• Asian-Australasian Journal of Animal Sciences
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• 제9권4호
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• pp.397-403
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• 1996

Two hundred 10-day-lid, male Arbor Acres broiler chicks divided randomly into 4 groups of 50 chicks each were used. Different feeding treatment was carried out for each group. Chicks in treatment 1 were fed a basal diet(Starter feed)(control); treatment 2, a basal diet + 0.1% B. subtilis culture; treatment 3, a basal diet + 0.2% lactobacilli culture in the feed; and treatment 4, a basal diet + 5 g lactobacilli in the drinking water. The viable bacterial counts for each treatment were approximately $10^9cells/kg$ feed. The weight gain in chickens given feeds incorporated with B. subtilis and lactobacilli was significantly(p < 0.05) higher than those of the control. With regard to feed efficiency, there was a definite tendency towards a higher feed : gain lower(p < 0.05) feed : gain ratio. A significantly(p < 0.05) larger population of Lactobacillus was found in the small intestine of chickens fed with feed incorporated with B. subtilis at 21 and 28 days and with lactobacilli at 14, 21 and 28 days. Populations of intestinal E. coli in broilers given feed added with B. subtilis were not significantly(p < 0.05) different from those of the control, but in chickens fed lactobacilli-added feed, their populations wee significantly lower(p < 0.05) at 14 and 21 days. No significant differences were found among the treatments and the control in the occurrence of Salmonella and Campylobacter during the whole experimental period.

• Asian-Australasian Journal of Animal Sciences
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• 제11권4호
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• pp.351-362
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• 1998

Microbial growth efficiency in the rumen was studied in sheep given hourly, 31.25 g oaten chaff with either 0.31 and 0.88 g urea or 1.88 and 5.63 g casein (exp. 1) and 33.33 g oaten chaff with 1.04 casein or 0.3, 0.6 and 0.9 g urea or the mixture of the casein and urea (exp. 2). Concentrations of ruminal fluid ammonia increased with increasing nitrogenous supplements. Organic matter digestibility in sacco in the rumen was not different irrespective of N sources. Isoacids and valeric acid increased with increasing ingested casein but decreased with increasing urea intake. Peptide and amino acid pools in ruminal fluid increased with increasing ammonia concentrations (exp. 2) suggesting that proteolytic activity and transportation of peptides and amino acids across microbial membrane of rumen microbes may be regulated by the metabolite mechanism (intracellular amino acids and $NH_4{^+}$, respectively). Densities of total viable and cellulolytic bacteria in ruminal fluid increased with increasing ammonia levels but that of small Entodinia decreased. The density of fungal sporangia growth on oat leaf blades decreased with increasing ammonia concentrations but appeared to remain constant in the presence of casein. Efficiency of net microbial cell synthesis was 15-28% higher when ammonia concentrations increased from 100 to above 200 mg N/l regardless of N sources. In conclusion, supplementation of preformed protein had no effect on rumen digestion and microbial growth efficiency. This could not be accounted for its effect on ruminal fluid ammonia. Increased microbial growth efficiency with increasing ammonia levels may be due to a reduction in the turnover of microbial cells within the rumen.

• 한국식품조리과학회지
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• 제32권5호
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• pp.585-592
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• 2016

Purpose: The purpose of this study was to investigate the quality characteristics and antioxidant activity on consequent storage based on the temperature of new cultivar dew-drop pine mushroom (Lentinula edodes GNA01). Methods: Dewdrop Pine Mushroom were prepared under different storeage temperature (4, 10, $20^{\circ}C$). Results: Weight loss and hardness showed the least reduction rate when it was stored at $4^{\circ}C$ (p<0.05). The color value changed to dark brown at all storage temperatures during the storage period. When it was stored at $4^{\circ}C$, it maintained its initial color for a longer period than at different storage temperatures. With respect to the change in its viable cell count, the cells proliferated to less than 3.0 log CFU/g up to Ed: Please review the change. The earlier part was difficult to understand 2.83 log CFU/g until 15 days of storage at $4^{\circ}C$. On measuring the antioxidant activity of this mushroom, the polyphenol content was maintained without a large change until 9 days of storage at $4^{\circ}C$. The electron-donating action maintained high antioxidant activity, accounting for 81.99% until 12 days of storage from 83.08% during the initial storage at $4^{\circ}C$. When it was stored at $4^{\circ}C$, the sensory characteristics received the highest score among all items, such as appeaance, color, flavor and general preference, etc. Concolusion: In summary, new Cultivar Dewdrop Pine Mushroom (Lentinula edodes GNA01) can maintain its commercial value until the 12th day of $4^{\circ}C$ storage.

