• Journal of Aquaculture
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• 제21권3호
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• pp.190-195
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• 2008

We investigated the changes in growth, digestive enzymes activities, nucleic acids contents and RNA/DNA ratio of flounder Paralichthys olivaceus larvae (C for Paracyclopina nana, A for Artemia, and M for Mix of C and A) for 14 to 28 DAH. Body length of flounder larvae showed the best in the C trial at 28 DAH. The change of nucleic acids contents showed faster in C and M trials than A trial. And RNA/DNA ratio showed the significantly faster changes in C trial than A trial. High metamorphosis rates were also observed in C and M trial. $\alpha$-amylase activities increased gradually up to 28 DAH in all trials. Total alkaline protease (TAP) activities of A trial showed the highest value to 9 mU/larvae at 26 DAH. But others trials showed lower to $5{\sim}6$ mU/larva than A trial. TAP:$\alpha$-amylase activity ratio did not significantly changed to $0.025{\sim}0.053$ in A trial during the experiments. But, C and M trials tended to gradually decrease from $0.078{\sim}0.083$ (initial) to $0.013{\sim}0.018$ (final). Therefore, it shown the ratio gradually decreased of TAP:$\alpha$-amylase activity, stability of TAP activity, and rapid change of nucleic acids in trials grown positively. Thus, because P. nana could continuously supply the optimal nutrients for flounder larvae, we suggested the supplement of the copepod to an efficient feed of the flounder larvae.

• Proceedings of the Ginseng society Conference
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• 고려인삼학회 1984년도 학술대회지
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• pp.257-275
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• 1984

Enzymatic browning is considered desirable in tea and tobacco processing but undesirable in many fruits processing at the present time. It is necessary to understand the nature of the enzyme, phenoloxidase, in order to control browning reactions, and extend its effects to formation of browning products as antioxidants in ginseng. Ginseng exhibits antioxidant activity when incorporated with turkey dark meat patties. The activity in red ginseng showed about two times stronger than white ginseng. One of the phenolic antioxidants from fresh, white and reprocessed white ginseng was identified as phenol 2.6 Bis(1.1 dimethyl ethyl) 4-methyl among several unknown compounds by GC/mass spectrometer. In red ginseng, no phenol 2.6 Bis (1.1 dimethyl ethyl) 4-methyl was detected, the compound may be polymerized by phenoloxidase and form some higher molecular compounds which may possess high antioxidant activity. Phenoloxidase isozymes in fresh Korean ginseng (panax ginseng C.A. Meyer) were extracted with phosphate buffer at pH 7.3. The isozymes were purified through ammonium sulfate fractionation, dialysis and chromatography on a DEAE-cellulose column. Two groups of phenoloxidase were shown to be present, one in the floating agglomerated group and the other in the precipitate. group from the 0.85 saturation ammonium sulfate. The DEAE-cellulose column chromatography, the phenoloxidase isozyme present in the precipitate appears as the first peak (I), and that in the agglomerate in the second peak (II). Isozyme I showed higher activity with catechin and catechal, and isozyme II showed higher activity with p-cresol. The isozyme showed two optimum pH activity one at pH 4.5 and the other at 8.5 with catechin as substrate. Korean ginseng phenoloxidase has high heat stability. When heated at $75^{\circ}C$ for 2 hours, its activity remained $90\%\;and\;80\%$ on phenoloxidase I and II respectively. Phenoloxidase I was most active on (+) catechin followed by p-cresal, catechol and epicatechin. Phenoloxidase II was most active on p-cresal followed by (+) catechin, catechol, p-coumanic acid and epicatechin. Sodium bisulfite, sodium cyanide, ascorbic acid glutachion in the oxidized form, sodium diethyl dithiocarbomate and ethylendiamine tetra acetate (EDTA) acted as inhibitors. Red ginseng color development was initiated by phenoloxidase and finished by a followed sun drying process. The antiaging activity of ginseng may be initiated by the antioxidant in the ginseng.

• Food Science and Preservation
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• 제19권5호
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• pp.757-766
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• 2012

The SSH100-10 bacterial strain, which exhibits strong antifungal (anti-mold and anti-yeast) activity, was isolated from traditional korean soysauce aged 100 years. The strain was identified as Bacillus velezensis based on Gram-staining, the biochemical properties and 16S rRNA gene sequence determination. B. velezensis SSH100-10 showed strong proteinase activity and NaCl tolerance, but did not produce enterotoxin. Two-antifungal compounds from B. velezensis SSH100-10 were purified using SPE, preparative HPLC, and reverse phase-HPLC. The purified antifungal compounds were identified as $C_{14}$ and $C_{15}$ iturin through MALDI-TOF-MS and amino acid composition analysis. The stability characteristics of the antifungal compounds after temperature, pH, and enzyme treatments suggested that B. velezensis SSH100-10 produced more than two antifungal compounds; pH-stable $C_{14}$ iturin A and $C_{15}$ iturin A, and unidentified pH-unstable compounds. The results suggested that B. velezensis SSH100-10 can be used in soybean fermentation as a starter. Moreover it has potential as a biopreservative in the food and feed industry and as a biocontrol agent in the field of agriculture.

