• 생명과학회지
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• 제13권6호
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• pp.794-798
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• 2003

라세믹 phenyl oxirane 기질에 대한 asymmetric biohydrolysis 활성이 우수한 Rhodosporidium toruloides SJ-4를 생촉매로 이용하여 입체선택적 가수분해 반응을 통해 라세믹 phenyl oxirane 기질로부터 광학활성 (S)-phenyl oxirane를 회분식으로 생산하는 실험을 수행하였다. (R)-phenyl oxirane 이성질체에 대한 초기 가수분해 속도에 영향을 주는 실험인자들인 pH, 반응온도, DMSO cosolvent 첨가량 등에 대해 중심합성계획법을 이용한 반응표면 분석을 통해 가수분해반응 속도를 향상시킬 수 있는 최적 반응조건을 결정하였다. pH 7.4, 반응온도 34℃ 및 DMSO 첨가량 2.3%(v/v)의 조건에서 라세믹 기질 초기 농도 100mM로부터 약 10시간 정도의 반응을 통해 ee 값이 100%인 광학적으로 순수한 (S)-phenyl oxirane를 24% 정도 (이론수율 = 50%)의 높은 수율로 얻을 수 있었다. ^u Batch production of (S)-phenyl oxirane was investigated using epoxide hydrolase activity of Rhodosporidium toruloides SJ-4. Effect of reaction condition of asymmetric biohydrolysis of racemic phenyl oxirane was analyzed and optimized by response surface methodology. The optimal conditions of pH, temperature and DMSO cosolvent ratio were 7.4, 34 ℃, and 2.3%(v/v), respectively. The final yield was enhanced up to 67%, and reaction times required to reach 99% ee (enatiomeric excess) decreased down to 50% by response surface methodology Enantiopure (S)-phenyl oxirane with 100% enantiopurity and 24% yield (theoretical yield = 50%) was obtained from racemic substrate.

• 한국식품과학회지
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• 제31권5호
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• pp.1211-1215
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• 1999

마늘을 물로 추출할 때 효소분해와 pH, 그리고 유기산, 유기 또는 무기염의 첨가가 추출액의 고형분 수율과 색에 미치는 영향을 조사하였다. 그 결과 상업적다당류 분해효소에 의한 가수분해는 고형분 수율을 $15{\sim}20%$ 증가시켰으나 녹변현상이 더 발생하였고 노란색과 밝기가 감소되었다. 추출시 pH의 조정은 수율에는 큰 영향이 없었지만, $4.4{\sim}5.0$의 범위에서 녹색의 강도가 증가되어 적절치 않았다. 여러가지의 염과 유기산의 첨가 결과, $CaCl_2$와 sodium oxalate, tartaric acid, phosphoric acid가 수율 향상에 효과적이었으며, $K_{4}P_{2}O_{7}$은 수율향상과 녹변방지에 효과가 있었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권1호
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• pp.67-71
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• 2004

Ten improved mulberry varieties (Vl, C1730, C2016, C2017, Anantha, RFS-175, Thallaghatapura, Vishala, S1 and S1635) were evaluated through enzyme assay and estimation of soluble protein content followed by regression analysis, grown under irrigated conditions in the alluvial soils of Gangetic plains of West Bengal in India for five successive crops in a year, The nitrate reductase (EC No. 1.6.6.1) activity (NRA, $\mu$mol N $O_2$- $h^{-1}$ $g^{-1}$ fr, wt.), total soluble protein (mg $g^{-1}$ fr, wt.) was estimated which showed to vary significantly in the tested varieties. In addition to these, the other parameters like unit leaf fresh and dry weight (g), moisture ％, unit leaf area ($\textrm{cm}^2$), specific leaf weight (g c $m^{-2}$ ), total soluble sugar (mg $g^{-1}$ fr, wt.), leaf yield/plant (kg), shoot yield/plant (kg) and net photosynthetic rate (NPR, $\mu$㏖ $m^{2}$ $s^{-1}$ ) were also studied which showed to vary significantly in tested varieties. Among them, S1635, haying higher NRA (13.25 $\mu$㏖ N $O_2$- $h^{-l}$ $g^{-1}$ fr, wt.), total soluble protein (39.63mg $g^{-1}$ fr, wt.), NPR(16.66 $\mu$㏖ $m^{-2}$ $s^{-1}$ ), total soluble sugar (48.44 mg $g^{-1}$ fr. wt.), leaf yield/plant (0.689 kg) and shoot yield/plant (1.135 kg) showed its superiority over other tested varieties. Regression and correlation coefficients were analysed, and a strong positive correlation was found between NRA ＆ total soluble protein, NRA ＆ NPR, NRA ＆ total soluble sugar, NRA af unit leaf weight, NRA ＆ specific leaf weight, NRA ＆ leaf yield/plant, NRA ＆ shoot yield/plant, NPR ＆ leaf yield and NPR ＆ specific leaf weight.t.

