• Journal of Dairy Science and Biotechnology
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• 제37권2호
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• pp.83-93
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• 2019

Food spoilage by fungi is responsible for considerable food waste and economical losses. Among the food products, fermented dairy products are susceptible to deterioration due to the growth of fungi, which are resistant to low pH and can proliferate at low storage temperatures. For controlling fungal growth in dairy products, potassium sorbate and natamycin are the main preservatives used, and natamycin is approved by most countries for use in cheese surface treatment. However, a strong societal demand for less processed and preservative-free food has emerged. In the dairy products, lactic acid bacteria (LAB) are naturally present or used as cultures and play a key role in the fermentation process. Fermentation is a natural preservation technique that improves food safety, nutritional value, and specific organoleptic features. Production of organic acids is one of the main features of the LAB used for outcompeting organisms that cause spoilage, although other mechanisms such as antifungal peptides obtained from the cleavage of food proteins and competition for nutrients also play a role. More studies for better understanding these mechanisms are required to increase antifungal LAB available in the market.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.226.3-227
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• 2003

Lactic acid bacteria have been considered as the most beneficial probiotic organisms contributing to inhibition of harmful and putrefactive intestinal bacteria. Among them, Bifidobacterium spp. has been considered as one of the most beneficial probiotic organism that can improve the health of humans, since it is one of the major bacteria flora in human intestine. However, the harmful enzyme-inhibitory activity of lactic acid bacteria of Kimchi, which is a representative Korean fermented food has not been evaluated. (omitted)

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.407-408
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• 2001

Stable isotope technique in matrine science is becoming powerful tool to roveal the environmental characteristics surrounding organisms during their past life histories. general, the isotopic data can be used for estimations of habitat temperature, migratory patterns and habitat location, metabolic rates, and investigations of food chains (Kalish, 1991). (omitted)

• Preventive Nutrition and Food Science
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• 제10권3호
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• pp.257-261
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• 2005

Marine sponges are known to produce a number of cytotoxic secondary metabolites. In the course of searching for cytotoxic metabolites from marine organisms, we have evaluated cytotoxic activities of six marine secondary metabolites isolated from various sponges. The cytotoxic compounds 1-6 were isolated by the application of various chromatographic methods, including column chromatography and HPLC. The molecular structures were mostly determined using mass spectrometry (MS) and Nuclear Magnetic Resonance (NMR) Spectroscopy. Furanosestererpenes (compounds 1-3) from Psammocinia sp., cyclitol derivatives (compounds 4 and 5) from Sarcotragus sp., and bromotyrosine-type compound (6) from an association of two sponges Jaspis wondoensis and Poecillastra wondoensis were evaluated for their cytotoxic activity against three cancer cell lines; Hep G2, HeLa, and MCF-7. All tested compounds exhibited cyctoxicity at concentrations ranging from $5\;\mug/mL\;to\;25\;\mug/mL.$ Particularly, among the tested compounds, compound 6 showed the highest potency displaying at least $80\%$ of cytotoxicity at $5\;\mug/mL$ level against all three cancer cell lines.

• 한국식품영양과학회지
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• 제22권3호
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• pp.359-366
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• 1993

Molds are eucaryotic, multicellular, multinucleate, filamentous organisms that reproduce by forming asexual and sexual spores. The spores are readily spread through the air and because they are very light-weight and tend to behave like dust particles, they are easily disseminated on air currents. Molds therefore are ubiquitous organisms that are found everywhere, throughout the environment. The natural habitat of most molds is the soil where they grow on and break down decaying vegetable matter. Thus, where there is decaying organic matter in an area, there are often high numbers of mold spores in the atmosphere of the environment. Molds are common contaminants of plant materials, including grains and seeds, and therefore readily contaminate human foods and animal feeds. Molds can tolerate relatively harsh environments and adapt to more severe stresses than most microorganisms. They require less available moisture for growth than bacteria and yeasts and can grow on substrates containing concentrations of sugar or salt that bacteria can not tolerate. Most molds are highly aerobic, requiring oxygen for growth. Molds grow over a wide temperature range, but few can grow at extremely high temperatures. Molds have simple nutritional requirements, requiring primarily a source of carbon and simple organic nitrogen. Because of this, molds can grow on many foods and feed materials and cause spoilage and deterioration. Some molds ran produce toxic substances known as mycotoxins, which are toxic to humans and animals. Mold growth in foods can be controlled by manipulating factors such as atmosphere, moisture content, water activity, relative humidity and temperature. The presence of other microorganisms tends to restrict mold growth, especially if conditions are favorable for growth of bacteria or yeasts. Certain chemicals in the substrate may also inhibit mold growth. These may be naturally occurring or added for the purpose of preservation. Only a relatively few of the approximately 100,000 different species of fungi are involved in the deterioration of food and agricultural commodities and production of mycotoxins. Deteriorative and toxic mold species are found primarily in the genera Aspergillus, Penicillium, Fusarium, Alternaria, Trichothecium, Trichoderma, Rhizopus, Mucor and Cladosporium. While many molds can be observed as surface growth on foods, they also often occur as internal contaminants of nuts, seeds and grains. Mold deterioration of foods and agricultural commodities is a serious problem world-wide. However, molds also pose hazards to human and animal health in the form of mycotoxins, as infectious agents and as respiratory irritants and allergens. Thus, molds are involved in a number of human and animal diseases with serious implication for health.

