• Journal of Periodontal and Implant Science
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• v.38 no.sup2
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• pp.343-354
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• 2008

Purpose: Aggregatibacter actinomycetemcomitans is associated with localized aggressive periodontitis. It produces cytolethal distending toxin (CDT), which induces cell cycle arrest in the G2/M phase. The CDT holotoxin is composed of CdtA, CdtB, and CdtC. CdtB has structural homology to human DNase I and is an active component of the CDT complex acting as a DNase. In particular, the pattern homology seen in the CdtB subunit has been associated with specific DNase I residues involved in enzyme catalysis, DNA binding, and metal ion binding. So, to study the functions and regulation of recombinant CdtB, we made up a quantity of functional recombinant CdtB and tested it in relation to the metal ion effect. Materials and Methods: We constructed the pET28a-cdtB plasmid from A. actinomycetemcomitans Y4 by genomic DNA PCR and expressed it in the BL21 (DE3) Escherichia coli system. We obtained the functional recombinant CdtB by the refolding system using the dialysis method and then analyzed the DNase activity and investigated the metal ion effect from plasmid digestion. Results: The recombinant CdtB subunit was expressed as the inclusion bodies. We were able to obtain functional recombinant CdtB subunit using refolding system. We confirmed that our refolded recombinant CdtB had DNase activity and was influenced by the metal ions $Mg^{2+}$ and $Ca^{2+}$. Conclusion: We suggest that the factors influencing recombinant CdtB may contribute to CDT associated diseases, such as periodontitis, endocarditic, meningitis, and osteomyelitis.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.710-713
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• 1989

Process cheeses were made in a laboratory with natural cheese, water, butter, and emulsifying salts varying in quantity and temperature. With the emulsifying salts, the hardness of process cheese varied from 286 to 580g, the pH values 5.1-5.9 and the solid content 56.8-63.7%. The water activity measured 0.96-0.98, the crude protein content 27.1-27.7%, the crude fat content 58.3-59.9% and the ratio of protein to fat 45.3-47.5%. The various properties of samples showed no natable difference. Increasing the water addition, the hardness and the ratio of the protein to fat decreased, while both the pH values and the water activity increased. With increasing the melting temperatures from 75 to 80, 85, 90 and $95^{\circ}C$. The other indices showed no remarkable differences among the samples.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.3
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• pp.99-108
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• 2021

The present study examines the overall manufacturing status of local wetsuit makers, problems in the manufacturing process, and future research tasks. The study revealed that most manufacturers use neoprene fabric of varying thickness, depending on the body part. Normally, 3 mm-thick fabric is utilized for high-activity body parts and 5 mm-thick fabric is used for high-activity areas requiring thermal insulation. In terms of the manufacturing method, the tools and manufacturing processes used by companies were found to be similar. However, because of the nature of wetsuits requiring a more complicated manufacturing method than that of general clothing, there were some differences in the manufacturing method processes from company to company, such as bonding and ease treatments. According to wetsuit manufacturers, they make incisions in consideration of the body's curvature and the overall shape and design of the wetsuit when developing patterns. For example, most answered that they preform the wrist and ankle parts, where the body's curvature is obvious. On the question regarding the "difficult manufacturing process", the most frequent response was the "bonding" process. Most manufacturers were found to focus on designs that can improve mobility and clothing fit, and commonly experienced low-order quantity as an operational difficulty. As for the question on the wetsuit-related technology needed in the future, the "development of various designs" was the most frequent answer, followed by the "development of lightweight and diverse materials".

• Journal of Environmental Science International
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• v.32 no.11
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• pp.777-788
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• 2023

Potato common scab disease is caused by pathogens belonging to Streptomyces spp. and results in a serious yield loss worldwide. Despite decades of research aimed at disease management, a definitive control method remains undiscovered. This study aims to explore the correlation between the C/N ratio and urea application with potato common scab pathogen dynamics and disease severity. We applied sawdust with a high C/N ratio and urea into the soil prior to potato cropping, both in pot and field experiments. Disease severity assessments and quantification of the TxtB gene were conducted at the harvest stage. Furthermore, culture experiments were performed to assess the direct impact of urea on the pathogen. Our findings revealed that higher disease severity was correlated with a high C/N ratio application and pathogenic gene quantity. Urea exhibited a direct influence on S. scabiei activity, reducing the disease severity in pot experiments. However, the effects of urea application on disease suppression in the conductive field were inconclusive. Although the results of urea application experiments displayed inconsistencies between pot and field trials, urea worked as the control to suppress S. scabiei activity. Further investigations are needed under various field conditions to confirm these findings.

