• Journal of Microbiology and Biotechnology
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• 제23권12호
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• pp.1654-1663
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• 2013

Rice straw is closely associated with meju fermentation and it is generally known that the rice straw provides meju with many kinds of microorganisms. In order to elucidate the origin of meju fungi, the fungal diversity of rice straw was examined. Rice straw was collected from 12 Jang factories where meju are produced, and were incubated under nine different conditions by altering the media (MEA, DRBC, and DG18), and temperature ($15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$). In total, 937 strains were isolated and identified as belonging to 39 genera and 103 species. Among these, Aspergillus, Cladosporium, Eurotium, Fusarium, and Penicillium were the dominant genera. Fusarium asiaticum (56.3%), Cladosporium cladosporioides (48.6%), Aspergillus tubingensis (37.5%), A. oryzae (31.9%), Eurotium repens (27.1%), and E. chevalieri (25.0%) were frequently isolated from the rice straw obtained from many factories. Twelve genera and 40 species of fungi that were isolated in the rice straw in this study were also isolated from meju. Specifically, A. oryzae, C. cladosporioides, E. chevalieri, E. repens, F. asiaticum, and Penicillium polonicum (11.8%), which are abundant species in meju, were also isolated frequently from rice straw. C. cladosporioides, F. asiaticum, and P. polonicum, which are abundant in the low temperature fermentation process of meju fermentation, were frequently isolated from rice straw incubated at $15^{\circ}C$ and $25^{\circ}C$, whereas A. oryzae, E. repens, and E. chevalieri, which are abundant in the high temperature fermentation process of meju fermentation, were frequently isolated from rice straw incubated at $25^{\circ}C$ and $35^{\circ}C$. This suggests that the mycobiota of rice straw has a large influence in the mycobiota of meju. The influence of fungi on the rice straw as feed and silage for livestock, and as plant pathogens for rice, are discussed as well.

• 한국환경농학회지
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• 제31권2호
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• pp.192-199
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• 2012

유전자변형 작물을 종자로 판매하거나 식품, 사료 혹은 가공용으로 이용하기 위해서는 반드시 관련 기관의 승인을 받아야 한다. 관련부처에서는 유전자변형 작물의 승인에 앞서 환경위해성 평가 자료가 과학적으로 타당한지 검토한다. 환경위해성 평가 중 유전자변형 작물이 토양 미생물 군집에 미치는 영향은 충분히 연구되지 못한 분야이다. 최근 토양 환경내 미생물 군집의 특성을 연구하기 위한 발전된 방법들이 개발되고 있다. 배양에 의존적인 또는 비의존적인 기술에 의한 토양 미생물의 군집 특성을 조사한 연구와 유전자변형 작물의 환경위해성 평가 적용 가능성을 고찰하였다. 유전자변형 작물의 토양미생물 영향 평가는 사안별 평가 원칙에 의해 이루어져야 한다. 신뢰할 수 있고 상세한 토양 미생물 평가가 이루어지기 위해서는 다양한 분석 방법의 조합이 필요하다.

• 한국수산과학회지
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• 제32권2호
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• pp.144-148
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• 1999

상업적 규모의 순환여과식 탱크에서 사료 공급 횟수에 따른 산소 소비량의 변화를 조사하였다. 실험에 이용된 사육 장치는 순환여과식 시설내의 원형 콘크리트 탱크 (직경 270cm, 높이 80cm)를 이용하여 평균 체중 400g의 나일틸라피아 (Oreochromis niloticus)를 390kg 방양하여 실험에 이용하였다. 우선 3일간 사육 어류를 절식시킨 후 기초대사율을 측정하였고, 사료 공급 횟수를 1회, 2회, 5회 그리고 9회로 나누어 공급한 후 산소 소비량의 일간 변화를 측정하였다. 절식 상태에서 산소 소비량 (기초대사율)은 평균 $39.31{\pm}4.4mg\;O_2/kg$ fish/hr이였고 사료 공급횟수에 따른 1일 평균 산소 소비량은 1회, 2회, 5회 및 9회 공급시 각각 $79.9{\pm}21.5,\;81.3{\pm}14.8,\;84.2{\pm}9.9$ 및 $98.9{\pm}11.0mg\;O_2/kg$ fish/hr을 소비하는 것으로 나타나 사료 공급 횟수가 증가함에 따라 평균 산소 소비량은 증가하였으나, 유의적인 차이는 나타나지 않았다. 사료 공급후 최대 산소 소비량에 도달하는 시간은 사료 공급후 30$\~$50분으로 나타나 사료공급 횟수와는 유의적인 상관 관계가 없는 것으로 나타났다. 사료공급 횟수에 따른 산소 소비량의 최대치는 1회, 2회, 5회 및 9회 공급시에 각각 161.2, 123.4, 111.1 및 111.1 mg $O_2/kg$ fish/hr을 소비하는 것으로 나타나 하루에 1회 공급하였을 때 최대 산소 소비량이 가장 높은 것으로 나타났다.

