• Applied Biological Chemistry
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• v.19 no.4
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• pp.219-226
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• 1976

To meet the need of protein feed and fine more efficient ways of returning waste to resources, we have carried out the study of the production of yeast for foods and feeds from the corn starch cake. The present study includes the method for acid-hydrolysis, the selection of yeast capable of utilizing hydrolyzate of the corn starch cake, and culture condition of Candida tropicalis under the liquid culture and the semisolid culture. Obtained results were as follows. 1. Hydrochloric acid was more excellent on the hydrolysis of the corn starch cake than sulfuric acid, and the yield of sugar was maximum, 57.2%, when the corn starch cake was hydrolyzed with 1.0% of hydrochloric acid at 2.0kg/cm for 30 minutes. 2. As the acid solution content was increased, more sugar was liberatedfrom the mixture, until the acid solution-substrate ratio reached 10:1. Beyond this point, no further increase was observed. To prepare the cultural medium of semisolid fermentation, a acid solution to substrate ratio of 3:1 appeared to be optimum. 3. Out of 6 yeast strains, Candida tropicalis had excellent growth on the hydrolyzate of the corn starch cake, and optimum temperature and initial pH were $30^{\circ}C$ and 6.0 respectively. 4. Optimum liquid medium of Candida tropicalis is ures 0.3%, potassium phosphate monobasic 0.15g and magnesium sulfate 0.04g in 100ml of the hydrolyzate of the corn starch cake, while optimum semisolid medium is ammonium chloride 0.4g, potassium phosphate monobasic 0.1%, magnesium sulfate 0.04%. 5. Candida tropicalis could assimilate the sugar in the hydrolyzate up to more than 88.75%, and a yield of dry yeast reached 19.13% to the corn starch cake under the liquid culture. 6. Compared to the that of the untreated corn starch cake, the cellulose content of the semisolid fermented cake decreased by 3.76% to 14.7%, whereas dry yeast contents increased by 13.89%.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.251-258
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• 2004

Soil testing for silicon (Si) in the upland soils has not been sufficiently investigated. The objective of this study was to identify a suitable Si extraction method for upland soils of oriental melon (Cucumis melo L.). Thirty-eight surface soil samples and matured leaf samples were collected from plastic film houses in Sungju, Gyeongbuk province. In the laboratory, six different methods were used for extracting Si from the soils. The methods included 0.5 N HCl extraction, 1 N sodium acetate buffer (PH 4.0) extraction, citric acid 1% extraction, water extraction, Tiis buffer pH 7.0 extraction, and extraction after incubation with water for 1 week. The concentration of dissolved Si in soil extracts from all methods was determined colorimetrically. With 1 N sodium acetate buffer extraction, as the available soil Si increased, the concentration ofSi in oriental melon leaf increased until around $14g\;SiO_2\;kg^{-1}$ was reached in the form of a saturation curve. Also, among the methods studied, extraction with 1 N sodium acetate buffer was the only method provided a significant linear correlation with oriental melon leaf Si content in the range of extractable soil Si lower than the level which inducing Si saturation in oriental melon leaf. These results indicate that 1 N sodium acetate buffer extraction procedure is the best soil Si test method for upland soils of oriental melon. This sodium acetate buffer extraction procedure is rapid and quite well acquainted with scientists and farmers, since the method has been used for routine paddy soil testing.

• Korean Journal of Environmental Agriculture
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• v.23 no.2
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• pp.92-98
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• 2004

The adsorption and desorption of Pb, Cd, Co, Zn, Cr, Co, Ni, and Mo on the waste Undaria sp. were studied. Except for Pb. the mono adsorption rate for all heavy metals were lower than that of the heavy metals mixed. However, the adsorption capacity of the heavy metals by 1g of biosorption, in mixed heavy metals increased According to FT-IR analysis of the biosorbent after heavy metal biosorption, the replacement of the functional group by the heavy metals ions could be confirmed and the inverted peaks became larger after heavy metals adsorption. The adsorption equilibrium of heavy metals was reached in about 1 hour. The equilibrium parameters were determined based on Langmuir and Freundlich isotherms. The affinity of metals on the biosorbent decreased in the following order: Pb>Cu>Cr>Cd>Co. The desorption rate decreased in the following sequence: NTA>$H_2SO_4$>HCl>EDTA. The desorption rate of heavy metals by NTA increased with increase in the concentration from 0.1 to 0.3% but the desorption rate became constant beyond 0.3%. Therefore, it represented that desorption rate of heavy metals was suitable under optimized condition ($30^{\circ}C$, pH 2 and 0.3% NTA solution) and was fast with 80% or more the uptake occurring within 10 min of contact time.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.480-485
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• 2019

