• Journal of Life Science
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• v.16 no.3 s.76
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• pp.516-521
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• 2006

The possibility of usage as cosmetic resource of the mycelial culture broth of P. japonica in the mixture of cucumber and grape extracts was investigated. In the effect of collagen synthesis promotion in human fibroblast cells, the culture broth of P. japonica of 0.1, 0.5 and 1.0% concentration increased the amount of collagen synthesis than that of control cells. The culture broth increased the SOD activity in the concentration dependant manner of 0.01% to 1.0% in the antioxydation activity test. About 90% of superoxide radical was eliminated by 0.5% concentration of the culture supernatant in the antioxydation test. Anticoagulant quercetin in the course of mycelial growth in the mixture of cucumber and grape extract was accumulated to 15 folds than that of pre-culture. In the skin safety test of the culture broth, there is no any skin damage signal in the tested 30 people. Taken together, we concluded that the culture broth of P. japonica in the mixture of grape and cucumber extracts can be used as a cosmetic resource.

• KSBB Journal
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• v.22 no.1
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• pp.30-36
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• 2007

The water-soluble or ethanol-soluble materials extracted from fruit bodies and cultured products (mycelium and broth) of H. erinaceum were prepared, and their inhibitory effect on acetylcholinesterase (AChE) activity from Electrophorous electricus was investigated. Inhibition of 75-85% for AChE activity at concentration of 10 mg/ml was obtained and the mechanism was due to general non-competitive inhibition. Especially, the supernatant of culture broth by ethanol treatment, exhibited a strong inhibition activity of 94% at 10 mg/ml. The samples from fruit body, mycelium and broth (supernatant and precipitate by ethanol treatment) which were extracted from H. erinaceum, were very effective to inhibit the initial stage oxidation of a linoleic acid at concentration of 0.1 mg/ml. The antioxidative activity of these samples were superior than rutin, vitamin C and tocopherol as antioxidative standards by FTC (ferric thiocyanate) method, and also showed the very strong antioxidative activity of 95% without significant difference of the samples by TBA-RS (thiobarbituric acid-reactive substance) method.

• Parasites, Hosts and Diseases
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• v.28 no.4
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• pp.197-206
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• 1990

Various conditions of cultures were performed to investigate the role of tight junctions formed between adjacent MDCK cells on the entry of Toxoplasma. When MDCK cells were cocultured with excess number of Toxoplasma at the seeding density of 1×105, 3×105, and 5×105 cells/ml for 4 days, the number of intracellular parasites decreased rapidly as the host cells reached saturation density, i.e., the formation of tight junctions. When the concentration of calcium in the media (1.8 mM in general) was shifted to $5{\mu}M$ that resulted in the elimination of tight junction, the penetration of Toxoplasma increased about 2-fold(p<0.05) in the saturated culture, while that of non-saturated culture decreased by half. Trypsin-EDTA which was treated to conquer the tight junctions of saturated culture favored the entry of Toxoplasma about 2.5-fold(P<0.05) compared to the non-treated, while that of non- saturated culture decreased to about one fifth. It was suggested that the tight junctions of epithelial cells play a role as a barrier for the entry of Toxoplasma and Toxoplasma penetrate into hoot cells through membrane structure-specific, i.e., certain kind of receptors present on the basolateral rather than apical surface of MDCK cells.

• Research in Plant Disease
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• v.17 no.2
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• pp.121-128
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• 2011

Bacteriolytic myxobacteria have been known to secrete various antifungal metabolites against several soilborne phytopathogens including Phytophthora. Among the three isolates of Myxococcus spp., KYC 1126 and KYC 1136 perfectly inhibited the mycelial growth of Phytophtora capsici in vitro. In order to show the biocontrol activity on Phytophthora blight of hot pepper, we tried to find the best way of application of a myxobacterial isolate. Although KYC 1126 fruiting body was easily grown on the colony of Escherichia coli as a nutrient source, it did not control the disease when it was pre-applied in soil. Before the bioassay of a liquid culture filtrate of KYC 1126 was conducted, its antifungal activity was confirmed on the seedlings applying with the mixture of the pathogen's zoospore suspension and KYC 1126 filtrate. On greenhouse experiments with five and four replications, the control value of KYC 1126 on phyllosphere and rhizosphere was 88% and 36%, respectively. Whereas, the control value of dimetnomorph+propineb on phyllosphere was 100% and that of propamorcarb on rhizosphere was 44%. There was a phytotoxicity of the myxobacterial filtrate when seedlings were washed and soaked for 24 hours. Gummy materials were covered with roots. And stem and petiole were constricted, then a whole seedling was eventually blighted.

