• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.138-145
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• 2013

This study was conducted to evaluate the microbiological contamination on commonly used hand towels in the child care centers and to investigate the toxin gene and toxin production ability of food-borne pathogens. A total of 22 commonly used hand towels including 7 for before use and 15 for during use were tested. The average number of total aerobic bacteria and fungi were 6.2 log CFU/100 $cm^2$ and 4.1 log CFU/100 $cm^2$. Coliform bacteria were detected in 4 out of 7 before used towels (57.1%) and all of during used towels (100%). These results showed that the sanitary conditions of hand towels in the child care centers should be improved promptly. Among the pathogenic bacteria, Staph. aureus and B. cereus without Salmonella spp. were detected in 5 (22.7%) and 11 (50.0%) out of 22 hand towels. All of Staphy. aureus isolated in this study did not possess any toxin genes and did not produce enterotoxin. The detection rate of hblC, hblD, and hblA toxin genes in B. cereus was 72.7, 72.7, and 54.5% respectively. The possession rate of nheA, nheB, and nheC toxin genes showed 81.8, 72.7, and 54.5% respectively. The cytK and entFM toxin genes were presented at 45.5 and 90.0% in B. cereus. The HBL was detected in 8 out of 11 B. cereus isolates (72.7%) and 5 B. cereus isolates produced NHE (45.5%). Ten out of eleven B. cereus isolates (90.9%) produced one or more enterotoxin such as HBL and NHE. From the results, using a private hand towel or paper towel is required to prevent the cross-contamination between commonly used hand towel and children's hands in the child care center.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.737-744
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• 2001

This study was carried to investigate the changes in physical and chemical properties during preparation of Yukwa. Protein content of glutinous rice was decreased during soaking time and acid and pH values were increased while contents of lipid and ash were not changed. Particle size distribution showed thate average particle size of 7 days soaking treatment smaller than those of 3 days and starch damage of glutinous rice flour was increased during soaking time. The major flavor components after soaking were found ethyl ester acetic acid, ethanol, 2-butan -ol, 2-methyl 1-propanol, 1-butanol, 3-methyl 1-butanol and 1-pentanol, propanoic acid. Content of acetic acid and butanoic acid were rapidly increased during soaking time. Results for ratio of storage modulus(G') and loss modulus(G') in glutinous rice flour dough indicated $tan{\delta}$ was increased for a while and decreased as frequency increased. G' value was very similar with G' value after steaming which means rubber-like property while G' and G' value were changed after during storage time. Treatment at $-20^{\circ}C$ had the highest hardness for cutting degree of dough. There was no difference in color value between different water contents. Hardness of Bandegi (sheet) was decreased as water content increased and the highest popping value was obtained at 18% of water contents. Adding 3% soaked bean had higher redness value of Yukwa and lower value in yellowness.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.27-34
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• 2008

This study investigated the anti-hypertensive effect of Phyllostachys pubescens culm extract (PCE) by examining its effects on renal angiotensin-converting enzyme (ACE) inhibition and blood pressure using the spontaneously hypertensive rat (SHR) system. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured weekly for 8 weeks. Also, total antioxidant capacity and protein oxidation of tissues were examined by plasma Trolox Equivalent Antioxidant Capacity assay (TEAC) and hepatic protein carbonyl values, respectively. Twenty male SHR were randomly divided into four groups: PCE50, PCE100, and PCE500 (50, 100, and 500 mg of PCE per kilogram bodyweight daily, respectively), and control group. At week 2, the SBP in all PCE groups appeared to be significantly lower than the control (p<0.05), whereas the DBP were not different until week 4 (p<0.05). At week 8, SBP in the PCE500 was lower by 20% than the control. PCE groups considerably suppressed ACE dose-dependently compared with the control. Plasma TEAC and hepatic protein carbonyl values indicated increased antioxidative activity due to the PCE feed. No adverse effect was observed on the liver of SHR as there was no difference for the GOT and GPT values among the groups. Results of this study suggest that ACE inhibition may be one possible mechanism for the blood pressure lowering effect of PCE; thus, long term consumption of PCE may be beneficial in preventing high blood pressure along with the increased antioxidative status.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.1
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• pp.33-39
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• 2009