• Food Science of Animal Resources
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• v.44 no.2
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• pp.464-482
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• 2024

This study aimed to determine the effects of humectants on moisture content, water activity, tenderness, color, microbiological analysis, protein denaturation, and oxidation of jerky. A thorough search for papers published in scientific journals that examined the impacts of humectants on jerky was carried out using Web of Science, Google Scholar, PubMed, and Science Direct. Only 14 studies matched inclusion requirements. They were used in the meta-analysis to synthesise quantitative findings. In the current investigation, jerky produced with beef, poultry, goat, or pork was used. The standardised mean difference (SMD) between treatments with humectants and controls was examined to investigate the effects of humectants using random-effects models. Heterogeneity was investigated using meta-regression. A subgroup analysis was carried out for significant factors. Results revealed that the addition of humectants had no significant impact on water activity, pH, fat, ash, CIE L^*, or CIE a^* (p>0.05). However, humectant addition significantly increased moisture (SMD=1.28, p<0.05), CIE b^* (SMD=1.67, p<0.05), and overall acceptability (SMD=1.73, p<0.05). It significantly decreased metmyoglobin (SMD=-0.96, p<0.05), shear force (SMD=-0.84, p<0.05), and protein (SMD=-1.61, p<0.05). However, it was difficult to get a firm conclusion about how humectants affected the myofibrillar fragmentation index, total plate count, and 2-thiobarbituric acid-reactive substances because there were fewer than ten studies. To sum up, the proper use of humectants in jerky demands careful attention to both type and quantity, needing a delicate balancing act with other contributing factors.

• Applied Biological Chemistry
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• v.37 no.2
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• pp.65-71
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• 1994

Chungkook-Jang was produced by fermenting Bacillus licheniformis CN-115. The changes of chemical composition, enzyme activity, and amino acids during the fermentation were investigated. The proximate composition was shown irregular fluctuation phenomenon during the fermentation, but only the moisture tended some reducing during the fermentation just after steaming. The content of amino nitrogen was increased radically after the 36 hours of fermentation and became the highest level at 18.072 mg/g at the 60 hours of it. In accordance with the fermentation of Chungkook-Jang, pH got to the 8.39 at 60 hours with increasing, protease activity was increased according to the fermentation and acid and neutral protease activity was reduced after being reached at the highest activity at 48 hours. The most suitable pH was 6.5 and temperature was $35^{\circ}C$ for dissolution-activated of protein in the process of fermentation of Chungkook-Jang. The content of water soluble protein and the content of salt soluble protein were increased at continuously according to the fermentation time of Chungkook-Jang the largest quantity. The molecular weight of water soluble protein of Chungkook-Jang fermented for 48 hours was about 19,000. The amino acids of water soluble protein just after steaming were totally 16 kinds and proline was amino acid and them was in series by glutamic acid and serine in that ordered. The amino acids salt soluble protein, just after steaming were totally 16 kinds and was the largest quantity phenylalanine, glutamic acid and aspartic acid and aspartic acid in that order.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.1
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• pp.115-125
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• 2000

