• Journal of Applied Biological Chemistry
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• v.59 no.3
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• pp.173-178
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• 2016

Phenyllactic acid (PLA), which is a known antimicrobial compound, can be synthesized through the reduction of phenylpyruvic acid (PPA) by lactate dehydrogenase of lactic acid bacteria (LAB). PLA-producing LAB was isolated from coffee beans, and the isolated LAB was identified as Lactobacillus zeae Y44 by 16S rRNA gene sequence analysis. Cell-free supernatant (CFS) from L. zeae Y44 was assessed for both its capability to produce the antimicrobial compound PLA and its antifungal activity against three fungal pathogens (Rhizoctonia solani, Botrytis cinerea, and Colletotrichum aculatum). PLA concentration was found to be 4.21 mM in CFS when L. zeae Y44 was grown in MRS broth containing 5 mM PPA for 12 h. PLA production could be promoted by the supplementation with PPA and phenylalanine (Phe) in the MRS broth, but not affected by 4-hydroxy-phenylpyruvic acid, and inhibited by tyrosine as precursors. Antifungal activity assessment demonstrated that all fungal pathogens were sensitive to 5 % CFS (v/v) of L. zeae Y44 with average growth inhibitions ranging from 27.8 to 50.0 % (p<0.005), in which R. solani was the most sensitive with an inhibition of 50.0 %, followed by B. cinerea and C. aculatum. However, pH modification of CFS to pH 6.5 caused an extreme reduction in their antifungal activity. These results may indicate that the antifungal activity of CFS was caused by acidic compounds like PLA or organic acids rather than proteins or peptides molecules.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.301-305
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• 2002

The gene (ppaT) encoding Thermus caldophilus GK24 pyrophosphatase (Tca pyrophosphatase) was cloned and sequenced. The gene was found to contain an open reading frame encoding 175 amino acids with a calculated mass of 19,155 Da. The ppaT gene was expressed under the control of the tac promoter in Escherichia coli. The recombinant Tca pyrophosphatase was purified 21.4-fold with $56\%$ yield and specific activity of 25.7 U $mg^-1$, following a combination of heating (to denature the E. coli proteins) and one step of DEAE-Sephacel column chromatography. The native enzyme was found to have an approximate molecular mass of 110,000 Da and consisted of six subunits. The enzyme exhibited maximal activity at pH of 8.0-8.5 and was stable at $80-90^{\circ}C$. A divalent cation was absolutely required for the enzyme activity, with $Mg^2+$. being the most effective.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.9 no.2
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• pp.115-127
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• 1998

Laryngopharyngeal reflux(LPR) is one firm of the gastroesophageal reflux diseases(GERD). It is known to cause various kinds of otolaryngologic symptoms such as hoarseness, foreign body sensation in throat, chronic throat clearing, chronic cough, etc. Disease entities diagnosed by otolaryngologists as posterior laryngitis, globus pharyngeus should be suspected as LPR-related diseases. In this multi-center trial, we tried to evaluate the effect of cisapride(10mg tid) on LPR-related symptoms as the part I study(CIS-KOR-051) in 19 centers, and as the part II study(CIS-KOR-052) comparative evaluation of effect between cisapride(10mg tid) and ranitidine(150mg bid) on LPR-related symptoms in 4 centers. In part I study, efficacy of cisapride on LPR-related symptoms after 4 weeks was 53.5% and that of after 8weeks was 77.9% in per protocol(PPA) analysis group. In part II study, efficacy of the cisapride was much better than that of ranitidine not only from 8 weeks trial(p<0.001) but also from 4 weeks trial(p<0.021) in PPA group. In the multiple logistic regression analysis among the parameters which affect the efficacy of the treatment, cisapride prescribed group showed 10 times greater than that of ranitidine prescribed group(p<0.0001, Odds ratio : 10) in PPA group. LPR was proved by 24Hr double probe pHmetry in 13 patients out of 19 patients tested(68.4%). Thus these results indicated that inducing the improvement of motility functions could affect the amelioration of the LPR-related symptoms much better than reducing acid secretion from the stomach. And maybe it suggests that LPR-related symptoms mainly developed by the reduced motility functions of the esophagus and/or delayed gastric emptying.

