• Journal of Microbiology and Biotechnology
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• v.13 no.4
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• pp.522-528
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• 2003

The growth responses of Phellodendron amurense root-derived materials against seven intestinal bacteria were examined, using an impregnated paper disk agar diffusion method and spectrometric method under $O_2$-free condition. The biologically active constituent of the P. amurense root extract was characterized as berberine chloride ($C_{20}H_{18}NO_{41}Cl$) using various spectroscopic analyses. The growth responses varied depending on the bacterial strain, chemicals, and dose tested. At 1 mg/disk, berberine chloride strongly inhibited the growth of Clostridium perfringens, and moderately inhibited the growth of Escherichia coli and Streptococcus mutans without any adverse effects on the growth of three lactic acid-bacteria (Bifidobacterium bifidum, B. longum, and Lactobacillus acidophilus). The structure-activity relationship revealed that berberine chloride exhibited more growth-inhibiting activity against C. perfringens, E. coli, and S. mutans than berberine iodide and berberine sulfate. These results, therefore, indicate that the growth-inhibiting activity of the three berberines was much more pronounced as chloridated analogue than iodided and sulphated analogues. As for the morphological effect caused by 1 mg/disk of berberine chloride, most strains of C. perfringens were damaged and killed, indicating that berberine chloride showed a strong inhibition against C. perfringens. As naturally occurring growth-inhibiting agents, the P. amurense root-derived materials described could be useful as a preventive agent against diseases caused by harmful intestinal bacteria such as clostridia.

• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.2
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• pp.56-61
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• 2015

Rutin is an important bioflavonoid that is consumed in the daily diet. This study compared the functional components of rutin from various silkworm species using a gene database with those of rutin produced by silkworms selectively bred through cross-combinations. We made comparisons between the geographical origin and species of silkworm using a gene database and discovered that rutin activity was ranked in the following order by species, Chinese (C5)> miscellaneous varieties (Jamsaeng 1 Ho) >Japanese (Jam 115) > European (E58) >Korean (Sun 3 ho). However, rutin levels with respect to various genetic traits (blood color, silk color, and egg color) were consistent. In order to study rutin changes that occurred during the cross breeding of the silkworm gene, we bred cross-combinations utilizing Jam 115 and the 4051 silkworms. In conclusion, in order to provide information about the constituents of functional materials contained in silkworm powder, it is imperative that silkworm cross breeding occurs so that the database of functional materials extracted from silkworms will expand.

• International Journal of Industrial Entomology and Biomaterials
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• v.29 no.2
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• pp.162-168
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• 2014

1-Deoxynojirimycin(1-DNJ or DNJ), a component in silkworm powder, prevents glucose from being absorbed into the bloodstream from the small intestine by inhibiting ${\alpha}$-glucosidase activity. This study compared the functional components of 1-DNJ from various silkworm species using a gene database with those of 1-DNJ produced by silkworms bred through cross-combinations. We utilized comparisons of geographical origins and species of silkworms using a gene database and discovered that 1-DNJ activity was ranked in the following order by species, Japanese (SK-1) > Chinese (C48) > European (Rock191). 1-DNJ constituted varying percentages of silkworm organs in the following order, blood > epithelial tissue > body fat > silk glands. With regard to sex, 1-DNJ, levels were higher in males than females. However, 1-DNJ levels with respect to various genetic traits (blood color, silk color, and egg color) were consistent. In order to study 1-DNJ changes that occurred during cross breeding of the silkworm gene, we bred cross-combinations utilizing SK-1 and C48 silkworms. In conclusion, in order to provide information about the constituents of functional materials contained in silkworm powder, it is imperative that silkworm cross breeding occurs so that the database of functional materials extracted from silkworms will expand.

• Journal of Microbiology and Biotechnology
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• v.13 no.6
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• pp.969-975
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• 2003

Two conserved amino acid residues in the extra sugar-binding space near the catalytic site of Thermus maltogenic amylase (ThMA) were analyzed for their role in the hydrolysis and transglycosylation activity of the enzyme. Site-directed mutagenesis was carried out by replacing N33l with a lysine (N331K), E332 with a histidine (E332H), or by replacing both residues at the same time (N331K/E332H). The measured $K_m$ values indicated that affinities toward all substrates tested, including starch, pullulan, ${\beta}-cyclomaltodextrin$, and acarbose, were lower in all the mutants compared to that of wild-type ThMA, leading to reduced hydrolysis activity. In addition, the lower ratio of transglycosylation to hydrolysis in the mutants compared to that in the wild-type ThMA indicated that these mutants preferred hydrolysis to the transglycosylation reaction. These results demonstrated that the conserved dipeptide at 331 and 332 of ThMA is directly involved in the formation and accumulation of transfer products by accommodating acceptor sugar molecules.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.251-251
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• 2017

