• Food Science and Biotechnology
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• 제18권1호
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• pp.185-189
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• 2009

Microencapsulation of flavor was carried out by molecular inclusion process using $\beta$-cyclodextrin (${\beta}CD$). ${\beta}CD$-flavor complex was prepared at various flavor-to-${\beta}CD$ ratios (1:6-1:12) to determine the effect of ${\beta}CD$ concentration on the inclusion efficiency. Maximum total oil retention and minimal surface oil content were obtained at flavors to ${\beta}CD$ ratio of 1:10. The physical properties and controlled release pattern of flavors from ${\beta}CD$-flavor complex were measured and compared with spray-dried microcapsules prepared using carbohydrate wall system. ${\beta}CD$-flavor complex showed higher total oil retention and surface oil contents, smaller mean particle size, lower moisture uptake, and higher oxidation stability than spray-dried microcapsule. Oxidative stability of flavor was correlated with hygroscopicity of wall materials. The controlled release mechanism was highly affected by temperature and characteristics of wall materials.

• 약학회지
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• 제35권6호
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• pp.530-554
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• 1991

The synthetic methodologies for the preparation of C-nucleosides are divided into four categories, and each category is discussed in details. The chemical rections which lead to other C-nucleosides from preformed the natural product pseudouridine are described first, followed by synthesis of C-nucleosides by condensation of pre-formed heterocyclic base with sugar, and by construction of heterocyclic base from a carbohydrate intermediate that bear functional carbon fragment at the anomeric position. Finally, methods of total synthesis of C-nucleosides from carbohydrate and achiral starting materials are presented.

• 생물환경조절학회지
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• 제26권4호
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• pp.291-296
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• 2017

본 연구에서는 사과 '후지'/M9의 생육기간 중 조기낙엽 피해가 발생하였을 때 영향을 알아보기 위하여 인위적으로 적엽 처리하여 광합성과 탄수화물의 변화를 측정하였다. 눈의 재발아율은 대조구, 50% 처리구, 80% 처리구에서 각각 2.1%, 45.9%, 82.7%로 매우 유의한 차이를 나타냈다. 적엽처리 후 남은 잎의 자당(sucrose)와 전분 함량을 측정한 결과 모든 처리구에서 유의한 차이는 없었다. 또한 대조구와 50% 처리구에서는 총 유리당의 변화도 크지 않았다. 반면 80% 처리구에서 총 유리당과 sorbitol의 함량은 처리 후 14일동안 꾸준히 감소하였으며, 이것은 대조구에 비하여 높은 sink로서의 탄수화물요구가 일어난 것으로 추정된다. 뿌리에서의 전분 축적은 적엽처리 정도가 심할수록 감소하였으나 유의한 차이는 없었다. 광합성속도와 기공전도도는 80% 처리구에서 처리 후 14일동안 꾸준히 유의하게 증가하였다. 광합성 속도의 상승은 남아있는 source 잎에서의 삼투포텐셜이 증가하여 발생한 것으로 판단된다. 이는 적엽처리로 인하여 눈의 당년 2차 재발아에 필요한 sink의 탄수화물 요구가 갑작스럽게 일어나게 됨으로써 남아있는 잎에서 광합성이 증가한 것으로 추정된다.

• 한국수산과학회지
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• 제50권1호
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• pp.32-40
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• 2017

The aim of this study was to evaluate a temperature-induced two-stage cultivation (TTC) strategy for the regulation of lipid and carbohydrate production by two microalgae, Chlorella vulgaris and Dunaliella salina, for biofuel production. The microalgae were grown under several temperature conditions (15, 25, 35, and $45^{\circ}C$) and optimal growth was observed at $25^{\circ}C$ for both microalgae. To test the TTC, aseptically cultured microalgae were incubated under optimal conditions ($25^{\circ}C$) for 20 days, and then divided into four aliquots that were incubated at 15, 25, 35, and $45^{\circ}C$ for 5 days. Similar but somewhat decreased growth rates were observed at the non-optimal temperatures (15, 35, and $45^{\circ}C$). In addition, while total lipid accumulation increased in a temperature-dependent manner in both microalgae, total carbohydrate increased with temperature in C. vulgaris but decreased in D. salina. However, for lipid and carbohydrate production, while the highest lipid productions of C. vulgaris and D. salina were observed at $25^{\circ}C$ and $35^{\circ}C$, respectively, the highest total carbohydrate productions of C. vulgaris and D. salina were obtained at $15^{\circ}C$ and $25^{\circ}C$, respectively. These results suggest that the TTC strategy may be easily and efficiently applied to bioprocessing for biofuel production.

