• Microbiology and Biotechnology Letters
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• v.43 no.2
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• pp.134-141
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• 2015

An agarolytic marine bacterium (H9) was isolated from the coastal seawater of the West Sea, South Korea. The isolate, H9, was gram-negative and rod-shaped with a smooth surface and polar flagellum. Cells grew at 20-30℃, between pH 5.0 and 9.0, and in ASW-YP (Artificial Sea Water-Yeast extract, Peptone) media containing 1-5% (w/v) NaCl. The G+C content was 41.56 mol%. The predominant isoprenoid quinone in strain H9 was ubiquinone-8. The major fatty acids (>10%) were C_16:1ω7c (34.3%), C_16:0 (23.72%), and C_18:1ω7c (13.64%). Based on 16S rRNA gene sequencing, and biochemical and chemotaxonomic characterization, the strain was designated as Pseudoalteromonas sp. H9 (=KCTC23887). In liquid culture supplemented with 0.2% agar, the cell density and agarase activity reached a maximum level of OD = 4.32 (48 h) and OD = 3.87 (24 h), respectively. The optimum pH and temperature for the extracellular crude agarases of H9 were 7.0 and 40℃, respectively. Thin-layer chromatography analysis of the agarase hydrolysis products revealed that the crude agarases hydrolyze agarose into neoagarotetraose and neoagarohexaose. Therefore, the new agar-degrading strain, H9, can be applicable for the production of valuable neoagarooligosaccharides and for the complete degradation of agar in bio-industries.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.880-884
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• 2001

Rumen microbiology research has undergone several evolutionary steps: the isolation and nutritional characterization of readily cultivated microbes; followed by the cloning and sequence analysis of individual genes relevant to key digestive processes; through to the use of small subunit ribosomal RNA (SSU rRNA) sequences for a cultivation-independent examination of microbial diversity. Our knowledge of rumen microbiology has expanded as a result, but the translation of this information into productive alterations of ruminal function has been rather limited. For instance, the cloning and characterization of cellulase genes in Escherichia coli has yielded some valuable information about this complex enzyme system in ruminal bacteria. SSU rRNA analyses have also confirmed that a considerable amount of the microbial diversity in the rumen is not represented in existing culture collections. However, we still have little idea of whether the key, and potentially rate-limiting, gene products and (or) microbial interactions have been identified. Technologies allowing high throughput nucleotide and protein sequence analysis have led to the emergence of two new fields of investigation, genomics and proteomics. Both disciplines can be further subdivided into functional and comparative lines of investigation. The massive accumulation of microbial DNA and protein sequence data, including complete genome sequences, is revolutionizing the way we examine microbial physiology and diversity. We describe here some examples of our use of genomics- and proteomics-based methods, to analyze the cellulase system of Ruminococcus flavefaciens FD-1 and explore the genome of Ruminococcus albus 8. At Illinois, we are using bacterial artificial chromosome (BAC) vectors to create libraries containing large (>75 kbases), contiguous segments of DNA from R. flavefaciens FD-1. Considering that every bacterium is not a candidate for whole genome sequencing, BAC libraries offer an attractive, alternative method to perform physical and functional analyses of a bacterium's genome. Our first plan is to use these BAC clones to determine whether or not cellulases and accessory genes in R. flavefaciens exist in clusters of orthologous genes (COGs). Proteomics is also being used to complement the BAC library/DNA sequencing approach. Proteins differentially expressed in response to carbon source are being identified by 2-D SDS-PAGE, followed by in-gel-digests and peptide mass mapping by MALDI-TOF Mass Spectrometry, as well as peptide sequencing by Edman degradation. At Ohio State, we have used a combination of functional proteomics, mutational analysis and differential display RT-PCR to obtain evidence suggesting that in addition to a cellulosome-like mechanism, R. albus 8 possesses other mechanisms for adhesion to plant surfaces. Genome walking on either side of these differentially expressed transcripts has also resulted in two interesting observations: i) a relatively large number of genes with no matches in the current databases and; ii) the identification of genes with a high level of sequence identity to those identified, until now, in the archaebacteria. Genomics and proteomics will also accelerate our understanding of microbial interactions, and allow a greater degree of in situ analyses in the future. The challenge is to utilize genomics and proteomics to improve our fundamental understanding of microbial physiology, diversity and ecology, and overcome constraints to ruminal function.

