• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.831-838
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• 1996

This study was undertaken in order to elucidate the effects of raw, roast and steamed buckwheat on fecal protein, Pancreas weight, the activities of $\alpha-amylase,$ chymotrypsin and lipase 91 the pancreas, and $\alpha-amylase,$ chymotrypsin and trypsin activities of the feces in streptozotocin-induced diabetic rats. Fecal proteins of raw, roast and steamed buckwheat diabetic groups were increased up to 99%, 91%, 103%, respectively compared to those of the diabetic control group. Feeding of buckwheat diet increased pancreas weight, especially raw buckwheat diabetic group(p<0.05). Pancreatic chymo-trypsin activity was decreased in buckwheat diabetic groups compared to diabetic control group, wheres any significant difference was observed in $\alpha-amylase$ and lipase activities. Fecal chymotrypsin activi-ty was significantly increased in all buckwheat diabetic groups. Fecal trypsin activity was increased in roast buckwheat diabetic groups compared to diabetic control group and fecal $\alpha-amylase$ activity in buckwheat diabetic group was not significantly different. These results suggest that feeding of buckwheat diet enhances the impaired exocrine pancreatic function of diabetic rat.

• KSBB Journal
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• v.9 no.3
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• pp.312-318
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• 1994

The esterification of Ac-Tyr-OH was carried out in one-phase system containing ethanol by ${\alpha}$-chymotrypsin. The results of the esterification reaction are as follows. Chitin-${\alpha}$-chymotrypsin complex was found to be an effective catalyst for the esterlfication of Ac-Tyr-OH in ethanol organic solvent. The optimal conditions for the esterification were chitn/${\alpha}$-chymotrypsin ratio, 20(w/w); reaction temp., $35^{\circ}C$; reaction pH, 8.0; reaction time, 24 hrs. Also, addition of chitin in water/water-miscible organic solvent was effective for the stability of the enzyme. The esterification yield, Km and Vmax under optimal conditions were 93%, 3.093mM and 1.088mM/mg/hr, respectively.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.676-681
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• 2001

This study was carried out to evaluate the quality characteristics of frozen soy yogurts prepared with different proteolytic enzymes and starter culture. The viable cell counts of lactic acid bacteria in frozen soy yogurts were measured $10^8$ CFU/g by the single culture method, while $10^9$ CFU/g by the mixed culture method except ${\alpha}-chymotrypsin$ treatment. The viable cell counts of lactic acid bacteria did not decrease after freezing for 30 min in ice cream maker. The lactic acid bacteria from the mixed culture showed better bile acid tolerance than those from the single culture. The lactic acid bacteria from the frozen soy yogurt prepared with ${\alpha}-chymotrypsin$ and mixed culture of Bifidobacterium bifidum and Lactobacillus bulgaricus showed better acid tolerance and bile acid tolerance. The highest(73.45%) overrun was observed in the frozen soy yogurt treated with ${\alpha}-chymotrypsin$ and mixed culture of B. bifidum and L. bulgaricus. The melt-down percent was higher in the single culture than the mixed culture. In sensory test, the frozen soy yogurt prepared with ${\alpha}-chymotrypsin$ and mixed culture of B. bifidum and L. bulgaricus was the most desirable, the highest scores in sourness, bitterness and mouthfeel.

• Tuberculosis and Respiratory Diseases
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• v.43 no.3
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• pp.359-366
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• 1996