This study was performed to select the soil covering materials for winter safety of Cynanchum wilfordii Hemsley and to investigate the effect on the growth after overwinter. Soil covering materials such as vinyl, rice straw, lagging cover, vinyl+lagging cover, and non-covering were investigated how effect on overwintering rate, growth and yield of Cynanchum wilfordii Hemsley. In changes of soil temperature according to the soil covering materials, non-covering treatment was recorded the highest to $26.7^{\circ}C$, and lagging cover and rice straw showed little change of soil temperature with 9.2 and $9.3^{\circ}C$, respectively. Regrowth rates of early growth after overwinter were lowered in the order as rice straw > vinly+lagging cover > lagging cover > vinyl > non-covering. From the above-ground growth by soil covering materials, vine length showed similar growth in all treatments except vinyl covering and stem diameter exhibited the thicker pattern in vinyl and lagging cover, and there was no significant difference among treatments in number of branch. Flowering period is recorded July 30 in all treatments and ripening period is October 16. Yield of seed production is showed the best in vinyl+lagging cover with $25g/m^2$. Root weight and root length for subterranean growth showed no significant differences among all treatments. Yield is produced the highest in vinyl+lagging cover with 433kg/10a and the next to lagging cover with 431kg/10a. In comparison with incomes, lagging cover earned to 9,882 thousand won/10a, showed the effect on income enlargement to 21%, compare to that of the non-covering.

• International Journal of Industrial Entomology and Biomaterials
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• v.40 no.2
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• pp.33-40
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• 2020

Recently mulberry has been commercialized but it loses its marketability rapidly after harvest. In this study, characteristics of mulberry were examined at different storage temperature after harvest using the typical Korean mulberry cultivars. Postharvest spoilage fungi on the various mulberry cultivars, Cheongilppong, Daeshim, and Gwasang No. 2 was observed 2, 2, and 1 d, respectively, after harvest at 28℃. However, at 4℃, the day was 8, 7, and 4 d, respectively. At 28℃ storage condition, the weight loss behavior of mulberry did not showed significantly different among them. However, at 4℃ storage condition, mulberry Cheongilppong loses its weight rapidly compared to Daeshim and Gwasang No. 2. Sugar content of mulberry stored at 4℃ was nearly constant, but stored at 28℃ decreased with storage time. The acidity of mulberry slightly decreased with storage time and then increased. Juice leakage of frozen mulberry leaked abruptly within 6 h from the fruit body and then flattened at 25℃. The results of our study, the postharvest characteristics of mulberry were affected by mulberry cultivar and need to further study to increase the shelf life.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.124-129
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• 2015

We have previously characterized the complete fibroin light chain gene from one of the silkworm race Baegokjam (Bombyx mori) and found two variable regions (FibL1, intron 2 ~ 3; FibL2, intron 6) with the primer sets designed to cover these variable regions. In this study, we tested the utility of these variable regions as genetic markers for classifying silkworm races. For the purpose, Europian races (Q, PK), Chinese races (C26, C31), Japanese races (N15, N9), and tropical races (SA2, SA5) were used in this experiment. The polymorphism of the FibL1 and FibL2 were divided into two and three types, respectively. The combination of the FibL1 and FibL2 polymorphisms were constant within the same races. The result suggest that the primer sets designed from two variable regions of fibroin light chain gene may be useful as the genetic markers for silkworm races.

• Journal of Sericultural and Entomological Science
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• v.53 no.2
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• pp.118-123
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• 2015

The structural transition of silk protein has been induced by various method including alcohol treatment. To know the effect of alcohol concentration on silk beads conformation, silk beads were prepared in different alcohol concentration (100%, 70%, and 50%) and then examined the infrared spectra of silk beads. Silk beads prepared in 100% alcohol showed at $1265cm^{-1}$ attributed ${\beta}-sheet$ conformation and did not showed a characteristic absorption peak from model drug. However, silk beads in 70% and 50% alcohol showed some peaks originated from model drug including $2933cm^{-1}$, $1069cm^{-1}$, and $973cm^{-1}$. These results means that the micro-environment of silk beads was affected by alcohol concentration.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.122-125
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• 2012

This study was aimed for a development of a useful gene promoter which has a transcript expressional specificity in the early embryonic period of the silkworm, Bombyx mori. To select a useful gene expressed in the early embryonic stage, we constructed and analyzed a PCR-base subtraction cDNA library. In subtractive hybridization analysis, we confirmed four clones as differently expressed genes(BmNanos-like, BmNanos-P, BmNanos-O, BmVasa mRNAs). Northern hybridization and real time PCR results reveled that the BmNanos-like gene promoter is suitable for the silkworm transgenic vector system. Further defined studies on molecular functions and biological roles of their promoters will give us well-fined information and its application.

• Food Science of Animal Resources
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• v.44 no.1
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• pp.165-177
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• 2024

Volatile compounds (VOCs) are an important factor affecting meat quality. However, the characteristic VOCs in different parts of donkey meat remain unknown. Accordingly, this study represents a preliminary investigation of VOCs to differentiate between different cuts of donkey meat by using headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) combined with chemometrics analysis. The results showed that the 31 VOCs identified in donkey meat, ketones, alcohols, aldehydes, and esters were the predominant categories. A total of 10 VOCs with relative odor activity values ≥1 were found to be characteristic of donkey meat, including pentanone, hexanal, nonanal, octanal, and 3-methylbutanal. The VOC profiles in different parts of donkey meat were well differentiated using three- and two-dimensional fingerprint maps. Nine differential VOCs that represent potential markers to discriminate different parts of donkey meat were identified by chemometrics analysis. These include 2-butanone, 2-pentanone, and 2-heptanone. Thus, the VOC profiles in donkey meat and specific VOCs in different parts of donkey meat were revealed by HS-GC-IMS combined with chemometrics, whcih provided a basis and method of investigating the characteristic VOCs and quality control of donkey meat.