• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.3
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• pp.284-288
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• 2005

Baker's yeast was disrupted in a 1.4-L stainless steel horizontal bead mill under a continuous recycle mode using 0.3 mm diameter zirconia beads as abrasive. A single pass in continuous mode bead mill operation liberates half of the maximally released protein. The maximum total protein release can only be achieved after passaging the cells 5 times through the disruption chamber. The degree of cell disruption was increased with the increase in feeding rate, but the total protein release was highest at the middle range of feeding rate (45 L/h). The total protein release was increased with an increase in biomass concentration from 10 to $50\%$(w/v). However, higher heat dissipation as a result of high viscosity of concentrated biomass led to the denaturation of labile protein such as glucose 6-phosphate dehydrogenase (G6PDH). As a result the highest specific activity of G6PDH was achieved at biomass concentration of $20\%$(ww/v). Generally, the degree of cell disruption and total protein released were increased with an increase in impeller tip speed, but the specific activity of G6PDH was decreased substantially at higher impeller tip speed (14 m/s). Both the degree of cell disruption and total protein release increased, as the bead loading increased from 75 to $85\% (v/v)$. Hence, in order to obtain a higher yield of labile protein such as G6PDH, the yeast cell should not be disrupted at biomass concentration and impeller tip speed higher than $20\%(w/v)$ and 10 m/s, respectively.

• Biomolecules & Therapeutics
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• v.17 no.3
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• pp.241-248
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• 2009

The purpose of this study was to evaluate the effect of methylsulfonylmethane (MSM) on hair growth promotion of magnesium ascorbyl phosphate (MAP) for the treatment of alopecia. Aqueous solutions of MAP 7.5% with or without MSM 1%, 5% or 10% were prepared and applied onto the depilated back skin of the male mice once a day for 20 days. The degree of hair growth was evaluated by visual scoring using hair growth quantification scale (0-5, 0 being initial state and 5 being complete hair growth). In vitro transdermal penetration and intradermal retention studies of MAP were performed with Franz diffusion cell using hairless mice skin. Hair growth in the group treated with the aqueous solution containing MAP 7.5% and MSM 10% was comparable to or better than the result in the group treated with minoxidil 5% solution. Hair growth promotion of MAP was dose-dependently increased by the presence of MSM used in combination with MAP 7.5% solution. The in vitro transdermal penetration of the MAP was decreased in proportion to the concentration of MSM. However, intradermal retention of MAP was profoundly and dose-proportionally increased as a function of MSM concentration, reaching 802 ${\mu}g/cm^2$ in the presence of MSM 10% (200-fold increase). The effect of MSM on hair growth promotion of MAP was dose-proportional to the concentration of MSM due to the enhanced intradermal retention of MAP in the presence of MSM. Therefore, topical application of MAP together with MSM appears to be useful for the treatment of alopecia.

• Journal of Periodontal and Implant Science
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• v.46 no.5
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• pp.350-359
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• 2016

Purpose: The purpose of the present study was to evaluate the effectiveness of a minimal concentration of bone morphogenetic protein-2 (BMP-2) in terms of quantitative and qualitative analyses of newly formed bone in a rabbit maxillary sinus model. Methods: In 7 rabbits, sinus windows were prepared bilaterally. Biphasic calcium phosphate (BCP) loaded with 0.05 mg/mL BMP-2 was grafted into one sinus (the BMP group) and saline-soaked BCP was placed into the other (the control group) in each animal. The animals were allowed an 8-week healing period before being sacrificed. Specimens including the augmented area and surrounding tissues were then removed and evaluated both radiographically and histologically. Results: There was a difference in the mineralization of new bone between the groups. In the BMP group, the greater part of the new bone consisted of mature lamellar bone with an evident trabecular pattern, whereas the control group showed mostly woven bone, consisting only partially of lamellar bone. Histometrically, the area of new bone was significantly greater ($4.55{\pm}1.35mm^2$ vs. $2.99{\pm}0.86mm^2$) in the BMP group than in the control group (P<0.05); however, the total augmentation volumes were not significantly different between the groups. Conclusions: Within the limitations of this study, it can be suggested that a minimal concentration of BMP-2 (0.05 mg/mL) had an osteoinductive effect with accelerated mineralization in a rabbit sinus model using a BCP carrier.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.338-344
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• 1998

