• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.395-399
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• 2003

Nebramycin is a complex of aminocyclitol compounds that is produced by aerobic culture in fermentation process. The major antibiotic factors produced by Streptoalloteichus hindustanus are nebramycin factor 2, 4, 5'and kanamycin A. A mutant was selected, producing nebramycin factor 5' activity 16.4 times higher than parent strain by microbiological assay using Pseudomonas aeruginosa CH-U34AF. The component ratio of nebramycin factor 5' was dramatically increased from 34% to 70% by the optimization of fermentation condition. It was found that the component ratio of nebramycin factor 5' in fermentation was especially affected by the oxygen transfer rate. Optimum oxygen transfer rate for maximal nebramycin factor 5' productivity and ratio during S. hindustanus fermentation was elucidated to $0.50 mMO_2$/min.

• Korean Journal of Plant Tissue Culture
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• v.27 no.3
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• pp.163-167
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• 2000

This study was carried out to identify varietal difference and the inheritance of the ability of plant regeneration in anther culture of rice. The anthers of 33 Japonica, 11 Indica/Japonica, and 3 Indica rice cultivars were culture on $N_6-Y$_1$$ medium with 1 mg/L NAA and 2 mg/L kinetin. The remarkable variability in plant regeneration were observed among the genotypes, ranging from 0.0% to 19.4% Most of Japonica rices were resulted to have better culturability than that of Indica/Japonica and Indica type cultivars. Newly developed Japonica rices, 'Ilmibyeo' and 'Hangnambyeo' showed to have regenerability with the frequency of 19.4% and 18.1% respectively. The segregation mode for callus formation and plant regenerationin anther culture of F$_2$ population of 'Milyang 23/Chucheongbyeo' showed a continuous variation. The variation of plant regeneration frequency in anther culture of F$_2$ plants ranged from 0% to 33.3% with a mean of 6.3% The broad-sense heritability estimated from the ability of plant regeneration was considerably high (82.7%).

• Applied Chemistry for Engineering
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• v.25 no.3
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• pp.324-329
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• 2014

Microalgae Nannochloropsis oculata (N. oculta) and Chlorella vulgaris (C. vulgaris) are important sources for biodisel because of the high content of neutral lipids. Stable nano bubble is maintained for a long time and therefore it is possible for use in biotechnology. In this study, effects of nano bubble oxygen or hydrogen water on the microalgae growth were characterized. The cell growth in nano bubble water was similar to that of control, and the total lipid content was rather low. But, chlorophyll content of N. oculata grown in nanno bubble oxygen and hydrogen water increased 54% and 30%, and increased 59%, 39% in C. vulgaris. Carotenoid content also increased 21%, 25% in N. oculata and 49%, 29% in C. vulgaris grown in nano bubble oxygen and hydrogen water. From these results, nano bubble water seems to enhance the photosynthetic capacity of microalgae.

• Journal of Mushroom
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• v.17 no.3
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• pp.126-131
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• 2019

This study sought to identify the optimum substrate composition for the stable bottle cultivation of Sparassis latifolia. The main substrate was fermented larch sawdust. Six nutrient sources were mixed at a maximum volume ratio of 20%. The fresh weight of fruit body was the highest at 128.5 g for GMSL69033 and 126.6 g for 'Neoul' in the treatments of beet pulp and corn flour in a volume ratio of 15:5. In addition, the total cultivation period was 94 days, which was shorter than that required for other treatments. The selected substrate characteristics were pH 4.7, C:N (carbon to nitrogen) ratio of 106:4, moisture content of 70%, and air filling porosity of 38%. We plan to develop new income items through research on mycelial incubation and fruit body growth conditions.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.23-23
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• 2003

