• Journal of Life Science
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• v.5 no.1
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• pp.26-32
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• 1995

The antimutagenic effects of insoluble dietary fibers(IDF) extracted from some green-yellow vegetables(kale, carrot, spinach, broccoli and soybean sprout) and soybean by binding the carcinogens of MeIQ (2-amino-3,4- dimethyl-imidazo(4,5-f) quinoline) and Trp-P-2(3-amino-1-methyl-5H-pyrido[4,3-b] indole) in Salmonella tylhimirium TA100 and TA98 were studied. All of the insoluble dietary fiber samples which binded MeIQ exhibited high antimutagenic effects by removing the mutagen. Among the samples, IDFs from kale and soybean showed strong binding capacity fo the carcinogen and revealed about 90% of the antimutagenic activity. the IDF samples showed somewhat lower binding capacity to the Trp-p-2. The lignin which extracted from kale, soybean and carrot, and the cellulose strongly removed the mutagenicity of MeIQ by the binding. Among the samples, the level of lignin in kale revealed the highest(about 10%), and it seemed that the higher content of lignin in kale is one of the reasons to increase its antimutagenic effect.

• Korean Journal of Microbiology
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• v.39 no.1
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• pp.51-55
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• 2003

To develop environment-friendly biofertilizer solubilizing insoluble phosphates, a bacterium possessing a high ability to solubilize $Ca_{3}(PO_{4})_{2}$) was isolated from the rhizosphere of peas. On the basis of its morphological, cultural, physiological characteristics, and Vitek analysis, this bacterium was identified as Pantoea agglomerans. The optimal medium composition and cultural conditions for the solubilization of insoluble phosphate by P. agglomerans R-38 were 3% of glucose.0.1% of TEX>$NH_{4}NO_{3}$, 0.02% of $MgSO_{4}\cdot\7H_{2}O$, and 0.06% of $CaCl_{2}\cdot\2H_{2}O$ along with initial pH 7.5 at $30^{\circ}C$. The highest soluble phosphate production under optimum condition was 898 mg/L after 5 days of cultivation. The solubilization of insoluble phosphate was associated with a drop in the pH of the culture medium. The strain produced soluble phosphate to the culture broth with the concentrations of 698 mg/L against CaHPO$_4$, 912 mg/L against hydroxyapatite, 28 mg/L against $FePO_{4}\cdot\4H_{2}O$, and 19 mg/L against $AIPO_{4}$, respectively.

• Journal of Sericultural and Entomological Science
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• v.42 no.1
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• pp.48-57
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• 2000

This study was undertaken to figure out the effects of hydrolysis conditions on the solubility of insoluble sericin, molecular weight distribution and thermal characteristics of hydrolysates in enzymatic hydrolysis by Alcalase 2.5L. It was indicated that the optimum treatment temperature and pH for the insoluble sericin were 50$\^{C}$ and 11, respectively. When the insoluble sericin was hydrolyzed with a various treatment conditions, the solubility of all hydrolysates were represented above 85% at given conditions. As the enzyme concentration increased, the solubility increased roughly, but the solubility increasement ratio was less above 2% enzyme concentration. As the treatment time increased, the solubility was also increased. It was showed in the molecular weight distribution of hydrolysates treated various enzyme concentrations and treatment times that when enzyme concentrations were 0.5, 2, 3%, the peaks of the distribution curve were shifted to left side which meant low molecular weight and was distributed much quantity with shifted to be left side, but treatment time was 6 hr. the peak was shifted to right side. When enzyme concentration was 5% and treatment time was below 2 hr., the peaks were shifted to right side, but treatment time was above 4hr. the peak was shifted to left side. The number-average molecular weights were distributed from 300 to 800 and those were decreased when treatment time was up to 4 hr., but increased a little when treatment time was 6hr. It was showed in the DSC curves of hydrolysates treated with treatment time of 0.5, 1, 2, 4, 6 hr. fixed 1% o.w.s enzyme concentration and control that the endothermic peak was observed near at 200$\^{C}$. The denaturation peak of the hydrolysates depending on treatment times had a tendency to shift to higher temperature. But, when the treatment time was 6 hr., the peak was shifted to lower temperature comparing another hydrolysates.

