• Journal of Plant Biology
• /
• v.14 no.1
• /
• pp.33-35
• /
• 1971

After topping, axillary buds of haploid plants derived from cultured anthers were treated with 0.4% aqueous solution of colchicine. Due to the high temperature and dry air at the time of treatment, most of the buds perished. A few months after the colchicine application, however, several shoots arose from the places where the dead buds were originally located. These shoots were mostly diploid. Induction of adventive shoots from the colchicine-treatedaxils was supposed to be rather effective method of obtaining diploid shoots from haploid plants. The diploid plants had larger floral organs than the haploid plants, and had good pollen fertility and seed setting. 24 bivalent chromosomes were observed at MI of the PMC's.

• Journal of Plant Biology
• /
• v.19 no.2
• /
• pp.45-48
• /
• 1976

Anthers of cultivated Paeonia albiflora were cultured on media supplemented with various combinations of growth regulators. Although the number of anthers with emerged calluses were very few, in the sectioned anthers were found many multinucleate, 2-celled, or multicellular microspores, the one-celled multinucleate microspores being most abundant in number, and the multicellular ones the least. In 2-celled or 3-celled microspores two kinds were observed: one is ordinary one with single nucleus in each cell, and the other is multinucleate one. Majority of the 2-celled microspores was found to be of equational-division irrespective of whether they were multinucleate micropores or ordinary nonmultinucleate ones.

• Animal Systematics, Evolution and Diversity
• /
• v.10 no.2
• /
• pp.199-205
• /
• 1994

In the life cycle of Coryne pusilla Gaertner, a medusa is lacking and the planula larvae represent the only known dispersive stage. The planula larvae crawled on the surface of culture vessel for about 21 hours after release, and settle down and start metamprohosis.

• Proceedings of the Korean Society for Applied Microbiology Conference
• /
• 1976.04a
• /
• pp.184.4-184
• /
• 1976

Cheese제조에 이용할 수 있는 우유응고효소를 미생물 발효로써 생산할 목적으로 먼저 자연계에서 균주를 분리 선정하였다. 토양 및 메주로부터 분리한 200주의 미생물 가운데 약 50주가 2시간 이내에 curd를 형성하였으나 대부분이 proteolytic activity가 너무 커서 그대로는 이용할 수가 없음을 알았다. 그중에 유망한 균주 하나를 pH를 달리하여 배양해 보았더니 acid쪽에서 neutral보다 clotting/proteolytic ratio가 1.7배나 증가함을 확인하였다.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 1988.02a
• /
• pp.94-95
• /
• 1988

• 한국생물공학회:학술대회논문집
• /
• 2000.04a
• /
• pp.243-246
• /
• 2000

Clostridium acetobutylicum Bl8 can produce a large amount of butanol by control characteristics such as glucose concentration, pH and extra nutrient. It is known that this stain is potentially useful in simultaneous ABE fermentation-seperation system because of its low acid $production^{1).}$ The purpose of this study is to determine optimal condition of fermentation to produce maximum butanol in batch and fed-batch by strain Bl8.

• Korean Journal of Food Science and Technology
• /
• v.21 no.6
• /
• pp.832-837
• /
• 1989

It has been suggested that medium chain fatty acid(MCFA) may be toxic to yeast and bacteria and thus play a role in the inhibition of alcoholic and malolactic fermentations and also important contributors to wine flavour We measured, by the use of GLC, the concentrations of octanoic, decanoic and dodecanoic acids produced by 12 wine yeast strains during the alcoholic fermentation of a grape juice-like medium. In general, there was a high production of MCFA at first, dropping dramatically later. The formation of MCFA is largely dependent on yeast strain but it also depends upon temperature, sugar concentration, stirring and carbon dioxide sparging.

