• Journal of the Korean Applied Science and Technology
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• v.26 no.4
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• pp.422-427
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• 2009

We have investigated the effects of polyols and NaCl on the rheological behaviours of surfactant mixtures. Sodium lauryl ether sulfate (SLES), cocamidopropyl betaine (CAPB), disodium cocoamphodiacetate (DSCA), cocamide DEA (CDEA) and lauroyl/myristoyl DEA (LMDE) were used as surfactants. The polyols added into the surfactant mixture were 1,3-butylene glycol, propylene glycol, glycerin, sorbitol, dipropylene glycol, PEG 1500 and PEG 400. The addition of amphoteric surfactant to SLES aqueous solution lead to increase the height of foam and the viscosity of the system. The addition of nonionic surfactant, LMDE or CDEA to the SLES aqueous solution increased the viscosity and the effect of LMDE was better than that of CDEA. The effect of adding polyols and NaCl into the surfactant mixture aqueous solution lead to increase or decrease the viscosity of the systems depending on the concentration of NaCl and the kinds of polyols. These results can be explained through the salting in or salting out of surfactant of the systems.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.511-516
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• 2005

Sorbitan methacrylate was synthesized from sorbitan dehydrated from D-sorbitol using an immobilized lipase. To optimize the enzymatic synthesis of sorbitan methacrylate, response surface methodology was applied to determine the effects of five-level-four-factors and their reciprocal interactions on sorbitan methacrylate biosynthesis. A total of 30 individual experiments were performed, which were designed to study reaction temperature, reaction time, enzyme amount and substrate molar ratio. A statistical model predicted that the highest conversion yield of sorbitan methacrylate was 100%, at the following optimized reaction conditions: a reaction temperature of 43.06 $^{\circ}C$, a reaction time of 164.25 mins., an enzyme amount of 7.47%, and a substrate molar ratio of 3.98:1. Using these optimal factor values under experimental conditions in four independent replicates, the average conversion yield reached 98.7%${\pm}$1.2% and was well within the value predicted by the model.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.3
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• pp.376-380
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• 2000

This study was conducted to investigate protein and carbohydrate utilization of Micrococcus varians, Staphylococcus carnosus and Staphylococcus xylosus. Sensitivity to pH, sodium chloride, potassium sorbate and sodium nitrite of these strains was also determined. In Chinese-style beaker sausage manufacturing, the growth rate of these strains during the curing period ($20^{\circ}C$ and $30^{\circ}C$) was evaluated. The results indicated that no strains could hydrolyze azo-casein and sarcoplasmic protein and only S. xylosus could hydrolyze gelatin at $30^{\circ}C$. All of these strains could oxidize and ferment fructose and mannitol. S. carnosus and S. xylosus could slightly oxidize lactose and utilize citrate. Arabinose was oxidized by S. xylosus and sorbitol was oxidized by S. carnosus. Growth of M. varians was restricted at pH 5.0 and S. carnosus and S. xylosus were restricted at pH 4.5. S. xylosus and S. carnosus were able to grow with 0.1~0.5% potassium sorbate, 50~200 ppm sodium nitrite or 1~15% sodium chloride. S. xylosus had a higher growth rate than the other strains. Staphylococcus species grew well during curing period of Chinese-style beaker sausage then followed by Micrococcaceae.

• Journal of Plant Biotechnology
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• v.4 no.2
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• pp.71-76
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• 2002

In order to achieve repetitive somatic embryogenesis in cacao (Theobroma cacao L.), callus derived from floral tissues were continuously cultured in a medium containing 2,4-D. In 5% of the explants, repetitive somatic embryogenesis was observed after 8 weeks and maintained in a globular stage for several weeks. This is the first report showing repetitive somatic embryogenesis in cacao. The calli were bombarded with a plasmid containing $\beta$-glucuronidase (gus) as reporter gene. Two week old calli showed the high average number of cells expressing the us gene. The effect of osmotic agents (mannitol, sorbitol and sucrose) on gene expression was evaluated. Pre-treatment during 16 h with 0.25 M mannitol revealed an improvement in gene expression. The potential utilization of the repetitive embryogenesis, combined with osmotic treatment, is discussed as an alternative to achieve stable transgenic cacao plants.

