• 생명과학회지
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• 제6권2호
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• pp.135-141
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• 1996

양식을 위한 먹이사료로서 가능성 있는 효모균주를 연구하였다. Kluyveromyces fragilis효모와 Candida utilis 효모의 최대 비증식 속도와 바이오매스 효율은 Saccharomyces cervisiae 효모에 비하여 굉장히 높은 값을 나타내었다. 따라서, 이 연구는 대량생산을 위하여, 플라스크 배양을 통한 이들 두 효모균들의 성장특성에 그 초점을 맞추었다. 5% 접종량을 가지고 실험한 결과, 가장 좋은 $\mu$$_{max}$ 와 OD$_{max}$ 값들은 K, fragilis는 2.5% fructose 배지에서, C. utilis는 2% YE배지에서 각각 얻었으며, 이 때의 이 값들은 K. fragilis는 0.73 hr$^{-1}$1 와 3.00을 C. uitilis는 0.59 hr$^{-1}$ 와 2.80으로 밝혀졌다. 또한, 아연과 염의 초기종도가 증가할수록 균성장에 있어서의 우도기는 증가하였으며, 접종량이 증가할수록 유도가는 감소하였다. 두 효모균은 3.5% 염농도에서 비교적 잘 자랄 수 있었으며, C. utilis 효모균만이 아연을 이용할 수 있었다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.337-342
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• 2006

The use of GPS receiver at outer space becomes common in low earth orbit. The KOrea Multi-Purpose SATellite-1 (KOMPSAT-1) which was launched in December 1999 has used GPS receiver's navigation solution to perform the Orbit Determination (OD) in the ground. At the circumstance of using only one ground station, the Orbit Determination using GPS receiver is good method. Because the accuracy of navigation solution acquiring directly from GPS receiver is not enough in satellite application such as map generation, post-processing concepts such as the Precise Orbit Determination (POD) are applied to satellite data processing to improve satellite position accuracy. The POD uses GPS receiver's raw measurement data instead of GPS receiver's navigation solution. The KOrea Multi- Purpose SATellite-2 (KOMPSAT-2) system newly uses the POD technique for large scale map generation. The satellite was launched in the end of July 2006. The satellite sends high resolution images in panchromatic band and multi-spectral bands to the ground. The satellite system uses GPS receivers as source of time synchronization and command reference in the satellite, provider of navigation solution for the OD, and provider of raw measurement data for the POD. In this paper, mechanical configuration and operations of the GPS receiver will be presented. The GPS data characteristics of the satellite such as time synchronization, command reference, the OD using GPS receiver's navigation solution, and the POD using GPS receiver's raw measurement data will be presented and analyzed. The enhancement of performance compared with it of the previous satellite will also be analyzed.

• Bulletin of the Korean Chemical Society
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• 제20권12호
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• pp.1451-1456
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• 1999

Solvolyses of α-methoxy-α-(trifluoromethyl)phenylacetyl chloride in H₂O, D₂O, CH₃OD, 50% D₂O-CH₃OD, and in aqueous binary mixtures of acetone, dioxane, ethanol and methanol are investigated at 25.0℃. The Grunwald-Winstein plots of first-order rate constants for α-methoxy- α-(trifluoromethyl)phenylacetyl chloride with $Y_{Cl}$ show a dispersion phenomenon. Solvent nucleophilicity N has been shown to give considerable im-provement when it is added as an 1N term to the original Grunwald-Winstein for the solvolyses of α-methoxy- α-(trifluoromethyl)phenylacetyl chloride. The dispersions in the Grunwald-Winstein correlations in the present studies are caused by solvent nucleophilicity. The magnitude of l and m values associated with a change of solvent composition predicts the associative $S_N2$ transition state. The kinetic solvent isotope effects determined in deuterated water and methanol are consistent with the proposed mechanism of the general base catalyzed associative $S_N2$ or $S_AN$ mechanism for the of α-methoxy- α-(trifluoromethyl)phenylacetyl chloride.