• The Korean Journal of Zoology
• /
• v.35 no.1
• /
• pp.37-44
• /
• 1992

북방산개구리, 참개구리 및 옴개구리를 사용하여 성숙된 난자의 세포질에서 활성을 띠는 성숙촉진요인( maturation promoting factor, MPF)을 미세주입 법으로 확인하고 이들의 성질을 조사하였다. 핵붕괴(germinal vesicle breakdown, GVBD)된 난자의 세포질을 미성숙 난자(GV난자)에 주입하고(75-100 nl) 이들을 15-24시간 배양했을 때 대부분의 GV 난자들이 핵붕괴를 일으켰으나(약 80%) 미성숙 난자(GV 난자)의 세포질을 주입했을 때에는 약 200nl의 난자들만이 핵붕괴를 일으켰다. 핵붕괴된 난자들의 crude extract를 주입했을 때에도 역시 성숙유도 효과가 있었으며 이종간에도 효과가 있었다. 난자의 성숙을 잘 일으키지 않는 옴개구리의 난자를 사용하여 MPF를 가진 세포질을 계대주입(serial transfer)하였을 때에도 MPF가 계속 활성을 띠는 것을 확인할 수 있었다. 아울러 개구리 난자의 MPF생성과 증폭과정에 CAMP의 증가나 단백질 합성의 저해가 미치는 영향을 조사한 결과. MPF의 작용이 유의하게 이들에 의해 억제되는 것을 알 수 있었다.

• Journal of the Korean Society of Tobacco Science
• /
• v.16 no.1
• /
• pp.64-68
• /
• 1994

The present experiments were conducted to investigate some of the factors affecting the number of haploids derived from anther culture of Nicotiana tabacum. Anther - donor plants grown under controlled environment room at 3$0^{\circ}C$ yielded more haploid than room at 18, 25 and 26-22-18$^{\circ}C$ in anther culture. Donor plants starved of fertilizer yielded more haploids as compared to those of the well fed with fertilizer in anther culture. Pretreatment of exercised flower bud at 5$^{\circ}C$ was shown to be more effective in anther culture than pretreatment at 7 and 1$0^{\circ}C$, and the optimum temperature and period of pretreatment were 4 or 6 days at 5$^{\circ}C$.

• Korean Journal of Food Science and Technology
• /
• v.34 no.2
• /
• pp.249-254
• /
• 2002

To determine the abilities as both lactic starter and probiotics for fermented foods, we investigated the potency of acid production, proteolytic activity and lactose metabolism of Lactobacillus amylovorus IMC-1. And the strain was cultured with lactococci in 10% skim milk medium. It was also examined the bactericidal action of antibacterial substance, produced by the strain IMC-1, against pathogenic bacteria. L. amylovorus IMC-1 showed excellent production of acid in 10% skim milk supplemented with yeast extract, and produced 0.8 and 2.7% of acid at 12 and 72 h incubation, respectively. It was found that the activity of ${\beta}-galactosidase$, about $39\;{\mu}M/minute/dry$ cell weight (mg), was stronger than that of $phospho-{\beta}-galactosidase$ in the strain IMC-1. The strain showed weak proteolytic activity in 10% skim milk, thus it produced 6 and $69\;{\mu}g/mL$ of free tyrosine at 12 and 72 h cultivation, respectively. It was known that the strain utilized mainly ${\alpha}-casein$ than ${\beta}-casein$ from patterns of SDS-PAGE. Mixed culture produced more acid than single cultures of L. amylovorus IMC-1 and Streptococcus thermophilus NIAI 510. Single culture of Str. thermophilus and mixed culture showed increasing cheese flavor with incubation times. Optimal fermentation time of mixed culture for the acid production and flora of lactic starter was 16 and 12 h by adding 0.1 and 0.5% of yeast extract to 10% skim milk, respectively. Antibacterial substance produced by the strain IMC-1 reduced about 2 log of the viable cell counts of both Escherichia coli O157 and Shigella flexneri after 24 and 4 h incubation, and they were not detected after 48 and 6 h incubation, respectively.