• 한국조리학회지
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• 제12권2호
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• pp.195-205
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• 2006

복분자 착즙액을 첨가한 호상 요구르트를 제조하기 위하여 skim milk에 S. thermophilus, L. acidophilus와 L. casei를 혼합한 균주를 접종하여 복분자 착즙액이 요구르트의 품질 특성에 미치는 영향을 조사하였다. pH는 전반적으로 발효기간중 감소하는 경향을, 산도는 증가하는 경향을 나타냈다. 생균수 변화에 있어서 복분자 착즙액의 첨가는 농도에 따라 생육을 촉진하기도 하고 저해하기도 하는 것으로 나타났으나, 4% 첨가농도까지는 안정된 발효를 유도하는 결과를 보였다. 성분 분석 결과를 살펴보면, 대조구와 복분자 착즙액 첨가구별 단백질, 유당, 유리지방산 함량에서는 시료간 비슷한 값을 보였고, 복분자 착즙액의 첨가량에 따라 총고형분함량은 증가하였다. 기호도 검사에서는 3% 복분자즙 첨가구가 색, 향, 맛, 후미 및 종합적인 기호도에서 가장 높은 선호도를 나타내었다.

• 한국축산식품학회지
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• 제24권2호
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• pp.164-170
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• 2004

건강한 성인의 분변으로부터 담즙산 분해능이 우수한 젖산균의 분리를 위하여 무작위 선별법과 도말법을 사용하여 층 120주의 젖산균을 1차 분리하였고, 그중 5종의 젖산균을 최종 선발하였다. 유용한 젖산균이 갖추어야할 중요한 성질인 내산성, 내담즙산성, 대장균 저해능을 시험한 결과 Lactobacillus sp. CK 102이 가장 우수한 균주로 나타났다. Lactobacillus sp. CK 102 균주는 pH 2.0에서 68％ 이상의 내성과 1.0％ 담즙산이 함유된 배지에서 90％이상의 내성을 나타냈으며 MRS 배지에서 대장균과 혼합 배양시 18시간 이내에 대장균을 100％ 사멸시켰다. 젖산균제로써 기능이 가장 우수한 균주인 Lactobacillus sp. CK 102를 API kit와 16S rRNA sequencing 방법을 사용하여 동정한 결과 Lactobacillus platarum 으로 밝혀졌다. 이상의 결과에서 분리한 Lactobacillus sp. CK 102는 생균제로서 안전하게 이용할 수 있는 것으로 나타났다.

• ALGAE
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• 제26권2호
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• pp.181-192
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• 2011

Ballasting and deballasting of shipping vessels in foreign ports have been reported worldwide as a vector of introduction of non-native aquatic plants and animals. Recently, attention has turned to ballast water as a factor in the global increase of harmful algal blooms (HABs). Many species of microalgae, including harmful dinoflagellate species, can remain viable for months in dormant benthic stages (cysts) in ballast sediments. Over a period of four years, we surveyed ballast water and sediment of ships docked in two ports of Tampa Bay, Florida, USA. Sampling conditions encountered while sampling ballast water and sediments were vastly different between vessels. Since no single sample collection protocol could be applied, existing methods for sampling ballast were modified and new methods created to reduce time and labor necessary for the collection of high-quality, qualitative samples. Five methods were refined or developed, including one that allowed for a directed intake of water and sediments. From 63 samples, 1,633 dinoflagellate cysts and cyst-like cells were recovered. A native, cyst-forming, harmful dinoflagellate, Alexandrium balechii (Steidinger) F. J. R. Taylor, was collected, isolated, and cultured from the same vessel six months apart, indicating that ships exchanging ballast water in Tampa Bay have the potential to transport HAB species to other ports with similar ecologies, exposing them to non-native, potentially toxic blooms.

• 미생물학회지
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• 제22권1호
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• pp.1-18
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• 1984

1976年 3月부터 1977年 2月까지 滿 12個月동안 榮山江 汽水域 39個 場所로부터 採水한 156個 water sample로서 酵母의 季節的 分布와 度包配에 따른 이들 酵母의 分布型을 調査하였다. 酵母의 全體 平均値는 100ml당 52에서 487個의 生菌數를 보여주었고 가장 많은 個體數는 春季에 있었고 가장 적은 個體數는 夏季에 있었다. 14屬 83種에 해당하는 933個의 酵母와 한 種의 酵母樣 곰팡이가 分離되었는데 基中 Candida가 29%, Debaryomyces가 17.3%, Rhodotorula가 16%, Saccharomyces가 14%이었고 나머지 다른 屬들은 10%以內이었다. Debaryomyces hansenii와 Rhodotorula glutinis가 全水域에서는 물론 年中 優點種이었고 총 好氣性細菌集團의 크기, 陸水流入量, 그리고 몇가지 지형적 기후적 요소들이 汽水환경에서 酵母의 季節的 分布는 물론 種의 組成을 反映하는 같다. 酵母의 平均數, 種의 多樣性 特히 醱酵性 및 爲菌系形成 母酵들의 數는 감度가 감소함에 따라 增加한 反面 질산염 利用酵母들은 위와 相反된 경향을 보여주었는데 이는 汽水域에서 酵母의 分布型을 認識하는데 감度勾配가 바람직한 看破 요소로서 利用될 수 ㅣ있음을 시사하고 있다.