• ALGAE
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• 제21권3호
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• pp.317-321
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• 2006

The effects pH and salinity on the brown alga Sargassum fulvellum were investigated in the context of the removal of two major associated animals, Caprella scaura and Gammaropsis utinomi. Optimum quantum yield (Fv/Fm) of S. fulvellum was also examined in the same experimental conditions as an index of stress. Experiments on pH and salinity tolerances of the two animal species indicated that mortality was more than 80% at extremes of pH (2, 3, 4, 10, 11, 12) and salinity (0, 3.5, 7, 10, 44 psu) after a 5 min treatment. Lethal time (LT50) from pH 2 to pH 4 was less than 90 sec in C. scaura, and less than 70 sec in G. utinomi. From 0 to 10 psu, LT50 was less than 20 sec in C. scaura and less than 60 sec in G. utinomi. The quantum yield of S. fulvellum was not significantly different from controls within the pH range 4~10, and within the salinity range of 7-40 psu. When exposed to pH and salinity conditions outside these ranges, the effect of these factors on the removal of two animal species was higher, but quantum yield was highly reduced. These results indicate that the optimal conditions for removing the animal species without affecting optimum quantum yield were pH 4-10, and salinities 7-10 psu and 44 psu.

• 한국작물학회지
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• 제42권1호
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• pp.56-60
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• 1997

인공산성비를 처리하였을 때 작물이 입는 피해양상 상호간의 관계를 알아보기 위하여 벼(일품벼), 콩(만리콩), 감자(대지), 고추(풍촌)에 pH 1.8, 2.3, 2.8인 인공산성비와 PH 6.0인 인공비를 출아 또는 정식 후 30일 부터 수확기까지 2주 간격(감자는 1주 간격)으로 처리하여 얻은 결과는 다음과 같다. 1. 인공산성비에 의한 잎의 가시적 피해는 벼, 콩, 고추는 pH 1.8과 2.3처리에서는 갈색 반점으로 나타났고, pH가 낮을수록 피해가 더 심했다. 감자는 어느 pH의 인공산성비 처리에서도 가시적 피해가 없었다. 2. 엽록소 함량은 벼와 감자에서는 인공산성비 처리간에 차이가 없었지만 고추와 콩에서는 인공산성비 pH가 낮을수록 잎의 엽록소 함량이 감소하였다. 3. 광합성 능력은 벼에서는 인공산성비 pH간에 차이가 없었다. 그러나 콩, 감자, 고추는 pH 2.8과 6.0에서는 차이가 없었으나 pH 2.8이하에서는 pH가 낮을수록 광합성 능력이 감소하였다. 4. 벼, 콩, 감자의 수량은 인공산성비 pH간에 차이가 없었으나 고추에서는 인공산성비의 pH가 낮을수록 과장, 과경, 1 과중, 주당 과실수, 과실 수량은 감소하였다. 5. 산성비에 대한 내성이 큰 벼와 감자에서는 가시적 피해가 다른 조사형질과는 상관이 없었다. 한편 내성이 약한 콩과 고추에서 가시적 피해는 콩의 엽록소 함량과 광합성 능력, 고추의 광합성 능력과 수량간에 부의 상관이 있었다.

• 한국식품저장유통학회지
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• 제22권2호
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• pp.256-260
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• 2015

본 연구에서는 알칼리 사용에 따른 갈변을 최소화하고 영양적으로 우수한 천마 단백질을 보다 효율적으로 추출하기 위하여 용출 및 침전 pH에 따른 단백질의 갈변도와 함량을 측정함으로써 탈지 천마 단백질 알칼리 추출의 최적 pH 조건을 설정하고자 하였다. 천마의 수분은 약 15%로 측정되었으며, 대부분 탄수화물로 구성되어 있었고, 단백질의 함량이 높은 것으로 확인되었다. 이러한 단백질을 다양한 pH에서 용출시킨 결과 pH가 증가함에 따라 용출된 단백질의 양이 증가하였으며, 갈변도 또한 증가함을 보였다. 침전 pH에 따른 단백질 함량은 pH 4에서 침전된 pellet이 가장 많은 함량을 나타내었으며, 상등액의 단백질 함량 또한 대부분 pH 4로 침전시킨 경우 가장 적은 것으로 확인되었다. 뿐만 아니라 단백질의 회수율도 침전 pH가 4일 때 가장 높은 값을 나타내었다. 따라서 갈변도와 단백질 함량을 고려한 탈지 천마 단백질 추출을 위한 최적조건은 용출 pH 9와 침전 pH 4로 결정되었다.