• Journal of Nutrition and Health
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• 제9권3호
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• pp.8-17
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• 1976

This study was carried out to estimate the minimum protein requirement for the Korean college girls, and to see the effect of carbohydrate intake on the minimum protein requirement in the rat. In the first experiment, three students attending Ewha Womans University were given protein free diet for 7 days while caloric intake were adjusted to maintain constant body weight. Endogenous nitrogen excretion was measured to estimate their minimum protein requirement. Second experiment was carried out in 3 parts to find out the effect of carbohydrate intake on the minimum protein requirement using 15 female, 50 days old rats weighing 120g. Inexperiment 2-1, the rats were fed protein free diet for 9 days and endogenous nitrogen excretion was measured to determine the minimum protein requirement of the rats. In experiment 2-2, the minimum casein requirement of the rats needed to maintain nitrogen equilibrium was estimated by the least squares regression method feeding 3 different levels of casein determined from the result of experiment 2-1. Finally, in experiment 2-3, the rats were given the minimum casein requirement for 7 days with 3 different levels of carbohydrate to find out the effect of carbohydrate intake on the nitrogen balance. The results of this study were as follows. Experiment I. Daily endogenous nitrogen losses of 3 college girls were 1.89g in urine, 1.10g in feces and 0.0108g from skin since the total daily endogenous nitrogen loss was 3.0g and the total daily nitrogen intake was 0.52g, the minimum nitrogen requirement of these subjects was about 2.48g/day (15.5g protein/day). Experiment II. Experiment 2-1: daily endogenous nitrogen losses of the rats fed protein free diet were $22.63{\pm}0.48\;mg$ through urine and $13.12{\pm}0.47\;mg$ in feces. The total daily endogenous nitrogen ouput was $35.71{\pm}1.27\;mg$ and the minimum protein requirement of the rats was 225mg/day in this study. Experiment 2-2: the minimum casein requirement needed to maintain the rats in nitrogen equilibrium was determined to be 340mg/day. Experiment 2-3: the rats were given 350mg/day casein with 3 different levels of carbohydrate (12,26 or 46 Cal by sugar-cornstarch mixture). The nitrogen balances were measured to be +0.0021, +0.0073 and +0.0143 respectively and there were significant differences among 3 groups.

• Animal Bioscience
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• 제36권2호
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• pp.256-263
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• 2023

Objective: Feed molecular structures can affect its availability to gastrointestinal enzymes which impact its digestibility and absorption. The molecular spectroscopy-attenuated total reflectance Fourier transform infrared vibrational spectroscopy (ATR-FTIR) is an advanced technique that measures the absorbance of chemical functional groups on the infrared region so that we can identify and quantify molecules and functional groups in a feed. The program aimed to reveal the association of intrinsic molecular structure with nutrient supply to animals from canola feedstocks and co-products from bio-oil processing. The objective of this study was to characterize special intrinsic carbohydrate and protein-related molecular structure spectral profiles of feedstock and co-products (meal and pellets) from bio-oil processing from two source origins: Canada (CA) and China (CH). Methods: The samples of feedstock and co-products were obtained from five different companies in each country arranged by the Canola Council of Canada (CCC). The molecular structure spectral features were analyzed using advanced vibrational molecular spectroscopy-ATR-FTIR. The spectral features that accessed included: i) protein-related spectral features (Amide I, Amide II, α-helix, β-sheet, and their spectral intensity ratios), ii) carbohydrate-related spectral features (TC1, TC2, TC3, TC4, CEC, STC1, STC2, STC3, STC4, TC, and their spectral intensity ratios). Results: The results showed that significant differences were observed on all vibrationally spectral features related to total carbohydrates, structural carbohydrates, and cellulosic compounds (p<0.05), except spectral features of TC2 and STC1 (p>0.05) of co-products, where CH meals presented higher peaks of these structures than CA. Similarly, it was for the carbohydrate-related molecular structure of canola seeds where the difference between CA and CH occurred except for STC3 height, CEC and STC areas (p>0.05). The protein-related molecular structures were similar for the canola seeds from both countries. However, CH meals presented higher peaks of amide I, α-helix, and β-sheet heights, α-helix:β-sheet ratio, total amide and amide I areas (p<0.05). Conclusion: The principal component analysis was able to explain over 90% of the variabilities in the carbohydrate and protein structures although it was not able to separate the samples from the two countries, indicating feedstock and coproducts interrelationship between CH and CA.