• 미생물학회지
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• 제24권2호
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• pp.147-153
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• 1986

나균(M. leprae)을 비롯한 항산균(mycobacterium)의 시험관내 생리력 또는 생명력평가법(in vitro assessment of physiological potential or viability)으로 형광분광측정법(fluorospectrophotometry)를 고안하였다. 균액을 비형광성의 fluorescein diacetate(FDA)로 처리, 균체의 생대사능에 의해 FDA로부터 유리된 체내 fluorescein 량을 Aminco-Bowman 형광분광기로 측정함으로 균체의 생리능을 fluorounit로 표기해 보았다. Fluorounit로 표기된 균체의 생명력을 균배양의 광학밀도(optical density, colony forming unit, 체내 ATP 량 intracellular ATP content)등으로 표기되는 항산균의 생명력고 비교 검토함으로 형광분광법에 의한 시험관내 항산균의 생명력 평가법의 적합성을 살펴보았다. 형광분광측정에 의한 생명도의 평가는 객관성을 띤 기기정량법으로 조작이 간단하고 신속하게 결과를 얻을 수 있어 시험관내 배양의 속도가 완만한 균이나(slow growing mycobacteria, I.e.M. lerpae, Listeriae sp)등의 생명력의 상대적 평가에 활용될 수 있다고 사료된다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 추계학술발표대회
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• pp.35.1-35.1
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• 2011

New photovoltaic (PV) materials and manufacturing approaches are needed for meeting the demand for lower-cost solar cells. The prototypal thin-film photovoltaic absorbers (CdTe and $Cu(In,Ga)Se_2$) can achieve solar conversion efficiencies of up to 20% and are now commercially available, but the presence of toxic (Cd,Se) and expensive elemental components (In, Te) is a real issue as the demand for photovoltaics rapidly increases. To overcome these limitations, there has been substantial interest in developing viable alternative materials, such as $Cu_2ZnSnS_4$ (CZTS) is an emerging solar absorber that is structurally similar to CIGS, but contains only earth abundant, non-toxic elements and has a near optimal direct band gap energy of 1.4~1.6 ev and a large absorption coefficient of ${\sim}10^4\;cm^{-1}$. The CZTS absorber layers are grown and investigated by various fabrication methods, such as thermal evaporation, e-beam evaporation with a post sulfurization, sputtering, non-vacuum sol-gel, pulsed laser, spray-pyrolysis method and electrodeposition technique. In the present work, we report an alternative method for large area deposition of CZTS thin films that is potentially high throughput and inexpensive when used to produce monolithically integrated solar panel modules. Specifically, we have developed an aqueous chemical approach based on chemical bath deposition (CBD) with a subsequent sulfurization heat treatment. Samples produced by our method were analyzed by scanning electron microscopy, X-ray diffraction, transmission electron microscopy, absorbance and photoluminescence. The results show that this inexpensive and relatively benign process produces thin films of CZTS exhibiting uniform composition, kesterite crystal structure, and good optical properties. A preliminary solar cell device was fabricated to demonstrate rectifying and photovoltaic behavior.

• 한국미생물·생명공학회지
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• 제44권3호
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• pp.229-235
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• 2016

우리나라는 예전부터 전통적인 방법으로 누룩을 제조하고, 이를 발효제로 막걸리를 만들어 왔다. 막걸리는 여과 또는 살균 과정없이 다양한 미생물을 살아 있는 상태로 섭취하기 때문에 영양학적으로나 기능적인 측면에서 가치가 높다. 최근 많은 연구에서 막걸리로부터 미생물을 분리동정하고 다양한 기능성에 대해 스크리닝한 결과, 높은 프로바이오틱스 활성과 다양한 스펙트럼의 항균활성을 가진 균주들이 선별되었다. 특히 일부 유산균들은 GABA와 EPS 등의 기능성 물질을 생성하기도 했다. 또한, 일부 유산균과 효모의 경우 각각 bacteriocin 및 killer toxin을 통해 항균활성을 나타내는 것으로 여겨진다. 이러한 막걸리 유래 기능성 미생물과 그 대사산물은 기능성 식품 소재나 안전한 식품첨가물 및 다양한 산업분야에서 활용될 수 있을 것이다.