• Journal of Microbiology and Biotechnology
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• 제26권9호
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• pp.1557-1565
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• 2016

Itaconic acid (IA) is a dicarboxylic acid included in the US Department of Energy's (DOE) 2004 list of the most promising chemical platforms derived from sugars. IA is produced industrially using liquid-state fermentation (LSF) by Aspergillus terreus with glucose as the carbon source. To utilize IA production in renewable resource-based biorefinery, the present study investigated the use of lignocellulosic biomass as a carbon source for LSF. We also investigated the production of fumaric acid (FA), which is also on the DOE's list. FA is a primary metabolite, whereas IA is a secondary metabolite and requires the enzyme cis-aconitate decarboxylase for its production. Two lignocellulosic biomasses (wheat bran and corn cobs) were tested for fungal fermentation. Liquid hydrolysates obtained after acid or enzymatic treatment were used in LSF. We show that each treatment resulted in different concentrations of sugars, metals, or inhibitors. Furthermore, different acid yields (IA and FA) were obtained depending on which of the four Aspergillus strains tested were employed. The maximum FA yield was obtained when A. terreus was used for LSF of corn cob hydrolysate (1.9% total glucose); whereas an IA yield of 0.14% was obtained by LSF of corn cob hydrolysates by A. oryzae.

• Applied Biological Chemistry
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• 제41권1호
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• pp.73-77
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• 1998

두유박의 단백질 소재화를 위하여 셀룰레이즈(cellulase), 단백질 분해효소, 코지(koji), 효모 등의 복합처리에 의한 가용화 방법이 고형분 및 단백질 회수율, 아미노산, 유기산 조성에 미치는 영향을 고찰하였다. 셀룰레이즈와 단백질 분해효소를 복합 사용하여 두유박을 가수분해하는 것이 높은 고형분 회수율(80.2%) 및 단백질회수율(83.5%)을 얻을 수 있었고, 코지와 효모로 처리할 경우 유기산의 함량을 증대시킬 수 있었으며 양조간장 특유의 맛과 향을 내는데 효과적이었다. 특히 셀룰레이즈로 처리한 가수분해물에서 유기산 함량이 높았다. 유리 아미노산 함량은 코지보다 단백질 분해효소로 분해한 경우에서 높았으며 셀룰레이즈 처리는 유리 아미노산 함량에 큰 영향을 미치지 않았다. 두유박 가수분해물에 대한 관능검사 결과 코지로 가수분해한 시료가 관능적으로 우수하였으나 전체적인 기호도는 대조구로 사용된 양조간장에 비해 낮았다.

• 공업화학
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• 제23권2호
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• pp.164-168
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• 2012

본 연구는 갈조류인 다시마의 당 성분 함량에 대한 분석과 효소 및 유기산 가수분해물을 이용한 생물학적 바이오 에탄올 생산에 대해 연구하였다. HPLC를 이용한 당 성분 분석 결과 alginate가 total sugar의 65.99%로 가장 많은 것으로 확인되었으며, laminaran과 mannitol이 각각 6.24, 27.77%로 나타났다. 1.5% acetic acid를 이용하여 $121^{\circ}C$, 60 min 동안 가수분해 결과 최대 1.874 g/L의 환원당이 생성되었으며, ascorbic acid의 경우 2.0%에서 최대 4.291 g/L의 환원당이 생성되는 것으로 나타났다. Alginate lyase와 laminarinase와 같은 효소를 이용한 가수분해에서 환원당 생성량은 최대 2.219 g/L였다. 다시마 가수분해물을 이용한 에탄올 발효 결과 유기산을 처리했을 때에는 에탄올 생산량이 오히려 감소하는 것으로 나타났으며, alginate lyase와 laminarinase를 혼합처리 했을 때 에탄올 생산량이 1.26 g/L로 가장 높았다.

• 한국환경과학회지
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• 제16권10호
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• pp.1203-1208
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• 2007

Feathers are produced in huge quantities as a waste product at commercial poultry processing plants. Since feathers are almost pure keratin protein, feather wastes represent an alternative to more expensive dietary ingredients for animal feedstuffs. Generally they become feather meal used as animal feed after undergoing physical and chemical treatments. These processes require significant energy and also cause environmental pollutions. Therefore, biodegradation of feather by microorganisms represents an alternative method to prevent environment contamination. The aim of this study was to investigate cultural conditions affecting keratinolytic protease production by Bacillus pumilus RS7. We also assessed the nutritive value of microbial and alkaline feather hydrolysates, The composition of optimal medium for the keratinolytic protease was fructose 0.05%, yeast extract 0.3%, NaCl 0.05%, K2HPO4 0.03%, KH2PO4 0.04% and MgCl2 6H2O 0.01%, respectively. The optimal temperature and initial pH was $30^{\circ}C$ and 9.0, respectively. The keratinolytic protease production under optimal condition reached a maximum after 18 h of cultivation. Total amino acid content of feather hydrolysates treated by NaOH and B. pumilius RS7 was $113.8\;{\mu}g/ml$ and $504.9\;{\mu}g/ml$, respectively. Essential amino acid content of feather hydrolysates treated by NaOH and B. pumilius RS7 was $47.2\;{\mu}g/ml$ and $334.0\;{\mu}g/ml$, respectively. Thus, feather hydrolysates have the potential for utilization as an ingredient in animal feed.