Background : Eosinophilic leukocytes are prominent cellular participants in the pathogenesis of allergic disease and asthma. Chemotaxis is still a very useful method in evaluating the response of human eosinophil to novel modulators. Degranulated mast cells and activated T lymphocytes are responsible for the pathophysiology of asthma and tryptase is one of most important proteases released after activation of mast cells. The purpose of this study was to investigate the actions of trypsin and chymotrypsin on eosinophils in terms of chemotaxis and activation. Method : Eosinophils were isolated by negative immunoselection from the peripheral blood of atopic donors. Chemotaxis was studied by using micro-Boyden chambers and ECP release was assayed by fluoroimmunoassay. Results : Eosinophil showed a chemotactic response to trypsin. Maximal chemotactic response was with $1000{\mu}g/ml$ trypsin ($56.52{\pm}14.50$/HPF) which was comparable to PAP. But chymotrypsin showed no significant chemotactic response to eosinophils. Trypsin at the concentration of 10, 100, $1000{\mu}g/ml$ induced secretion of ECP, which at the concentration of $10{\mu}g/ml$ represented about 2.7 times of the spontaneous rate of release. Soybean protease inhibitor reduced trypsin induced ECP release. Conclusion : Trypsin can induce chemotactic response to eosinophils and activation of eosinophils that can induce secretion of ECP. On the contrary, chymotrypsin showed no direct effect on eosinophils. We propose a role of trypsin on the chemotaxis and activation of eosinophils.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.2
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• pp.154-162
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• 2006

Cheese analogs using lipoxygenase-defected soymilk and ${\alpha}$-chymotrypsin modified soy protein isolate (SPI) were prepared. Color, textural properties, sensory attributes and melting spreadability of cheese analogs were evaluated and compared with mozzarella cheese, and relationships between textural properties, sensory attributes and melting spreadability of cheese analogs were analyzed. Off-flavors were not mostly discriminated. Cheese analogs containing 10% SPI untreated and containing 6% and 8% SPI treated by ${\alpha}$-chymotrypsin in ${\Delta}E$ value of color were the most similar to mozzarella cheese. Quality characteristics and melting spreadability of cheese analogs were highly affected and improved by ${\alpha}$-chymotrypsin modification. Sensory attributes and melting spreadability of cheese analogs containing 6% SPI treated by ${\alpha}$-chymotrypsin were the most similar to mozzarella cheese, while in textural properties, cheese analogs containing 10% SPI were the most similar with mozzarella cheese. Hardness in sensory attributes was highly positively correlated with hardness (r>0.65), adhesiveness (r>0.56), chewiness (r>0.77) and gumminess (r>0.76) in textural properties, while it was highly negatively correlated with melting spreadability (r>-0.68).

• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.52-67
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• 1998

The investigative research on the mammalian milk purely consisted of the physiological quality of lactoferrin was conducted to reveal the antimicrobial ativity of specifically functional foods with antibiotic characteristics as a basic data in food manufacturing. Bovine lactoferrin were isolated from raw milk samples, and was digested with pepsin, trypsin and chymotrypsin. It was necessary then to separate and purify lactoferrin from bovine raw milk, and in order to analyze the antimicrobial activity of the enzyme-treated bovine lactoferrin in their required quantitative fraction. Afterwards Escherichia coli and Staphylococcus aureus was incubated in it. It was that investigated to enzyme-treated fractions molecular weight and the peptide fragment with antimicrobial effect. 1. The purity of enzyme-treated bovine lactoferrin(BLF) was tested by SDS-PAGE. As a results of 12% SDS-PAGE assay, pepsin-treated LF did not exhibited band until if reaches 14 KDa, while trypsin and chymotrypsin treated LF, known to contain the non-digestive lactoferrin exhibited band at a molecular weight of 33 KDa. 2. Bovine lactoferrin was sucessfully purified through the use of Sephadex G-50 Column. In order to assay LF through the Sephadex G-50 column chromatography, the digestive bovine lactoferrin (BLFs) was eluted with a linear gradient of 0.05% Tris-HCl. When the gel-filtration analysis, pepsin, trypsin and chymotrypsin treatments of BLF fragments was showed 2, 3, and 2 peak, respectively. The results of the HPLC analysis confirmed that had a non-digestive lactoferrin receptor, and trypsin and chymotrypsin treated BLFs has an antimicrobial effect. 3. To measure the strength of the antimicrobial effect of enzyme treated lactoferrin it was compared to the antimicrobial activity taking place at the incubated Escherichia coli and Staphylococcus aureus. This might explain the resistance of the microorganisms for peptide fragment. The pepsin-treated of bovine lactoferrin was markedly reduced by incubation of the cells. Trypsin-treated of BLF was similar to chymotrypsin-treated of BLF. However, trypsin and chymotrypsin treatments of BLFs were showed the antimicrobial effect until eight hours incubation for native bovine lactoferrin. Therefore the enzyme-treated lactoferrin have an antimicrobial effect even non-digestive lactoferrin. 4. The digestive bovine lactoferrin fragments assay was carried out by the use of Sephadex G-50 column chromatography and SDS-PAGE. The pepsin and chymotrypsin-treated fragments has a low molecular weight and trypsin-treated lactoferrin was only showed a band. It was described that characteristics of digestive protein. It appeared that there may be a relation between virulence and resistance to enzyme-treated BLF.

