• 한국식품영양과학회지
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• 제17권3호
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• pp.242-248
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• 1988

Pepsin, ${\alpha}-chymotrypsin$, protease 및 papain을 이용하여 정어리육 단백질의 pepsin가수분해물로 부터 합성한 plastein과 유리 glutamic acid 및 leucine을 도입시킨 plastein의 일반성분, 수율, 아미노산조성 및 분자량을 측정하여 비교 검토한 결과 plastein의 단백질 함량은$82.0{\sim}88.2%$였으며 회분함량은 $2.7{\sim}7.6%$로 glu-papain plastein과 leu-papain plastein의 2.5% 및 1.9%보다 높았고, 지방함량은 $0.3{\sim}0.8%$범위였다. 수율은 protease plastein이 52.3%로 가장 높았고, papan plastein, pepsin plastein 및 ${\alpha}-chymotrypsin$ plastein은 각각 44.2%, 43.6%, 43.2%였으며, leu papain plastein과 glu-papain plastein은 각각 33.2% 및 29.0%였다. plastein종류에 따른 아미노산조성에는 큰 차이는 없었으며, leu-papain plastin과 glu-papain plastein의 leucine 및 glutamlc acid 함량은 각각 37.5% 및 39.3%였으나 대조구인 papain plastein에서는 이들의 함량이 7.1%, 14.4%에 불과하였다. 겔여과에 의한 가수분해물의 분자량은 1,800 및 285인 것이 주종을 이루었으나 이외에 분자량 3,600 및 830인 획분도 존재하였다. plasteln의 분자량은 ${\alpha}-chymotrypsin$ plastein이 26,000 및 9,100였으며 pepsin plastein은 23,000이 주증을 이루었고, 10,000 및 4,300도 존재하였고, protease plastein의 분자량은 18,000였다. leu-papain plastein과 glu-papain plastein은 각각 29,000 및 19,000 였으나 papain plastein 은 13,000로 가장 낮았다.

• 한국미생물·생명공학회지
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• 제18권5호
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• pp.517-524
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• 1990

CTAB/hexanol/isooctane 역미셀을 이용하여 단백질을 선택적으로 분리할 수 있는 분리조건을 밝히기 위해서 먼저 분자량과 등전점이 다른 여러 단백질의 용해와 회수에 미치는 pH, 이온의 종류 및 이온 강도, 계면활성제의 종류 등 system parameters에 대해 연구 검토하였다. pH에 따른 단백질의 용해는 등전점이 낮은 pepsin이 pH5-7 이상, 등전점이 높은 lisozyme이나 ribonuclease-a는 pH11-12 이상으로 단백질이 계면활성제의 (+)전하와 반대전하인 (-)를 띠는 등전점 이상의 pH역역에서 용해가 가능하였다.

• 한국수산과학회지
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• 제42권6호
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• pp.574-579
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• 2009

Acid- and pepsin-solubilized collagens were extracted from the skin of shark (Isurus oxyrinchus) and their physicochemical properties were characterized by amino acid analysis, SDS-PAGE, the composition of collagen types, solubility and denaturation temperature. Acid - and pepsin-solubilized collagens from shark skin had an imino acid of 188.8 and 186.2 residues/1,000 amino acids, respectively. SDS-PAGE showed two different${\alpha}$ chains ($\alpha1$ and $\alpha2$) and $\beta$-component. The component ratio of type I and V was 10:1, and the type III was not found. Solubility of acid-soluble collagen was low in the range of pH 6.0 to pH 11.0. On the other hand, pepsin-solubilized collagen showed a low solubility in the range of pH 7.0-9.0. Temperature for denaturation of acid- and pepsin-solubilized collagens were $25^{\circ}C$ and $27^{\circ}C$, respectively.

• 대한수의학회지
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• 제44권2호
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• pp.269-277
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• 2004

Trichinella spiralis is one of the important zoonotic parasites with a wide variety of vertebrates hosts in nature. The purpose of this study were to analyze ESP(Excretory-Secretory Protein) antigen, to evaluate ELISA for the serological diagnosis of Trichinosis, and to survey T. spiralis infection in finishing pigs using the pepsin digestion method and ELISA in Korea. In the analysis of ESP antigen by SDS-PAGE and Western blot, 4 major bands (70, 55, 52.6, and 49 kDa) were revealed from the ESP antigen. Predilection sites of T. spiralis were the diaphragm, the tongue, masseter muscles, intercostal muscle, and hindlimb in orders in the experimentally infected rats. Sera from 581 swine were tested by ELISA with ESP antigen. The 54 (9.3%) sera were suspected as positive reactors, however, these 54 sera were determined as false positives by the use of Western blotting. This study demonstrated that the ELISA was not suitable for the examination of T. spiralis in pork. The diaphragm muscle samples of 251 finishing pigs were tested by the method of pepsin-digestion for the presence of Trichinella larvae, however, T. spiralis was not detected from the samples. We could not find out T. spiralis infection in pig in Korea pork.