• KSBB Journal
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• v.14 no.3
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• pp.303-308
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• 1999

An in vitro culture method for entomopathogenic nematode Steinernema glaseri was developed. A symbiotic bacterium was isolated from Steinernema glaseri and identified as Xenorhabdus nematophilus. Phase variation that differed in some biochemical characteristics of symbiotic bacterium was observed. Entomopathogenic nematodes carried only phase I bacterium in their guts. Phase I bacterium could be converted into phase II form in in vitro culture medium consisting of 5% yeast extract, 0.5% NaCl, 0.05% $K_2HPO_4$, $0.02% MgSO_4$.$7H_2O$. The optimum temperature for bacterial growth was $28^{\circ}C$. The pH of the culture medium increased up to 9.0-9.5 during the exponential growth period of the culture, regardless of initial pH 6-7. Various culture media such as chicken offal, dog food, bovine liver, peanut, and so on were tested for in vitro culture of the nematodes. The best medium for Steinernema glaseri production was obtained from concentrated homogenate of bovine liver and the nematode growth was highest at 80% bovine liver. In the co-culture of entomopathogenic nematode with its symbiont, the growth rate of nematodes was 2 times faster than that without its symbiont and the nematode concentration reached about $5.5\times10^4$/mL within 15 days.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.262-266
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• 2016

Marine copepods are ideal live prey for fish larvae, and many studies on the mass culture of the organism have been reported. This study performed a mass culture of the brackish copepod Paracyclopina nana containing nauplius and C4-adult production methods. In nauplius production, the harvested nauplii over 95% were comprised of N1 and N2. Daily mean nauplius production of two trials for 15 days were $6.9{\times}10^6$ and $7.2{\times}10^6$ individuals, respectively. The densities of the adult females were maintained at a similar level of the initiation during production. In C4-adult production, the proportion of harvested copepods containing C4-adult males, females and ovigerus females were 49%, 28%, and 18%, respectively. The daily mean nauplius production of the two trials for 16 days were $8.2{\times}10^5$ and $9.0{\times}10^5$ individuals, respectively. As a result, the continuous production of P. nana using the mass production system was successful. Therefore, the continuous and stable feeding for fish larvae in aquaculture would be possible by the selection of the copepod culture method depending on the mouth size of the fish.

• Korean Journal of Food Science and Technology
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• v.4 no.3
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• pp.200-205
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• 1972

Effects of several different petroleum fractions (LGO, HGO, VGO, Diesel oil, SP(E), HGO-wax, L/M-wax), stepwise addition of calculated amounts of HGO at defined intervals, recycling of spent media on cell growth of Candida tropicalis KIST 351 were studied using $2.5{\ell}$ fermenter by batch process. In addition, continuous cultivation of the yeast was also performed in the light of biomass production using $28{\ell}$ fermenter with LGO. 1) Cell concentration, yield on the basis of gas oil and n-paraffin with the petroleum fractions were in the range of $11{\sim}15g/{\ell}$, $10{\sim}12%$ and $77{\sim}82%$, respectively. 2) By stepwise addition of the gas oil, cell concentration and yield on the oil were increased up to 18.9 g/land 13%, respectively. 3) Spent medium slowed emulsifying ability of hydrocarbon and stimulating effect on the cell growth. Without additional supplementation of $Mg^{++}$ up to 20% of spent medium could be reused, while by adding of the $Mg^{++}$, 50% of medium could be recycled. 4) Optimum condition of continuous cultivation for biomass production was attained at the dilution rate of $D=0.1{\sim}0.125\;hr^{-1}$. Maximum yield coefficient on consumed n-paraffin was 0.94 at $D=0.1\;hr^{-1}$, however, 24% of supplied n-paraffin in the media was not utilized at this dilution rate.