김 붉은갯병은 김 엽체에 난균류 Pythium속의 Pythium porphyrae의 기생에 의해 발생되어 매년 김 양식에 큰 피해를 주는 매우 심각한 김 갯병중의 하나이다. 최근에는 이들 병해의 발생 및 억제를 위한 김 산처리제 (활성처리제) 남용에 따른 연안 양식어장의 생태계 파괴 및 김의 자연식품에 대한 이미지 훼손 등의 문제점이 대두되고 있다. 따라서 본 연구에서는 김 양식시 발생되는 붉은갯병의 병해를 억제하고자 활성처리제 처리시 고염분해수 처리를 병용함으로써 활성처리제의 사용을 최소화하면서 처리효과를 배가시키고자 하였다. 시험에 사용한 김 엽체는 2002년 10월에 전라남도 해남군 황산면 지선에서 채묘한 방사무늬김 (Porphyra yezoensis)을 육묘해 엽장 1cm 내외에서 냉동망을 제작하여 -2$0^{\circ}C$에 저장한 엽체를 자연해수 (약 27$\textperthousand$), 15$^{\circ}C$, 100$\mu$mol photon m$^{-2}$ s$^{-1}$, 광주기 9L : 15D의 배양조건하에서 15일간 배양한 엽장 3-4cm 정도의 것이었다. 활성처리제와 고염분해수처리제의 병용에 의한 붉은 갯병 억제효과는 붉은갯병 병원균의 유주자를 김 엽체에 감염시킨 후 27$\textperthousand$의 자연해수에 12일간 배양하면서 염분농도를 3-25%, 처리주기를 1-2회로 하여 각 시험구별 병해정도로 평가하였다. 고염분해수 처리에 의한 붉은갯병균 균사의 생장억제 효과는 김 엽체를 붉은갯병 병원균의 유주자로 감염시킨 다음 감염 12시간 후 염분농도를 3-25%로 처리한 후 27$\textperthousand$의 자연해수에 4일간 배양하면서 각 시험구별 배양시간에 따른 병원균 균사에 의한 김 엽체의 감염세포수로 평가하였다. 활성처리제와 고염분해수처리제의 병용이 김 엽체 생장에 미치는 영향은 건전한 김 엽체의 절편을 27$\textperthousand$의 자연해수에 배양하면서 시험구별로 활성처리와 고염분해수 (5, 10, 15, 20, 25%) 처리를 3일 간격으로 하면서 12일간 배양한 후 엽체의 엽면적 증가율로 평가하였다. 활성처리제와 고염분해수처리제의 병용에 의한 붉은갯병의 억제효과는 대조구 (활성처리 1회)와 비교해 주 2회의 활성처리구와 염분농도 20, 25% 처리구에서 병해 억제효과가 월등히 높았다. 고염분해수 처리에 의한 붉은갯병균 균사의 생장억제 효과는 염분농도 5, 10% 처리구의 경우 무처리구에 가까운 감염세포수를 보였으나, 염분농도 20, 25% 처리구의 경우 활성처리제 처리와 비슷한 감염세포수를 보여 뚜렷한 생장 억제효과를 나타냈다. 활성처리와 고염분해수 처리의 병용이 김 엽체 생장에 미치는 영향은 대조구 (활성처리 1회)의 3.4배 생장율과 활성처리와 염분농도 5-20%의 고염분해수 병용 처리구의 3.1-3.6배 생장율은 유의한 생장차이를 보이지 않았다 (P<0.05).

• Korean journal of applied entomology
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• v.1
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• pp.42-46
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• 1962

1) The purpcse of the present study is to investigate the effects of culture filtrates of Fuarsium oxysporum f. vasinfectum which is known to produce wilt toxin (fusaric acid) on the germination of host plants (sesame, cotton) and non-host plants (wheat, rice). 2) The experiment on the germination of sesame, cotton, wheat and rice seeds in the seed beds separately added with culture filtr ates of 10 differential strains of Fusarium oxysporom f. vasinfectum demonstrated that culture filtrates of most strains of the fungus inhibit or retard the germination of seeds of 4 plants used in this study while those of a few strains do not give notable influence on the germination of seeds of those plants. a) Culture filtrates of strain 201 of the fungus strongly inhibited the germination of seeds of those plants in nearly same degree, but culture filtrates of the other strains, 281, 321, etc., showed remarkable differences in the toxicity inhibiting or retarding the germination of the seeds of those plants. b) In general, sesame seeds are greatly susceptible, wheat and cotton seeds are moderately susceptible and rice seeds are resistant to the toxicity of culture filtrates of the fungus. 3) In the soil containing a number of differential strains of Fusarium oxysporum f. vasinfectum, the germination of seeds and also the growth of seedlings of non-host plants are possibly checked by the toxic substance, fusaric acid produced by the fungus.

• KSBB Journal
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• v.10 no.1
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• pp.78-88
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• 1995

The encapsulatpd A. niger grew up inside the capsule and mycelia penetrated through the pore of the capsule membrane. The mycelia on the capsule wall became loose when the carbon source and oxygen were deficient in the medium. On the contrary, the production rate increased and mycelia made a lump tightly when the carbon source and oxygen were sufficient. Namely, number of proper capsule of unit volume in the medium was existed. The phenomenon which was swelled of capsule membrane in cultivation could prevented by adding CaCl2 into the medium. According to the time adding CaCl2 into the medium, the production rate of citric acid was influenced. In case of adding CaCl2 into the medium at 7th day cultivation, the production yield of citric acid was increased about 40 percent higher than that of adding CaCl2 initially. The production yield of citric acid using encapsulated A. niger of flask culture was influenced with oxygen supply. The production yield of citric acid ($\Delta$p/$\Delta$s) of the flask culture was increased 3.88 time by using T-flask instead of parafilm sealed flask. Therefore, the productivity and consumption rate concerning production which was taken carbon source were increased when oxygen supply was sufficient. The production of citric acid using encapsulated A. niger was increased average 30 percent higher than that of bead in between 6th and 13th day cultivation.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.250-256
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• 2003