New type of chitosan derivatives, chitosan-g-MAP, were synthesized by graft copolymerization of mono (2-methacryloyl oxyethyl) acid phosphate (MAP) into chitosan, in order to solubilize chitosan in water. Ceric ammonium nitrate was used as an initiator for graft copolymerization. The optimal conditions for graft copolymerization were determined on the basis of reaction temperature, time, and the concentration of initiator and monomer. The reaction conditions for the highest percentage of grafting were as follows: an initiator concentration, 3.5${\times}$10$\^$-3/ M; monomer concentration, 0.19 M; and reaction temperature, 40$^{\circ}C$ The reaction rate reached the maximum value after 4 hrs of reaction. Antifungal activity was tested against Candida albicans, Trichophyton rubrum and Trichophyton violaceum by using chitosan-g-MAP and two other chitosan samples which have degree of deacetylation of 70% (DA-7) and 90% (DA-90). Their antifungal activities were investigated in weak acidic range. Maximum antifungal activity of them was observed at pH 5.75. Chitosan-g-MAP inhibited thoroughly the growth of Candida albicans and Trichophyton violaceum. Howerver, DA-70 and DA-90 showed higher antifungal activities on Trichophyton rubrum than that of chitosan-g-MAP.

• Environmental Analysis Health and Toxicology
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• v.13 no.3_4
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• pp.133-142
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• 1998

Effects of phosphorous (P) and methylglyoxal (MG) on the cell number, dry weight, chlorophyll content, photosynthetic and respiratory rate, phosphate uptake and protein content of green algae (Scenedesrnus obliquus) were studied. The algal cell number from the medium treated with 0.5-1.0 mM of MG at 1/2 P or 1/4 P concentration was significantly lower than those of algae treated :with full strength of phosphrous in medium. The inhibitory effect of MG on algal cell division was enhenced at low concentration of phosphorous in medium. At the beginning of logrithmic phase of algal growth, the mean dry weight of algae from the medium without MG-treatment in 1/2 P media was significantly higher than that of algae treated with MG. After logrithmic phase of growth cycle, the mean dry weight of algae from the medium with 1.0 mM of MG-treatment in 1/4 P media was significantly lower than that of algae treated with or without MG. At logrithmic phase of algal growth, there were significant differences in the chlorophyll content among all groups of tested algae with various concentrations of P and MG. At 15 days after inoculation, the mean chlorophyll content per algal cell from the media without MG-treatment in 1/2P was significantly higher than that of other cells from MG-treated media. The adverse effect of MG at concentration of 0.5-1.0mM in 1/2 and 1/4 P media on photosynthetic rate was observed. The mean photosynthetic rate of algal cell without P and MG treatment at 15 days after inoculation was significantly higher than that of MGtreated algae. After logarithmic phase, the algal cell treated with 0.5mM of MG with full strength of phosphorous showed significantly high respiratory rate than that of other cell groups. There were significant differences in mean phosphate uptake rate among all groups of Scenedesmus obliquus at logarithmic phase. At 12 days after inoculation, phosphate uptake rate per each algal cell from the basic media without MG and P treatment was rapidly reduced which shows early introduction to stationary phase.

• Environmental Engineering Research
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• v.21 no.1
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• pp.15-21
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• 2016

Magnesium potassium phosphate cement (MKPC) is an effective agent for solidification/stabilization (S/S) technology. To further explore the mechanism of the S/S by MKPC, two kinds of Cd including $Cd(NO_3)_2$ solution (L-Cd) and municipal solid waste incineration fly ash (MSWI FA) adsorbed Cd (S-Cd), were used to compare the effects of the form of heavy metal on S/S. The results showed that all the MKPC pastes had a high unconfined compressive strength (UCS) above 11 MPa. For L-Cd pastes, Cd leaching concentration increased with the increase of Cd content, and decreased with the increase of curing time. With the percentage of MSWI FA below 20%, S-Cd pastes exhibited similar Cd leaching concentrations as those of L-Cd pastes, while when the content of MSWI FA come up to 30%, the Cd leaching concentration increased significantly. To meet the standard GB5085.3-2007, the highest addition of S-Cd was 30% MSWI FA (6% Cd contained), with the Cd leaching concentration of 0.817 mg/L. The S/S of L-Cd is mainly due to chemical fixation, and the hydration compound of Cd was $NaCdPO_4$, while the S/S of S-Cd is due to physical encapsulation, which is dependent on the pore/crack size and porosity of the MKPC pastes.