• 한국잠사곤충학회지
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• 제37권2호
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• pp.142-153
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• 1995

특이한 분자 구조를 가진 생체 고분자로서 유용한 견 피브로인은 다양하게 성형 가공할 수 있으며 이를 위해서는 견 피브로인 수용액을 필요로 한다. 견 피브로인의 용해 조건이 형성되는 견 피브로인의 분말과 필름에 미치는 영향을 알아보기 위하여 종성염과 산가수분해법으로 견 피브로인을 용해시킨 수용액으로부터 견 피브로인 분말과 필름을 제조하고 이들의 특성을 아미노산 조정 분석, SEM, DSC, IR, X-ray Diffraction 등의 방법을 통하여 조사 분석한 결과는 다음과 같다. 1. 염화칼슘법과 염산법에 의해 피브로이을 용해시켰을 때 처리에 따라 아미노산 조성은 달랐으며 분자량도 차이가 있었다. 2. 분말의 구조 분석 결과, 염화칼슘법에 의한 처리에서 열분해 온도는 대조에 비해 낮게 나타났고 무정형의 분자 구조를 띄고 있음을 알 수 있었다. 염산 처리에 의한 잔유물은 대조보다 높은 온도에서 $\beta$구조에 의한 분해 거동을 보였으며 높은 결정화도를 나타냈다. 한편 염산에 용해된 부분은 열분해 분석 결과 a-helix에 의한 흡열 peak을 나타냈다. 3. 염화칼슘법에 의해 형성된 견 피브로인 필름은 모정형에 가까운 결정 구조를 가지고 있지만 불용화 처리에 의해 결정성이 향상됨에 따라 피브로인 필름의 흡습율은 감소하였으며, 열분해 온도가 증가했다.

• 한국식품영양과학회지
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• 제22권2호
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• pp.215-221
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• 1993

간장을 속성으로 제조할 목적으로 간장국을 고온(40, 45, 5$0^{\circ}C$) 으로 속성분해 하는 조건을 검토하였다. 국의 고온분해시 4$0^{\circ}C$에서 식염 농도가 15%이상, 45$^{\circ}C$에서는 12%이상, 5$0^{\circ}C$에서는 8%이상에서 국 분해액이 안전하였다. 총질소의 용출은 5$0^{\circ}C$, 식염농도가 9%일 때 1.75%로 가장 높은 수치를 나타내었다. 환원당은 45$^{\circ}C$에서 식염농도가 12%일 때 7.2%이였고, formol질소는 45$^{\circ}C$에서 식염농도가 12%일 때 0.9%이었다. 점도는 45$^{\circ}C$에서 식염농도가 15%일때 12일 경과시 점도가 제일 양호하였다. 한편 국 분해액에서 추출된 유리 아미노산은 45$^{\circ}C$일 때 3268mg%로서 가장 높았다. 유리 아미노산 중 glutamic acid, leucine, arginine, aspartic acid, lysine, valine 및 phenylalanine이 전체 아미노산의 절반 이상을 차지 하였다.

• KSBB Journal
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• 제26권4호
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• pp.317-322
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• 2011

Ulva pertusa is one of the worst pollutant like a waste vinyl after agriculture and caused bad smell at seashore in Jejudo and south area of korean peninsular. For favorable environmental utilization of Ulva pertusa, it could be applied for ethanol production with its acid hydrolysate. The components of hydrolysate included fermentable sugar of glucose, xylose, mannose, galactose, and higher amounts of unfermentable rhamnose. Fermentable sugars were converted to ethanol with S. cerevisiae, also xylose to ethanol with P. stipitis, their maximun ethanol production at optimum conditions were 462 ${\mu}g$/mL and 475 ${\mu}g$/mL, respectively. While, rhamnose cannot be changed to ethanol with S. cerevisiae or P. stipitis, alone. Combination of S. cerevisiae and P. stipitis can convert rhamnose to ethanol, because P.stipitis degradaded rhamnose to pyruvate, and then S. cerevisiae convert to ethanol, at optimum conditions, ethanol reached to 782 ${\mu}g$/mL (30.24%) that is higher than that of 2 strain alone from 500 mg of dried Ulva pertusa contained 2586.45 ${\mu}g$/mL of reduced sugars. Ulva pertusa can be utilized for renewal energy insted of environmenatal enemy.