• Microbiology and Biotechnology Letters
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• v.36 no.2
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• pp.106-114
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• 2008

One bacterium, which showed strong antagonistic activity against H. pylori KCCM 41756, was isolated from kimchi. The strain NO1 was designated as Lactobacillus plantarum NO1 based on Gram staining, biochemical properties, and 16S rRNA gene sequencing. The culture medium $(2{\sim}4{\mu}g/ml)$ of Lb. plantarum NO1 reduced $(40{\sim}60%)$ the urease activity of H. pylori KCCM 41756. Lb. plantarum NO1 inhibited the binding of H. pylori to human gastric cancer cell line, AGS cells, by more than 33%. Lb. plantarum NO1 exhibited high viability (maintained initial viable cell count of $10^9CFU/ml$) in 0.05 M sodium phosphate buffer (pH 3.0) for 2 h, in artificial gastricjuice for 2 h and in 0.3%, 0.5% oxgall for 24 h. Hemolysis phenomena did not observed when Lb. plantarum NO1 was incubated in the blood agar media. We concluded that Lb. plantarum NO1 can be a good candidate as a probiotic, harboring anti-H. pylori activity.

• The Korean Journal of Pesticide Science
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• v.20 no.2
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• pp.83-92
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• 2016

New tree wound-treatment formulations (WTF) were developed in this study. Stimulating effects of plant growth regulating substance on callus formation were evaluated in vivo twig disc culture of Zelkova serrata, Ziziphus jujuba, Pinus densiflora, Ginkgo biloba. and Aesculus turbinata. Based on the evaluation, WTF were prepared with 2,4-D, NAA, and IBA using xanthan gum as an extending agent. WTF were pasted on $2{\times}10cm$ artificial wound on the stem and the effects were evaluated 12 weeks later with the thickness of new callus-tissues. The effects varied with tree species and the growth regulators. In Z. serrata and A. turbinata, 2 mg/L of 2,4-D was the best WTF. In P. koraiensis and G. biloba, 8 mg/L of NAA and 1 mg/L of IBA were the best, respectively. Callus formation was quite lower in G. biloba compared to other species. Stimulating effect of thiophanate-methyl paste was excellent only in Z. serrata and lower than certain WTF in other species. Vaseline, which was used generally as an WTF, remained longer on the wound and causing decay. From the results, it could be recommended that 2,4-D, NAA and IBA were the best WTF for Z. serrata/A. turbinata, P. koraiensis and G. biloba, respectively.

• Journal of Convergence for Information Technology
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• v.8 no.1
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• pp.235-242
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• 2018

The interest about 4th Industrial Revolution was impressively increased from newspapers, iindustry, government and academic sectors. Especially AI what could be felt by the skin of many peoples, already overpassed the ability of the human's even in creative areas. Namely, now many people start fo feel that the effect of the revolution is just infront of themselves. There were several issues in this trend, the ability of deep learning by machine, the identity of the human, the change of job environment and the concern about the social change etc. Recently many studies have been made about the 4th industrial revolution in many fields like as AI(artificial intelligence), CRISPR, big data and driverless car etc. As many positive effects and pessimistic effects are existed at the same time and many preventing actions are being suggested recently, these opinions will be compared and analyzed and better solutions will be found eventually. Several educational, political, scientific, social and ethical effects and solutions were studied and suggested in this study. Clear implication from the study is that the world we will live from now on is changing faster than ever in the social, industrial, political and educational environment. If it will reform the social systems according to those changes, a society (nation or government) will grasp the chance of its development or take-off, otherwise, it will consume the resources ineffectively and lose the competition as a whole society. But the method of that reform is not that apparent in many aspects as the revolution is progressing currently and its definition should be made whether in industrial or scientific aspect. The person or nation who will define it will have the advantage of leading the future of that business or society.

• The Korean Journal of Mycology
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• v.22 no.2
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• pp.145-152
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• 1994

In order to investigate the cultural characteristics of Lentinus lepideus, media, pH, carbon sources, nitrogen sources, vitamin and organic acids were tested in submerged culture. It grew well in GPB(broth), and the optimum temperature and pH was $25^{\circ}C$ and 4.2, respectively. The carbon sources such as galactose belong to monosaccharide and maltose belong to disaccharide were effective for mycelial growth. Peptone which is compound nitrogen source was good for mycelial yield but the other nitrogen sources were not effective. Among the various vitamins, pyridoxine is suitable for mycelial yield. Among the various organic acids, citric acid promoted the mycelial yield but acetic acid interrupted the mycelial growth of L. lepideus.