• Journal of Microbiology and Biotechnology
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• v.26 no.6
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• pp.1087-1097
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• 2016

An intracellular lipase from Anoxybacillus flavithermus HBB 134 was purified to 7.4-fold. The molecular mass of the enzyme was found to be about 64 kDa. The maximum activity of the enzyme was at pH 9.0 and 50℃. The enzyme was stable between pH 6.0 and 11.0 at 25℃, 40℃, and 50℃ for 24 h. The K_m and V_max of the enzyme for pNPL substrate were determined as 0.084 mM and 500 U/mg, respectively. Glycerol, sorbitol, and mannitol enhanced the enzyme thermostability. The enzyme was found to be highly stable against acetone, ethyl acetate, and diethyl ether. The presence of PMSF, NBS, DTT and β-mercaptoethanol inhibited the enzyme activity. Hg²⁺, Fe³⁺, Pb²⁺, Al³⁺, and Zn²⁺ strongly inhibited the enzyme whereas Li⁺, Na⁺, K⁺, and NH₄⁺ slightly activated it. At least 60% of the enzyme activity and stability were retained against sodium deoxycholate, sodium taurocholate, n-octyl-β-D-glucopyranoside, and CHAPS. The presence of 1% Triton X-100 caused about 34% increase in the enzyme activity. The enzyme is thought to be a true lipase since it has preferred the long-chain triacylglycerols. The lipase of HBB 134 cleaved triolein at the 1- or 3-position.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.379-385
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• 2015

The nutritional components of astringent persimmons according to growing region (five different regions) and cultivar (Daebong and Bansi) were analyzed. The analyzed nutritional components were proximate compositions, insoluble and soluble dietary fibers, vitamin C, carotenes (${\beta}$-carotene and lycopene), free sugars (glucose, fructose, and sucrose), sugar alcohols (xylitol, sorbitol, and mannitol), minerals (Na, Mg, K, Ca, Mn, Fe, and Zn), organic acids (tartaric acid, malic acid, citric acid, and succinic acid), tannic acid, total phenolic compounds, and flavonoids. Daebong and Bansi, which are representative cultivars of astringent persimmons grown in Korea, exhibited significant differences in nutritional components. Insoluble dietary fibers, ${\beta}$-carotene, fructose, sucrose, mannitol, potassium, malic acid, succinic acid, and total phenolic compounds were present at higher levels in Daebong as compared to Bansi. On the other hand, Bansi was rich in moisture, crude protein, vitamin C, Ca, Mn, tartaric acid, and flavonoids. Nutritional components were highly influenced by growing region. Daebong grown in region A was greater in ${\beta}$-carotene, sorbitol, mannitol, zinc, and total phenolic compounds among the all other tested persimmons grown in five different regions. The crude protein, Na, Ca, Mn, tartaric acid, and flavonoids were highest in Bansi grown in E region.

• Proceedings of the Korean Society for the Gifted Conference
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• 2003.11a
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• pp.167-169
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• 2003

