• 펄프종이기술
• /
• 제43권4호
• /
• pp.67-75
• /
• 2011

Sulfuric acid hydrolysis is a typical approach for producing cellulose nanocrystals. The method has been widely used, but it has a disadvantage of low yield of cellulose nanocrystals compared to mechanical method. To expand the application of cellulose nanocrystals in practical, we should be able to produce them with higher yield and the controlled properties. In this study, therefore, we intended to investigate the effect of sulfuric acid hydrolysis condition on the characteristics of the prepared cellulose nanocrystals. The concentration of sulfuric acid, temperature and hydrolysis time were varied, and the yield as well as diverse properties including the morphology, size and zeta potential were examined. We could obtain cellulose nanocrystals up to 70% of yield and found that the properties were dependent on the reaction condition. It would be helpful to select an appropriate condition for producing cellulose nanocrystals.

• 한국미생물·생명공학회지
• /
• 제23권6호
• /
• pp.687-694
• /
• 1995

Alkalophilic Bacillus sp. HJ-12 producing $\beta $-1, 4-D-arabinogalactanase was isolated from soil in the alkalic condition, pH 10.0. $\beta $-1, 4-D-arabinogalactanase was maximaly produced in the medium consisting of 2% soybean arabinogalactan (SAG), 0.5% yeast extract, 0.5% polypeptone, 0.5% NaCl, 0.1% K$_{2}$HPO$_{4}$, 0.02% MgSO$_{4}$$\cdot $7H$_{2}$O, 0.1% Na$_{2}$CO$_{3}$ under the aerobic condition (pH 8.2). $\beta $-1, 4-D-arabinogalactanase is inducible enzyme so that its activity has been increased 10 fold in the SAG medium than in the glucose medium. Through the ammonium sulfate precipitation, DEAE- Sephadex A-50 ion chromatography, and Sephadex G-75 gel chromatography procedures, this enzyme was purified with a single protein of 11% vield and 110 fold's purity. $\beta $-1, 4-D-arabinogalactanase is endo type enzyme producing ollgosaccharide from SAG.

• 대한생식의학회:학술대회논문집
• /
• 대한불임학회 2006년도 The 5th Biannual Meeting of Pacific Rim Society for Fertility and Sterility
• /
• pp.50-52
• /
• 2006

• 말소리와 음성과학
• /
• 제2권3호
• /
• pp.23-27
• /
• 2010

The purpose of this study was to find how English vowels /a, e, i, o, u/ affect the production of English labials /p, b, f, v/ by Korean learners of English. Sixty syllables were composed by five vowels and four labials in the syllable types CV, VC, and VCV. The nonsense syllables were produced three times by nine subjects. The major results show that (1) in inter-vocalic position, the subjects had higher scores in producing /v/ composed with /a, e, o/ and /u/, while subjects had lower scores in producing /p/ with /i/ and /o/, (2) in post-vocalic position, the subjects had higher scores in producing /v/ and /f/ with /a, e/, and /o/, while subjects had lower scores in producing /b/ with /e/ and /i/, and (3) in pre-vocalic position, the subjects had higher scores in producing /v/ with /e, o, u/ and /f/ with /u/, while subjects had lower scores in producing /b/ with /e/, /i/ and /u/. The results suggest that on the whole, Korean learners of English have much difficulty in producing /p/ with /i/ in inter-vocalic condition and /b/ with /i, /e/ in pre-vocalic position.

• 한국축산식품학회지
• /
• 제30권5호
• /
• pp.804-810
• /
• 2010

This study was performed to select protease-producing Bacillus sp. as a potential probiotic starter for fermented meat products. In order to isolate protease-producing bacterium from meju, measured the diameter of the clear zone on agar plate (TSA, 1% (w/v) skim milk) and analyzed for intracellular protease activity, then 10 Bacillus-like strains were isolated. Three Bacillus-like strains (P19, P27, and P33) among 10 strains were able to tolerate in acidic condition (TSB, pH 2.5, 2 h incubation). These 3 strains were showed antimicrobial activity against food-borne pathogenic bacteria. These vegetative cells of 3 strains were showed a survival rate of 0.04% to 0.08% under the artificial gastric acidic condition (TSB, pH 2.5 with 1% (w/v) pepsin), but spore-forming cells were 56.29% to 84.77%. Vegetative cells of 3 strains were the least bile-resistant, while spore-forming cells of 3 strains showed higher survival rate more than 76% under artificial bile condition (TSB, 0.1% (w/v) oxgall bile). In these strains, P27 strain was finally selected as a good probiotic strain. P27 strain was tentatively identified as Bacillus amyloliquefaciens by API CHB kit and 16S rDNA sequence analysis. The results of this study suggest that B. amyloliquefaciens P27 can be used as a potential probiotic starter for fermented meat product.

