• Korean Journal of Bronchoesophagology
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• v.1 no.1
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• pp.55-63
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• 1995

Gastroesophageal reflux is thought to be an important etiology of the various upper aerodigestive tract disease. To investigate the role of gastric acid and pepsin as an etiologic factor of laryngotracheal stenosis, and the difference of injury by synthetic gastric juice between in ciliated respiratory epithelium and in squamous epithelium, experimental study was carried out using rabbits. Mucociliary transport affected by synthetic gastric juice was also studied in dogs. Synthetic gastric juice of low pH caused serious damage and Impairment of mucociliary transport in the epithelium of the larynx and trachea. Gastric acid played major role in the mucosal damage. Squamous epithelium of vocal folds and pharynx was more resistant to synthetic gastric juice than respiratory epitheium. In conclusion, gastroesophageal reflux may be an etiologic factor in the developement of laryngotracheal stenosis, so the adequate management is necessory In patients of laryngotracheal stenosis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.4 no.1
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• pp.49-53
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• 1975

The effect of natural condiments on peptic hydrolysis of casein in vitro has been studied, peptic activity was determined by the colorimetric method using folin reagent. The obstructive compounds on colorimetry from hydrolyzates of casein were separated by gel filteration method using sephadex G-10 column and 0.05M NaCl. Zinger and red pepper $(0.1{\sim}1.0%)$ were found to have slightly supressing effect for protein digestive action of pepsin. But garlic, green onion and onion acted as synergist for protein digertive action of pepsin.

• Journal of Aquaculture
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• v.16 no.4
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• pp.233-239
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• 2003

Growth and activities of digestive enzymes in slime flounder (Microstomus achne) larvae were measured from hatching to near the end of larval development (day 58). Larvae reared under starved and fed conditions and the changes of acid phosphatase (ACPase) specific activity, alkaline phosphatase (ALPase) specific activity, trypsin-like enzyme activity and pepsin-like enzyme activity were described with growth and developmental stage of larvae. Total length of the starved larvae was gradually increased for 7 days post hatching and then almost unchanged. Total length of the fed larvae ranged from 5.13$\pm$0.178 mm at the day of hatching to 13.43$\pm$1.395 mm at 58 days after hatching. In starved group, dry body weight decreased from 0.l0$\pm$0.020 mg at the day of hatching to 0.05$\pm$0.012 mg at 12 days after hatching. Dry body weight of fed larvae decreased during the prelarva stage like starved group and then gradually increased. ACPase and ALPase specific activity in the starved larvae increased until all larvae died, however those activities in the fed larvae increased until 20 days and then decreased until 58 days after hatching, with no significant difference between groups. Trypsin-like enzyme activity in the starved larvae was unchanged until 3 days and then was the highest on 5 days after hatching, but not detected after completion of yolksac absorption. Those of fed larvae decreased until 3 days and sharply increased until completion of yolksac absorption. The highest trypsin-like enzyme activity in the fed group was observed at 20 days after hatching. Trypsin-like enzyme activity in the fed larvae was significantly higher than that in the starved larvae from 8 days after hatching. Pepsin-like enzyme activity was increased in 5 days after hatching in both groups. There was significant difference at 8 and 10 days after hatching between both groups. Based on above results, digestive enzyme activities were correspondingly changed to a growth and morphological transformation. Trypsin-like enzyme and pepsin-like enzyme activities are able to be a useful indices for health and growth status in larval slime flounder, because there was significant difference in digestive enzyme activities with developmental stages, growth or feed supply.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.379-387
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• 2003

The freeze dried young antler was extracted by water and proteases. In case of water extraction, the extraction rate was highest when it was reacted in 5% of concentration for 6 hours at 50$^{\circ}C$. The result of HPLC analysis of extract shows that high molecular peak in water extract was transformed into low molecular polk by proteases. The rate of low molecular peak was highest when bacteria protease was used, and its second highest rate was pepsin, but the effect of papain on it was low, The extraction rate of young antler reacted for 5 hours was 33.4%(absorbance 13.25 at 280nm) of bacteria protease, 22.4%(absorbance 10.06) of papain, and 30.2% (absorbance 11.34) of pepsin. The young antler was boiled for 30min and it was reacted by proteases for 5 hours at 50$^{\circ}C$. The extraction rate of it was 47,6%(absorbance 12,54) of bacteria protease, and 26,4%(absorbance 7,48) of papain, and 45.6%(absorbance 7.23) of pepsin, In protein content, water extract was 52,1%, bacteria protease extract was 37.8%, and in amino acid content, water extract was 16.3%, bacteria protease extract was 31.96%, in ash content, water extract was 8.8%, bacteria protease extract was 5.6% by dry base. In mineral content, water extract contains 3.6% of Ca, 8.6% of P, 0.01% of Mg, 1.4 % of Na, 0.02 % of F, and bacteria protease extract contains 2.5% of Ca, 11.8% of P, 0.046 % of Mg, 2.1 % of Na, 0.018 % of F by dry base.