• 치위생과학회지
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• 제23권1호
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• pp.51-59
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• 2023

Background: Tea tree oil has antiviral, antimicrobial and antifungal effects and Mastic oil has antifungal and anticancer effects. For synergistic effects of oils, blending oil containing a mixture of two to three oils is recommended. This study aimed to determine the antibacterial effects of Tea tree oil, Mastic oil, and Blending oil containing the two oils in a mixture, to verify and suggest the potential use of these oils as a substance to prevent dental caries. Methods: Tea tree oil, Mastic oil, and Blending oil with a 1:1 blend of the two oils were diluted in liquid medium to 0% (negative control), 0.5%, 1.0%, and 2.0%. Streptococcus mutans was applied to each experimental group of the three diluted oils and after 8 h culture, the optical density (OD) was measured and the growth inhibition rate for S. mutans was estimated. Results: Tea tree oil had significantly low OD values across all concentrations (p<0.05) without significant variation among different concentrations (p>0.05). Mastic oil did not significantly vary in OD compared to the negative control across all concentrations (p>0.05) without significant variation among different concentrations (p>0.05). Blending oil, compared to the negative control, did not significantly vary in OD at 0.5% (p>0.05) but significant variation was found as the concentration increased (p<0.05). Additionally, for Tea tree oil and Mastic oil, the growth inhibition rate showed no significant variation according to concentration (p>0.05), whereas for Blending oil, the growth inhibition rate for S. mutans showed a significant difference at 1.0% (p<0.05) and at higher concentrations. Conclusion: Blending oil containing a Tea tree oil and Mastic oil demonstrated a significant growth inhibition effect on S. mutans from the concentration of 1.0%, which suggested its potential use as an effective antibacterial agent for dental caries.

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.1963-1967
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• 2010

The rates of solvolysis of 4-morpholinecarbonyl chloride (MPC) have measured at $35.0^{\circ}C$ in water, $D_2O$, $CH_3OD$, and in aqueous binary mixtures of acetone, ethanol, methanol, and 2,2,2-trifluoroethanol. An extended (two-term) Grunwald-Winstein equation correlation gave sensitivities towards changes in solvent nucleophilicity and solvent ionizing power as expected for a dissociative $S_N2$ and/or $S_N1$(ionization) pathway. For nine solvents specific rates were determined at two additional temperatures and higher enthalpies and smaller negative entropies of activation were observed, consistent with the typical dissociative $S_N2$ or $S_N1$(ionization) pathway. The solvent deuterium isotope effect values for the hydrolysis of MPC of $k_{H_2O}/k_{D_2O}$ = 1.27 and for the methanolysis of MPC of $k_{MeOH}/k_{MeOD}$ = 1.22 are typical magnitudes of the $S_N1$ or ionization mechanism.

• 대한수의학회지
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• 제35권1호
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• pp.87-94
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• 1995

Western immunoblot analysis of antigen of T sergenti merozoite revealed that the immunodominant proteins of this organism were characterized as the 18KD, 29KD, 34KD, 45KD and 105KD in Korea. The 34KD and 45KD among those immunodominant proteins of the parasite were isolated and their amino acid sequences from the $NH_2$-terminus were determined and synthesized. They respective polypeptides were cationized to enhance their antigenicity, fortified with Freund's adjuvant and tested for immunogenicity in rabbits and cattle. The results obtained were as follows; 1. Theileria sergenti merozoite antigen was shown in 120KD, 100KD, 66KD, 45KD, 34KD and 30KD in western immunoblot using serum of rabbits immunized with 34KD synthetic polypeptide and 70KD, 58KD, 55KD and 45KD using bovine serum. In western immunoblot, 45KD, 34KD and 30KD were recognized by immunized rabbits, and 50KD and 45KD by cattle sera immunized with 45KD synthetic polypeptide, respectively. 2. The ELISA utilizing the synthetic polypeptides demonstrated significant antibody response to the respective peptides. After the 2nd booster injection, an OD of 0.760(preimmunization 0.132) in rabbits and an OD of 0.645(preimmunization 0.488) to 34KD synthetic polypeptide in cattle were observed. In animals immunized with 45KD synthetic polypeptide, after the 2nd booster injection, an OD of 0.640(preimmunization 0.144) in rabbit, and an OD of 0.776 (preimmunization 0.477) in cattle were measured. 3. After the 2nd booster the reciprocal IFA titer was 1:64 in rabbits and 1:512 in cattle immunized with the 34KD synthetic polypeptide. The IFA titre was observed as 1:512 in rabbit and 1:1,024 in cattle in immunized with the 45KD synthetic polypeptide.

• 한국미생물·생명공학회지
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• 제16권2호
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• pp.131-135
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• 1988

Lactobacillus acidophilus KFCC12731과 Saccharomyces cerevisiae KFCC32017을 두유 배지에 접종하여 산생성 조건을 검토하였다. L. acidophilus를 단독배양하는 것보다 S. cerevisiae와 혼합배양하는 것이 산생성이 많았다. 이 두 균을 대두유 배지에 혼합배양하였을 경우 최적조건은 다음과 같았다. 두유에 sucrose를 1,5% 또는 skim milk를 2.0~3.0% 첨가하고 L. acidophilus와 S. cerevisiae의 접종비율은 OD 600 값으로 3 : 7~8 : 2가 되게 접종하여 34$^{\circ}C$에서 12시간 이상 배양할 때 산생성이 최대가 되었다.