• Advances in Energy Research
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• 제2권1호
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• pp.1-9
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• 2014

The green microalgae Chlamydomonas reinhardtti is well-known specie in the terms of $H_2$ production by photo fermentation and has been studying for a long time. Although the $H_2$ production yield is promising; there are some bottlenecks to enhance the yield and efficiency to focus on a well-designed, sustainable production and also scaling up for further studies. D1 protein of photosystem II (PSII) plays an important role in photosystem damage repair and related to $H_2$ production. Because Chlamydomonas is the model algae and the genetic basis is well-studied; metabolic engineering tools are intended to use for enhanced production. Mutations are focused on D1 protein which aims long-lasting hydrogen production by blocking the PSII repair system thus $O_2$ sensitive hydrogenases catalysis hydrogen production for a longer period of time under anaerobic and sulfur deprived conditions. Chlamydomonas CC124 as control strain and D1 mutant strains(D240, D239-40 and D240-41)are cultured photomixotrophically at $80{\mu}mol\;photons\;m^{-2}s^{-1}$, by two sides. Cells are grown in TAP medium as aerobic stage for culture growth; in logarithmic phase cells are transferred from aerobic to an anaerobic and sulfur deprived TAP- S medium and 12 mg/L initial chlorophyll content for $H_2$ production which is monitored by the water columns and later detected by Gas Chromatography. Total produced hydrogen was $82{\pm}10$, $180{\pm}20$, $196{\pm}20$, $290{\pm}30mL$ for CC124, D240, D239-40, D240-41, respectively. $H_2$ production rates for mutant strains was $1.3{\pm}0.5mL/L.h$ meanwhile CC124 showed 2-3 fold lower rate as $0.57{\pm}0.2mL/L.h$. Hydrogen production period was $5{\pm}2days$ for CC124 and mutants showed a longer production time for $9{\pm}2days$. It is seen from the results that $H_2$ productions for mutant strains have a significant effect in terms of productivity, yield and production time.

• Korean Chemical Engineering Research
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• 제51권1호
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• pp.111-115
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• 2013

Horseradish peroxidase 효소촉매를 이용하여 dioxane:수용액(80:20 v/v) 혼합용액에서 poly(p-phenylphenol) 수지를 합성하기 위한 최적 반응조건과 생성된 수지의 열분해 안정성과 가열특성을 thermogravimetric analysis (TGA)와 differential scanning calorimetry (DSC) 방법을 통해서 각각 조사하였다. 효소의 사용량이 0.25 mg/mL로 증가할 때 수지의 합성수율은 급격하게 증가하였으나 효소의 사용량이 0.25 mg/mL 이상으로 증가하더라도 수지의 합성수율은 크게 증가하지 않았다. 또한 sodium acetate (100 mM, pH 4~6)와 sodium phosphate (100 mM, pH 7~9) 완충용액을 수용액으로 사용할 경우 pH가 증가할수록 페놀수지의 합성수율이 증가하였다. 그러나 수용액의 pH가 6과 9일 때, 수지의 합성수율은 사용하는 완충염의 종류에 따라서 크게 좌우되었다. 즉 pH 6에서 sodium acetate 대신 sodium phosphate를 사용하면 합성 수율은 15% 정도 감소하였다. 또한 pH 9에서 sodium phosphate 대신 sodium bicarbonate를 사용할 경우 합성 수율이 약 20% 정도 크게 감소하였다. 수용액의 pH가 4~7 범위에서 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) (ABTS)를 전자전달체로 사용하면(2 mM) 합성 수율이 약 10% 정도 향상되었다. TGA 실험결과 pH 9인 수용액에서 ABTS가 2 mM이 첨가된 합성수지의 $800^{\circ}C$에서의 잔류량(char yield)이 47%로 열분해 안정성이 가장 우수하였다. DCS 측정 결과 산성수용액에서 합성된 수지와 중성 및 염기성 수용액에서 합성된 수지의 구조특성은 서로 달랐다. 그러나 모든 합성수지는 열경화성 수지의 특성을 보여주었다.