• Journal of Microbiology and Biotechnology
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• 제24권4호
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• pp.489-496
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• 2014

High levels of extracellular xylanase activity (211.79 IU/mg) produced by Paenibacillus sp. NF1 were detected when it was submerged-cultured. After three consecutive purification steps using Octyl-Sepharose, Sephadex G75, and Q-Sepharose columns, a thermostable xylanase (XynNF) was purified to homogeneity and showed a molecular mass of 37 kDa according to SDS-PAGE. The specific activity of the purified XynNF was up to 3,081.05 IU/mg with a 14.55-fold purification. The activity of XynNF was stimulated by $Ca^{2+}$, $Ba^{2+}$, DTT, and ${\beta}$-mercaptoethanol, but was inhibited by $Fe^{2+}$, $Zn^{2+}$, $Fe^{2+}$, $Cu^{2+}$, SDS, and EDTA. The purified XynNF displayed a greater affinity for oat spelt xylan with the maximal enzymatic activity at $60^{\circ}C$ and pH 6.0. XynNF, which was shown to be cellulose-free, with high stability at high temperature ($70^{\circ}C-80^{\circ}C$) and low pH range (pH 4.0-7.0), is potentially valuable for various industrial applications. The enzyme hydrolyzed oat spelt xylan to yield mainly xylooligosaccharides (95.8%) of 2-4 degree of polymerization (DP2-4). Moreover, the majority of the xylooligosacharides (DP2-4) products was xylobiose (61.5%). The thermostable xylanase (XynNF) thus seems potentially usefull in the production of xylooligosaccharides.

• KSBB Journal
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• 제25권6호
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• pp.520-526
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• 2010

In this work we have investigated the production of catalase from Bacillus sp. strains, which were screened and identified from soil. These strains were cultivated in shaking flasks with tryptic soy broth (TSB) at $30^{\circ}C$ and 200 rpm. Effects of the temperature and pH on the stability of the native catalase and whole cell viability were studied in the temperature range of $25-60^{\circ}C$ and the pH range of 7-13. Korean natural zeolite was added to culture medium and mixed with microorganisms for 24 hours. The native catalase maintained its activity over $50^{\circ}C$. The enzyme acitiviy of the catalase from Bacillus flexus BKBChE-3 was highest among the Bacillus sp. strains studied. Bacillus flexus BKBChE-3 and immobilized Bacillus cells have survived under extreme conditions of over $50^{\circ}C$ and pH 12. 60 mL of 10.5 mM $H_2O_2$ solution were entirely removed within 1 hour with catalase produced from Bacillus sp. on the flask. When Bacillus cells were immobilized on Korean natural zeolite, colony forming unit of Bacillus flexus BKBChE-3 was increased and high efficiency of hydrogen peroxide removal was observed.

• Korean Journal of Food Science and Technology
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• 제16권2호
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• pp.211-217
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• 1984

To study affinity of proteolytic enzymes to soy proteins, the physicochemical and functional properties of enzymatically modified protein products, kinetic parameters and degree of hydrolysis were measured using trypsin, alcalase (serine type protease) and pronase. Bacterial alcalase and pronase showed much greater affinity to soy protein than animal intestinal trypsin. This effect was very significant when unheated soy isolate was used as a substrate. Specific activities of these enzymes decreased with the increment of substrate concentration (over 2.0%, w/v) when heat denatured soy protein was used as a substrate. However, the decrease in specific activity was negligible at substrate concentrations lower than 2.0%. Polyacrylamide gel electrophoretic results showed that the pattern of 2S protein band changed distinctly in alcalase hydrolysis as compared with those of trypsin and pronase. Protein solubilities of alcalase and pronase hydrolyzates increased by 25-30%, at their pI (pH 5.0) over the control. Virtually no change was observed in solubility by trypsin hydrolysis. Heat coagulability and calcium-tolerance of the protein increased by enzymatic hydrolysis. No clear tendency, however, was observed for emulsion properties, foam expansion and the amount of free -SH groups. The enzyme treatment considerably decreased foam stability.

• Korean Journal of Food Science and Technology
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• 제32권2호
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• pp.328-334
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• 2000

A study was conducted to investigate the effect of ACAMS(Autoclaved-cooled amylomaize VII) and ACNMS(Autoclaved-cooled normal maize starch) containing resistant starch(RS) on ASW (Australian wheat flour) rheology and noodle quality. The water absorption in farinograph increased with the addition of ACAMS and ACNMS, but the dough stability decreased with the addition. The ACNMS added flours showed the highest initial pasting temperature and the lowest peak viscosity in RVA. The addition of ACAMS and ACNMS were not effective on the weight and volume of cooked noodles during cooking time for 5 min. However, as the cooking time increased, noodle weight and volume were the highest in control(no RS added flour) and the lowest in ACNMS added flours. Noodle texture was evaluated using rheometer. The hardness of RS(ACAMS, ACNMS) added noodles was higher than that of control. Cohesiveness was significantly different between control and ACAMS added noodles, but the cohesiveness of ACNMS added noodles was similar to other noodles. The elasticity of ACNMS added noodles in sensory test was lower than that of control but the smoothness and overall acceptibility were higher.