• Journal of Aquaculture
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• v.19 no.2
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• pp.125-132
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• 2006

Black rockfish larvae and juveniles were reared for 95 days after parturition (DAP) in order to determine four enzyme activities (trypsin, pepsine-like enzyme, lipase, amylase) during ontogeny. Larvae were fed rotifers Brachionus plicatilis from 1 to 25 DAP, Artemia nauplii from 10 to 78 DAP and then gradually changed to pelleted feed from 30 DAP. Temperature was kept between $13.5{\sim}14.9^{\circ}C$. Trypsin and lipase activities were found in 2 DAP larvae ($7.0{\pm}1.5$ unit and $4.5{\pm}1.4$ unit, $mean{\pm}SD$, respectively). The evolution of both enzymes activities showed a profile marked by drastic increases between postflexion and juvenile stage. There is an increment on specific trypsin activity at 10 DAP, corresponding with the beginning of Artemia feeding. Pepsin-like enzyme activity was found at 11 DAP and increased drastically from 56 DAP, cor-responding with the initiation of juvenile stage. Amylase activity was also found at 11 DAP and maintained at a low level up to 38 DAP followed by a drastic increase from 39 DAP to 50 DAP. Considering our results of both trypsin and pepsin-like enzyme activities, it might be concluded that higher somatic growth of Sebastes inermis could be possible with the initiation juvenile of stage and the early juvenile stage is a suit-able period for feeding an artificial diet for fish.

• Journal of Animal Science and Technology
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• v.44 no.6
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• pp.801-808
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• 2002

Proteolytic activities of some commercial milk clotting enzymes(rennet, trypsin, pepsin, papain W-40, neutrase 1.5 and protease S) in bovine skim milk containing 0.02% $CaCl_2$ were determined by measuring DH(Degree of Hydrolysis), NPN(Non Protein Nitrogen) and by comparing patterns of SDS-PAGE(Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis). The DH of microbial enzymes(neutrase 1.5 and protease S) and trypsin in bovine skim milk were higher than those of pepsin and papain W-40. The amounts of NPN in the milk treated with trypsin and the other animal enzymes(rennet and pepsin) showed the highest and lowest degrees of proteolysis, respectively. SDS-PAGE showed that trypsin and protease S hydrolyzed $\alpha$-lactalbumin and papain W-40 hydrolyzed $\beta$-lactoglobulin slightly, while neutrase 1.5 hydrolyzed both $\alpha$-lactalbumin and $\beta$-lactoglobulin after treating for 90 min. Trypsin and protease S easily hydrolyzed ${\alpha}_s$-casein and $\beta$-casein, which were not hydrolyzed by rennet. Papain W-40 hydrolyzed $\kappa$-casein more than rennet as shown in SDS-PAGE. Based on the results of the experiments, the DH and NPN of trypsin, neutrase 1.5 and protease S were shown to be higher than those of the other enzymes. The SDS-PAGE patterns of papain W-40 and neutrase 1.5 were similar with that of rennet.

• Journal of Animal Science and Technology
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• v.47 no.5
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• pp.851-856
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• 2005

The aim of this experiment was to evaluate the stability of anti-Helicobacter pylori IgY in water soluble fraction(WSF) of egg yolk according to the heat, pH and digestive enzyme treatment. Anti-H. pylori IgY content of WSF remained 76% after pasteurization(63$^{\circ}C$ for 30 min). The stability of anti-H. pylori IgY at different pH showed a tendency to diminish according to decreasing pH from 7.0 to 1.5(p＜0.05). Anti-H. pylori IgY content was 84.4% after treatment for 1 hour at 37$^{\circ}C$ in pH 5.0. There were significantly differences in IgY content between 1 hour and 2 hours at pH 2.0 in 200 units of pepsin treatment(p＜0.05). However, IgY was relatively stable at pH 4.0 regardless of the reaction time and the concentration of pepsin. The stability of IgY of egg yolk after the treatment of trypsin was significantly higher than that of water soluble fraction (p＜0.05). This results indicated that anti-H. pylori IgY showed relatively a good stability on heat, pH and digestive enzyme.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.540-546
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• 1999