To develop a new natural whitening agent for cosmetics, we investigated the inhibitory effects of Pogostemon cablin Bentham extracts (PCE) and its active component on melanogenesis. PCE showed ROS scavenging activities in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and xanthine/xanthine oxidase system with the $IC_{50}$ values of $24.2{\pm}2.85{\mu}g/mL$ and $IC_{50}=118{\pm}0.43{\mu}g/mL$, respectively. PCE reduced melanin contents of B16 melanoma cells in a dose-dependant manner and decreased to about 23 % at a concentration of $20{\mu}g/mL$ without cell cytotoxicity (below $100{\mu}g/mL$). And the PCE reduced intracellular tyrosinase activity about 18 % at concentration of $50{\mu}g/mL$. We purified one active compound from PCE and identified its structure. It was identified as patchouli alcohol, sesquiterpene family, by 1H-NMR, $13_C$-NMR, and Mass analysis. Patchouli alcohol also inhibited ROS scavenging activities in DPPH radical and xanthine/xanthine oxidase system with the $IC_{50}$ values of $3.14{\pm}0.12{\mu}g/mL$ and $49{\pm}3.24{\mu}g/mL$, respectively. Patchouli alcohol inhibited melanin synthesis in a dose dependent manner ($IC_{50}=3.9{\mu}g/mL$). And the patchouli alcohol reduced intracellular tyrosinase activity about 40 % at concentration of $10{\mu}g/mL$. Patchouli alcohol inhibited tyrosinase and TRP-2 expression at protein level. These results suggest that PCE and patchouli alcohol reduced melanin formation by the inhibited of tyrosinase activity and expression in B16 melanoma cells. Therefore, we suggest that PCE could be used as a useful whitening agent.

• Food Science and Preservation
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• v.22 no.5
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• pp.727-734
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• 2015

In this study, three GRAS (generally recognized as safety) strain was isolated from Doenjang and Cheonggukjang and identified as a protease-producing microorganism, following the appearance of a clear zone around its colony when cultured on a medium containing skim milk. Based on an analysis of the nucleotide sequence of 16S ribosomal RNA, the strains wereas identified as Bacillus amyloliquefaciens and wereas therefore named Bacillus amyloliquefaciens CDD5, Bacillus amyloliquefaciens CPD4, and Bacillus amyloliquefaciens CGD3. Here, we analyzed the protease and ${\alpha}$-glucosidase inhibitory activities of the three B. amyloliquefaciens strains. Among the isolated strains, B. amyloliquefaciens CGD3 exhibited the highest protease activity (9.21 U/mL, 24 hr). The protease activities of B. amyloliquefaciens CDD5 and B. amyloliquefaciens CPD4 reached 1.14 U/mL and 8.02 U/mL, respectively, at 48 hr. The proteases from the three B. amyloliquefaciens strains showed the highest activities within a pH range of 8.0-9.0 at $50^{\circ}C$, and casein was found to be the preferred substrate on evaluating enzyme activity in the substrate specificity assay. The B. amyloliquefaciens strains exhibited maximal growth when the nutrient broth medium had an initial pH within the range of 5.0-10.0, 6-9% sodium chloride (NaCl), and 5% glucose. B. amyloliquefaciens CDD5 exhibited a low ${\alpha}$-glucosidase inhibition rate (5.32%), whereas B. amyloliquefaciens CPD4 and B. amyloliquefaciens CGD3 exhibited relatively higher inhibition rates of 96.89% and 97.55%, respectively.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.217-225
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• 2004

This study was carried out to reduce the loss of frozen dough quality during frozen storage. Using response surface method, ascorbic acid 160.4 ppm, L-cysteine 63.1 ppm, and SSL 0.6% were found to be optimum, with xanthan gum 0.3% (formula A) and Ultra tex-3 5% (formula B) added as cryoprotectants. During frozen storage at $-20^{\circ}C$, control rapidly deteriorated after 4 weeks, while formulas A and B showed slight deterioration with immutable quality after 10 weeks.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.332-338
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• 2009

A xylan-decomposing bacterium, HY-20, was isolated from the gut of a honeybee, Apis mellifera, and identified as Bacillus sp. The extracellular GH11 xylanase (XylP) gene (687-bp) of strain HY-20 encoded a protein of 228 amino acids with a deduced molecular mass of 25,522 Da and a calculated pI of 9.33. The primary structure of XylP was 97% identical to that of B. pumilus xylanase (GenBank accession no.: AY526092) that has not been characterized yet. The recombinant His-tagged enzyme (rXylP) overexpressed in Escherichia coli BL21 harboring pET-28a(+)/xylP was purified to electrophoretic homogeneity by cation exchange and gel permeation chromatographies. The purified enzyme exhibited the highest catalytic activity toward birchwood xylan at pH 6.5 and $50^{\circ}C$ and retained approximately 50% of its original activity when pre-incubated at $55^{\circ}C$ for 15 min. The recombinant enzyme was completely inactivated by $Hg^{2+}$ (1 mM) and N-bromosuccinimide (5 mM), while its activity was slightly stimulated by approximately 10% in the presence of $Mn^{2+}$ (1 mM), $Fe^{2+}$ (1 mM), and sodium azide (5 mM). rXylP was able to efficiently degrade various polymeric xylose-based substrates but PNP-sugar derivatives and glucose-based polymers were not susceptible to the enzyme.