• 한국수산과학회지
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• 제41권5호
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• pp.337-342
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• 2008

Eight quality standards of the brown seaweed, Undaria pinnatifida were designed and evaluated with dry products collected from aquacultured and wild areas. Contents of n-3 fatty acids (stearidonic acid and eicosapentaenoic acid), anti-edema activity, and total carbohydrate were measured as functional criteria. Total bacteria and molds were counted for safety conditions. Amounts of a brown pigment fucoxanthin, debris, and moisture were measured to evaluate the visible status of the products. When the seaweeds were tested in 1 g dry weight basis, they showed n-3 fatty acids in the range of approximately 0.2-2.8 mg, total carbohydrate of 0.39-0.71 g, total bacteria of $10^{4-6}$ cells, mold of $10^2$ cells, fucoxanthin of 0.4-1.5 mg, and debris of 10-24 mg. Anti-edema activity was 0.03-0.47 AU at 40 mg/mL extract. Moisture content was 11.4-12.6%.

• Asian-Australasian Journal of Animal Sciences
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• 제33권4호
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• pp.556-567
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• 2020

Objective: To improve the utility of native grass resources as feed in China, we investigated the dynamics of protein and carbohydrate fractions among Inner Mongolian native grasses, during ensiling and the aerobic stage, using the Cornell Net Carbohydrate and Protein System. Methods: Silages were prepared without or with lactic acid bacteria (LAB) inoculant. We analyzed the protein and carbohydrate fractions and fermentation quality of silages at 0, 5, 15, 20, 30, and 60 d of ensiling, and the stability at 0.5, 2, 5, and 10 d during the aerobic stage. Results: Inner Mongolian native grass contained 10.8% crude protein (CP) and 3.6% water-soluble carbohydrates (WSC) on a dry matter basis. During ensiling, pH and CP and WSC content decreased (p<0.05), whereas lactic acid and ammonia nitrogen (N) content increased (p<0.05). Non-protein N (PA) content increased significantly, whereas rapidly degraded true protein (PB₁), intermediately degraded true protein (PB₂), total carbohydrate (CHO), sugars (CA), starch (CB₁), and degradable cell wall carbohydrate (CB₂) content decreased during ensiling (p<0.05). At 30 d of ensiling, control and LAB-treated silages were well preserved and had lower pH (<4.2) and ammonia-N content (<0.4 g/kg of fresh matter [FM]) and higher lactic acid content (>1.0% of FM). During the aerobic stage, CP, extract ether, WSC, lactic acid, acetic acid, PB₁, PB₂, true protein degraded slowly (PB₃), CHO, CA, CB₁, and CB₂ content decreased significantly in all silages, whereas pH, ammonia-N, PA, and bound true protein (PC) content increased significantly. Conclusion: Control and LAB-treated silages produced similar results in terms of fermentation quality, aerobic stability, and protein and carbohydrate fractions. Inner Mongolian native grass produced good silage, nutrients were preserved during ensiling and protein and carbohydrate losses largely occurred during the aerobic stage.

• Bulletin of the Korean Chemical Society
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• 제31권3호
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• pp.555-556
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• 2010

• Bulletin of the Korean Chemical Society
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• 제29권3호
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• pp.535-536
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• 2008