• Korean Journal of Microbiology
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• v.28 no.3
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• pp.210-218
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• 1990

The survival and transfer of chromosomal genes coding for the synthesis of amino acids (threonine, tryptophan, histidine, leucine, methionine) and of plasmid-borne genes coding for resistance to antibiotics (chloramphenicol, kanamycin, erythromycin) by transformation in sterile and nonsterile soil (the soil was amended to 12% vol/vol with the clay mineral, montmorillonite) was studied. In pure culture, the numbers of vegetative cells of the Bacillus subtilis strains decreased by 1 to 1.5 orders of magnitude within one week, but spores of each strain showed lesser decreases. In sterile soil, the populations of vegetative cells and spores decreased by 1.5 to 3 orders of magnitude within 2 to 4 days and then showed little additional decreased. The transformation frequencies (number of transformants/numbers of donors and recipients) of individual amino acid-genes invitro ranged from $1.3{\pm}0.6{\times}10^{-6}$ to $6.0{\pm}2.36{\times}10^{-6}$, of two amino acid-genes from $8.5{\pm}0.7{\times}10^{-8}$ to $3.1{\pm}0.6{\times}10^{-7}$, and of the antibiotic-resistance genes from $1.5{\pm} 0.2{\itmes} 10^{-7}$ to $1.4{\pm} 0.4{\times} 10^{-5}$ . In sterile soil, the frequencies of transfer of individual amino acid-genes ranged from $2.0{\times} 10^{-7}$ to $2.0{\times} 10^{-5}$ and of the antibiotic-resistance genes from $2.0{\times} 10^{-7}$ to $9.4{\pm} 4.7{\times} 10^{-6}$. The transfer of two amino acid-genes in sterile soil was detected at a frequency of $2.0{\times} 10^{-6}$ to $4.5{\times} 10^{-6}$, but only in three instances. The transformation frequencies of antibiotic-resistance genes in nonsterile soil were essentially similar to those in sterile soil. However, to detect transformants in nonsterile soil, higher concentrations of antibiotics were needed, as the result of the large numbers of indigenous soil bacteria resistant to the concentration of antibiotics used in the sterile soil and in vitro studies. The results of these studies show that genes can be transferred by transformation in soil and that this mechanism of transfer must be considered in risk assessment of the release of genetically engineered microorganisms to the environment.

• Journal of the Korean Home Economics Association
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• v.29 no.4
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• pp.25-35
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• 1991

