• The Korean Journal of Food And Nutrition
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• v.27 no.2
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• pp.225-230
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• 2014

The objective of this study was to investigate the effects of soy hydrolysate fractions on appetite suppression and ghrelin releasing. In a short-term experiment, the cumulative food intake and serum ghrelin level were decreased significantly (p<0.05) during a 4-hr period after the interperitoneal injection of soy hydrolysate fractions (0.5, 1 g/kg BW), following a 12-hr period of food deprivation. In a long-term experiment, food efficiency ratio (FER) was also reduced significantly (p<0.05), when soy hydrolysate fractions (0.5, 1% in drinking water) were given orally for 8 wks. Therefore, we found that soy hydrolysate fractions affected food intake through appetite and ghrelin releasing in short-term and long-term experiments. In conclusion, this study indicated that soy hydrolysate fractions would diminish the sensation of hunger by reducing the secretion of orexigenic factors such as ghrelin that send satiety signals to the brain, terminating food intake.

• Food Science and Preservation
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• v.12 no.5
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• pp.460-464
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• 2005

In order to produce functional soy hydrolysates, we investigated the characteristics of soy hydrolysates prepared with 4 kinds of commercial proteases. The yield was high in protease(B), in which 43.2% soy flour and 61.6% SPI were obtained. The solubility and the contents of total phenolic compound were greatly increased by the treatment of protease(B) along with protease(C). The calcium intolerance was improved after the protease(B) treatment in soy flour or Soybean Protein isolate (SPI). Consideration for the physicochemical characteristics including yield, protease(B) has potential application for the production of soy hydrolysates. After the protease treatment, the beany flavor of soy flour became weak and the bitter taste was strong in both soy flour and SPI. However, there was no difference of beany flavor and bitter taste among delete protease hydrolysates. Nevertheless, further modifications and improvements to the sensory characteristics would be required for the development of a range of products with the hydrolysate.

• Applied Biological Chemistry
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• v.40 no.5
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• pp.404-408
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• 1997

Enzymatically hydrolyzed vegetable protein (eHVP) was produced from soy protein using proteases, and the physicochemical properties were examined. Soy protein hydrolysate of 6% protein and 50% degree of hydrolysis was useful for the base of savory ingredients. The Maillard-reacted and flavoring compound-added hydrolysate had improved flavor. It was for enzymatically hydrolyzed soy sauces and dehydrated seasonings. ISP hydrolysate of low molecular weight $(MW{\sim}250)$ and high protein content (85%) was suitable for special uses such as infant diets, sports nutrition, and medical diets. The eHVP gave no limitation of dosage in the formulation as a flavor enhancer. The byproduct of protein hydrolysis was found to have high content of fiber (21%) and to have potential for the use as dietary fiber or bulking agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.229-235
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• 2004

Soy protein was hydrolyzed by 5 different pretenses and determinated antimicrobial activity of each hydrolysate. The soy protein hydrolysate treated by pretense from Aspergillus saitoi showed the highest antimicrobial activity among the protease studied and was used for further analysis. Soy protein hydrolysate was fractionated by ultrafiltration for M.W. 10,000,3,000 and 1,000. The M.W 1,000∼3,000 showed the highest antimicrobial activity. The minimum inhibition concentrations of obtained fraction were 0.5∼0.8 mg/mL for gram positive and negative microbials, and its activity was even observed after heating at 121$^{\circ}C$ for 10 min, suggesting that hydrolyzed protein having antimicrobial activity is quite heat-stable. Reverse-phase HPLC was further applied to separate the fraction and 8 peaks were found. Each 8 peaks were separated and pooled and measured antimicrobial activity. Among them, retention time of peak at 16.02 min showed the prominent antimicrobial activity.