• Korean journal of food and cookery science
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• v.16 no.2
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• pp.151-159
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• 2000

The effects of bromelain and $\alpha$-chymotrypsin treatments on the functional properties(foaming capacity, foaming stability, emulsifying capacity, and emulsifying stability) of soy protein isolate(SPI) and the addition of various sweeteners(sucrose, sorbitol, xylitol) on the quality attributes(viscosity, overrun ratio, melt-down property, and sensory characteristic) of soy ice cream were studied. SPI was more effectively hydrolyzed with $\alpha$-chymotrypsin than bromelain, resulting in a better foaming and emulsifying capacity. Adding xylitol could significantly improve the viscosity, overrun and melt-down property of soy ice creams while the effect was the lowest in the sucrose addition. Bromelain treatment caused a lower apparent viscosity of SPI suspension compared with $\alpha$-chymotrypsin treatment and untreated. The overrun ratios of the soy ice cream prepared with bromelain and $\alpha$-chymotrypsin treated SPI were 18.9∼25.9% and 24.9∼40.3%, respectively as a result of freezing with agitation for 20 min in an ice cream maker. Comparatively, untreated SPI could bring only 15.8∼21.4% overrun ratios after operating for 15 min. The bromelain treatment caused high melt-down tendency of the product while soy ice cream with untreated SPI showed an opposite trend. In sensory characteristics, no significant differences in the strength of beany flavor were noted among the samples. Sweetness, bitter taste, icy feel, and mouthfeel of the product were greatly affected by the enzyme-treatment of SPI. Soy ice cream added with xylitol after $\alpha$-chymotrypsin treatment was the most acceptable among all samples.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1822-1829
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• 2003

Porcine colostrum and milk were separated into the acid-soluble and casein fractions by acidification followed by centrifuge. The acid-soluble fraction of porcine colostrum was further separated by liquid chromatography and anisotropic membrane filtration. Trypsin and chymotrypsin inhibitory capacity in porcine colostrum, milk and their components was determined by incubating bovine trypsin or chymotrypsin in a medium containing their corresponding substrates with or without addition of various amounts of porcine colostrum, porcine milk or their components. The inhibition of insulin-like growth factor I (IGF-I) and epidermal growth factor (EGF) degradation in pig small intestinal contents by porcine colostrum was measured by incubating iodinated IGF-I or EGF with the intestinal contents with or without addition of porcine colostrum. Degradation of labeled IGF-I or EGF was determined by monitoring the generation of radioactivity soluble in 30% trichloroacetic acid (TCA). The results showed that porcine colostrum had high levels of trypsin and chymotrypsin inhibitory activity and increased the stability of IGF-I and EGF in pig intestinal contents. The inhibitory activity declined rapidly during lactation. It was also found that trypsin and chymotrypsin inhibitory activity and the inhibition on IGF-I and EGF degradation in the acid-soluble fraction were higher than that in the casein fraction. Heat-resistance study indicated that trypsin inhibitors in porcine colostrum survived heat treatments of $100^{\circ}C$ water bath for up to 10 min, but exposure to boiling water bath for 30 min significantly decreased the inhibitory activity. Compared with the trypsin inhibitors, the chymotrypsin inhibitors were more heatsensitive. Separation of the acid-soluble fraction of porcine colostrum by liquid chromatography and anisotropic membrane filtration revealed that the trypsin and chymotrypsin inhibitory capacity was mainly due to a group of small proteins with molecular weight of 10,000-50,000. In conclusion, the present study confirmed the existence of high levels of protease inhibitors in porcine colostrum, and the inhibition of porcine colostrum on degradation of milk-borne growth factors in the pig small intestinal tract was demonstrated for the first time.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.310-316
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• 1999