• Microbiology and Biotechnology Letters
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• v.16 no.5
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• pp.402-406
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• 1988

The aim of the presented paper was to elucidate the physiological background of ethanol inhibition on glucose uptake, ethanol production and cell growth in Z. mobilis. Data obtained from batch and continuous cultures showed that the rates of glucose uptake and ethanol production were not affected but growth rate was apparently reduced by ethanol produced. In order to know the effects of ethanol on the anabolism and the catabolism in Z. mobilis, enzyme activities of the Enter-Doudoroff pathway, viz. hexokinase, glucose 6-phosphate dehydrogenase, were analyzed with the cell grown at different concentration of ethanol produced. As results, it was found that the activities of the glucose kinase and the glucose 6-phosphate dehydrogenase were not affected greatly by the concentration of ethanol where the glucose uptake rates revealed a relatively constant value. However it was very interesting to note that transketolase, which is an essential enzyme to provide the important precursors for cell growth, was affected more apparently to reduce by increasing ethanol levels. Those results might suggest that the apparent reduction of growth rate at ethanol concentration above 20 g/$\ell$ would be caused by the reduction of the transketolase activity, which in turn provide less precursor for the cell growth.

• Korean Journal of Microbiology
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• v.32 no.3
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• pp.222-231
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• 1994

Kinetic analysis was done to elucidate the reaction mechanism of purine nucleoside phosphorylase (PNP) in Saccharomyces cerevisiae. The binary complexes of PNP${\cdot}$phosphate and PNP${\cdot}$ribose 1-phosphate were involved in the reaction mechanism. The initial velocity and product inhibition studies demonstrated were consistent with the predominant mechanism of the reaction being an ordered bi, bi reaction. The phosphate bound to the enzyme first, followed by nucleoside and base were the first product to leave, followed by ribose 1-phosphate. The kinetically suggested mechanism of PNP in S. cerevisiae was in agreement with the results of protection studies against the inactivation of the enzyme by sulfhydryl reagents, p-chloromercuribenzoate (PCMB) and 5,5'-dithiobisnitrobenzoate (DTNB). PNP was protected by ribose 1-phosphate and phosphate, but not by nucleoside or base, supporting the reaction order of ordered bi, bi mechanism. PCMB or DTNB-inactivated PNP was totally reactivated by dithiothreitol (DTT) and the activity was returned to the level of 77% by 2-mercaptoethanol, indicating that inactivation was reversible. The kinetic behavior of the PCMB-inactivated enzyme had been changed with higher $K_m$ value of inosine and lower $V_m$, and was restored by DTT. Inactivation of enzyme by DTNB showed similar pattern of K sub(m) value with that by PCMB, but had not changed the $V_m$ value, significantly. Negative cooperativity was not found with PCMB or DTNB treated PNP at high concentration of phosphate.

• YAKHAK HOEJI
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• v.38 no.1
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• pp.57-66
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• 1994

We studied the effect of eicosanoids on the content of energy metabolites and the intrasynaptosomal $Ca^{++}([Ca^{++}]_i)$ concentration in cerebral ischemic rats. An ischemic model was made by bilateral carotid artery ligation (BCAL) and by incubation of synaptosomes under aglycemic and $N_2$ gas bubbling condition. The content of ATP, creatine phosphate and glucose decreased at 15 minutes after BCAL while that of lactate increased in male Wistar rats. Oral administration of EPA(100 mg/ml/Kg/day) or DHA(16 mg/ml/Kg/day) for 6 weeks improved both the decreases and the increase of the cerebral energy metabolites. In addition, the increase of $[Ca^{++}]_i$, under BACL was suppressed by EPA or DHA treatment. When the both Wistar rats and SHR were administered orally with EPA or DHA for 6 weeks, the effect on the increase of $[Ca^{++}]_i$ under ischemia by $N_2$ gas bubbling were protected. From these results, it may be that EPA or DHA treatment were greatly contributed to preservation of ischemic cerebral energy metabolism and $Ca^{++}$ concentration.

• Korean Journal of Medicinal Crop Science
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• v.21 no.4
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• pp.262-267
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• 2013

The purpose of this study was to research for anti-oxidation and anti-wrinkle effects of Acar mono Sap (AM). To cosmetic effect of AM, safety effect (MTT assay), anti-wrinkle effect (elastase, MMP-1 inhibition assay) and anti-oxidant effect (DPPH assay) were measured. When water extract of AM was used for cell viability, it was over 100% at 6% (6 ml/100 ml in phosphate buffer) concentration. AM showed 45.7% elastase inhibition and 23.7% MMP-1 inhibition at 50% (50 ml/100 ml in phosphate buffer) concentration so that it had good anti-wrinkle characteristic. And AM showed 68.9% antioxidation capacity at 50% concentration by using a DPPH assay. Consequently, AM can be used as natural materials or additives for human skin owing to their beneficial biologic functions, including the anti-wrinkle effect, for cosmetic compositions.