• KSBB Journal
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• v.10 no.2
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• pp.137-142
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• 1995

When Escherichia coli W, which is able to utilize sucrose as a carbon source, harboring a high-copy-number plasmid (pSYL105) containing the Alcaligenes eultrophus polyhydroxyalkanoate(PHA) biosynthetic genes was cultured in a defined medium, the final poly(3-hydroxybutyric acid), PHB, concentration obtained was as low as $0.21g/\ell$. Ten different complex nitrogen sources were, therefore, examined for their ability to enhance PHB synthesis when supplemented to a defined medium. Addition of tryptone, casamino acids, casein hydrolysate, or soy bean hydrolysate enhanced PHB synthesis most significantly, resulting in more than 10 times higher PHB concentration compared with that obtained in a defined medium. Furthermore, PHB yield on sucrose was also increased by more than a 10 fold by the addition of these complex nitrogen sources, which suggested that PHB might be efficiently produced by the recombinant E. coli W(pSYL105) using sucrose as a carbon source.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.784-787
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• 1997

Enzymatically hydrolyzed soy sauce(eHSS) was prepared by the treatment of defatted soy flake using two types of proteases, followed by maillard reaction and formulation with some ingredients. The eHSS was mixed with fermented soy sauce(FSS) to make enzymatically hydrolyzed mixed soy sauce(eHMSS). The properties and sensory characteristics were evaluated and compared with commercially available soy sauces. The control of salt and total nitrogen contents in eHSS and eHMSS was easy, and the production of soy sauce of low salt and high protein was possible. However, the free amino acid content of eHSS was lower than FSS. due to lower degree of hydrolysis. In sensory evaluation, the eHSS have no loss taste and overall acceptance than FSS. Consequently, the eHSS and eHMSS have the potential for use with FSS to produce high quality soy sauce of low salt and high protein contents.

• Food Industry And Nutrition
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• v.4 no.3
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• pp.66-72
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• 1999

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.4
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• pp.470-475
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• 1993

The imitation sauce was prepared by using the enzymatic hydrolysate of cod skin gelatin and its product quality was also compared with three kinds of soy sauce on the market sensually. The major molecular weight of the hydrolysate used in this study was 5, 800Da and glycine, proline, serine, alanine, hydroxyproline, glutamic acid, and aspartic acid having sweet taste accounted for 65.9% of the total amino acid being in the hydrolysate. The imitation sauce was prepared the mixture of the liquor and fermented sauce (8 : 2 = v : v), where the liquor was prepared by dissolving with 10.0g the hydrolysate, 10.0g NaCl, 3.0g sucrose, 0.5g monosodium glutamate, 0.1g caramel powder, 3.0$m\ell$ fermented vinegar, 0.05g garlic powder, 0.1g black pepper powder, and 0.2g licorice powder in 100.0$m\ell$ water, boiling for 5min and filtrating with cheesecloth. From the result of sensory evaluation, the imitation sauce was at least equal to three kinds of soy sauce in product quality.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.105-108
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• 2003

To enhance the performance of a serum-free medium (SFM) for human thrombopoietin (hTPO) production in suspension cultures of recombinant Chinese hamster ovary (rCHO) cells, several low-cost hydrolysates such as yeast hydrolysate (YH), soy hydrolysate, wheat gluten hydrolysate and rice hydrolysate were tested as medium additives. Among various hydrolysates tested, the positive effect of YH on hTPO production was most significant. When 5 g/L YH was added to SFM, the maximum hTPO concentration in batch culture was 40.41 ${\mu}g/mL$, which is 11.5 times higher than that in SFM without YH supplementation. This enhanced hTPO production in YH-supplemented SFM was obtained by the combined effect of enhanced $q_{hTPO}$ and increased culture longevity. In addition YH supplementation did not affect in vivo biological activity of hTPO. Taken together, the results obtained demonstrate the potential of YH as a medium additive for hTPO production in serum-free suspension cultures of rCHO cells.

• Bulletin of Food Technology
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• v.17 no.3
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• pp.69-74
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• 2004

A soy protein hydrolysate was found to inhibit rat platelet aggregation induced by ADP, an aggregating agent. To find out its principal antiplatelet peptide(s), the soy protein hydrolysate was separated successively by gel filtration chromatography, revere-phase HPLC, and cation exchange HPLC. During the course of separation, we observed that most fractions had antiplatelet effects, which suggests that most peptides have some degree of antiplatelet effect. Following the inhibitory fractions, we purified and identified two new peptides, SSGE and DEE, by LC-electrospray ionization MS and peptide equencing. Both peptides were highly hydrophilic. The concentrations to obtain 50% inhibition ($IC_50$) of the aggregation intensity were approximately $\458muM$ and $\485muM$, respectively, for SSGE and DEE.