• 한국당과학회:학술대회논문집
• /
• 한국당과학회 2006년도 제1회 연례학술대회
• /
• pp.37-37
• /
• 2006

• 한국염색가공학회:학술대회논문집
• /
• 한국염색가공학회 2008년도 제39차 학술발표회
• /
• pp.147-148
• /
• 2008

This is studied about the development of new PET yarn having the new appearance and touch effect of Polyester(PET) Yarn as using spinning and texturing technology. The spinning technology is that we use the manufacturing technology caused to the denier difference of filaments composing of yarn. And the texturing technology is that we develope texturing condition caused to spun yarn effect as using filaments producing from the spinning processing.

• 한국작물학회지
• /
• 제56권3호
• /
• pp.205-211
• /
• 2011

가정용 소량의 볶음용 참깨 최적 볶음온도 및 시간은 팽창율, 색도, 착유량, 관능평가 등을 고려해 보았을 때 $220^{\circ}C$ 에 3분간 처리가 적당하였고, 참기름용 최적 볶음온도 및 시간은 $220^{\circ}C$에 5분간 처리가 가장 적당한 것으로 나타났다. 볶음처리 조건시험에서는 변온처리 효과는 고정온도 처리보다는 적은 것으로 나타났으며, 고정온도 처리가 볶음참깨 및 참기름 가공에 적합한 것으로 사료되었다. 가공용 대용량의 볶음참깨 볶음온도는 흰깨, 검은깨 모두 $240^{\circ}C$에 15분간 처리가 총평에서 가장 높은 평점을 받아 대용량으로 참깨를 볶아서 가공할 때는 소량으로 볶았을 때 보다 $20^{\circ}C$정도 더 높은 온도처리가 적절한 것으로 사료되었다. 대용량의 참기름 가공용으로 사용하기 위한 대용량 참깨 복음온도는 흰깨는 $280^{\circ}C$에 10분간 처리가, 검정깨는 $260^{\circ}C$에 15분간 처리가 총평에서 가장 높은 평점을 얻었고, 검정깨 보다는 흰깨는 더 높은 온도로 처리되어야 함을 알 수 있었다.

• 한국미생물·생명공학회지
• /
• 제27권5호
• /
• pp.399-403
• /
• 1999

For the production of trehalose, microorganisms capable of producing trehalose extracellularly were screened from the stock cultures in our laboratory. among them, Micrococcus luteus IFO 12708 showed the highest productivity of trehalose. For the increase of productivity, the mutant strai Hs-208 having higher trehalose production was selected with NTG(N-methyl-N'-nitrosoguanidine) mutagenesis, which led to the decrease of the specific activity of trehalose phosphorylase(3.2-fold) as compared to the wild strain. The optimum condition for the trehalose production was established as follows: 20g/l of glucose and 6g/l of tryptone were used as a sole carbon source and nitrogen source, respectively, and cultivations were carried out at 3$0^{\circ}C$ and pH 6.0. After 20hrs cultivation, addition of 20unit/ml penicillin G led to the higher conversion yield of trehalose. Under the optimum condition, 6.547g/l trehalose was produced with conversion yield of 32.7%.

• 한국미생물·생명공학회지
• /
• 제20권4호
• /
• pp.395-400
• /
• 1992

토양으로부터 cholesterol oxidase 생산성이 있는 균주를 분리하고, 이들 분리된 균주들로 부터 여러 단계의 균주 선발 실험을 통하여 cholesterol oxidase 생산성이 가장 우수한 미생물을 선별하여 HSL613이 라고 명명하였다. 이 HSL613은 $37^{\circ}C$에서 보다 $30^{\circ}C$에서 배양했을 때 더 높은 효소생산성을 나타내었고 배양시간이 경과함에 따라 pH가 높아지면서 효소생산이 증가하여, 144시간 배양하였을 때 pH는 8.5로 높아졌고 효소생산량도 가장 높았다. 균체량은 120 시간 배양하였을 때 가장 많았다. 본 실험에서 HSL613의 효소생산조건을 검토한 결과 최적 배지조성은 2.0% glucose, 2.0% yeast extract, 0.2% $K_2HP0_4$, 0.1% NaCl. 0.005% $CaCl_22H_2O, 0.001% $FeSO_47H_20$ 로 판명되었으며, $30^{\circ}C$에서 144시간 (6일때) 배양하였을 때 효소생성이 가장 많았고 (10.3U/ml), 종균의 접종량은 1.0%(v/v)일때가 가장 효소생성이 잘 되었다.