BBPI contents in domestic soybean and soybean products were investigated by the measurement of chymotrypsin inhibiting activity(C.I.A) and competitive ELISA method. In order to produce polyclonal antibody, BBPI was purified from soybean trypsin-chymotrypsin inhibitor by ion exchange chromatography and electrophoretic gel slicing. Rabbit anti-BBPI polyclonal antibody was produced with the purified BBPI as immunogen. This antibody showed relatively specific binding to BBPI and then used for the establishment of competitive ELISA method to measure BBPI contents in extracts of soybean and soybean products. The standard curve for the measurement of BBPI in soybean extracts was drawn up within the range 0.03 to $30\;{\mu}g/ml$ of BBPI. The C.I.A. and BBPI contents of 12 soybean cultivars were $8,462{\sim}12,428\;U/g$ and $482{\sim}692\;mg%$, respectively. The C.I.A. and BBPI contents were not detected in most of soybean products except soybean sprouts, which contained $10,695{\sim}13,249\;U/g$ of C.I.A. and $529{\sim}803\;mg%$ of BBPI.

• Clinical and Experimental Reproductive Medicine
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• v.25 no.2
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• pp.207-216
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• 1998

Certain types of somatic cells, as well as follicular cumulus cells associating with mammalian oocytes, are known to produce beneficial effects on in vitro fertilization and pre implantation development of mammalian eggs when they are present in oocyte culture medium. To investigate the nature of the effects of somatic cells, the resistance of mouse oocytes against chymotrypsin treatment was examined after culture within various cell conditioned media. When mouse oocytes matured for 17-18 hr in the presence of cumulus cells were treated with 1 % chymotrypsin, half of them remained still alive even after 240 min $(t_{50}>240.0)$. In contrast half of mouse oocytes cultured without cumulus cells underwent degeneration within 65.0 min $(t_{50}=65.0{\pm}13.2min)$ of the same treatment. To see if the effects were duc to the secretory products of cumulus cells, mouse cumulus cells were cultured for 20 hr in medium containing 0.4% BSA and the supernatant of culture medium (conditioned medium) was taken. After maturation in the cumulus cell conditioned medium, mouse oocytes exhibited $t_{50}=190.0{\pm}10.8$ min upon chymotrypsin treatment whereas half of oocytes cultured without conditioned medium degenerated within 25.5 min. Human granulosa cell conditioned medium gave similar effects such that oocytes matured in conditioned medium exhibited $t_{50}=183.3{\pm}19.1$ min while $t_50$ of control group oocytes was $60.0{\pm}6.8$ min, Oocytes matured in vero cell conditioned medium exhibited $t_{50}=196.7{\pm}8.8$ min. On the other hand, amniotic cell conditioned medium resulted in the chymotrypsin resistance of $t_{50}=80.0{\pm}8.4$ min which was not statistically different from the control value of $t_{50}=48.0{\pm}13.2$ min. Based upon these results, it is suggested that certain somatic cell types including cumulus cells might change the biochemical properties of mouse oocyte membrane during meiotic maturation as revealed by the enhanced resistance against chymotrypsin treatment. Such effects of somatic cells appear to be mediated via the secretory products rather than direct communication between somatic cells and oocytes.