The purpose of this study was to investigate the antimicrobial effects and characteristics of protamine extracted from spermary of tuna. The result of amino acids analysis showed that the contents of arginine were 46%. It was 10% lower when compared to standard protamine (SP: Asama kasei LTD, Japan). Also, there were significant difference in the contents of proline adn glycine. The average molecular weights of main protein in TP were 13,400 Da, whereas those in SP were 11,300 Da and 2,600 Da. To increase antimicrobial activities of TP, pepsin or trypsin was treated at $37^{\circ}C$. After TP was hydrolyzed with pepsin (pepsin hydrolyzed protamine: PHP) for 4hrs, the average molecular weights of the main protein were 11,300 Da and 3,900 Da, and the antimicrobial activities were significantly increased compared to TP. After TP was hydrolyzed with trypsin (trypsin hydrolyzed protamine: THP) for more than 10 min, the average molecular weights of the main protein were below 2,500 Da. PHP had higher antimicrobial effects on some gram positive bacteria (Staphylococcus aureus, Lactobacillus helveticus, Lactobacillus plantarum) than SP. However, THP had no antimicrobial activities. When TP was hydrolyzed with pepsin (PHP), its antimicrobial activities increased in the same level with those of SP, and this increase might be resulted rather from the changes of molecular weights of the main protein than from the contents of arginine in protamine.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.279-286
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• 2008

The antioxidative activity of various enzymatic extracts from leaves of Perilla frutescens var. japonica was evaluated by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl, and alkyl radical scavenging activity using an electron spin resonance (ESR) spectrometer. For this study, the leaves were enzymatically hydrolyzed by 8 carbohydrases (Dextrozyme, AMG, Promozyme, Maltogenase, Termamyl, Viscozyme, Celluclast, and BAN) and 9 proteases [Flavourzyme, Neutrase, Protamex, Alcalase, PP-trypsin (trypsin from porcine pancreas), papain, pepsin, $\alpha$-chymotrypsin, and BP-trypsin (trypsin from bovine pancreas)]. The DPPH radical scavenging activities of Promozyme and Alcalase extracts were the highest, and the $IC_{50}$ values were 77.25 and $109.66\;{\mu}g/mL$, respectively. All enzymatic extracts of the leaves scavenged hydroxyl radical, and the $IC_{50}$ values of Celluclast and pepsin extracts which were the highest activity were 243.34 and $241.86\;{\mu}g/mL$, respectively. The BAN and $\alpha$-chymotrypsin extracts showed the highest scavenging activities, and the $IC_{50}$ values were 21.13 and $33.23\;{\mu}g/mL$, respectively. The pepsin extracts from the leaves showed protective effect on $H_2O_2$-induced DNA damage. In addition, the pepsin extracts decreased cell death in PC-12 cells against $H_2O_2$-induced oxidative damage. The findings of the present study suggest that enzymatic extracts of the leaves possess antioxidative activity.

• Journal of Nutrition and Health
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• v.10 no.2
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• pp.27-34
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• 1977

The present study was carried out to evaluate the nutritional quality of rabbit meat protein. The composition of amino acids contained in rabbit meat was compared with those of other animal meats such as beef, pork and chicken. Also included in this study was the question whether the cooking and storage conditions affect the amino acid composition and the pepsindigestibility of rabbit meat protein. The results are summarized as follows: 1. The large variation observed from sample to sample of EAA (essential amino acid) composition in rabbit meat was found to be an interesting but peculiar property of rabbit meat protein. The most limiting amino acid of rabbit meat protein was phenylalanine, whereas methionine was the first limiting amino acid of both beef and pork proteins. Chemical scores of various meat proteins were 68, 65, 66, and 74 for rabbit meat, beef, pork, and chicken respectively. 2. In pan roasting, the EAA damaged most by heat was methionine (15%). When cooked after two months of frozen storage, lysine decreased most. 3. Higher pepsin digestibility was obtained by cooking rabbit meat after seasoned in alcohol, ginger juice, and other spices compared with various other cooking conditions without seasoning. The pepsin digestibility value was even higher for the seasoned meat than for the raw meat. 4. Among various meats tested the rabbit meat showed the lowest pepsin digestibility. 5. A simple measurement of released methionine could be used to determine relative digestibility instead of measuring $NH_2-N$ content after pepsin digestion. From all the results obtained in this study it can be concluded that rabbit meat is a good Protein food item when used fresh and stored properly to prevent rancidity problems. It is suggested to study further the peroxidation effect of unsaturated fatty acids on protein quality. This study was supported by the Ministry of Science and Technology in Korea.