• Fisheries and Aquatic Sciences
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• 제5권1호
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• pp.59-63
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• 2002

Swim up fry of the Nile tilapia, Oreochromis niloticus, were fed 0 or 60 mg l7-methyltestos­terone (MT) per kg feed for 30 days. Fish that had been fed 0 or 60 ppm MT for the first 30 days were subsequently fed a commercial diet for 56 weeks to evaluate growth, survival, sex ratio, body composition, gonadosomatic index and the total edible portion. Mean body weight of MT treated group and untreated group were 1.7 g and 1.1 g, respectively at the end of the treatment for 30 days $(P<0.05)$. The experiment was terminated after a total of 60 weeks, the mean body weight of the MT treated population was 1,016 g and that of the untreated population was 762g $(P<0.05)$. However, the final mean body weight of untreated males (l, 086g) was not significantly different from treated males (l,016 g), but the mean body weight of the female group was 512 g. Therefore, the reason for the lower mean body weight of the untreated group was entirely due to stunted females. The percentage fillet yield of MT treated fish$(34.6\%)$ was not significantly different from that of the untreated males $(34.4\%)$, but the untreated females were lower than those of both treated and untreated male groups $(32.4\%)$ (P<0.05). There were no significant differences in the percentage of the all edible portion (AP) between MT treated and untreated males, but females were lower than males. Females are smaller fish in size and the gonads are larger in proportion which were discarded along with the intestine this explains the observed difference. Total biomass of the two groups were 134.8kg and 104.5kg per $m^3$, respectively. The proportion of fish reaching a marketable size of over 800 g in body weight within 14 months were $78\%$ in the MT treated group and $41\%$ in the untreated group.

• 한국버섯학회지
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• 제9권4호
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• pp.166-169
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• 2011

느타리버섯 수확후 배지의 가축사료화가 가능하도록 주재료로 콘코브를 사용하여 적합한 영양원을 선발하고자 하였다. 시험에 사용된 영양원 가운데 질소함량은 채종박(7.6%)>케이폭박(6.4%)>밀기울(2.7%)순이고, 조지방함량은 밀기울(2.7%)>케이폭박(2.4%)>채종박(1.3%)>면실박(0.8%)로 나타났다. 영양원별 혼합배지의 이화학적 특성결과 C/N율은 18~20, 용적밀도 $0.27{\sim}0.28g/cm^3$, 공극률 73.1~74.8로 처리간의 차이가 없었으며, 병당 수량은 케이폭박 첨가구(케이폭박 단용, 면실박+케이폭박(1:1) 혼용, 케이폭박+밀기울(1:1) 혼용)가 153~158g으로 대조구(면실박, 150g)와 차이가 없는 것으로 나타났고, 그러나 채종유박은 초발이 소요일수도 1일 늦고 수량도 상대적으로 낮은 것으로 나타났다. 케이폭박 처리구의 수확후 배지의 사료적 가치를 분석결과 58.3%로 면실박보다 높은것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권10호
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• pp.1381-1388
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• 2012

An in vitro experiment was conducted to examine the effects of defaunation (removal of protozoa) on ruminal fermentation characteristics, $CH_4$ production and degradation by rumen microbes when incubated with cereal grains (corn, wheat and rye). Sodium lauryl sulfate as a defaunation reagent was added into the culture solution at a concentration of 0.000375 g/ml, and incubated anaerobically for up to 12 h at $39^{\circ}C$. Following defaunation, live protozoa in the culture solution were rarely observed by microscopic examination. A difference in pH was found among grains regardless of defaunation at all incubation times (p<0.01 to 0.001). Defaunation significantly decreased pH at 12 h (p<0.05) when rumen fluid was incubated with grains. Ammonia-N concentration was increased by defaunation for all grains at 6 h (p<0.05) and 12 h (p<0.05) incubation times. Total VFA concentration was increased by defaunation at 6 h (p<0.05) and 12 h (p<0.01) for all grains. Meanwhile, defaunation decreased acetate and butyrate proportions at 6 h (p<0.05, p<0.01) and 12 h (p<0.01, p<0.001), but increased the propionate proportion at 3 h, 6 h and 12 h incubation (p<0.01 to 0.001) for all grains. Defaunation increased in vitro effective degradability of DM (p<0.05). Production of total gas and $CO_2$ was decreased by defaunation for all grains at 1 h (p<0.05, p<0.05) and then increased at 6 h (p<0.05, p<0.05) and 12 h (p<0.05, p<0.05). $CH_4$ production was higher from faunation than from defaunation at all incubation times (p<0.05).