• 한국양식학회지
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• 제11권1호
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• pp.99-103
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• 1998

rotifer의 배양조에 혼재된 Artemia가 rotifer의 증식에 미치는 영향을 검토하였다. 실험에는 Koshiki주의 rotifer, Brachionus rotundiformis와 미국 샌프란시스코의 Great Salt lake주의 Artemia sp.를 사용했다. 그리고 모든 실험은 염분을 22ppt, 배양 온도는 $25^{\circ}C.$, 먹이로서 N. oculata을 2일 간격으로 ml 당 $7{\times}10^5$ 세포씩 공급하면서, 50 ml의 비이커에 N. oculata 현탁액을 40ml씩 넣고, rotifer 20마리 그리고 Artemia는 3마리씩 각 수조에 수용하여 각 생물들을 단일종 배양한 경우와 혼합 배양한 경우의 증식을 비교하였다. rotifer와 Artemia 유생을 혼합 배양한 경우, 두 생물은 한정된 먹이 N. oculata 조건하에서 먹이 경쟁(food competition)을 하였다. 또한, rotifer의 대량 배양조에 Artemia 성체의 급속한 섭식 활동에 의해서 심각한 먹이 부족 현상을 일으켰다. 결국, Artemia 성체는 rotifer의 안정적인 생산을 크게 방해하는 rotifer 증식 억제 요인으로서 작용했다. 즉, rotifer을 안정적으로 생산하기 위해서는 종묘 생산 과정에서 유발될 수 있는 Artemia의 혼재가 일어나지 않도록 각별한 주의가 필요하다.

• 농약과학회지
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• 제15권1호
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• pp.48-54
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• 2011

국내 주요 6대 하천수역 내 농약 성수기에 검출된 농약의 검출수준을 조사하였고, 수서 생물 3종(조류, 물벼룩, 어류)의 농약 노출에 따른 위해 기능성을 위해 지수(HQ indexes)에 의해 평가하였다. 총 40지점의 모니터링을 실시한 결과, 검출농약은 살균제isoprothiolane, hexaconazole, 살충제 diazinon, chlorpyrifos, prothiofos, 제초제 alachlor, butachlor, molinate의 총 8종으로 확인되었다. 그 중 isoprothiolane이 67.5%의 높은 빈도로 검출되었고, 그 이외의 농약은 15~37.5% 범위의 검출빈도를 나타내었다. 검출빈도는 butachlor >, prothiofos >, ch1orpyrifos >, hexaconazole, molinate > diazinon, alachlor순으로 조사되었다. 전 하천수역에서 수서 생물 3종(조류, 물벼룩, 어류)에 대한 위해 지수가 1.0을 초과하지 않았기 때문에 수 생태계에 대한 위해 가능성이 없는 것으로 평가되었다. 주요 하천수역 내 수서 생물의 위해 가능성에 대한 각 검출 농약의 상대적인 기여도를 평가한 결과, 수서 생물 종별로 다양하게 나타났다. 조류는 butachlor와 molinate성분에 의해, 물벼룩은 chlorpyrifos, diazinon, prothiofos 성분에 의해, 어류는 chlorpyrifos성분에 의해 위해 지수의 기여도가 높게 조사되었다. 본 연구결과는 하천 수계별 농약관리의 우선순위를 선정하는 데 있어 필수자료로 활용될 수 있을 것으로 사료된다.

• 한국수산과학회지
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• 제32권4호
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• pp.466-469
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• 1999