In recent years a great deal of information has accumulated for livestock on vitamin. function, metabolism and supplemental needs. The role of the antioxidant "vitamins" (carotenoids, vitamin E and vitamin C) in immunity and health of livestock has been a fruitful area of research. These nutrients play important roles in animal health by inactivating harmful free radicals produced through normal cellular activity and from various stressors. Both in vitro and in vivo studies showed that these antioxidant vitamins generally enhance different aspects of cellular and noncellular immunity. A compromised immune system will result in reduced animal production efficiency through increased susceptibility to diseases, thereby leading to increased animal morbidity and mortality. Vitamin E has been shown to increase performance of feedlot cattle and to increase immune response for ruminant health, including being beneficial for mastitis control. Vitamin E given to finishing cattle at higher than National Research Council (NRC) requirements dramatically maintained the red color (oxymyoglobin) compared with the oxidized metmyoglobin of beef. Under commercial livestock and poultry production conditions, vitamin allowances higher than NRC requirements may be needed to allow optimum performance. Generally, the optimum vitamin supplementation level is the quantity that achieves the best growth rate, feed utilization, health (including immune competency), and provides adequate body reserves.

• Industrial Engineering and Management Systems
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• v.12 no.4
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• pp.317-329
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• 2013

In recent years, for the purpose of solving the problem regarding environment protection and resource saving, certain measures and policies have been promoted to establish a green supply chains (GSC) with material flows from collection of used products to reuse of recycled parts in production of products. In this study, we propose an optimal operation of the GSC while considering the collection incentive of the used products and quality for recycling of used products. Two types of decision-making approaches are used for product quantity, collection incentive of used products and lower limit of quality level of reusable parts in the used products for recycling in the GSC. One is the decision-making under an independent policy in decentralized supply chains where a retailer and a manufacturer make decisions so as to maximize profits individually. The other is the decision-making under a cooperative policy in centralized supply chains where a retailer and a manufacturer make decisions cooperatively so as to maximize the whole system's profit. Additionally, we also discuss supply chain coordination as a manufacturer-retailer partnership based on profit sharing. Furthermore, we show the effect of the quality of the reusable parts on the optimal decisions. The collection incentive of the used products was found to bring more profitability to the GSC activity.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.4
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• pp.343-346
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• 1990

A study was conducted to determine the effect of prostaglandin $F_2$ alpha ($PGF_2$ alpha) on the reaction time and seminal characteristics of buffalo bulls. Semen was collected from three Murrah bulls in three periods: pre-treatment, treatment and post-treatment. During the treatment period each bull was administered 2 ml $PGF_2$ alpha (Synchrocept, Fenprostalene) im, 1 hour prior to semen collection. In the post-treatment, semen was collected 7 days after the last injection of $PGF_2$. Semen samples were evaluated immediately after collection. Pre-collection injection of $PGF_2$ alpha has no significant effect on reaction time, semen volume, percentage motility, sperm concentration and total number of sperms per ejaculate. Fluctuations in semen color and consistency were observed. There is a significant (p<0.05) increase in the mean percentage of normal spermatozoa during the treatment and post treatment periods. Likewise, administration of PG results into a significant (p<0.05) rise on the average percentage of live sperms but this effect was not manifested in the post-treatment period. Improvement in mass activity was observed during the treatment and post-treatment periods.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1459-1464
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• 2004

The purpose of this research was to investigate the potential use of cheese whey protein (CWP), a cheese by-product. The physiological activity of calcium-binding peptides in CWP may be used as a food additive that prevents bone disorders. This research also examined the characteristics of calcium-binding peptides. After the CWP was heat treated, it was hydrolyzed by trypsin. Then calcium-binding peptides were separated and purified by ion-exchange chromatography and reverse phase HPLC, respectively. To examine the characteristics of the purified calcium-binding peptides, amino acid composition and amino acid sequence were analyzed. Calcium-binding peptides with a small molecular weight of about 1.4 to 3.4 kDa were identified in the fraction that was flowed out from 0.25 M NaCl step gradient by ion-exchange chromatography of tryptic hydrolysates. The results of the amino acid analysis revealed that glutamic acid in a calcium-binding site took up most part of the amino acids including a quantity of proline, leucine and lysine. The amino acid sequence of calcium-binding peptides showed Phe-Leu-Asp-Asp-Asp-Leu-Thr-Asp and Ile-Leu-Asp-Lys from $\alpha$-LA and Ile-Pro-Ala-Val-Phe-Lys and Val-Tyr-Val-Glu-Glu-Leu-Lys from ${\beta}$-LG.