• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.379-386
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• 1989

The soy milk prepared from soy protein concentrate was treated with microbial protease or papain. Growth and acid production by Lactobacillus acidophilus in soy milk containing partially hydrolyzed proteins were investigated. Sensory evaluation of yogurt beverage prepared from protease treated soy milk was also performed. Protease treatment of soy milk enhanced acid production by lactic acid bacteria, particularly in case of microbial pretense and simultaneous treatment by two types of protease showed synergistic effect. pH and number of viable cells were not affected markedly by pretense treatment. Microbial pretense treatment up to 15 minutes or papain treatment up to 45 minutes enhanced acid production, but further treatment up to three hours did not affect the acidity markedly. rho sensory evaluation showed that overall acceptability and taste of soy yogurt beverage were slightly improved when soy milk was treated with microbial pretense of 0.2% or papain of 0.2%. The amount of non-protein nitrogen considerably increased by pretense treatment of 15 minutes and it increased gradually by further treatment up to three hours.

• Biomedical Science Letters
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• v.6 no.3
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• pp.209-221
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• 2000

The purpose of this study was to investigate the practical availability of pretense production that can be used at home after isolating Serratia sp.2000-1 which produced extracellular pretense from clinical specimen. Basic production conditions and partial enzymatic characteristics of pretense produced by Serratia sp. 2000-1 was as follows: The kind and concentration of carbohydrate, nitrogen and metal salts for optimal enzyme production condition were each identified as the concentration of 1.5% glucose, 2.0% CSP, and 0.1% CaCl$_2$, and the optimal temperature, time and initial pH for culture were each 3$0^{\circ}C$, 72 hours, and pH 8.0. The final enzymatic yeild that was purified by 3 steps with ammonium sulfate precipitation (45~80%), DEAE-cellulose column chromatography, and Sephadex G-200 gel chromatography was 14.4%, and enzyme inactivity rate increased approximately 291314s. The optimal temperature and pH for purified pretense activity were 35$^{\circ}C$ and pH 7.0~8.0, and purified pretense activity was relatively stable by 4$0^{\circ}C$ at pH 6~10 for 30 min, however heating at 6$0^{\circ}C$ for 30 min, it liminated detectable pretense activity. The pretense activity was activated by $Mg^{2+}$, $Ba^{2+}$, $Ca^{2+}$, Mn$^{2+}$, but inactiviaed by Hg$^{2+}$, Ag$^{2+}$, Cu$^{2+}$, and the pretense activity was inhibited strongly by SDS among enzyme activity inhibitors. Further study is required to evaluate the practical availability of pretense production that can be used at home by isolating Serratia sp. from more clinical specimen and examining pretense more in details.

• Korean Journal of Child Studies
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• v.25 no.6
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• pp.337-354
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• 2004

This study investigated the relationship between pretend play and comprehension of pretense by type of stipulated transformation among 2-and 4-year-olds children. Each child participated in pretend play with its mother for 10 minutes and in a stipulated task for comprehension of pretense. There was a significant difference in 2- and 4-year-olds in frequency and level of pretend play, and pretend play behavior was related to comprehension of pretense. Level of pretend play was positively related to comprehension of 'complexity' of stipulated transformations. This showed that there was significant relationship between development of pretend play and ability to comprehend pretense based on physical transformation.

• Parasites, Hosts and Diseases
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• v.41 no.3
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• pp.165-169
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• 2003

This study describes the characterization of 80 kDa pretense showing gelationlytic property among three pretenses in the excretory/secretory proteins (ESP) from Toxoplasma gondii. The pretense activity was detected in the ESP but not in the somatic extract of RH tachyzoites. This pretense was active only in the presence of calcium ion but not other divalent cationic ions such as $Cu^{2+},{\;}Zn^{2+},{\;}Mg^{2+},{\;}and{\;}$Mn^{2+}$, implying that $Ca^{2+}$ is critical factor for the activation of the protease. The 80 kDa pretense was optimally active at pH 7.5. Its gelatinolytic activity was maximal at $37^{\circ}C$, and significant level of enzyme activity of the pretense remained after heat treatment at $56^{\circ}C$ for 30 min or $100^{\circ}C$ for 10 min, This thermostable enzyme was strongly inhibited by metal chelators, i.e., EDTA, EGTA, and 11 10-phenanthroline. Thus, the 80 kDa pretense in the ESP secreted by T. gondii was classified as a calcium dependent neutral metalloprotease.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.26 no.1
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• pp.107-124
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• 2000

A bacterial strain No. HB-5, which was capable of producing a pretense in the culture conditions, was isolated from the soil . The pretense was purified from cultural filtrate of Bacillus sp. HB-5 by membrane ultrafiltration and DEAE- cellulose chromatography, gel filtration on Sephadex G-100. The molecular weight was estimated to be 60k4a. The optimal pH and temperature for the activity of the purified pretense pH were 11 and 5$0^{\circ}C$ , respectively. The enzyme was stable within a pH range 8-12 and up to 6$0^{\circ}C$ . The enzyme activity was highly inhibited by PMSF at 1mM. The proteolytic actions of pretense and papain on human epidermis keratins which are major protein impurities on the skin, were compared. The bacterial pretense degraded more effectively than papain. Product containing 2% protease exhibited 21% increase on the skin coloration index. These results suggest that cosmetic product containing pretense produced by Bacillus sp. HB-5 could remove the adherent keratin layer and then make a softer skin.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.496-501
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• 2006