전세계의 담수역에 널리 분포하는 Daphnia나 Moins와 같은 담수산 물벼룩은 잉어, 붕어, 금붕어와 같은 담수어의 종묘 생산과정에서 먹이 생물로서 널라 이용되고 있다. 그러나, 해산어의 종묘 생산 과정에서는 안정 배양, 대량 배양이 어렵다는 이유로 로티퍼나 알테미아 이외에 널리 이용되는 먹이 생물은 거의 없다. 이 연구에서는 해산 물벼룩보다는 비교적 배양이 용이한 기수산물벼룩 D. celebensis의 배양 용기의 크기가 안정배양에 미치는 영향을 검토하였다. 종 보존 배양 수준의 40ml 배양에서는 16일간의 배양 기간중 14일째에 최고 밀도가 3.416$\pm$0.396 ind./ml에 달하였다 1,500ml와 15,000ml의 준 대량 배양에서는 각각 배양 개시후 12일째와 21일 째에 14.2$\pm$2.122 ind./ml와 2.489$\pm$1.618 ind./ml의 최고 밀도가 관찰되었다. 그리고 실험 기간중 배양의 안정도를 평가하기 위하여 실시한 세가지 배양 수량간 상대적 개체군 증식 지수 (RPGI)의 비교 결과에서는 1,500ml의 배양 용기에서 가장 안정적인 증식양상을 보였다. 뿐만 아니라, 매일 수확 가능한 기수산 물벼룩 D. celebensis의 개체수를 계산한 결과에서도 (possible harvesting number/ind./ml/day) 1,500ml의 배양 용기에서 가장 높은 3.567$\pm$0.607ind./ml/day가 수확 가능하였다. 한때 필요성에 의하여 담수산 물벼룩을 해산어의 종묘생산 과정에서 먹이생물로 이용한 시기가 있었다. 그러나, 앞으로는 기수산 물벼룩을 해수에서 배양하여 해산 자치어의 먹이생물로 이용할 수 있을 것이다.

• 한국식생활문화학회지
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• 제22권4호
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• pp.454-461
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• 2007

본 연구 결과 동결건조된 감귤과피 70% 메탄올 추출물의 총 폴리페놀 함량은 836.8 ㎎%였으며 감귤과피 추출물 0.01, 0.02와 0.1%의 EDA는 각각 89.6, 86, 81.3%로 높았으며 아질산염 소거능은 pH 1.2에서 34.4%, pH 7.0에서 19.5%를 나타내어 산성 영역에서 높은 소거작용을 보였다. 또한 이들 추출물의 항산화효과는 옥배유의 경우 TBHQ > BHT > TOC > ChEx > EaEx > EtEx > WaEx > Control 순이었고, 채종유의 경우 TBHQ > ChEx > EaEx > BHT > EtEx > WaEx > TOC > Control 순이었다. 두 유지모두에서 에틸아세이트추출물(EaEx)과 클로로포름추출물(ChEx)이 에탄올추출물(EtEx)과 물추출물(WaEx) 보다 항산화 효과가 높았으며 첨가농도가 증가함에 따라 항산화 효과도 증가하는 경향을 보였다. 그리고 감귤과피의 각 용매별 추출물의 공액이중산가도 에틸아세테이트추출물(EaEx)과 클로로포름추출물(ChEx)이 높았으며 이들의 항산화 효과는 TBHQ보다는 낮았으나 BHT, tocopherol과 비교하였을 때 거의 유사하거나 좀 더 높은 경향을 보였다. 한편 감귤과피 추출물은 우수한 항균력을 보여주었고 농도가 상승함에 따라 항균효과도 상승하였으며 이 효과는 그램 양성, 음성균주에서 고르게 나타나 천연 항균소재로서의 이용가능성을 확인하였다. 이상의 결과에서 감귤 과피는 총 폴리페놀 함량과 전자공여능 활성이 높아 항산화효과와 항균효과가 우수하게 나타나 감귤 과피의 기능성 이용도가 매우 높을 것으로 생각되며 감귤 가공 후 생기는 부산물들의 식품산업에서의 유용성도 높을 것으로 사료된다.

• 한국초등과학교육학회지:초등과학교육
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• 제17권2호
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• pp.79-90
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• 1998

The purpose of this study is to investigate degree of the concept formation on cell in elementary school teachers and to clarify the patterns of their misconceptions. Data were collected by interview with 120 elementary school teachers, ranged from twenties to fifties in age, working in Taegu city. The instrument was developed by researchers and was categorized into four: cell as the basic units of life, morphology of cell, function of cell, growth of individual from the viewpoint of cell. The results are as follows: First, about 80% of teachers had two perspective outcome of cell: Cells are the basic units of life on earth. But the potato and meat, which we used to eat as food, are not constructed of cells but aggregated of nutrients. Second, most of elementary school teachers recognized that shapes of the cell in organisms were diverse, but some of them only could present several kinds of shape on cell. The 35% of teachers had misconception that shape of cell is all the same in a individual. It shows that this result is caused by lack of opportunity to observe the various kinds of cells. Third, most teachers understood tell can be seen only through a microscope. Yet in comparison with relative size, it was revealed that misconception of cell size was induced by the term of 'basic unit'. In addition, they thought that large organisms are built from large cells, and small organisms from small cells. Fourth, Elementary school teachers used to confuse the terms between chloroplast and chlorophyll, and believed that the genetic material was contained only in the reproductive cells and seeds. It was also revealed that they thought the nutrients such as starch and fat are located at intercellular space. Fifth, the 60% of teachers conceived correctly that growth of individual depends on mitosis and increase in cell number. The rest of them, however, misunderstood that it is due to the increase of tell volume.