과학영재 교육의 목적과 효과를 달성하기 위해서는 과학영재들의 특성, 과학영재의 판별이나 교육 프로그램의 개발, 과학영재들의 과학, 과학자, 과학관련 직업에 대한 인식 등 여러 요소들에 초점을 맞추어 연구해야 하며 이를 바탕으로 교육해야 한다. 과학영재교육의 중요한 점 중 하나는 우리가 교육하는 과학영재들이 성장해서 그들의 영재성을 발휘하도록 하는 것에 있다. 이는 국가적으로도 매우 중요한 일이다. 과학기술의 발달과 국가의 발전은 뛰어난 영재들이 기여를 하였으며 그 업적을 통해 국제경쟁 사회를 선도해 나갈 수 있기 때문이다. 과학영재 교육의 성공 기준 중 하나로 노벨상 수상을 기대하는 것이라고 생각할 수 있다. 물론 노벨상만을 목표로 하는 것은 과학영재교육이 왜곡될 수 있으나, 과학영재교육을 통해서 과학 분야에 뛰어난 인재를 양성하고 이들로부터 과학의 수준이 높아지면서 자연스럽게 노벨상을 수상할 수 있을 것이다. 2002년 노벨 과학상에서 일본은 물리학과 화학 두 분야에서 수상자를 배출하였다. 특히 노벨 화학상을 받은 다나카 고이치는 박사학위도 없는 40대의 평범한 회사원이었다. 그는 일본 과학계를 장악하고 있는 유명 국립대학의 교수도 아니고, 수상 발표 뒤 대부분의 일본 화학자들이 누군지 몰라 당황했을 정도로 잘 알려지지 않은 인물이었다. 이러한 사건은 일본인들에게 희망을 안겨주었으며 과학 및 과학자에 대한 관심과 투자에 대한 인식에 있어 많은 변화를 초래하였다. 노벨상 자체가 국가정책의 목표가 될 수는 없지만, 과학자나 국민 개개인들에게 희망이 되는 것은 사실이다. 해마다 노벨상 수상자가 발표되는 시점에서 우리들은 아주 오랫동안 방관자가 되어 왔다. 이제 여러 과학영재교육기관 등을 통해서 과학영재 교육을 효율적으로 실시한다면 조만간 상황이 바뀔 것으로 기대할 수 있다.택한 이유는 첫 번째가 사회 봉사와 국가 발전에 기여하기 위한 것이었으며, 다음으로는 생활의 안정을 꼽고 있었다. 이외에도 과학적 업적 달성을 위해, 자신의 꿈(이상) 실현을 위해 등의 이유를 들고 있었다. 이러한 경향은 남자 영재와 여자 영재들간에 다소 차이는 있었으나 거의 유사한 것으로 조사되었다(Pearson $X^2$=2.186, p>0.05). 우수한 능력을 소유한 영재들이 과학관련 분야를 선호하지 않는다면 우리나라의 과학 발전은 그리 낙관할 수 없을 것이다. 그러므로, 영재들을 과학 관련 분야로 이끌어 그들이 소유한 영재성을 발휘하도록 하는 것은 매우 중요한 일일 것이다. 이룰 위해서는 과학 영재들이 자신의 능력에 대한 자신감을 더욱 높여야 하며 그 능력을 과학관련 분야에 발휘하도록 하기 위한 국가적, 사회적, 교육적 노력이 필요하다. 노력이 필요하다.~42.1mg$CO_2$/kg.hr였으며 12$^{\circ}C$에서 2.5~8.2mg$CO_2$/kg.hr로 일반적으로 보고되고 있는 토마토 호흡속도와 일치하는 결과를 나타내었다.다.환원당인 sucrose 함량은 계속 증가하였고 fructose, glucose, sorbitol의 함량(추황의 sorbitol을 제외)은 생장이 촉진됨에 따라 증가하다가 다시 점차적으로 감소하였다. 이러한 결과는 총당과 환원당의 측정결과와 일치한 것으로 나타났다. 결론적으로 배의 성장에 따라 산 함량은 감소하였고 당 함량은 증가하였다.luco-pyranoside, quercetin 7-O- -glucopyranoside, acacetin 7-O-$\beta$-D-glucuronide and apigenin-6-C-$\beta$

• Journal of Plant Biotechnology
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• v.41 no.4
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• pp.216-222
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• 2014