This study was to isolate a bacterium producing a alkaline protease from mud flats of the west seaside of Korea and to investigate the biochemical analysis of the alkaline protease producing from the isolate. The isolate was named as Gelidibacter sp. HK-1 based on 16S rRNA sequence, Gram staining and the photograph of electron microsceope. Optimum temperature for growth and pretense production of the isolate was $25^{\circ}C$. Growth of the isolate was reached at stationary phase after 10hrs followed by inoculation. Maximum activity of protease produced from the isolate was shown after 14hrs. Optimum temperature and pH for the protease activity were $45^{\circ}C$ and pH 9, respectively. Molecular weight of the pretense was about 50KD and the partial amino acid sequence of the pretense was Ala-Try-Ala-Leu-Asn-Thr-Ser-Val-Thr-Glu-Thr-Phe-Ala-Lys. The partial amino acid sequences of the protease showed significant homology with a pretense produced from Streptomyces avermitilis.

• Korean Journal of Child Studies
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• v.23 no.4
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• pp.1-20
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• 2002

The subjects of this study of the development of concepts of pretense and of false beliefs were 168 3-, 4-, 5-, and 6-year-olds. There were 2 significant main effects for age and type of task both for pretend and false belief tasks. The older children performed pretend tasks and false belief tasks at a higher level than the younger children. Performance on pretend tasks was higher with alternatives than without them. On false belief tasks, there were differences in performance among the change of location, the change of content and the second order false belief tasks. Correlations between understanding of pretense and false beliefs were relatively high. These results suggest that the relationship between children's understanding of pretense and false belief varied by types of tasks.

• Journal of Microbiology
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• v.41 no.1
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• pp.58-62
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• 2003

An extracellular pretense of Bacillus amyloliquefaciens S94 was purified to apparent homogeneity. The enzyme activity was strongly inhibited by general inhibitor for serine protease, PMSF, suggesting that the enzyme is a serine pretense. The purified enzyme activity was inhibited by leucine peptidase inhibitor, bestatin, suggesting that the enzyme is a leucine endopeptidase. The maximum proteolytic activity against different protein substrates occurred at pH 10, 45$^{\circ}C$ (protein substrate) and pH 8, 45$^{\circ}C$ (synthetic substrate). The purified enzyme was specific in that it readily hydrolyBed substrates with Leu or Lys residues at P$_1$ site. The pretense had characteristics of a cold-adapted protein, which was more active for the hydrolysis of synthetic substrate in the range of 15$^{\circ}C$ to 45$^{\circ}C$, specially at low temperature.

• Preventive Nutrition and Food Science
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• v.7 no.2
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• pp.123-127
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• 2002

Ninety nine extracts from Korean plants were screened for their inhibitory activities on human immunodeficiency virus (HIV) type 1 pretense by an HPLC method. The pretense inhibitory activities were determined by incubating the extracts in reaction mixtures containing pretense and substrate (His-Lys-Ala-Arg-Val-Leu-(p-NO$_2$- Phe)-Glu-Ala-Nle-Ser-NH$_2$) to perform proteolytic cleavage reactions. Of the extracts tested, the water extracts of Viburnum awabuki (stem and leaves) and Distylium racemosum (leaves) had the highest pretense inhibitory activities at a concentration of 100ug/mL. Activity-guided fractionation, revealed that the n-butanol fraction of the V. awabuki extract and the ethyl acetate fraction from the D. racemosum extract had the greatest inhibitory activity on HIV-1 pretense.

• Food Science of Animal Resources
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• v.24 no.4
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• pp.326-328
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• 2004

Domestic pear has been reported that it contained a pretense, which used for tenderizer of meat, however no researches for optimum level of the enzyme with maximum tenderness effect have been studied. Thus, this study was peformed to determine the optimum level of a protease for meat tenderness. Moisture contents (％) of domestic pears was determined. A pretense was homogenized in a mixer and centrifuged at 10,000 G for 1hr. After taken the supernatant, dialysis was conducted to remove salts and sugars, and freeze-dried. Then, various level (0.05, 0.1 and 0.2％) of the purified pretense were added to pork loins (3cm thickness). Then, pork samples were boiled at 80 for 12 min in a water bath to reach the interval temperature of 71 and chilled in an ice. Moisture contents (％) of domestic pears ranged from 87.2 and 87.8％. No differences in cooking loss of pork meats were observed (p>0.05) among various levels of a pretense. After centrifugation, the protein concentrations of a protease showed from 5.96 $\mu\textrm{g}$/fmL to 7.25 $\mu\textrm{g}$/mL. Increased level of a pretense up to 0.1％ reduced (p<0.05) the shear value (kg/g), however no further reduction of shear value was observed at the level of higher than 0.1％ of the purified pretense. The approximate molecular weight of the pretense analysed by sodium-dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was 30 kDa. These results suggest that the optimum level of a pretense for the maximum effect of meat tenderness is above 0.1％. Further research will be peformed to determine the effect of various domestic pears and ingredients, such as salt and phosphate, on meat tenderness.