• 한국식품저장유통학회지
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• 제9권4호
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• pp.425-428
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• 2002

Genus Monascus(M. pilosus and M purpureus)의 배지(Lin, SP, YM YE, GMIN, SMO, MY, GY, Nishikawa, sucrose, stock culture, Mizutani, modified Lit Toya 및 쌀배지)에 따른 균의 증식도와 색소생성량을 조사하였다. M. pilosus 및 M purpureus의 증식도가 높은 배지는 Mizutani 배지와 Lin 배지 였으며 3$0^{\circ}C$에서 10일간 배양하였을 때 생균체 무게는 각각 24.5~26.9 g/100 mL 및 15.9~17.2 g/100 mL이였고 M. pilosus의 성장률이 높았다. 색소생성량이 높은 배지는 두 균주 다같이 Lin 및 Mizutani 배지였으며 각각 흡광도는 1.2~1.6 및 0.8~l.0이었다. 균주 중에서는 M. pilosus에서 높았다.

• 한국식품과학회지
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• 제40권2호
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• pp.178-183
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• 2008

삼투건조와 진공주입에 의한 사과의 물질이동 특성과 열풍건조 시 건조특성, 그리고 제조한 사과 건조제품의 품질을 비교하였다. 삼투건조 시 사과 시료의 중량이 감소하고 수분손실이 증가한 반면 진공주입 시에는 중량이 증가하고 수분손실이 감소하였으며, 진공주입 시 고형분 증가가 컸다. 50$^{\circ}C$에서의 열풍건조시 건조시간에 따른 사과 시료의 수분함량 변화를 Page model에 적용하여 지수 n, k 및 건조시간을 산출하였다. 건조시간이 대조구의 4.45 hr에서 삼투건조 시 5.82 hr, 진공주입 시 6.38 hr로 증가하는 반면 k는 대조구의 0.456 $hr^{-1}$에서 각각 0.326 $hr^{-1}$과 0.277 $hr^{-1}$로 감소하였으며, n은 대조구의 0.938에서 각각 0.754와 0.950으로 변화하였다. 삼투건조 및 진공주입한 사과 건조제품의 품질을 대조구와 비교하였다. 삼투건조에 의해 건조제품의 수축도와 복원력이 대조구에 비해 크게 감소한 반면 압착력이 크게 증가하였고 적정산도와 ascorbic acid의 함량이 크게 감소하였다. 진공주입에 의해서는 대조구에 비해 수축도와 압착력이 증가하였다. 복원한 사과 건조제품에 대한 관능적 기호도 측정 결과 삼투건조한 사과 건조제품이 외관, 조직감, 종합적인 기호도 등의 모든 관능검사 항목에서 유의적으로 높은 기호도를 나타내었고, 건조상태에서의 관능적 기호도 측정 결과에서는 진공주입한 사과건조제품이 모든 관능검사 항목에서 유의적으로 높은 기호도를나타내었다.

• 유기물자원화
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• 제15권2호
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• pp.128-135
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• 2007

음식물폐수, 축산폐수, 지렁이 등, 다양한 분리원으로부터 음식물류폐수내 섬유소, 지방, 단백질 등 유기 성분을 처리하기 위한 유기물분해 미생물을 분리하여 그 특징을 밝히고 균주를 동정하였다. 음식물류폐수에서 분리된 6종의 균주를 비롯하여 음식물폐수내 삼성 유기물에 대한 분해능이 우수한 11균주를 최종적으로 분리하여 동정하였다. 분자생물학적 동정결과, 9종은 Bacillus 속으로 밝혀졌고, 2종은 Enterobacter 속 및 Pantoea agglomerans로 동정되었다. 유기물분해효소 활성도 조사결과, 음식물폐수로부터 분리된 FWB-5 (Bacillus pumilus)와 FWB-6 (B. lichenisformis) 및 축산폐수로부터 분리된 OD-4 (Pantoea agglomerans)의 균주에서 섬유소에 대한 효소활성이 가장 높게 나타난 것을 비롯하여 전체적으로 효소활성도가 높게 나타났다. FWB-5 및 OD-4의 경우, 효소활성을 위한 최적 생장온도 및 pH는 각각 $37^{\circ}C$ 및 7.0으로 나타났으며, FWB-6의 경우, $25^{\circ}C$에서 단백질 및 지질에 대한 효소활성도가 높게 관찰되었다.