• Food Science and Biotechnology
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• 제18권3호
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• pp.706-711
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• 2009

Lysozyme was treated with digestive enzymes and the production of interleukin 8 (IL-8) was measured in Caco-2 cell with the peptides from lysozyme upon stimulating with lipopolysaccharide (LPS) to investigate the overall anti-inflammatory activity of lysozyme when it is in digestive tracts. Lysozyme reduced IL-8 production, and the peptides from pepsin hydrolysis of lysozyme had the similar effect. The products of trypsin digestion of lysozyme had no effect on the reduction of IL-8 production while those of pepsin-trypsin hydrolysis did. The effectiveness of lowering IL-8 production was not different by time of the peptide addition. When Caco-2 cells were pre-incubated with peptides for 24 hr, the reduction effects were observed from the peptides from pepsin hydrolysis, indicating that some of the peptides are still remaining in the cells. Therefore, it can be concluded that the IL-8 reduction effect of lysozyme against LPS still remained even after the pepsin and trypsin hydrolysis.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• 제8권5호
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• pp.433-441
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• 1995

A series of experiments was conducted to determine the influence of various pepsin-HCL pretreatment factor, hereby the factors of duration of washing for the retrieved bags, inherent to the mobile nylon bag technique (MNBT), on apparent ileal digestibility of crude protein (AIDCP) and apparent ileal digestibility of dry matter (AIDDM). At last, the AIDCP and apparent ileal digestibility of amino acids (AIDAA) in maize, barley, wheat, rapeseed meal, cottonseed meal and three mixed diets were determined with the MNBT and ileo-rectal anastomis pigs (IRAT). For the MNBT techniques, bag measuring $25{\times}40$ MM and containing 0.75 g feedstuff samples, after pre-digestion in vitro, were introduced into the ileo-rectal anastomis pigs (IRAT) gastrointestinal tract through a duodenal cannula and recovered in the ileal digesta between 6 and 12 h. later. 1. The apparent ileal digestibility of dry matter (AIDDM) and crude protein (AIDCP) of the tested samples, with the exception of fish meal, determined by MNBT were not affected by the different pepsin-HCL pretreatment times in vitro between 2.5 h. and 4 h. 2. There was no significant (p > 0.05) difference of the AIDCP and AIDDM of maize determined by the MNBT among different pepsin concentration (0.03%, 0.07% and 0.1 %) treatment in vitro. 3. The AIDCP determined with the MNBT was affected by the washed and unwashed recovered bags from the ileal digesta. 4. The AIDCP and AID amino acids (AIDAA) of maize, barley, wheat, rapeseed meal, soya-bean meal, cottonseed meal and three mixed diets from the MNBT, with a solution of 0.01N HCL (PH 2) and 0.1% of pepsin concentration, a pepsin-HCL pretreatment time in vitro or 4h. and a washing time of the recovered bag from the ileal digesta compared well with those from the IRAT. The linear regression analysis showed a significant correlation (p < 0.01) of AIDCP and AIDDA between the IRAT and MNBT.

• Fisheries and Aquatic Sciences
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• 제24권12호
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• pp.406-414
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• 2021

The objective of this study was to investigate the yield and characteristics of collagen protein extracted from the muscle of four different species of mantis shrimp: Miyakella nepa, Harpiosquilla harpax, Erugosquilla woodmasoni, and Odontodactylus cultrifer. Mantis shrimp muscle was extracted by using a pepsin-solubilization technique, with 0.5 M acetic acid and 5% pepsin enzyme. The highest collagen yield was from M. nepa muscle (0.478 ± 0.06%), which was significantly greater (p < 0.05) than that from H. harpax, O. cultrifer, and E. woodmasoni (0.313 ± 0.03%, 0.123 ± 0.02%, and 0.015 ± 0.00%, respectively). The freeze-dried collagen appeared as thin fibers, and formed an opaque film. The pepsin-soluble collagen (PSC) from four mantis shrimp species was analyzed by gel electrophoresis. The results showed that all species of mantis shrimp contained type I collagen, consisting of β, α1, and α2 subunits with average molecular weights of 250, 145, and 118 kDa, respectively. The study of the solubility of collagen showed that, for NaCl, collagen had the highest relative solubility in 2% NaCl (80.20 ± 4.95%). In contrast, the solubility decreased at higher NaCl concentrations. However, in terms of pH, collagen had the highest relative solubility at pH 3 (91.32 ± 5.14%), and its solubility decreased at higher pH. FT-IR spectroscopy was used to compare the collagen with a model compound. Five wavenumbers in the spectrum for model collagen were identified: Amide A (3,406-3,421 cm^-1), amide B (2,916-2,940 cm^-1), amide I (1,639-1,640 cm^-1), amide II (1,539-1,570 cm^-1), and amide III (1,234-1,250 cm^-1).

• Food Science and Biotechnology
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• 제15권2호
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• pp.173-176
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• 2006

The effect of enzymatically hydrolyzed vital wheat gluten (EHG) on dough mixing and the baking quality of wheat flour frozen dough was examined. Three different proteases, pepsin, trypsin, and chymotrypsin, were tested individually, sequentially paired, or in combination of all three enzymes. Addition of 1% EHG produced no observable effect on the mixing properties of wheat flour dough. However, addition of 2.5% pepsin-hydrolyzed gluten decreased the mixing tolerance of the wheat flour, and 1% trypsin-hydrolyzed gluten increased the loaf volume of both frozen and non-frozen dough. This finding suggests that trypsin-hydrolyzed vital wheat gluten may serve as a baking additive in replacement for $KBrO_3$ to improve frozen dough quality.

• 동아시아식생활학회지
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• 제19권1호
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• pp.45-51
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• 2009

In this study, food protein hydrolysates were prepared from six types of food protein: purified meat protein, whole egg protein, casein, isolated soy protein, concentrated rice protein, and gluten. Food proteins were hydrolyzed with pepsin and ethanol (80%)-soluble fractions of pepsin hydrolysates were employed for analysis. The products were colorless and odorless powders with low fat content and good solubility. The MW (molecular weight) of the protein hydrolysates was confirmed to be $200{\sim}1,800$ via gel filtration. Free amino acid contents accounted for less than 5% of the samples. The results of our amino acid analysis revealed that all food protein hydrolysates preserved their original amino acid compositions and nutritional values of their source proteins with highly pure oligopeptide mixtures. These results show that the food protein hydrolysates prepared in these investigations should prove excellent dietary nitrogen sources for a variety of applications.