• 한국축산식품학회지
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• 제34권1호
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• pp.14-19
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• 2014

This study investigated the effects of protease treatments (trypsin, chymotrypsin, and pepsin) under various pressure levels (0.1-300 MPa) for the characteristics of porcine placenta hydrolysates. According to gel electrophoretic patterns, the trypsin showed the best placental hydrolyzing activity followed by chymotrypsin, regardless of the pressure levels. In particular, the peptide bands of tryptic-digested hydrolysate were not shown regardless of applied pressure levels. The peptide bands of hydrolysate treated chymotrypsin showed gradual decreases in molecular weights ($M_w$) with increasing pressure levels. However, the pepsin did not show any evidences of placental hydrolysis even though the pressure levels were increased to 300 MPa. The gel permeation chromatography (GPC) profiles showed that the trypsin and pepsin had better placental hydrolyzing activities under high pressure (particularly at 200 MPa), with lower $M_w$ distributions of the hydrolysates. Pepsin also tend to lower the $M_w$ of peptides, while the major bands of hydrolysates being treated at 300 MPa were observed at more than 7,000 Da. There were some differences in amino acid compositions of the hydrolysates, nevertheless, the peptides were mainly composed of glycine (Gly), alanine (Ala), hydroxyproline (Hyp) and proline (Pro). Consequently, the results indicate that high pressure could enhance the placental hydrolyzing activities of the selected proteases and the optimum pressure levels at which the maximum protease activity is around 200 MPa.

• Biomolecules & Therapeutics
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• 제26권3호
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• pp.268-273
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• 2018

Sleep is the most basic and essential physiological requirement for mental health, and sleep disorders pose potential risks of metabolic and neurodegenerative diseases. Tryptic hydrolysate of ${\alpha}_{S1}$-casein (${\alpha}_{S1}-CH$) has been shown to possess stress relieving and sleep promoting effects. However, the differential effects of ${\alpha}_{S1}-CH$ on electroencephalographic wave patterns and its effects on the protein levels of ${\gamma}$-aminobutyric acid A ($GABA_A$) receptor subtypes in hypothalamic neurons are not well understood. We found ${\alpha}_{S1}-CH$ (120, 240 mg/kg) increased sleep duration in mice and reduced sleep-wake cycle numbers in rats. While ${\alpha}_{S1}-CH$ (300 mg/kg) increased total sleeping time in rats, it significantly decreased wakefulness. In addition, electroencephalographic theta (${\theta}$) power densities were increased whereas alpha (${\alpha}$) power densities were decreased by ${\alpha}_{S1}-CH$ (300 mg/kg) during sleep-wake cycles. Furthermore, protein expressions of $GABA_A$ receptor ${\beta}_1$ subtypes were elevated in rat hypothalamus by ${\alpha}_{S1}-CH$. These results suggest ${\alpha}_{S1}-CH$, through $GABA_A$ receptor modulation, might be useful for treating sleep disorders.

• 한국축산식품학회지
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• 제35권3호
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• pp.360-369
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• 2015

Milk proteins have many potential sequences within their primary structure, each with a specific biological activity. In this study, we compared and investigated the bioactivities of hydrolysates of the domestic (A, B) and imported (C, D) skim milk powders generated using papain digestion. MALDI-TOF analysis revealed that all milk powder proteins were intact, indicating no autolysis. Electrophoretic analysis of hydrolysates showed papain treatment caused degradation of milk proteins into peptides of various size. The antioxidant activity of the hydrolysates, determined using 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and total phenolic contents (TPC) assays, increased with incubation times. In all skim milk powders, the antioxidant activities of hydrolysates were highest following 24 h papain treatment (TPC: A, 196.48 μM GE/L; B, 194.52 μM GE/L; C, 194.76 μM GE/L; D, 163.75 μM GE/L; ABTS: A, 75%; B, 72%; C, 72%; D, 57%). The number of peptide derived from skim milk powders, as determined by LC-MS/MS, was 308 for A, 283 for B, 208 for C, and 135 for D. Hydrolysate A had the highest antioxidant activity and the most potential antioxidant peptides amongst the four skim milk powder hydrolysates. A total of 4 β-lactoglobulin, 4 α_s1-casein, and 56 β-casein peptide fragments were identified as potential antioxidant peptides in hydrolysate A by LC-MS/MS. These results suggest that domestic skim milk could have applications in various industries, i.e., in the development of functional foods.