This study was carried out to determine the proximate composition, amino acids and fatty acids contents and changes of physicochemical characteristics of each oil extracted from Spanish and Virginia type peanuts grown in Korea roasted at 110, 120, 130 and 14$0^{\circ}C$ for 2 minutes. 1. The moisture contents of raw Spanish and Virginia type peanuts were 6.5~6.8% respectively. The crude ash and reduced sugar contents of raw Spanish and Virginia type peanuts were 2.3% and 16.5% and the crude protein content was 27.0% in Spanish type peanuts and was aproximately 1% higher than in Virginia type peanut. The protein content was 25.7%~26.7% in Virginia type peanut roasted at 110, 120, 130 and 14$0^{\circ}C$. The crude fat content of Virginia type peanut was 46.0% which was aproximately 1% higher than that of Spanish type. But four kinds of oils content were 51.3%~51.8% in Spanish type peanut roasted at 110, 120, 130 and 14$0^{\circ}C$, which was about 2% higher than those of Virginia type. 2. Amino acids existed in peanut were glutamie acid, arginine, aspartic acid, leucine, glycine, phenylalanine, proline-lysine, tyrosine, valine and isoleucine, etc mainly. But methionine and threonine contents were very low. The content of glutamic acid was the highest in 71.6-81.7mg among amino acids. Glutamic acid content of Virginia type peanut was about 12% higher than that of Spanish type peanut. Total amino acid content was 441.8mg/g in Virginia type peanut and that was 16% higher than that of Spanish type peanut. The lysine content of Spanish and Virginia type peanuts roasted at 14$0^{\circ}C$ were 24% and 13%, these were lower than those of peanuts roasted at 11$0^{\circ}C$. 3. Main fatty acids of raw Spanish and Virginia type peanut oils were oleic(40.99-46.58%), linoleic(33.21-38.82%) and palmitic acid(9.72-11.58). Linoleic acid content of raw Virginia type peanuts was 5.6% higher than that of raw Spanish type peanut. And the oleic acid content of Spanish and Virginia type peanuts roasted at 11$0^{\circ}C$, 12$0^{\circ}C$, 13$0^{\circ}C$ and 14$0^{\circ}C$ was 50-53% and 41-43% respectively. Linoleic acid content of Spanish and Virginia type peanuts roasted at same temperatures as the former was about 28-31% and 37-38% respectively. That linoleic acid content of roasted peanuts was lower than that of raw peanuts. Linoleic acid content of raw and roasted Virginia type peanut, were higher than that of Spanish type peanuts. 4. Acid value and peroxide value of oils extracted from roasted Spanish and Virginia type peanuts were much higher than those of oils extracted from raw peanuts. The maximum AVs of oils extracted from Spanish and Virginia type roasted peanuts were samples roasted at 12$0^{\circ}C$and those AVs were 0.50 and 0.63 respectively. And the maximum POVs of oils extracted from Spanish and Virginia type roasted peanuts were samples roasted at 12$0^{\circ}C$ also and those POVs were 26.8 and 32.8 meq/kg. oil respectively. Acid value and peroxide value of oils extracted from roasted peanuts were increased with increasing the roasting temperatures from 11$0^{\circ}C$ to 12$0^{\circ}C$, then decreased, while TBA values were increased continuously with increasing the roasting temperatures.

• Journal of Life Science
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• v.16 no.1
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• pp.37-43
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• 2006

Gap junction is an ion channel forming between adjacent cells. It also acts as a membrane channel like sodium or potassium channels in a single cell. The amino acid residues up to the $10^{th}$ position in the amino (N)-terminus of gap junction hemichannel affect gating polarity as well as current-voltage (I-V) relation. While wild-type Cx32 channel shows negative gating polarity and inwardly rectifying I-V relation, T8D channel in which threonine residue at $8^{th}$ position is replaced with negatively charged aspartate residue shows reverse gating polarity and linear I-V relation. It is still unclear whether these changes are resulted from the charge effect or the conformational change of the N-terminus. To clarify this issue, we made a mutant channel harboring cysteine residue at the $8^{th}$ position (T8C) and characterized its biophysical properties using substituted-cysteine accessibility method (SCAM). T8C channel shows negative gating polarity and inwardly rectifying I-V relation as wild-type channel does. This result indicates that the substitution of cysteine residue dose not perturb the original conformation of wild-type channel. To elucidate the charge effect two types of methaenthiosulfonate (MTS) reagents (negatively charged $MTSES^-$ and positively charged $MTSET^+$) were used. When $MTSES^-$ was applied, T8C channel behaved as T8D channel, showing positive gating polarity and linear I-V relation. This result indicates that the addition of a negative charge changes the biophysical properties of T8C channel. However, positively charged $MTSET^+$ maintained the main features of T8C channel as expected. It is likely that the addition of a charge by small MTS reagents does not distort the conformation of the N-terminus. Therefore, the opposite effects of $MTSES^-$ and $MTSETT^+$ on T8C channel suggest that the addition of a charge itself rather than the conformational change of the N-terminus changes gating polarity and I-V relation. Furthermore, the accessibility of MTS reagents to amino acid residues at the $8^{th}$ position supports the idea that the N-terminus of gap junction channel forms or lies in the aqueous pore.