• Journal of Life Science
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• v.16 no.1
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• pp.22-29
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• 2006

Effect of microbial products made of Bacillus stearothermophilus DL-3 on growth of chickens and pigs was investigated. Two types of microbial product were made in this study. One is the microbial product made of culture broth of B. stearothemophilus DL-3 and rice bran which named as the microbial product A. The other is the microbial product made of culture broth of B. stearothermophilus DL-3, apple pomace, soybean pomace and rice bran which named as the microbial product B. Chickens were divided into three groups and each group was fed with $100\%$ general feed, $90\%$ general feed supplemented with $10\%$ microbial product A or $90\%$ general feed supplemented with $10\%$ microbial product B. The average chicken weight of each group was $41.1{\pm}2.5g,\;41.6{\pm}3.2g\;and\;42.3{\pm}2.9g$ and those after 28 days was $547.7{\pm}91.7g,\;560.1{\pm}17.2g\;and\;562.2{\pm}32.5g$, respectively. The average weight gain for each group was 506.6 g, 518.6 g and 519.9 g, respectively, and weight increases of groups fed with $90\%$ general feeder and $10\%$ microbial product A and B were $2.4\%\;and\;2.6\%$ higher than the group fed with $100\%$ general feed. Pigs were also divided into three groups and each group was fed like chickens. The average weight of each group was $9.3{\pm}1.0kg,\;9.4{\pm}1.1kg\;and\;9.6{\pm}1.0kg$ and those after 37 days was $19.3{\pm}4.1kg,\;20.2{\pm}3.9kg\;and\;20.8{\pm}4.2kg$, respectively. The average Weight gain for each group was 10.65 kg, 10.82 kg and 11.20 kg, respectively, and weight increases of groups fed with $90\%$ general feeder and $10\%$ microbial product A and B were $1.6\%$ and $5.2\%$ higher than the group fed with $100\%$ general feed.

• Pediatric Infection and Vaccine
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• v.9 no.1
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• pp.79-84
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• 2002

Purpose : About 41% of obtained group A streptococci in the 1998 was reported as erythromycin-resistant streptococci in Seoul, Korea. The most common T serotype was T12, followed by T4 and T28. We'd like to monitor the serological changes and antibiotic sensitivity test of Streptococcus pyogenes obtained from the patients with pharyngotonsillitis and invasive diseases from 1999 through 2001. Also, it could be proposed to choose the proper antibiotic selection in the area where the rate of erythromycin-resistant streptococci is high. Methods : From Jan. 1999 to Oct. 2001, 208 isolates of group A streptococci were collected from inpatients and outpatients with pharyngotonsillitis, scarlet fever, and invasive infections in Seoul and Southern part of peninsula. All isolates were serotyped by T-agglutination, minimum inhibitory concentrations(MICs) which were determined by agar dilution methods, according to the guidelines of the National Committee for Clinical Laboratory Standards (NCCLS). Results : The most common T serotype was T12(29.8%), followed by T1(23.1%), T4 (14.9%). T1 was prominent serotype compared with previous year. T serotyping, among 25 isolates obtained from the patients with scarlet fever in Southern part of peninsula mostly, was T12, T1, and T4 in order of frequency. All the isolates tested were susceptible to penicillin, cefprozil, vancomycin, ceftriaxone, and chloramphenicol. However, 23 isolates(14.2%) was resistant to erythromycin and 18 isolates(11.1%) was resistant to clarithromycin. Serotype T12 was found to be the most resistant serotype to erythromycin and/or clarithromycin. Conclusion : High rate of erythromycin-resistant streptococci which surveyed in 1998 were reduced to 14.2% in this study. We should have to further evaluate the reason of decreased resistant strains and consider the resistant strains of streptococci in choosing the antibiotics. There was no serological characteristics according to the types of disease entities. Between the serologic distributions in Seoul and the Southern part of peninsula area are same, we could presume that the serological typing of strains obtained over the country may be not different.

• Journal of Life Science
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• v.18 no.4
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• pp.522-529
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• 2008

High-temperature requirement A2(HtrA2) has been known as a human homologue of bacterial HtrA that has a molecular chaperone function. HtrA2 is mitochondrial serine protease that plays a significant role in regulating the apoptosis; however, the physiological function of HtrA2 still remains elusive. To establish experimental system for the investigation of new insights into the function of HtrA2 in mammalian cells, we first obtained $HtrA2^{+/+}$ and $HtrA2^{-/-}$ MEF cells lines and identified those cells based on the expression pattern and subcellular localization of HtrA2, using immunoblot and biochemical assays. Additionally, we observed that the morphological characteristics of $HtrA2^{-/-}$ MEF cells are different form those of $HtrA2^{+/+}$ MEF cells, showing a rounded shape instead of a typical fibroblast-like shape. Growth rate of $HtrA2^{-/-}$ MEF cells was also 1.4-fold higher than that of $HtrA2^{+/+}$ MEF cells at 36 hours. Furthermore, we verified both MEF cell lines induced caspsase-dependent cell death in response to apoptotic stimuli such as heat shock, staurosporine, and rotenone. The relationship between HtrA2 and heat shock-induced cell death is the first demonstration of the research field of HtrA2. Our study suggests that those MEF cell lines are suitable reagents to further investigate the molecular mechanism by which HtrA2 regulates the balance between cell death and survival.