The present study was conducted to compare antioxidant capacities of protein hydrolysates from four different edible insects (Protaetia brevitarsis larvae, Allomyrina dichotoma larvae, Gryllus bimaculatus imago, and Tenebrio molitor larvae) which have recently been registered as food varieties in Korea. Protein hydrolysates were prepared from each insect using enzymatic hydrolysis using alcalase, and were then separated into a fraction containing ${\leq}3kDa$. According to $RC_{50}$ values and trolox equivalent antioxidant capacity results obtained from five different antioxidant analyses, the Gryllus bimaculatus (GB) hydrolysate showed relatively high levels of antioxidant capacity and, in particular, the GB hydrolysate showed considerably strong antioxidant activities in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and in ferric reducing antioxidant power (FRAP) assays. The GB hydrolysate also showed the strongest inhibitory effect on peroxidation of linoleic acid, and its rate of inhibition at $100{\mu}g/mL$ on day 3 of treatment was 60.26%. These results suggest that protein hydrolysates from edible insects including GB represent potential sources of natural antioxidants.

• Clinical and Experimental Pediatrics
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• v.49 no.7
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• pp.784-789
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• 2006

Purpose : $Henoch-Sch{\ddot{o}}nlein$ purpura(HSP) is a systemic vasculitis involving small vessels of skin, gastrointestinal(GI) tract and kidney. Digestive involvement of HSP can be serious with massive GI bleeding, perforation, and intussusception. However, some patients do not respond to conventional corticosteroid therapy. In this study, we investigated the efficacy of intravenous immunoglobulin (IVIG) for serious digestive manifestations not responding to steroid. Methods : From April 1999 to January 2005, 22 children diagnosed as HSP with severe GI symptoms were included. Initially, all patients were treated with intravenous methylprednisolone. IVIG 2 g/kg of body weight was infused in children refractory to steroid therapy. Clinical data were reviewed retrospectively. Results : Among 22 children, 12 children underwent IVIG therapy. The mean duration of corticosteroid therapy was $5.61{\pm}4.9$ days before IVIG therapy, and 11 of 12 patients experienced disappearance of GI manifestations after the initiation of IVIG infusion. In one patient, IVIG was ineffective in relieving abdominal pain, but melena subsided. Comparison of the duration of hospitalization between IVIG group and corticosteroid group revealed no significant difference($12.8{\pm}7.6$ days vs. $13.2{\pm}7.8$ days, P=0.777). But, the total duration of abdominal pain decreased in IVIG group although the difference between two groups was not significant($8.8{\pm}8.1$ days vs. $14.8{\pm}16.9$ days, P=0.306). Among 10 children treated with steroid only, 2 children were operated for bowel perforation and intussusception. In contrast, there was no perforation in 12 children who underwent IVIG therapy. Conclusion : IVIG could be the alternative therapy to corticosteroids in children with severe digestive manifestations of HSP.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1142-1149
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• 2004

Streptococcus mutans has the capacity of inducing dental caries. Thus, to develop a novel way of preventing dental caries, a cell wall hydrolase-producing strain was isolated and its characteristics were investigated. Among 200 alkalophilic strains isolated from soil, 8 strains exhibited lytic activities against Streptococcus mutans. However, strain YU5215 with the highest cell wall hydrolase activity was selected for further study. Strain YU5215 was identified as a novel strain of Bacillus based on analyzing its 16S rDNA sequence and Bergey's Manual of Systematic Bacteriology, and thus designated as Bacillus mutanolyticus YU5215. The optimal conditions for the production of the cell wall hydrolase from Bacillus mutanolyticus YU5215 consisted of glucose ($0.8\%$), yeast extract ($1.2\%$), polypeptone ($0.5\%$), $K_{2}HPO_{4}\;(0.1\%$), $MgSO_{4}{\cdot}7H_{2}O$ ($0.02\%$), and $Na_{2}CO_{3}\;(1.0\%$) at pH 10.0. Bacillus mutanolyticus YU5215 was cultured at 30^{circ}C for 72 h to produce the cell wall hydrolase, which was then purified by acetone precipitation and CM-agarose column chromatography. The molecular weight of the lytic enzyme was determined as 22,700 Da by SDS-PAGE. When the cell wall peptidoglycan of Streptococcus mutans was digested with the lytic enzyme, no increase in the reducing sugars was observed, while the free amino acids increased, indicating that the lytic enzyme had an endopeptidase-like property. The amino terminus of the cell wall peptidoglycan digested by the lytic enzyme was determined as a glutamic acid, while the lytic site of the lytic enzyme in the Streptococcus mutans peptidoglycan was identified as the peptide linkage of L-Ala and D-Glu.