• The Korean Journal of Mycology
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• v.22 no.3
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• pp.266-275
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• 1994

Brewer's yeast extract can be used as a good substrate for the culture of Lentinula edodes Mycelia(LEM). We found that it was better to filter the extract through three kinds of sieves and then to heat for hydrolysis and concentration at $90^{\circ}C$ prior to use. Also the maximum condition for the growth of LEM was investigated. We found that addition of inorganic salts such as calcium enhanced the growth of LEM. On the other hand, addition of carbon and nitrogen sources to the medium did not affect, and even inhibited under certain conditions, the growth of LEM. The maximum temperature for the growth of LEM was around $25^{\circ}C$. Also, it grows better when agitated by shaking at 100 rpm for airration. The appropriate concentration of the extract to use was 10%. Under these conditions, LEM could reach to the confluency after cultivation of 12 days. Our extract formula seems better than other available media for LEM growth, producing higher crude protein content and better taste.

• The Korean Journal of Zoology
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• v.37 no.1
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• pp.58-65
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• 1994

Phosphatase의 저해제로 알려진 okadaic acid(OA)가 한국산 개구리(북방산개구리 참개구리) 난자의 성숙에 미치는 효과를 조사하였다. 북방산개구리 난자에 약 50 nl의 okadaic acid(0 5-500 mM)를 미세주입한 후 18시간 배양한 결과 0.5 mM의 농도에서 부터 난자의 핵붕괴를 일으키기 시작하였다 동면초기에 처리한 progesterone에 반응하지 않는 난자들도 OA에 의하여 성숙을 일으켰으며. 이 성숙은 배양액에 첨가한 cycloheximide(10 mg/ml)에 영향을 받지 않았다 또한 OA의 처리를 받고 일정시간 배양한 난자의 세포질에는 미성숙 난자의 성숙을 유도하는 maturation promoting factor (MPF)의 활성이 생기었다 참개구리의 난자도 역시 OA에 의해 성숙이 유도되었으며, 주입 후 6시간에서부터 핵붕괴가 일어나기 시작하였다 참개구리에서도 OA의 처리가 MPF의 활성을 촉진하는 것을 세포질내에 Hl histone kinase의 활성도가 증가하는 것으로 확인할 수 있었다 참개구리에서도 OA에 의한 성숙은 cycloheximide나 CAMP에 의해 영향을 받지 않았다 이러한 결과들은 개구리 난자의 MPF 활성화와 성숙과정에 phosphatase가 관여함을 보여주는 것이다.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.186-191
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• 2002

실시간 온라인 계측에 의한 순환식 양액조제 알고리즘을 위해서 이온센서를 사용하였다. 이온센서의 내구성이 약하고 배양액 내에는 이온센서의 정확한 계측의 방해요인인 이온성분들이 포함되어 있기 때문에 매번 정확한 측도 설정을 수행 해줌으로써 계측값의 신뢰도를 높일 수 있었고 이온센서를 이용한 온라인계측의 가능성을 확인할 수 있었다. 그러나 배양액 속에 장시간 넣어둔 상태로 사용하였을 경우 4시간 이상 경과하면 센서에서 나오는 신호가 지속적으로 상승하는 경향을 보였다. 장시간 동안 배양액에 노출되었던 센서는 측도설정이 불가능한 수준으로 일정농도의 용액 내에서 일정한 값을 나타내지 못하고 계측값이 지속적으로 상승하던가 하강하여 한계값 까지 이르렀다. 이러한 이유로 연구용이 아닌 실제 장치에 적용하여 실용화하기 위해서는 내구성이 강하고 계측하고자 하는 이온에 대해 영향을 주는 방해이온 속에서도 정확도를 유지 할 수 있는 센서의 개발이 선행되어야 한다. 또한 정확한 퇴액 성분의 측정을 위해서는 측도 설정이 선행되어야 하는데 계측이 필요할 때마다 측도 설정을 자동으로 해줄 수 있는 자동 측도 설정 모듈의 개발도 수행되어야 할 것으로 사료된다.