This study was carried out to develop an efficient transformation protocol via particle bombardment with PLBs (protocorm-like bodies) in Phalaenopsis. To achieve this aim, osmoticum treatment and an increasing shooting chances in particle bombardment process were applied for this study. In addition, pCAMBIA3301: ORE7 vector which contains a herbicide-resistance bar gene as a selectable marker and ORE7 gene as a gene of interests were employed. With regard to the increasing chances of shooting in particle bombardment, double shooting was the best results with 1.5 ~ 2.5 times higher than those of a single or triple shooting treatment in the productioon of PPT (D-L-phosphinothricin)-resistant PLBs. However, regeneration rate of shoots in double shooting was not high as a single shooting. Further, double shooting showed 35 ~ 40% higher than that of a single shooting in the frequency of browning. Regarding effects of different osmotic treatments, combination of 0.2 M sorbitol with 0.2 M mannitol showed the best results in transformation efficiency, regeneration of transformants and reduction of browning. Putative transgenic Phalaenopsis plants were analyzed by PCR analysis and confirmed the presence of bar and ORE 7 gene. Also, real-time PCR was conducted by using 21 transgenic plants and showed only 4 plants had one copy of transgene; whereas, the other 17 plants had more than 2 copies of transgene. Transgenic phalaenopsis plants produced in this study were transferred to pots and flowered normally without morphological variations in flower and leaf.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.391-402
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• 2021

Earthworms play an important role in soil fertilization, interacting continually with microorganisms. This study aims to demonstrate the existence of beneficial microorganisms living in the earthworm's immune system, the coelomic fluid. To achieve this goal, a molecular identification technique was performed, using cytochrome c oxidase I (COI) barcoding to identify abundant endogenic earthworms inhabiting the temperate zone of Rabat, Morocco. Then, 16S rDNA and ITS sequencing techniques were adopted for bacteria and fungi, respectively. Biochemical analysis, showed the ability of bacteria to produce characteristic enzymes and utilize substrates. Qualitative screening of plant growth-promoting traits, including nitrogen fixation, phosphate and potassium solubilization, and indole acetic acid (IAA) production, was also performed. The result of mitochondrial COI barcoding allowed the identification of the earthworm species Aporrectodea molleri. Phenotypic and genotypic studies of the sixteen isolated bacteria and the two isolated fungi showed that they belong to the Pseudomonas, Aeromonas, Bacillus, Buttiauxella, Enterobacter, Pantoea, and Raoultella, and the Penicillium genera, respectively. Most of the isolated bacteria in the coelomic fluid showed the ability to produce β-glucosidase, β-glucosaminidase, Glutamyl-β-naphthylamidase, and aminopeptidase enzymes, utilizing substrates like aliphatic thiol, sorbitol, and fatty acid ester. Furthermore, three bacteria were able to fix nitrogen, solubilize phosphate and potassium, and produce IAA. This initial study demonstrated that despite the immune property of earthworms' coelomic fluid, it harbors beneficial microorganisms. Thus, the presence of resistant microorganisms in the earthworm's immune system highlights a possible selection process at the coelomic fluid level.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.10b
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• pp.21-21
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• 2003

An efficient plant regeneration system was developed for Hordeum vulgare L. cv Baegdong - an important Korean cultivar. The protocol was based on a series of experiments involving the sizes of mature embryos and the culture media. The embryo size is found to be critical for the establishment of embryogenic callus. Embryos of 1.1-1.5 mm size showed a much higher ability to produce embryogenic callus capable of regenerating green plants. The auxins picloram and dicamba proved effective in inducing callus from mature embryos. 2.5 mg $I^{-1}$ dicamba and 4.0 mg $I^{-1}$ picloram in Murashige and Skoog's (MS) medium was optimum for the induction of primary callus. The induced primary callus was loose and friable which ultimately developed into creamy white and compact callus after transferring into the fresh medium. Multiple shoots were induced in the MS medium supplemented with 6.0 g $I^{-1}$ maltose, 20 mg $I^{-1}$ sorbitol, 0.5 mg $I^{-1}$ 2,4-D and 1.0 mg $I^{-1}$ kinetin and the rate was 6.5 shoots per embryo. Regenerated plants were hardy and developed roots rapidly in the medium containing 0.2 $I^{-1}$ IBA. This efficient plant regeneration system provides a foundation for generating transgenic plants of this important barley cultivar.