Lactic acid bacteria with amylolytic and acid producing activities can ferment starch directly to lactic acid thereby producing a monomer for the production of biodegradable poly lactic acid (PLA). In this study, the strain producing L-lactic acid from soluble starch was isolated from Nuruk. The isolated strain was identified as Enterococcus sp. through its morphological, cultural, biochemical characteristics as well as the 16S rDNA sequence analysis, and named Enterococcus sp. JA-27. Enterococcus sp. JA-27 produced exclusively L-lactic acid from soluble starch as a carbon source. The optimal conditions for the maximum production of L-lactic acid from Enterococcus sp. JA-27 were 30 C, pH 8, 1.5 % soluble starch as a substrate and 3.5 % tryptone as a nitrogen source, 0.1 % $K_2$$HPO_4$, 0.04 % $MgSO_4$. $7H_2$O, 0.014 % $MnSO_4$$.$4$H_2O$, 0.004% $FeSO_4$$.$$7H_2$O. Batch and fed batch culture were carried out and the former was more effective. L-Lactic acid production in the optimum medium was significantly increased in a 7 L jar fermenter, where the maximum L-lactic acid concentration was 3 g/L. For the purification of lactic acid in fermented broth, two stage ionexchange column chromatographies were employed and finally identified by HPLC.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.33-33
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• 2001

본 연구는 한우 난포발달에 있어서 난포액 및 inhibin의 생리적 역할을 검토하기 위해 수행하였다. Anti-inhibin serum(AIS) 생산을 위해 사용된 항원은 porcine inhibin-$\alpha$-subunit 19~32의 peptide를 사용하여 adjuvant 용액을 1:3의 비율로 혼합하여 앙고라종 토끼 5두(체중 2.5kg)에게 주 2회 간격으로 8회 실시후 ELISA Leader로 항혈청의 역가를 확인하였다. 난포액(bFF; bovine follicular fluid)은 도축장에서 도축되는 한우 난소로부터 직경 1.0cm 이하의 난포로부터 회수하여 스테로이드를 제거하기 위해 10% chacoal solution(50 mg/$m\ell$, Norrit-A, Fisher Sci., USA)을 처리하여 45분간 배양후 원심분리후 상층액을 회수하여 실험에 공시하였다. 과립막세포의 체외배양을 위해 D-MEM용액(10% FCS와 antibiotics를 첨가)을 배양액으로 하여 1 $\times$ $10^{6}$ cells/$m\ell$로 조절하였다. 호르몬은 RIA 및 ELISA법으로 분석하였다. 그 결과 항원-항체반응은 항원처리후 24일째부터 항체가를 확인할 수 있었으며 52일째에서 높은 항원-항체반응을 보였다. 한편, 난포크기별 난포액의 progesterone 및 Estradiol-l7$\beta$을 농도를 분석한 결과, Progesterone 난포크기가 직경 1.0 cm부터 유의적으로 증가하기 시작하여 직경 2.0cm의 난포액에서는 높은 progesterone이 존재하고 있는 것으로 나타났다. 이에 반해, 난포크기별 난포액중 estradiol 17$\beta$농도는 직경 1.0cm구에서 가장 높게 나타났다. 난포직경이 1cm일 경우에 난포액내 etradiol-17$\beta$가 가장 많이 존재하고 있음이 나타났다. 과립막세포의 체외배양에서 배양 24시간에서는 과립막세포의 progesterone분비는 약 40ng/1$\times$$10^{6}$ cell/well/$m\ell$ 전후로 나타났으며 bFF 5%, AI 5% 및 bFF＋AI 첨가구에 따라 유의적인 차이는 없었다 반면에 48시간배양구에서는 24시간에 비해 유의적으로 높게 분비되었으며, bFF 5%처리구와 bFF5%＋AI5%처리구에서는 progesterone을 대조구보다 유의적으로 억제되었으나 AI 5%단독처리구에서는 대조구와 큰 차이가 없었다. 한편, 각 세포질을 SDS-PAGE로 분리하여 nitro cellulose membrane에 transfer하여 Western blotting법에 의해 검토한 결과, 직경 1.0 cm의 성숙난포의 granulosa cell에 특이하게 Inhibin이 존재하고 있음이 확인되었다. 이상의 결과로, 한우에 있어서 성숙난포에 존재하는 Inhibin은 난포발달 및 난포세포의 스테로이드호르몬합성에 중요하게 관여하고 있는 것으로 사료된다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.23 no.3
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• pp.109-124
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• 2018

In order to find the optimum culture condition for marine free-living nematoda in the laboratory, various agar media were developed and experiments were carried on nematodes. Nematodes have collected from the bottom of the sandy sediments' surface layer (about 5cm sediment) of Taean Mallipo beach's intertidal zone. Especially, with regard to agar medium, Killian medium was transformed slightly, density of agar had made a difference and this agar medium(height 2.0 mm on diameter 60 mm Petri dish) was divided. It was mixed with 5 different species of microorganism as nematodes' live food and added each culture medium. Five individuals of Enoplolaimus sp. on each culture medium were grown in a culture medium which was set on $20^{\circ}C$ and light blocked. Moreover, as a result of the optimum culture condition, 1.0% density of agar showed the highest survival rates (the average time of survival is 246.8 hours). On the other hand, the 0.4% density of agar adding Killian medium, bacto peptone and beef extract showed the lowest survival rates, which indicates the average time of survival is 27.6 hours. About Bathylaimus sp., on Killian medium's 1.0% density of agar(no feeding amount) showed the highest survival rates, which connects that the hatching rate 94.7% after 99.5 hours and it laid 7 eggs averagely on the spawning amount and the hatching rate experiment.