• Korean journal of food and cookery science
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• v.11 no.1
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• pp.20-25
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• 1995

The effects of cooking on the dietary fiber content in rice, brown rice, yellow soybean and black soybean were investigated. The dietary fiber contents were analyzed by Prosky's method(AOAC method) after boiling, microwave heating and autoclaving of the sample. It was showed that the different cooking methods resulted in different effects on the insoluble dietary fiber contents. Except yellow soybean, cooking time had little effect on insoluble dietary fiber contets in the other samples. The contents of soluble dietary fiber were generally increased by cooking. Increased cooking time reduced the content of soluble dietary fiber in brown rice but increased in rice. However, no significant differences caused by cooking time were observed for soluble dietary fiber in black soybean. The effects of cooking method on the total dietary fiber contents were similar to those of insoluble dietary fiber. The reasons for this might be that the main fraction of total dietary fiber was insoluble forms and the content of total dietary fiber was calculated as the sum of insoluble and soluble dietary fiber content.

• Journal of Sericultural and Entomological Science
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• v.41 no.1
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• pp.48-53
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• 1999

The study was carried out to investigate the effects of hydrolysis conditions such as treatment times and concentrations on the solubility of insoluble sericin using the hydrochloric acid solution. When insoluble sericin was hydrolyzed by HCl solution, the solubility was increased with the higher treatment concentration. As the results of electrophoresis of sericin powder obtained by the HCl treatment, a distinguishable band was not confirmed. Average degree of polymerizations(A.D.P.) of sericin hydrolyzed by HCl solution were about 4.2~5.9 and average molecular weights(M.W.) were about 470~670. The longer hydrolysis time reduced the whiteness of sericin powder. As the results of amino acid analysis, the amino acid compositions of the sericin powder from HCl treatment were sililar to that of insoluble sericin, but Tyr. and Arg. were not detected in the powder obtained by HCl treatment. In DSC analysis, thermal deformation and pyrolysis peak located at near 220$^{\circ}C$ and 330$^{\circ}C$.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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• pp.1524-1528
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• 2004

In order to determine the extent of change in nitrogen fractions and in vitro ruminal degradability of forage protein during ensilage and the influence on nitrogen utilization by sheep, orchardgrass (Dactylis glomerata L.) and alfalfa (Medicago sativa L.) were ensiled in separate 120 L silos for 5, 21 and 56 days. With respect to nitrogen fractions, fraction 1 (buffer solution soluble nitrogen), fraction 2 (buffer solution insoluble nitrogen-neutral detergent insoluble nitrogen), fraction 3 (neutral detergent insoluble nitrogen-acid detergent insoluble nitrogen), and fraction 4 (acid detergent insoluble nitrogen) were determined. Fractions 1 and 2 accounted for more than 80% of total nitrogen in orchardgrass and 90% of that in alfalfa. The proportion of fraction 1 in orchardgrass increased from 33.0% at day 0 to 52.0% after day 56 of ensiling. In the case of alfalfa silage it was 41.7% and 62.9%, respectively. Seventy percent of this increase occurred within the first 5 days of ensiling. A similar change of in vitro ruminal degradability of total nitrogen was also observed in both forages. Nitrogen retention in sheep tended to decrease as the length of ensiling increased, with a significantly positive correlation between urinary nitrogen and fraction 1, and in vitro ruminal degradability of total nitrogen.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.34-39
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• 1996