• Journal of Life Science
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• v.18 no.4
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• pp.474-481
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• 2008

This research was performed to determine the proximate compositions, mineral contents, alginic acid, antioxidative activities and amino acids of sea tangles collected from Gijang and Wando area. Crude protein and ash contents were higher in Gijang sea tangle, whereas carbohydrate and moisture were higher in Wando in general. Mineral contents of Gijang sea tangle were higher than Wando. Especially, Na and K was the most abundant in both Gijang and Wando sea tangles. Alginic acid content was almost similar in both sea tangles. The major free amino acids were glutamic acid, aspartic acid, alanine, proline and hydroxyproline in both Gijang and Wando sea tangles. Antioxidative activity of methanol extract of sea tangle was measured by using DPPH radical scavenging and SOD-like activity. DPPH radical scavenging and SOD-like activity were about 17% ($40\;{\mu}g/ml$) and 7% ($5\;{\mu}g/ml$) higher, respectively, in Wando sea tangle. When stimulate the macrophages RAW264.7 cells with lipopolysaccharide (LPS), inhibition of NO synthesis of the methanol extract was 11% higher in Wando sea tangle comparing with Gijang samples.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.9
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• pp.1166-1171
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• 2006

This study was performed to investigate the effect of silk protein hydrolysates on blood glucose in diabetic mice (C57BL/KsJ db/db). The silk protein hydrolysates hydrolyzed by protease contains 87.52% of peptides of which molecular weight was below 2,000 dalton. The content of free amino acids was 14.80 g/100 g silk protein hydrolysates and major free amino acids were Pro, Thr, Arg and Ala. Silk protein hydrolysates were administered to the animals for 9 weeks at doses of 0.2, 0.5% and 0.8% solution. The body weight increase in the 0.5 and 0.8% fed groups were higher than control group. Food and water intake in the silk protein hydrolysates fed groups were lower than control group. The weight of liver was not different among groups, while the weight of kidney in control group was higher than silk protein hydrolysates fed groups. The blood glucose level in silk protein hydrolysates fed groups was lower than control group. In the glucose tolerance test, the blood glucose level in control group was the highest at 15 minutes after glucose injection while those in silk protein hydrolysates fed groups were the highest at 30 minutes. Results in this study suggest that silk protein hydrolysates show hypoglycemic effect in C57BL/KsJ db/db mice.

• Journal of Sericultural and Entomological Science
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• v.22 no.1
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• pp.26-45
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• 1980

Silk protein is synthesized in the silkgland of silkworm, Bombyx mori L. It is evident that silk productivity is one of the high heritable characters from the genetical aspects. It is also changed with the environmental circumstances. With this regard, this paper dealt with the varietal patterns of silkgland development and the factors concerning to the silk productivity of silkgland of silkworm by the synthesis of nucleic acids, profiles of amino acids and histological basis, using the eight parent silkworm varieties and their F$_1$ hybrids. 1. The weight of silkgland per larva increased proportionally in the F$_1$ hybrids which were crossed between longer silk yielding varieties. The silk content to the weight of the silkgland was higher in the longer silk yielding varieties than that in the shorter silk yielding varieties. 2. It was observed that the morphological changes of nuclei took place in the posterior silkgland cells with the larval development of the 5th instar. In varietal aspect, Jam 107 and Jam 108, longer silk yielding varieties, showed more branches in nuclei than the $N_2$ and $C_{60}$ which were shorter yielding ones. 3. It was observed that there was a high correlation between RNA content per unit weight of silkgland on the 6th day stage of 5th instar and silk productivity both in the parents and their F$_1$ hybrids. 4. RNA and DNA synthesis brought about thirty percent increase in the posterior silkgland of the longer silk yielding varieties during the 2nd day to the 4th day stages of the 5th instar, when compared with those in the posterior silkgland of the shorter silk yielding varieties. 5. RNA/DNA ratio in the posterior silkgland on the 2nd day and 4th day stages of the 5th instar was more increased in the longer silk yielding varieties than the shorter silk yielding varieties. 6. It was shown that DNA content for the longer silk yielding varieties came to be 374$\mu\textrm{g}$ per larva in the posterior division of silkgland on the 4th day stage of 5th instar, whereas it was 199$\mu\textrm{g}$ per larva for the shorter silk yielding varieties. 7 There was 34.8％ Alanine, 22.8％ Glycine, 9.1％ Serine and 7.3％ Tyrosine in the posterior division of silkgland as major amino acids. It is noticed that there was a little differences between the amino acids composition of posterior silkgland and silk fibroin. 8. There was some differences in the amino acids composition of posterior silkgland between pure lines and their hybrids. Glycine, Serine and acidic amino acids, essential to silk formation, seemed to be increased in the F$_1$ hybrids, whereas other amino acids such as Valine, Iso-leucine, Leucine, Lysine. Phenylalanine, Histidine and Arginine were reduced. 9. The content of Glycine, Alanine and Serine in the posterior division of silkgland was elevated in the longer silk yielding varieties than the others. Consequently. these three amino acids in the posterior silkgland seemed to be related to the silk yielding ability in the longer silk yielding varieties.s.

