• Fisheries and Aquatic Sciences
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• 제25권2호
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• pp.76-89
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• 2022

The Lophius litulon liver was used as raw material for the extraction of fish oil via various extraction methods. The extraction rate by water extraction, potassium hydroxide (KOH) hydrolysis and protease hydrolysis were compared and the results revealed the protease hydrolysis extraction had a higher extraction rate with good protein-lipid separation as observed by optical microscope. Furthermore, subsequent experiments determined neutrase to be the best hydrolytic enzyme in terms of extraction rate and cost. The extraction conditions of neutrase hydrolysis were optimized by single-factor experiment and response surface analysis, and the optimal extraction rate was 58.40 ± 0.25% with the following conditions: enzyme concentration 2,000 IU/g, extraction time 1.0 h, liquid-solid ratio 1.95:1, extraction temperature 40.5℃ and pH 6.5. The fatty acids composition in fish oil from optimized extraction condition was composed of 19.75% saturated fatty acids and 80.25% unsaturated fatty acids. The content of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were 8.06% and 1.19%, respectively, with the ratio (6.77:1) surpassed to the recommendation in current researches (5:1). The results in this study suggest protease treatment is an efficient method for high-quality fish oil extraction from Lophius litulon liver with a satisfactory ratio of DHA and EPA.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.593-596
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• 2000

Chiral epoxides are useful chiral synthons in organic synthesis and various biological methods have been investigated for the production of chiral epoxides. In this work, enantioselective resolution of racemic styrene oxide was investigated using an isolated Aspergillus niger sp. for the production of optically pure (S) -styrene oxide. The enantioselectivity and initial hydrolysis rates of racemic substrate were highly dependent on the pH, temperature, and the volume ratio of cosolvent. The experimental sets of pH, temperature, and the volume ratio of cosolvent were designed using central composite experimental design, and the reaction conditions were optimized using response surface analysis. The optimal conditions of pH, temperature, and the volume ration of cosolvent were determined to be 7.78, $28.32^{\circ}C$, and 2.4 %(v/v), respectively, and optically pure (S)-styrene oxide (> 99% ee) could be obtained with the 35 % yield by microbial enantioselective hydrolysis reaction.

• KSBB Journal
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• 제8권4호
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• pp.358-363
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• 1993

부산물이 거의 생기지 않는 반응조건에서 inulin의 산 가수분해 반응에 미치는 초음파의 영향을 조사했다. 반응조건은 50~$60^{\circ}C$와 염산 0.1~0.3%(w/w)의 상당히 완화된 범위였으며, 항온조 내 반응기 위치와 기계적인 교반에 대한 영향을 조사했다. 초음파를 사용한 경우와 하지 않은 경우 fructose생성속도를 온도와 산의 농도변화에 따라 비교했으며 두 경우 활성화에너지는 25kcal/mol로 같았다. 초음파에 의한 반응속도 증가는 평균 22%였다.

• KSBB Journal
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• 제29권3호
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• pp.193-198
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• 2014

Pretreatment of wastepaper using aqueous glycerol under high pressure was studied to enhance the enzymatic hydrolysis. The pretreatment was conducted over a wide range of conditions including temperatures of $150{\sim}170^{\circ}C$, sulfuric acid concentrations of 0.5~1.5%, and reaction times of 30~90 minutes. After the effect of glycerol concentration on the pretreatment performance was investigated, 70% glycerol was selected. As glycerol concentration was increased, higher digestibility was achieved due to higher lignin removal. The optimum condition was found to be around $160^{\circ}C$, 1%, and 60 minutes. At this condition, 60% and 35% of hemicellulose and lignin, respectively, were removed, while only 5% of cellulose was lost. The enzymatic digestibility was 76%, meaning that 73% of the glucan present in the initial substrate was recovered as glucose after enzymatic hydrolysis. Also, it was found that the temperature and acid concentration than the reaction time were more strongly related to the compositional removals and enzymatic digestibility.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권3호
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• pp.211-214
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• 2006