• Animal Bioscience
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• 제34권5호
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• pp.833-843
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• 2021

Objective: Current study was conducted to determine the effect of postpartum prostaglandin F2α (PGF2α) administration on colostrum and milk yield, colostrum immunoglobulin G (IgG) and piglet growth performance. Methods: In total, 36 sows were included in the experiment. The sows were classified into two groups: i) control (n = 11) and ii) PGF2α (n = 25). Sows in the PGF2α group received 10 mg of PGF2α within an hour after farrowing. The body weight of piglets was measured at 0 and 24 h after birth to estimate colostrum consumption. Colostrum was collected at 1 and 24 h after farrowing to determine IgG concentrations. For milk yield study, the remaining sows in the PGF2α group (n = 23) were divided into two subgroups: i) single PGF2α (n = 12) and ii) multiple PGF2α (n = 11). In the multiple PGF2α, the sows received repeated doses of PGF2α at seven and 14 days postpartum. The piglets' body weight was measured at 0, 1, 5, and 20 days of age. The milk yield of the sows was calculated. Results: Colostrum yield of sows averaged 5.62±2.25 kg. Sows treated with PGF2α postpartum had a higher colostrum yield than control (7.01 and 5.12 kg, p<0.05). The concentration of IgG in colostrum at 24 h in the PGF2α group was higher than the control (31.6 and 17.4 g/L, p<0.05). For primiparous sows, milk yield was highest in the sows treated with multiple doses of PGF2α during lactation and lowest in control sows (10.25 and 7.61 kg, p<0.05). Colostrum intake was higher in the treatment than the control groups (+56.7 g, p<0.05). Primiparous sows treated with multiple doses of PGF2α had a higher litter weight than controls (p<0.01). Conclusion: Postpartum treatment with PGF2α improved colostrum yield and IgG in multiparous sows and increased colostrum intake of piglets. Multiple administration of PGF2α improved the milk yield and increased litter weight of piglets in primiparous sows.

• 약학회지
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• 제30권1호
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• pp.31-41
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• 1986

Sarcolemmal membrane fraction from canine ventricle was isolated from the discarded pellet after the first homogenization in the isolation procedure of sarcoplasmic reticulum (Method 1) and the protein yield, purity, and sidedness of this preparation were compared to those of sarcolemmal fraction prepared by method of Lee et al. (Method 2) and a slight modification of original protocol of Jones et al. (Method 3). Method 1 differed from Method 2 essentially only in that vigorous homogenization was carried out by omnimixer and homogenization medium containing 30mM Tris-maleate was used in the first step. The sarcolemmal fraction was enriched from 45 to 50 and 29-fold in [$^3H$] ouabain, [$^3H$] DHA, [$^3H$] QNB binding and $Na^+$, $K^+$-ATPase activity, respectively, compared to homogenate. Total $Na^+$, $K^+$-ATPase activity of highly sarcolemma enriched fraction was 144.6$\pm$16.4$\mu\textrm{mol}$ Pi/mg protein/hr, which was about 85%, of total ATPase activity, and the yield of the preparation was 15.7 mg protein per 100g of starting ventricular tissue. The sarcolemmal preparation supported $^{45}Ca^{2+}$-uptake in the presence of ATP but this uptake was not dependent on oxalate. Sarcolemmal $Na^+$, $K^+$-ATPase activity and detectable [$^3H$] ouabain binding were increased about 32% and 35%, respectively, by pretreatment of sarcolemmal fraction with optimal concentration of sodium dodecylsulfate (0.3-0.4mg/mg protein), suggesting that this preparation contained about 24% of sealed rightside-out vesicles, 26% of sealed inside-out vesicles, and 5001o of freely permeable (leaky) form. This procedure showed the highest protein yield and leaky population, compared to Method 2 and 3. On the other hand, sarcolemmal fraction prepared by Method 2 and 3 showed low value in protein yield but comtained high population of inside-out (46%) and rightside-out (49%) vesicles, respectively, compared to present procedure (Method 1). The results indicate that vigorous homogenization decreases the population of sealed sarcolemmal vesicles but increases the sarcolemmal protein yield per gram tissue and that this procedure is available for further purification of sarcolemmal fraction and for the receptor binding study of sarcolemma.