• Journal of Life Science
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• v.32 no.10
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• pp.784-791
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• 2022

This study observed changes in the body composition of Protaetia brevitarsis sinulensis larvae when reared with feed that included noni and nipa palm. Compared to the control group, the death rate and product yield of the treatment group were improved after the larval fasting process. The brightness of the larval powder of the treatment group increased, but the redness decreased. The crude fat content of the treated group was slightly increased according to the assays of the general components, but the mineral content was significantly increased. The total structural amino acids of the treatment group decreased, but the total free amino acids increased. The structural amino acids generally tended to decrease in the treatment group. However, the free amino acids showed no specific differences. Among the free amino acids, tryptophan, phosphoserine, and methylhistidine were highly increased in the treatment group, whereas threonine, methionine, and asparagine showed the opposite results. Among the polyunsaturated fatty acids, eicosapentaenoic acid (C20:5n3) of omega-3 was increased in the treatment group, but the omega-6 series was decreased. Since minerals, total free amino acids, and omega-3 fatty acids in the treatment group were increased compared to the control group, we suggest that noni and nipa palm can potentially be applied to the production of functionally improved substances as additional sources of feed for Protaetia brevitarsis sinulensis larvae.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.6
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• pp.392-399
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• 2000

This study was carried out to investigate the physicochemical characteristics of corn silks. Pollination of corn silks was finished within three days after silking, and elongation of open pollinated corn silks was stopped, but unpollinated silks elongated until eight days after silking. Moisture contents of corn silks were about 92-94% at silking stage, but continuously decreased. these were about 70-75% at 30 days after silking. Chlorophyll b was higher than chlorophyll a in corn silks, and chlorophyll a/b ratios of four hybrids were high in this order : silage ＞ sweet ＞ super sweet ＞ waxy corn. Free sugars in corn silks were mainly fructose, glucose and maltose. Their composition rate was 55% of glucose, 42% of fructose and 4% of maltose. Water soluble solid (Brix %) contents of unpollinated corn silks were ranged from 13.7 to 16.8 Brix % and pollinated corn silks were from 12.6 to 13.7 Brix %. Phytic, oxalic, malic. shikimic, glutaric and acetic acid were detected on corn silks. Phytic, oxalic and glutaric acid were considered as a major organic acids in corn silks. Amino acids in corn silks were high in this order : waxy ＞ silage ＞ sweet ＞sweet corn. Serine, glycine and thereoine were contained more than 10%, and five amino acids such as aspartic, glutaric, arginine, alanine and proline were ranged about 5 to 8%. Methionine and cystine, amino acids containing sulfur were contained only small quantity as about 2.1% and 1.3%, respectively. Acetaldehyde, ethanol, acetone, DMS, isobutylaldehyde, cis-3-hexanol, 3-hexe-1-ol, acetate, trans-2-hexanol and pentanol were detected as the volatile components in corn silks, but acetaldehyde and DMS were major volitiles in silage corn silks, and acetaldehyde, ethanol and DMS were major volitiles in waxy corn silks. The length of corn silks was a positively correlated with organic acids (r=${0.556}^*$), and a negatively correlated with amino acids (r=${-0.514}^*$), respectively. Free sugars were positively correlated with all characteristics tested and significantly correlated with organic acid (r=TEX>${0.703}^{**}$), and flavonoids (r=TEX>${0.544}^*$). Chlorophyll was significantly correlated with flavonoid contents (r=TEX>${0.523}^*$). For this reason chlorophyll was evaluated as an indirect selection character for the high flavonoid containing varieties.