Immobilized Candida antarctica lipase was used to catalyze the separation of ketoprofen into its components by means of esterification followed by the enzymatic hydrolysis of the ester product. In this study, ketoprofen underwent esterification to ethanol in the presence of isooctane. When the reaction was complete, 58.3% of the ketoprofen had been transformed into an ester. The ketoprofen remaining in solution after the reaction was complete consisted primarily of its S-enantiomer (83.0%), while the 59.4% of the ketoprofen component of the ester consisted of its R-enantiomer. We then subjected the ester product to enzymatic hydrolysis in the presence of the same enzyme and produced a ketoprofen product rich in the R-enantiomer; 77% of this product consisted of the R-enantiomer when 50% of the ester had been hydrolyzed, and 90% of it consisted of the R-enantiomer when 30% of the ester had been hydrolyzed. By contrast, the R-enantiomer levels only reached approximately 42 and 65%, respectively, when 50 and 30% of the racemic ester was hydrolyzed under the same conditions.

• 한국축산식품학회지
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• 제40권2호
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• pp.172-182
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• 2020

In the present study, we determined the degree of hydrolysis (DH) of porcine blood plasma proteins, albumin, and globulin hydrolyzed by six proteases (alcalase, neutrase, flavourzyme, protamex, trypsin, and papain) for various reaction times. Moreover, antimicrobial activities of hydrolysates against five pathogenic microorganisms (Bacillus cereus, Staphylococcus aureus, Salmonella Typhimurium, Escherichia coli, and Shigella flexneri) were investigated. Alcalase, trypsin, and papain hydrolysates of the three porcine blood proteins showed higher DH values than hydrolysates produced by the other three proteases. DH of the three porcine blood proteins hydrolyzed by the six proteases failed to increase after 2 h of hydrolysis. In antimicrobial tests, hydrolysates (hydrolysis time of 2 h) showed antibacterial activity only against B. cereus. Albumin hydrolysates showed higher antimicrobial activity than globulin and plasma hydrolysates. Albumin hydrolysates obtained with flavourzyme, protamex, and trypsin showed higher antimicrobial activity than those obtained with the other three proteases.

• 대한기계학회논문집B
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• 제20권5호
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• pp.1671-1678
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• 1996

In external chemical vapor deposition processes including VAD and OVD the distribution of flame-synthesized silica particles is determined by heat and mass transfer limitations to particle formation. Combustion gas flow velocities are such that the particle diffusion time scale is longer than that of gas flow convection in the zone of particle formation. The consequence of these effects is that the particles formed tend to remain along straight smooth flow stream lines. Silica particles are formed due to oxidation and hydrolysis. In the hydrolysis, the particles are formed in diffuse bands and particle formation thus requires the diffusion of SiCl$\_$4/ toward CH$\_$4//O$\_$2/ combustion zone to react with H$\_$2/O diffusing away from these same zones on the torch face. The conversion kinetics of hydrolysis is fast compared to diffusion and the rate of conversion is thus diffusion-limited. In the language of combustion, the hydrolysis occurs as a Burke-Schumann process. In selected conditions, reaction zone shape and temperature distributions predicted by the Burke-Schumann analysis are introduced and compared with experimental data available. The calculated centerline temperatures inside the reaction zone agree well with the data, but the calculated values outside the reaction zone are a little higher than the data since the analysis does not consider diffusion in the axial direction and mixing of the combustion products with ambient air. The temperatures along the radial direction agree with the data near the centerline, but gradually diverge from the data as the distance is away from the centerline. This is caused by the convection in the radial direction, which is not considered in the analysis. Spatial distribution of silica particles are affected by convection and diffusion, resulting in a Gaussian form in the radial direction.