• The Korean Journal of Pharmacology
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• v.22 no.1 s.38
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• pp.51-59
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• 1986

The effect of metabolic substrate fructose on the force of contraction of isolated rat atria depressed with lidocaine was determined. Fructose produced dose-dependent increase in the force of contraction of isolated atria depressed by substrate-free Krebs-Ringer bicarbonate medium. The maximally effective concentration of fructose was 30 mM. The isolated atria, suspended in Krebs-Ringer bicarbonate glucose medium aerated with 95% $O_2-5%CO_2$at $30^{\circ}C$ and pH 7.4, were depressed 50% by approximately 2.34 mg/100 ml of lidocaine. Addition of 30 mM fructose to these depressed atria resulted in a marked increase in the contractile force similar to that with pyruvate and acetate. Fructose had no significant effect, however, on atria exposed to low-calcium medium. The results are consistent with a previous report suggesting blockade by lidocaine of the uptake or utilization of glucose in the glycolytic pathway, and further pinpoint the blockade as an early step in the glycolytic sequence prior to the phospho-fructokinase step.

• Biomolecules & Therapeutics
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• v.22 no.5
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• pp.445-452
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• 2014

The purpose of this study was to investigate the therapeutic effects of DA-9801, an optimized extract of Dioscorea species, on diabetic peripheral neuropathy in a type 2 diabetic animal model. In this study, db/db mice were treated with DA-9801 (30 and 100 mg/kg, daily, p.o.) for 12 weeks. DA-9801 reduced the blood glucose levels and increased the withdrawal latencies in hot plate tests. Moreover, it prevented nerve damage based on increased nerve conduction velocity and ultrastructural changes. Decrease of nerve growth factor (NGF) may have a detrimental effect on diabetic neuropathy. We previously reported NGF regulatory properties of the Dioscorea genus. In this study, DA-9801 induced NGF production in rat primary astrocytes. In addition, it increased NGF levels in the sciatic nerve and the plasma of type 2 diabetic animals. DA-9801 also increased neurite outgrowth and mRNA expression of Tieg1/Klf10, an NGF target gene, in PC12 cells. These results demonstrated the attenuation of diabetic peripheral neuropathy by oral treatment with DA-9801 via NGF regulation. DA-9801 is currently being evaluated in a phase II clinical study.

• Nuclear Engineering and Technology
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• v.46 no.6
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• pp.847-856
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• 2014

Spent resin waste containing a high concentration of $^{14}C$ radionuclide cannot be disposed of directly. A fundamental study on selective $^{14}C$ stripping, especially from the IRN-150 mixed bed resin, was carried out. In single ion-exchange equilibrium isotherm experiments, the ion adsorption capacity of the fresh resin for non-radioactive $HCO_3{^-}$ ion, as the chemical form of $^{14}C$, was evaluated as 11mg-C/g-resin. Adsorption affinity of anions to the resin was derived in order of $NO_3{^-}$ > $HCO_3{^-}{\geq}H_2PO_4{^-}$. Thus the competitive adsorption affinity of $NO_3{^-}$ ion in binary systems appeared far higher than that of $HCO_3{^-}$ or $H_2PO_4{^-}$, and the selective desorption of $HCO_3{^-}$ from the resin was very effective. On one hand, the affinity of $Co^{2+}$ and $Cs^+$ for the resin remained relatively higher than that of other cations in the same stripping solution. Desorption of $Cs^+$ was minimized when the summation of the metal ions in the spent resin and the other cations in solution was near saturation and the pH value was maintained above 4.5. Among the various solutions tested, from the view-point of the simple second waste process, $NH_4H_2PO_4$ solution was preferable for the stripping of $^{14}C$ from the spent resin.

• Journal of Physiology & Pathology in Korean Medicine
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• v.32 no.6
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• pp.375-383
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• 2018

This study was conducted to investigate the cognitive improvement and memory recovery effects of Korean and Chinese Crataegus pinnatifida ethanolic extracts on scopolamine-induced memory impairment in mice. In vivo studies were carried out with mice treated with Korean Crataegus pinnatifida extracts (KCF) and Chinese Crataegus pinnatifida extracts (CCF) in doses of 5 and 50 mg/kg (p.o.) and scopolamine was injected 30 min before the behavioral testing. Antioxidant activity was assessed by 2,2-diphenyl-1-picryl hydrazyl (DPPH) assay and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay, and acetylcholinesterase inhibition by Ellman's modified method. The chlorogenic acid and hyperoside as marker compounds of KCF and CCF was quantified by ultra-performance liquid chromatography analysis (UPLC). Results showed that KCF was more contained high content of chlorogenic acid and hyperoside than CCF. In addition, KCF was more exerted free radical (DPPH and ABTS) scavenging activity and blocked AChE activity than CCF. In vivo studies also showed that KCF administration has a further improved the memory of scopolamine-treated mice than CCF in Y-maze test, passive avoidance test and Morris water maze test. These results revealed that KCF more prevents scopolamine-induced memory impairments through antioxidant and acethylcholinesterase inhibition effect compared CCF.