfu/g) and Aspergillus oryzae ($2.6{\times}10^7$ and $4.3{\times}10^7$ cfu/g), respectively. In Exp. 1, 640 day-old Ross chicks were allotted to 4 treatments, each comprising 4 replicates (40 chicks/replicate). The basal diet was prepared without any antimicrobials (negative control, NC), and 20 mg/kg avilamycin (positive control, PC), 0.3% SLF and 0.3% SSF probiotics were added to the basal diets as treatments. Birds fed PC and SSF diets showed improved (p<0.001) overall weight gain and F/G than birds fed NC and SLF diets; whereas, birds fed SLF diet had better weight gain and F/G than birds fed NC diet. Retention of CP was higher (p<0.05) in birds fed the SSF diet than birds fed PC, SLF and NC diets. Birds fed the SLF diet tended to have higher (p<0.10) cecal total anaerobic bacteria than birds fed PC and NC diets; whereas, lesser cecal coliforms were noticed in birds fed PC, SLF and SSF diets than birds fed the NC diet. In Exp. 2, 640 day-old Ross chicks were randomly allotted to 4 treatments in a $2{\times}2$ factorial arrangement. Each treatment had 4 replicates (40 chicks/replicate). Two different multi-microbe probiotic products (0.3% SLF or SSF) each with two different antibiotics (10 mg/kg colistin, or 20 mg/kg avilamycin) were used as dietary treatments. Birds fed the SSF diet had greater weight gain (p<0.001), better F/G (p<0.05), greater retention of energy (p<0.001) and protein (p<0.05), and lesser cecal Clostridium (d 35) than birds fed SLF diet. Birds fed the colistin-supplemented diet had less (p<0.01) cecal coliforms when compared with birds fed the avilamycin diet. Additionally, birds fed the avilamycin diet had greater energy retention (p<0.05) than birds fed the colistin diet. Thus, the results of this study suggest the multi-microbe probiotic product prepared by a solid substrate fermentation method to be superior to the probiotic product prepared by submerged liquid fermentation; moreover, feeding of probiotics with different antibiotics did not elicit any interaction effect between probiotic and antibiotic.

• Journal of Microbiology and Biotechnology
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• 제24권10호
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• pp.1427-1437
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• 2014

Enzymatic hydrolysis of lignocellulosic biomass into fermentable sugars is a key step in the conversion of agricultural by-products to biofuels and value-added chemicals. Utilization of a robust microorganism for on-site production of biomass-degrading enzymes has gained increasing interest as an economical approach for supplying enzymes to biorefinery processes. In this study, production of multi-polysaccharide-degrading enzymes from Aspergillus aculeatus BCC199 by solid-state fermentation was improved through the statistical design approach. Among the operational parameters, yeast extract and soybean meal as well as the nonionic surfactant Tween 20 and initial pH were found as key parameters for maximizing production of cellulolytic and hemicellulolytic enzymes. Under the optimized condition, the production of FPase, endoglucanase, ${\beta}$-glucosidase, xylanase, and ${\beta}$-xylosidase was achieved at 23, 663, 88, 1,633, and 90 units/g of dry substrate, respectively. The multi-enzyme extract was highly efficient in the saccharification of alkaline-pretreated rice straw, corn cob, and corn stover. In comparison with commercial cellulase preparations, the BCC199 enzyme mixture was able to produce remarkable yields of glucose and xylose, as it contained higher relative activities of ${\beta}$-glucosidase and core hemicellulases (xylanase and ${\beta}$-xylosidase). These results suggested that the crude enzyme extract from A. aculeatus BCC199 possesses balanced cellulolytic and xylanolytic activities required for the efficient saccharification of lignocellulosic biomass feedstocks, and supplementation of external ${\beta}$-glucosidase or xylanase was dispensable. The work thus demonstrates the high potential of A. aculeatus BCC199 as a promising producer of lignocellulose-degrading enzymes for the biomass conversion industry.

• 한국축산시설환경학회지
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• 제6권2호
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• pp.73-81
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• 2000

A two-phase anaerobic digestion system for the treatment of swine waste was constructed in a commercial hog farm. The digester system was composed of 4 major units; slurry storage pit, acidogenic digester, methanogenic digester and sedimentation pit. A biogas boiler unit was also attached to maintain the digester temperature of 37$^{\circ}C$. Substrate lading was made with 2hr-interval by pumping about 2.1$m^3$ of slurry type swine waste from the slurry pit into the acidogenic digester, which corresponds to hydraulic retention time of 4 days for the acidogenic digester and of 11 days for the methanogenic digester. Digester temperature were well maintained as the set temperature of 37$^{\circ}C$ in the methanogenic digester, while the temperature in the acidogenic digester showed around 34$^{\circ}C$. pH also showed a steady-state results of 7.3 in the acidogenic digester and of 7.6 in the methanogenic digester during the operation period. Average biogas production rate was 0.66$m^3$/$m^3$ digester volume. Reduction rate of total solid and volatile solid were 42.8% and 5.8%, respectively. Total nitrogen and ammonia nitrogen were not reduced during the anaerobic fermentation, however, most of VFAs seemed to be converted to the biogas,. These fermentation performance data may suggest that he newly developed a two-phase anaerobic digester for the swine waste treatment worked so successfully.

• 한국미생물·생명공학회지
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• 제17권5호
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• pp.510-518
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• 1989

농산 폐자원 중에서도 감귤 가공공정에 따라 부생되는 감귤과피를 발효 기질로서의 이용을 목적으로 분리균 Asp. niger를 사용하여 구연산 발효에 미치는 배양조건 및 영향인자를 조사하였다. 그 결과 고 체 배양에서의 최적조건 즉 감귤과피와 물을 동량 혼합하고 여기에 NH$_4$NO$_3$0.2%, MgSO$_4$7$H_2O$ 0.1%, Methanol 2.5%를 첨가하여 PH4.5로 조절한 다음포자 현탁액(1x$10^8$ spore/$m\ell$) 2%를 접종하여 균체증식 초기에 35$^{\circ}C$, 20시간 배양하고 4시간 저온 처리한 다음 구연산 생성기에서 3$0^{\circ}C$로 48시간 배양했을 때 당에 대해 80.4%의 높은 수율의 구연산을 얻었다.

• 유기물자원화
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• 제9권4호
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• pp.99-104
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• 2001

곱게 갈아 액화시킨 음식물 찌꺼기를 기질로 생균사료를 생산하기 위한 효모의 호기적 액상발효에 있어서 효모증식에 대한 교반속도의 영향을 연구하였다. screening을 통해 선택한 효모인 Kluyvermyces marxianus를 종균으로 2liter jar fermenter를 이용하여 호기적 조건에서 곱게 분쇄해 10% 고형분 함량을 갖는 기질에 교반속도를 500rpm, 900rpm, 1200rpm를 다르게 조정하여 $35^{\circ}C$에서 증식시켰다. 효모의 증식을 촉진시키기 위하여 고분자물질을 분해하는 효소를 분비하는 곰팡이 Aspergillus oryzae와 혼합발효를 실시하여 단독발효와 비교하였다. 발효결과 교반속도가 증가할수록 생균수도 높아져 400rpm에서보다는 900rpm에서 높은 생균수를 보였으나 1200rpm에서는 오히려 감소하였다. 혼합발효는 amylase의 역가를 높여주어 증식속도를 높여 주나 발효종료단계에서 최고 생균수를 증가시켜주지는 않는 것으로 나타났다.