• Journal of agriculture & life science
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• 제46권1호
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• pp.163-176
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• 2012

TTo increase productivity of a strong extracellular alkaline protease (BCAP), stable strains of Bacillus clausii I-52 carrying another copy of BCAP gene in the chromosome were developed. Integrative vector, pHPS9-fuBCAP carrying BCAP promoter, ribosome binding site, signal sequence and active protease gene was constructed and transferred into B. clausii I-52, and integration of the constructed plasmid into chromosome was identified by PCR. An investigation was carried out on BCAP production by B. clausii I-52 and transformant C5 showing the highest relative activity of alkaline protease using submerged fermentation. Maximum enzyme activity was produced when cells were grown under the submerged fermentation conditions at $37^{\circ}C$ for 48 h with an aeration rate of 1 vvm and agitation rate of 650 rpm in a optimized medium (soybean meal 2%, wheat flour 1%, sodium citrate 0.5%, $K_2HPO_4$ 0.4%, $Na_2HPO_4$ 0.1%, NaCl 0.4%, $MgSO_47H_2O$ 0.01%, $FeSO_47H_2O$ 0.05%, liquid maltose 2.5%, $Na_2CO_3$ 0.6%). A protease yield of approximately 134,670U/ml was achieved using an optimized media, which show an increase of approximately 1.6-fold compared to that of non-transformant (83,960 U/ml). When the stability of transformant C5 was examined, the integrated plasmid pHPS9-fuBCAP was detected in the transformant after cultivation for 8 days, suggesting that it maintained stably in the chromosomal DNA of transformant C5.

• Journal of dental hygiene science
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• 제19권2호
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• pp.133-140
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• 2019

Background: The light-emitting diode (LED) curing light used is presumed to be safe. However, the scientific basis for this is unclear, and the safety of LED curing light is still controversial. The purpose of this study was to investigate the effect of LED curing light irradiation according to the conditions applied for the polymerization of composite resins in dental clinic on the cell viability and inflammatory response in Raw264.7 macrophages and to confirm the stability of LED curing light. Methods: Cell viability and cell morphology of Raw264.7 macrophages treated with 100 ng/ml of lipopolysaccharide (LPS) or/and LED curing light with a wavelength of 440~490 nm for 20 seconds were confirmed by methylthiazolydiphenyl-tetrazolium bromide assay and microscopic observation. The production of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) was confirmed by NO assay and $PGE_2$ enzyme-linked immunosorbent assay kit. Expression of interleukin $(IL)-1{\beta}$ and tumor necrosis factor $(TNF)-{\alpha}$ in total RNA and protein was confirmed by reverse transcription polymerase chain reaction and Western blot analysis. Results: The LED curing light did not affect the viability and morphology of normal Raw264.7 cells but affected the cell viability and induced cytotoxicity in the inflammation-induced Raw264.7 cells by LPS. The irradiation of the LED curing light did not progress to the inflammatory state in the inflammation-induced Raw264.7 macrophage. However, LED curing light irradiation in normal Raw264.7 cells induced an increase in NO and $PGE_2$ production and mRNA and protein expression of $(IL)-1{\beta}$ and $(TNF)-{\alpha}$, indicating that it is possible to induce the inflammatory state. Conclusion: The irradiation of LED curing light in RAW264.7 macrophage may induce an excessive inflammatory reaction and damage oral tissues. Therefore, it is necessary to limit the long-term irradiation which is inappropriate when applying LED curing light in a dental clinic.

• Journal of Life Science
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• 제29권10호
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• pp.1126-1135
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• 2019

From a sample of bamboo byproduct, the protease-producing yeast strain CO-1 was newly isolated. Strain CO-1 is spherical to ovoid in shape and measures $3.1-4.0{\times}3.8-4.4{\mu}m$. For the growth of strain CO-1, the optimal temperature and initial pH were $30^{\circ}C$ and 4.0, respectively. The strain was able to grow in 0.0-15.0%(w/v) NaCl and 0.0-9.0%(v/v) ethanol. Based on a phylogenetic analysis of its 18S rDNA sequences, strain CO-1 was identified as Pichia anomala. The extracellular protease produced by P. anomala CO-1 was partially purified by ammonium sulfate precipitation, which resulted in a 14.6-fold purification and a yield of 7.2%. The molecular mass of the protease was recorded as approximately 30 kDa via zymogram. The protease activity reached its maximum when 1.0%(w/v) CMC was used as the carbon source, 1.0%(w/v) yeast extract was used as the nitrogen source, and 0.3%(w/v) $MnSO_4$ was used as the mineral source. The protease revealed the highest activity at pH 7.0 and $30^{\circ}C$. This enzyme maintained more than 75% of its stability at a pH range of 4.0-10.0. After heating at $65^{\circ}C$ for 1 hr, the neutral protease registered at 60% of its original activity. The protease production coincided with growth and attained a maximal level during the post-exponential phase.