• 한국연초학회지
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• 제13권2호
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• pp.52-58
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• 1991

Interspecific cross between Nicotiana trigonophylla and N. tabacum cv. BY4 is highly sterile because of abnormal ovule and embryo development. In vitro culture of excised N. trigonophylla ovules after polination by N. tabacum allows significant numbers of hybrid embryos to develop into mature plants. Total yield of seedlings and number of normal seedlings were produced following in vitro culture of individual fertilized ovules of N. trigonophylla X N. tabacum at four days post-pollination on B5 medium containing 6% sucrose. Hybrids were uniform in morphology and peroxidase isozyme composition and the majority were cytologically stable: flower characteristics were generally intermediate between those of the parents. All hybrids evaluated were self-sterile.

• Journal of the Korean Wood Science and Technology
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• 제21권1호
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• pp.7-14
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• 1993

To increase the production of mushrooms and the economic efficiency of mushroom cultivation, the pinchips(PC) and sawdusts(SD) of three Korean oak species were tested as cultivating media for Lentinus edodes with varing the composition of the media. The results are as follows. 1. Organic acids(tannic acid and citric acid), which were added in the PC medium to enrich the quality of mushrooms, did not increase the growths of the mycelia and the quality. 2. The mushrooms were able to be harvrested from six months after beginning the cultivation. No significant differences were found among the qualities of the mushrooms produced by various treatments. 3. The production rate of mushroom was relatively high with, 28.4~29.3% (700~730gr./2,500gr pack). The net profit estimated was about 1,450 won per pack.

• BMB Reports
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• 제28권3호
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• pp.261-264
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• 1995

The lipids of a Korean native blood-sucking leech (Hirudo nipponia) were isolated and analyzed. Cholesterol, fatty acids, triglycerides, glycerylether diester and cholesteryl esters were found from epidennal extracts. The major fatty acids in the leech skin were $C_{16:0}$, $C_{18:0}$, $C_{20:1}$. $C_{20:3}$ components. These components were derived from cholesteryl esters, glycerides, fatty acids and other polar lipids. After 60 days fasting, cholesterol, fatty acids and triglycerides in the skin were reduced in number and the total fatty acid composition was changed slightly. The data of total fatty acids in fasted and fed leech showed that medium-chain fatty acids were more affected than long-chain fatty acids. Other trace fatty acids appeared to be decreased by fasting.

• 한국식품영양학회지
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• 제11권4호
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• pp.388-393
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• 1998

This study was performed to investigate the influence of vadrious dietary fiber sources such as mugwort, apple, sea mustard, butterbur on the intestinal in aged rats. Nine groups of aged rats (12months after weanling) were fed each experimental diet containing 5% and 15% dietary fibers for 4 weeks. The contents in large intestine of aged rats used for the measurement of intestinal microflora. Total viable counts and the numbers of Bifidobacterium, Lactobacillus, Clostridium, E. coli and Staphylococcus were determined by nonselective medium and various selective media. The intake of dietary fiber sources employed did not show any differece in the number of total microorganisms, Lactobacillus and Bifidobacterium. It was remarkable that Clostridium perfringens appeared in the colon of aged rats. The prpulations of Peptococcus and Clostridium were significantly larger in the apple 5% group than in other dietary fiber groups while the number of Staphylococcus was significantly smaller in the dietary fiber groups than in cellulose group. And the Streptococcus populations decreased in the mugwort 15% group. Accordingly, the mugwort 15% group is effective in improving intestinal flora of aged rats.

• Journal of Microbiology and Biotechnology
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• 제1권1호
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• pp.6-11
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• 1991

This study deals with investigation of the ethanol tolerance of yeast strains with respect to fatty acid composition and intracelluar ethanol concentration during alcohol fermentation. The cell viabilities and fermentation abilities of Saccharomyces cerevisiae and Kluyveromyces fragilis were improved by aeration and addition of unsaturated fatty acids into growth medium. Aeration decreases the accumulation of ethanol, while increases unsaturated fatty acid contents inside yeast cells. Thus it was found that oxygen and unsaturated fatty acids play decisive roles in the increase of ethanol tolerance of yeasts.