• 수산경영론집
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• 제45권1호
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• pp.95-107
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• 2014

This study is aimed to analyze the economic performance of black rockfish aquaculture by standardizing cost structures by region and farming size. The result of survey on farming and sale condition in each region, stocking density, survival rate, juvenile price, and unit production was the highest at Yeosu and Tongyeong, Heuksando showed the lowest. While rearing period was the longest at Tongyeong, the shortest region was Yeosu and Wando. In farming cost structure by region, amount of feeing was the highest at Tongyeong and Yeosu, and the lowest was Heuksando. Cost of medicine was high in Wando and Taean region, Yeosu and Hecksando was low. In case of farm size, feed cost ratio was high in the order of medium(0.75ha), small(0.25ha) and large(1.25ha) size. Standard production cost at every farm size of Heuksando showed the lowest among these regions. Taean and Yeosu was middle, and Tongyeong and Wando was the highest. According to the income, profit rate and investment return of farm size in all regions, as the bigger farm size, the higher income and profit rate was revealed. However, in case of Wando, Taean, and Heuksando which regions has high investment return, medium farm size was higher than large size. The result of economic analysis according to various factors, economic feasibility of black rockfish aquaculture in marine floating cage was showed significant changes by rearing and market condition.

• 유기물자원화
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• 제23권1호
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• pp.38-44
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• 2015

본 연구에서는 저온 해양성 미세조류인 Nannochloropsis sp.를 대상으로 (주)아이엠비즈에서 개발한 수직형 고효율 광배양기를 통한 생산성 평가를 목적으로 2톤의 배양액으로 자가영양의 옥외생장실험을 진행하였다. 한달간 진행된 실험에서, 0.1%의 $CO_2$를 주입한 배양에서는 일평균 0.953g/L의 생산성을 나타냈으며, 공기만을 주입했을 경우에는 0.574g/L의 생산성을 나타냈다. 온도의 분포는 최저 $20^{\circ}C$에서 최고 $31^{\circ}C$에 이르렀으며, 이 범위에서 온도에 따른 생산성의 변화는 크게 차이가 없는 것으로 나타났다. 빛의 세기는 최저 5,000럭스에서 최고 4만 럭스 내외로 조사되었으며, 빛의 세기와 미세조류의 생장사이에 매우 밀접한 관련이 있는 것으로 밝혀졌다. 한편, 본 실험에서 시도된 개발된 배양기를 통한 가압부상에 의한 조류의 수확방법은 효과가 매우 높은 것으로 나타났다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권1호
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• pp.17-22
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• 2004

A bacterial strain WJ-98 found to produce active extracellular keratinase was isolated from the soil of a poultry factory. It was identified as Paracoccus sp. based on its 16S rRNA sequence analysis, morphological and physiological characteristics. The optimal culture conditions for the production of keratinase by Paracoccus sp. WJ-98 were investigated. The optimal medium composition for keratinase production was determined to be 1.0% keratin, 0.05% urea and NaCl, 0.03% K$_2$HPO$_4$, 0.04% KH$_2$PO$_4$, and 0.01% MgCl$_2$$.$6H$_2$O. Optimal initial pH and temperature for the production of keratinase were 7.5 and 37$^{\circ}C$, respectively. The maximum keratinase production of 90 U/mL was reached after 84 h of cultivation under the optimal culturing conditions. The keratinase from Paracoccus sp. WJ-98 was partially purified from a culture broth by using ammonium sulfate precipitation, ion-exchange chromatography on DEAE-cellulose, followed by gel filtration chromatography on Sephadex G-75. Optimum pH and temperature for the enzyme reaction were pH 6.8 and 50$^{\circ}C$, respectively and the enzymes were stable in the pH range from 6.0 to 8.0 and below 50$^{\circ}C$. The enzyme activity was significantly inhibited by EDTA, Zn$\^$2+/ and Hg$\^$2+/. Inquiry into the characteristics of keratinase production from these bacteria may yield useful agricultural feed processing applications.

• Food Quality and Culture
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• 제1권1호
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• pp.46-57
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• 2007

The purpose of the present study was to examine the nutrient intake status of elderly dementia patients. We surveyed the dietary intake of 50 demented elderly patients receiving a regular diet, who were hospitalized in a geriatric hospital in Yongin, Gyeonggi-do. The average age of the subjects was $79.6{\pm}6.5$ for the males and $80.5{\pm}6.3$ for the females. The average heights were $169.5{\pm}6.0\;cm$ (males) and $154.6{\pm}5.2\;cm$ (females), and the average weights were $58.5{\pm}7.4$ (males) and $51.7{\pm}8.9\;kg$ (females). Depending on the type of dementia, the male patients showed significant differences in their intakes of vegetable protein, fiber, total iron, and non-heme iron between the Alzheimer's disease (AD) and the vascular dementia (VD) groups, and the female patients showed significant differences in their intakes of total protein, phosphorus, zinc, and vitamin $B_6$ between the two groups. The male patients showed significant differences in their intakes of animal-source calcium and carotene according to ability to self-feed. According to physical activity, the male patients showed significant differences in vegetable fat and vitamin A intake, and the females showed significant differences in their intakes of total protein, animal protein, fiber, ash, total calcium, vegetable-source calcium, animal-source calcium, phosphorous, total iron, non-heme iron, heme iron, sodium, vitamins $B_1$, $B_2$, $B_6$, niacin, vitamin C, folate, and potassium. We found that the patients consumed excessive protein, but low amounts of calcium, vitamin $B_2$, and folate. Also, the patients' physical activity abilities appeared to affect their nutrient intakes.