• Nutritional Sciences
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• v.7 no.4
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• pp.241-246
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• 2004

This study investigated the influence of weight perception on weight management strategies including diet and exercise in Korean female adolescents. Junior (J) and senior (S) high school girls were divided in two groups; those who had $\leq$100% (BI) and > 100% (AI) of ideal weight (J-BI, n=376, 14.8 yr, 46.1 kg; J-AI, 11=128, 15.0 yr, 57.4 kg; S-BI, n=325, 17.4 yr, 50.1 kg; and S-AI, n=133, 17.5 yr, 58.2 kg, mean values). Questionnaires to assess weight perception, desire to lose weight, body image, eating behavior, weight control strategies and physical activity (PPA) were administered J-AI(9.4 kg) and S-AI(9.8 kg) desired to lose weight more than J-BI(2.5 kg) and S-BI(3.6 kg), respectively (p < 0.001). 85% of J-AI and 93% of S-AI perceived their weight being above average and 23% of J-BI and 34% of S-BI responded similarly (p < 0.001). Body dissatisfaction index (BDI) and eating attitude (EAT26) scores were lower in J-BI(9.7, 12.0) vs. J-AI(16.4, 14.7) and S-BI(12.4, 12.4) vs. S-AI(19.5, 15.4) (p < 0.001). However, PPA was not different for J-BI vs. J-AI, and S-BI vs. S-AL Only 17, 18, 9, and 15% of J.BI, J.AI, S-BI, and S-AI, respectively, exercised regularly. PPA and BDI were only slightly correlated in J-BI(r=0.194, p < 0.005) and S-BI(r=0.220, p < 0.005). Even that the majority of Korean female adolescents perceived they were heavy and desired to lose weight, appropriate exercise and physical activities were not practiced.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.4
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• pp.551-558
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• 2015

This study was carried out to evaluate the dietary threonine requirement by measuring the plasma free threonine and ammonia concentrations in rainbow trout, Oncorhynchus mykiss after dorsal aorta cannulation. A total of 70 fish (average initial weight $506{\pm}8.2g$) were randomly distributed into each of the 14 net cages (5 fish/cage). After 48 hours (h) of feed deprivation, each group was intubated at 1% body weight with one of the seven L-amino acid based diets containing graded levels of threonine (0.42%, 0.72%, 0.92%, 1.12%, 1.32%, 1.52%, or 1.82% of diet, dry matter basis). Blood samples were taken at 0, 5, and 24 h after intubation. Post-prandial plasma free threonine concentrations (PPthr) of fish 5 h after intubation with diets containing 1.32% or more threonine were significantly higher than those of fish intubated with diets containing 1.12% or less threonine (p<0.05). Post-absorptive free threonine concentrations (PAthr) after 24 h of intubation of the fish with diets containing 0.92% or more threonine were significantly higher than those of fish intubated with diets containing 0.72% or less threonine. Post-prandial plasma ammonia concentrations (PPA, 5 h after intubation) were not significantly different among fish intubated with diets containing 1.12% or less threonine, except the PPA of fish intubated with diet containing 0.42% threonine. Broken-line model analyses of PPthr, PAthr, and PPA indicated that the dietary threonine requirement of rainbow trout should be between 0.95% (2.71) and 1.07% (3.06) of diet (% of dietary protein on a dry matter basis).

• Journal of Auto-vehicle Safety Association
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• v.13 no.2
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• pp.30-34
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• 2021

Electrical failures and reliability problems of electronic components by ionic migration between adjacent device terminals have become an issue in automotive electronics. Especially unlike galvanic corrosion, ionic migration is occurred at high temperature and high humidity under applied electric field condition. Until now, although extensive studies of the ionic migrations dealing with PCBs, electrodes, and solders were reported, there is no study on the effect of insulation polymers and metallic fillers for ionic migration. In this research, therefore, ionic migration induced by the types and contents of polymers and metallic fillers, and variety conditions of temperature, humidity, and applied voltage was studied in detail. Ester and amide types of liquid crystal polymer (LCP) and poly (phthalamide) (PPA) were used as base polymers, respectively and compounded with the metallic fillers of Copper iodide (CuI), Zinc stearate (Zn-st), or Calcium stearate (Ca-st) in various compositions. The compounding polymers were fabricated in IPC-B-24 of SIR test coupon according to ISO 9455-17 with Cu electrodes for ionic migration test. While there is no change in LCP-based samples, ionic migration in PPA compounding sample with a high water absorption property was accelerated in the presence of 0.25 wt% or above of CuI at the environmental conditions of 85℃, 85% RH and 48V. The dendritic short-circuit growth of Cu caused by ionic migration between the electrodes on the surface of compounded polymers was systematically observed and analyzed by using optical microscopy and SEM (EDX).