• 한국수산과학회지
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• 제45권1호
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• pp.25-29
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• 2012

Marine actinomycetes isolated from seaweed were screened for growth activation effects on the biodiesel-producing microalgae Dunaliella salina. Of the 98 actinomycetes studied, strain 288-11 isolated from the rhizosphere of Undaria pinnatifida showed potent growth activation. The strain was identified as Streptomyces anulatus based on 16S rDNA sequence analysis. The cell density increased up to 2.1-fold with the addition of 1 mg/mL of extract to the medium. To understand the effect of adding S. anulatus extract, the gross biochemical composition and fatty acids of D. salina were determined.

• Journal of Nutrition and Health
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• 제27권10호
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• pp.988-995
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• 1994

This study was performed to investigate the influence of various dietary fiber sources(rice bran, Chinese cabbage, radish, apple, laver, sea mustard) on the intestinal microflora in rats. Eight groups of rats were fed each experimental diets containing 5% of total dietary fiber for 4 weeks. Total viable counts and the numbers of Bifidobacterium, Lactobacillus, Clostridium, E. coli and Staphylococcus were determined by nonselective medium and various selective media. The number of Bifidobacterium(p<0.01) was higher in the apple and sea mustard groups than those in the other groups and the number of Lactobacillus(p<0.01) was lower in the radish group. A decrease in the intestinal population of clostridium was shown in the sea mustard group. The E. coli(p<0.01) and Staphylococcus(p<0.01) populations decreased in the apple group compared with other groups. These findings suggest that the apple fiber and sea mustard fiber are effective in improving intestinal flora of rats.

• Asian-Australasian Journal of Animal Sciences
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• 제12권3호
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• pp.493-502
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• 1999

Majority of livestocks are kept in the tropics. Demand for animal products (meat and milk) is continuously increasing and is related to human population growth. Consequently, potential feeds should be continuously identified particularly on their nutritive values. Crop residues and agricultural by-products are the main feed sources for feeding livestock in the tropics. Their nutritive values ranging from low to medium quality level although Some agricultural by-products such as cotton seed meal and coconut meal are rich in nitrogaen contents. From literatures, nutritive values in these ingredients are mainly based on their chemical composition and to some extent based on limited number of in vivo studies. However, optimum of inclusion in the diet is suggested. Development of tree legumes should be thoroughly considered since they grow well in most tropical regions. In order to improve nutritive value of tropical feeds, biological treatments should be considered. Effect of secondary compounds decreasing efficiency of nutrient utilization in the rumen, to some extent could be reduced by introducing probiotics.

• 한국미생물·생명공학회지
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• 제23권2호
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• pp.220-228
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• 1995

For polyhydroxyalkanoic acid (PHA) production, several microorganisms were isolated from sewage sludge. One of them, GB-77 strain, was chosen from its PHB/HV copolymer production on only fructose without cosubstrate. The isolated strain GB-77 was identified as the genus Alcaligenes. Optimal temperature and pH for cell growth were 36C and 6.8. Optimal medium composition was 10 g/l of fructose and 5 g/l of polypeptone, 1 $\times$ 10$^{-2}$M Na$^{2}$HP0$^{4}$, 1.3 $\times$ 10$^{-2}$M KH$^{2}$PO$^{4}$. To investigate the optimal condition for polyhydroxyalkanoic acid production two-stage culture technique was used; first stage for cell growth and second stage for PHA production on unbalanced growth conditions. Optimal conditions for high PHA production were C/N ratio 50, temperature 36$\circ$C and pH 6.8. To overcome fructose inhibition on cell growth, intermittent feeding fed-batch culture technique was used. Total cell concentration was 17.4 g/l with 9.1 g/l of PHA. The purified PHA was identified PHB/HV copolymer by NMR analysis.

• 한국미생물·생명공학회지
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• 제15권5호
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• pp.328-333
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• 1987

고효율 에타놀 생성 균주인 Zymomonas mobilis의 plasmid vector가 숙주세포 내에서 안정하게 유지되는지의 여부를 회분 및 연속배양 방법을 통하여 조사하였다. Z. mobilis 숙주세포는 전이된 plasmid의 크기와 배지의 조성에 따라 증식속도에 영향을 받음을 알 수 있었고 작은 크기의 plasmid를 비 선택성 (non-selective) 배지에서 배양한 경우 더 빠른 성장을 보였다. 또한 사용한 4종류의 plasmid vector 모두 숙주세포 내에서 30세대 이상에 걸쳐 93% 이상의 높은 안정성을 나타내면서 독립적으로 증식함이 확인되었다.