• 한국응용과학기술학회지
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• 제33권1호
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• pp.176-185
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• 2016

연산오계는 오래전부터 건강기능 증진 및 치료 효능이 높은 것으로 알려져 왔다. 최근 건강기능식품 소재로 기능성 펩타이드 효능이 알려짐에 따라, 연산오계 다리육으로부 올리고 펩타이드 최적 생산 공정 및 생성물 특성에 대하여 연구를 수행하였다. 최적 효소가수 분해 공정 표면반응 분석을 이용하여 수행하였다. 최적 공정 조건을 확립하기 위해서 온도 (40, 50, $60^{\circ}C$), pH (pH 6.0, 7.0, 8.0), 효소 (1, 2, 3%) 범위에서 수행을 하였다. 생성물에 대한 가수분해도, 유리아미노산, 분자량 분포를 분석하였다. 효소 가수분해 최적 온도는 $58^{\circ}C$, pH 7.5, 효소의 농도는 3% 이었다. 최적 조건에서 2 시간 효소 가수분해를 한 결과 75-80% 이었다. 유리 아미노산 총량은 168.131 mg/100 g 이었다. 분자량를 MALDI-TOF 으로 분석을 한 결과 90% 이상이 300-1,000 Da 분포를 보여주었다.

• 한국식품영양과학회지
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• 제36권8호
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• pp.1031-1037
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• 2007

홍삼 융합청국장을 다양한 식품소재로 활용하고자 가수 분해 조건에 따른 특성변화를 조사하였다. 그 결과 4종류의 protease에 따른 홍삼 융합청국장 가수분해물의 특성은 protease(KMF-G)가 가수분해도, 칼슘결합능, 총 페놀화합물 함량이 가장 높은 것으로 나타났으며, 혈전용해능과 ACE 저해활성 또한 87.10 unit, 67.17%로 가장 높게 나타났다. Protease(KMF－G) 농도에 따른 영향을 조사한 결과 0.02%에서 적합하였다. 홍삼 융합청국장의 가수분해시간에 따른 영향은 60분과 90분에서 가장 양호한 결과를 나타내었으나 유의적 차이가 나타나지 않았으며, 홍삼 융합청국장 가수분해물의 불쾌취와 쓴맛은 60분 이상에서 개선되었으므로 최적 가수분해시간은 60분으로 설정할 수 있었다. 홍삼 융합청국장의 총 진세노사이드 함량은 9.197 mg/g이고, 홍삼 융합청국장 가수분해물의 함량은 11.707 mg/g이었다. 이상의 결과 protease(KMF-G), 0.02%를 첨가하여 60분간 가수분해 하였을 때 이화학적 특성, 혈전용해능 및 ACE 저해활성이 향상된 홍삼 융합청국장 가수분해 조건을 설정할 수 있었다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.303-307
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• 2001

반응표면분석법을 이용하여 우지의 고온, 고압가수분해 공정조건을 최적화 시키고자 하였다. 이때 선정된 공정의 독립변수로는 반응온도, 반응압력 그리고 fat/water ratio이었으며 이에 대한 중속변수로는 TG, FFA, 1,3-DG, 2,3-DG 그리고 MG을 선정하였다. 반응압력을 이산화탄소를 이용하여 가수분해반응속도를 증가시키고자 하였지만 지방산 생성농도에는 커다란 영향을 미치지는 않았다. 지방산 생성농도에 대해서는 다른 공정변수들에 비해 반응온도에 크게 의존하였고, Derringer-Suich 방법을 이용한 지방산 생성농도를 최적화 시킬 수 있는 조건으로는 반응온도 $271^{\circ}C$ 반응압력 86 bar 그리고 far/water ratio 106.08g/133.92g를 얻었으며 이 조건에서 3시간동안 가수분해하여 얻은 FFA생성농도는 96.49%로 얻었다. 통계적 분석에 이용된 자료들은 유의성 검증, 적합결여, 그리고 잔차분석 등을 해석한 결과 모든 자료가 95%이상의 신뢰도를 가지므로 매우 유익한 것으로 사료된다.