We examined the effects of crude hemicellulose, alcohol-insoluble hemicellulose, high molecular weight soluble polysaccharide (HMS-P : MW>10 kDa) and low molecular weight souble polysaccharide (LMS-P : MW<10 kDa) fraction isolated from buckwheat (raw, roast and steam) on digestive enzyme activity in vitro. The enzyme activities were measured after the polysaccharides-enzyme mixtures were incubated at $37^{\circ}C$ for 5 min. Crude hemicellulose, alcohol-insoluble hemicellulose and residue lowered ${\alpha}-amylase$ activity, whereas HMS-P and LMS-P had no inhibitory effect. All polysaccharides except LMS-P lowered lipase activity. Crude hemicellulose, alcohol-insoluble hemicellulose, residue and HMS-P showed a marked decrease of trypsin and chymotrypsin activity but LMS-P showed a slight decrease of them.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.437-440
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• 2006

To explore the possible usefulness of ${\beta}$-glucans as natural antioxidants, the antioxidant profiles of ${\beta}$-glucan, extracted from Saccharomyces cerevisiae KCTC 7911, and water soluble and insoluble mutant ${\beta}$-glucan, isolated from yeast mutant S. cerevisiae IS2, were examined by five different in vitro evaluation methods: lipid peroxidation value (POV), nitric oxide (NO), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, reducing power, and ${\beta}$-carotene diffusion assay. The antioxidant activities of all ${\beta}$-glucans evaluated in POV test were comparable to or better than that of the known antioxidant, vitamin C. Remarkably, the ${\beta}$-glucan and water insoluble mutant ${\beta}$-glucan possessed 2.5-fold more potent activity than vitamin C at a dosage of 2 mg. Although vitamin C showed 100-fold greater activity than all ${\beta}$-glucans in NO and DPPH tests for measuring the radical scavenging capacity, all ${\beta}$-glucans revealed higher radical scavenging activity than the known radical scavenger, N-acetyl-L-cysteine (NAC), in DPPH test. The water insoluble mutant ${\beta}$-glucan had 2.6- and 5-fold greater antioxidative activity than water soluble ${\beta}$-glucan in NO and DPPH tests, respectively, showing that all ${\beta}$-glucans were able to scavenge radicals such as NO or DPPH. While all ${\beta}$-glucans revealed lower antioxidant profiles than vitamin C in both reducing power activity and ${\beta}$-carotene agar diffusion assay, the ${\beta}$-glucan and water insoluble mutant ${\beta}$-glucan did show a marginal reducing power activity as well as a considerable ${\beta}$-carotene agar diffusion activity. These results confirmed the potential usefulness of these ${\beta}$-glucans as natural antioxidants.

• Archives of Pharmacal Research
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• v.9 no.3
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• pp.157-161
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• 1986

Isolated calf thymus nuclei were in vitro methylated with S- adenosy-L-methyl-$^{14}C$ methionine, and the proteins were fractionated according to their solubilities. Histone fraction ($H_{2}SO_{4}$-soluble fraction) contained approximately 60% total radioactivity incorporated, while "residual protein" which was ($H_{2}SO_{4}$-insoluble contained the remaining radio-activity. The "residual protein" was further fractionated into various acidic proteins, which contained very littel of the radioactivity. However, the protein fraction eluted from DEAE-cellulose with 0.5 N NaOH contained the largest amount of radioactivity. This protein was found to be basic in nature by amino analysis.

• Journal of Sericultural and Entomological Science
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• v.33 no.1
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• pp.1-5
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• 1991

PBS soluble- and insoluble-extracts form silkworm eggs were analysed by native-PAGE and SDS-PAGE. During the embroyonic development, soluble proteins which are mainly composed of ESP, vitellin and 30K proteins showed similar degradation pattern in both electrophoretic analyses. Several peptides which seemed to be intermediated forms of yolk proteins were detected in latter part of embryogenesis, while a protein band newly appeared in one day elapsed after acid treatment. When insoluble extracts from silkworm eggs were analysed with SDS-PAGE, several peptides were detected at the later stages of the embryonic development, and newly hatched larvae. These peptides are considered to be structure proteins for embryonic morphogenesis.