• Korean Journal of Ichthyology
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• v.12 no.1
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• pp.46-53
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• 2000

Artificial gonadal maturation and spawning inducement of striped knife-jaw Oplegnathus fasciatus were studied. Effects of water temperature and photoperiod under different regims on gonadal activity and maturation of three years old O. fasciatus were investigated histologically. In experiment I (Exp. I), water temperature was gradually increased from $14.5^{\circ}C$ to $21.0^{\circ}C$ and photoperiod was also gradually increased from 10 : 30 L to 15 : 30 L from December 1996 to February 1997 and this conditions were maintained till April. In experiment II (Exp. II), water temperature was increased in the same way from Exp. I and photoperiod was controlled as natural condition till early March and then increased to 15 : 30 L immediately. Control fish were reared in net-cage culture system in the sea from December 1996 to April 1997. Gonadal activity was initiated by increasing water temperature in both Exp. I and II from January. In Exp. I, gonadal maturation and spawning were induced from February when water temperature and photoperiod reached at $21.0^{\circ}C$ and 15 : 30 L, respectively. In Exp. II, complete gonadal maturation was not induced until early March but after treated by compensatory long photoperiod (15 : 30 L), the gonad was matured and subsequently spawning occurred.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.333-342
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• 2010

For the energy-saving production of fresh vegetables in poor environment such as the Antarctic, a container-type plant factory was designed and developed. To maximize space usage of the 20 feet container ($L5.9m{\times}W2.4m{\times}H2.4m$), a three-level hydroponic cultivation system was installed and the nutrient solution was supplied by bottom watering. Using this system, 3 lettuce cultivars were grown under different the light source (light intensity). After 2 weeks from the transplanting, fluorescent lamp ($145\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) showed the best fresh weight of top part and leaf area. However, After 4 weeks, fluorescent lamp plus metal halide lamp ($150\;{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) led to the optimum growth of the each lettuce cultivar. The cultivar, 'Cheongchima', showed the best fresh weight of top part and leaf area, followed by 'Jeokchukmyeon' and 'Lollo rosa'. The chlorophyll concentrations (SPAD) showed no significant difference among the sources of lights. However, 'Cheongchima' showed relatively high chlorophyll concentration. With the above results, we found that the growth of lettuce is depend on light intensity and even at same intensity, the growth is different among the cultivars. Therefore, the selection of optimum cultivar should be considered in the plant factory system that has only weak light density.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.297-300
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• 2017

Plant factory can control artificially the environments for crop cultivation, so they can produce high quality agricultural products all year round. This study was carried to select suitable kohlrabi cultivar for hydroponics in a closed-type plant factory system. We used three cultivars of red kohlrabi, 'Asac kohl', 'Kolibri', and 'Purple king' as plant materials. The artificial light source was LED light, light intensity and photoperiod were $249{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and 12/12 hours (day/night period), respectively. Hydroponic cultivation type was used circulating deep flow technique. At 43 days after transplanting, fresh weight of whole plant and tuber and leaf area were not significantly different among cultivars. Shoot dry weight and tuber dry weight were highest in 'Asac kohl' cultivar, and number of leaves was highest in 'Purple king' cultivar. Sugar content and yield were highest in 'Asac kohl' cultivar. Considering the growth and marketable yields, 'Asac kohl' was the optimal kohlrabi cultivar for hydroponic cultivation in a closed-type plant factory system.

• Journal of Mushroom
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• v.5 no.2
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• pp.76-80
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• 2007

After bottle culture of Pleurotus eryngii, media were taken out the bottle and normally utilized compost. However, nutritional elements were remained in the waste media. This study was carried out to investigate the reusable possibility and the optimal additive rate of waste media in an artificial cultivation of Pleurotus eryngii. The pH had tendency to decrease as the waste media was added from 6.0 to 4.8. Based on the additive rate of 10, 20, 30, 40, and 50%, each treatment waste media was added to new media for culturing Pleurotus eryngii. Among various treatments, the mycelial growth and primordia formation of Pleurotus eryngii were more favorable in the addition of 10-30% waste median than in the addition of 40 and 50%. The yield of its fruiting body was increased slightly in the treatment of 10-30% waste media.