• Journal of Electrochemical Science and Technology
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• v.13 no.3
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• pp.407-415
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• 2022

Surface coating of cathodes is an essential process for all-solid-state batteries (ASSBs) based on sulfide electrolytes as it efficiently suppresses interfacial reactions between oxide cathodes and sulfide electrolytes. Based on computational calculations, Li₃PO₄ has been suggested as a promising coating material because of its higher stability with sulfides and its optimal ionic conductivity. However, it has hardly been applied to the coating of ASSBs due to the absence of a suitable coating process, including the selection of source material that is compatible with ASSBs. In this study, polyphosphoric acid (PPA) and (NH₄)₂HPO₄ were used as source materials for preparing a Li₃PO₄ coating for ASSBs, and the properties of the coating layer and coated cathodes were compared. The Li₃PO₄ layer fabricated using the (NH₄)₂HPO₄ source was rough and inhomogeneous, which is not suitable for the protection of the cathodes. Moreover, the water-based coating solution with the (NH₄)₂HPO₄ source can deteriorate the electrochemical performance of high-Ni cathodes that are vulnerable to water. In contrast, when an alcohol-based solvent was used, the PPA source enabled the formation of a thin and homogeneous coating layer on the cathode surface. As a consequence, the ASSBs containing the Li₃PO₄-coated cathode prepared by the PPA source exhibited significantly enhanced discharge and rate capabilities compared to ASSBs containing a pristine cathode or Li₃PO₄-coated cathode prepared by the (NH₄)₂HPO₄ source.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.278-282
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• 2010

In this study, the antibacterial activity and component analysis of Persicaria perfoliata extracts were investigated. MIC (Minimum Inhibitory Concentration) values of ethyl acetate fraction from P. perfoliata on Escherichia coli, Propionibacterium acnes, and Staphylococcus aureus were 0.25%, equally. The results showed that the antibacterial activity of the ethyl acetate fraction was the highest in the S. aureus and P. acnes. Ethyl acetate fraction from P. perfoliata extracts showed 5 bands in TLC and 8 peaks in HPLC (320nm). In HPLC chromatogram of ethyl acetate fraction, first main peak 2 (24.99%) and peak 3 (22.65%) were identified as quercetin-3-o-glucuronide and isoquercitrin in the order of elution time. Also, in HPLC chromatogram of deglycosylated fraction, main peak 2 (76.93%) was identified as quercetin in the order of elution time. And these components are very effective as antioxidants. Thus, these results indicate that extract/fractions of P. perfoliata can be applicable to new functional cosmetics for antioxidant, antibacterial activity.

• Korean Journal of Plant Resources
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• v.34 no.5
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• pp.443-450
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• 2021

Peach flesh color is commercially important criteria for classification and has implications for nutritional quality. To breed new yellow-fleshed peach cultivar many cross seedlings and generations should be maintained. Therefore it is necessary to develop early selection molecular markers for screening cross seedlings and germplasm with economically important traits to increase breeding efficiency. For the comparison of transcription profiles in peach varieties with a different flesh color expression, two cDNA libraries were constructed. Differences in gene expression between yellow-fleshed peach cultivar, 'Changhowon Hwangdo' and white-fleshed peach cultivar, 'Mibaekdo' were analyzed by next-generation sequencing (NGS). Expressed sequence tag (EST) of clones from the two varieties was selected for nucleotide sequence determination and homology searches. Putative single nucleotide polymorphisms (SNPs) were screened from peach EST contigs by high resolution melting (HRM) analysis, SNP ID ppa002847m:cds and ppa002540m:cds displayed specific difference between 17 yellow-fleshed and 21 white-fleshed peach varieties. The SNP markers for distinguishing yellow and white fleshed peach varieties by HRM analysis offers the opportunity to use early selection. This SNP markers could be useful for marker assisted breeding and provide a good reference for relevant research on molecular mechanisms of color variation in peach varieties.

• Information Systems Review
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• v.25 no.3
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• pp.99-120
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• 2023

Courier services users' experience of violating privacy affects psychology and behavior of protecting personal privacy. Depending on what privacy infringement experience (PIE) of courier services users, learning about perceived privacy infringement incidents is made, recognition is formed, affection is formed, and behavior is appeared. This paradigm of changing in privacy psychologies of courier services users has an important impact on predicting responses of privacy protective action (PPA). In this study, a theoretical research framework are developed to explain the privacy protective action (PPA) of courier services users by applying attitude theory. Based on this framework, the relationships among past privacy infringement experience (PIE), perceived privacy risk (PPR), privacy concerns (i.e., concerns in unlicensed secondary use (CIUSU), concerns in information error (CIE), concerns in improper access (CIA), and concern in information collection (CIC), and privacy protective action (PPA) are analyzed. In this study, the proposed research model was surveyed by people with experience in using courier services and was analyzed for finding relationships among research variables using structured an equation modeling software, SMART-PLS. The empirical results show the causal relationships among PIE, PPR, privacy concerns (CIUSU, CIE, CIA, and CIC), and PPA. The results of this study provide useful theoretical implications for privacy management research in courier services, and practical implications for the development of courier services business model.