• Journal of Life Science
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• v.33 no.10
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• pp.828-834
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• 2023

The cDNA that encodes transmembrane protein 258 (Tmem258) was cloned from Gryllus bimaculatus and named GbTmem258. This protein comprises 80 amino acids, has no N-glycosylation site, and contains five potential phosphorylation sites at two serines, two threonines, and one tyrosine. The predicted molecular mass of GbTmem258 is 9.06 kDa, and its theoretical isoelectric point is 5.5. The tertiary structure of GbTmem258 was predicted using the available secondary structure information, which suggests the presence of alpha helices (52.5%), random coils (22.5%), extended strands (16.25%), and beta turns (8.75%). Homology analysis revealed that GbTmem258 exhibits high similarity at the amino-acid level to Tmem258 found in other species. The effect of starvation and refeeding on GbTmem258 mRNA expression was also examined in this study. It was found that GbTmem258 mRNA expression in the hindgut progressively increased throughout the starvation period, peaking at almost 1.5 times the control level after six days of starvation. However, refeeding for one to two days after the six-day starvation period restored GbTmem258 mRNA expression to the control level. In fat body, GbTmem258 mRNA expression was almost 3-fold higher during starvation compared to the control level. Refeeding for one to two days after the six-day fast resulted in a decline in the expression to about a 2.5-fold increase over the control level. Throughout the starving and refeeding periods, no other tissues showed any discernible alterations in GbTmem258 mRNA expression.

• Food Science and Preservation
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• v.30 no.6
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• pp.1012-1028
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• 2023

The findings of this study confirmed the alteration of β-glucosidase activity, nutritional constituents, isoflavones, antioxidant activities, and digestive enzyme inhibition activities in soybeans during solid-state fermentation times with mycelia of Tricholoma matsutake. After nine days, the highest activity level was observed for β-glucosidase (3.90 to 38.89 unit/g) and aglycones (163.03 to 1,074.28 ㎍/g). The sum of isoflavones showed a significant decrease (3,489.41 to 1,325.66 ㎍/g) along with glycosides (2,753.87 to 212.43 ㎍/g) for fermentation, while fatty acids showed a slight increase and amino acids showed a marked increase. Total phenolic and flavonoid contents showed a corresponding increase according to fermentation times (5.58 to 15.09 GAE mg/g; 0.36 to 1.58 RE mg/g). Antioxidant and enzyme inhibition activities also increased; in particular, the highest level of scavenging activities was observed for ABTS (up 60.13 to 82.08%), followed by DPPH (up 63.92% to 71.98%) and hydroxyl (up 36.01 to 52.02%) radicals. Of particular interest, α-glucosidase (6.69 to 83.49%) and pancreatic lipase inhibition (1.22 to 77.43%) showed a marked increase. These results demonstrated that fermentation of soybeans with the mycelia of T. matsutake enhanced the nutritional and functional constituents, and the biological activities of soybeans. Thus, this fermentation technology can be used to produce a novel functional materials from soybeans.