• Title/Summary/Keyword: Co(II)

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Inhibition and Chemical Mechanism of Protocatechuate 3,4-dioxygenase from Pseudomonas pseudoalcaligenes KF707 (Pseudomonas pseudoalcaligenes KF707에서 유래한 protocatechuate 3,4-dioxygenase 의 저해 및 화학적 메커니즘)

  • Kang, Taekyeong;Kim, Sang Ho;Jung, Mi Ja;Cho, Yong Kweon
    • Journal of Life Science
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    • v.25 no.5
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    • pp.487-495
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    • 2015
  • We carried out pH stability, chemical inhibition, chemical modification, and pH-dependent kinetic parameter assessments to further characterize protocatechuate 3,4-dioxygenase from Pseudomonas pseudoalcaligenes KF707. Protocatechuate 3,4-dioxygenase was stable in the pH range of 4.5~10.5. L-ascorbate and glutathione were competitive inhibitors with $K_{is}$ values of 0.17 mM and 0.86 mM, respectively. DL-dithiothreitol was a noncompetitive inhibitor with a $K_{is}$ value of 1.57 mM and a $K_{ii}$ value of 8.08 mM. Potassium cyanide, p-hydroxybenzoate, and sodium azide showed a noncompetitive inhibition pattern with $K_{is}$ values of 55.7 mM, 0.22 mM, and 15.64 mM, and $K_{ii}$ values of 94.1 mM, 8.08 mM, and 662.64 mM, respectively. $FeCl_{2}$ was the best competitive inhibitor with a $K_{is}$ value of $29{\mu}M$. $FeCl_{3}$, $MnCl_{2}$, $CoCl_{2}$, and $AlCl_{3}$ were also competitive inhibitors with $K_{is}$ values of 1.21 mM, 0.85 mM, 3.98 mM, and 0.21 mM, respectively. Other metal ions showed noncompetitive inhibition patterns. The pH-dependent kinetic parameter data showed that there may be at least two catalytic groups with pK values of 6.2 and 9.4 and two binding groups with pK values of 5.5 and 9.0. Lysine, cysteine, tyrosine, carboxyl, and histidine were modified by their own specific chemical modifiers, indicating that they are involved in substrate binding and catalysis.

The Changes of Physiologic Parameters with Time in Steroid treated-Late Acute Respiratory Distress Syndrome Patients (스테로이드를 투여한 후기 급성호흡곤란증후군 환자에서 시간경과에 따른 생리학적 지표의 변화)

  • Jeon, Ik Soo;Suh, Gee Young;Koh, Won-Jung;Pyun, Yu Jang;Kang, Eun Hae;Ham, Hyoung Suk;Oui, Misook;Chung, Man Pyo;Kim, Hojoong;Kwon, O Jung
    • Tuberculosis and Respiratory Diseases
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    • v.54 no.4
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    • pp.429-438
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    • 2003
  • Background : The mortality from acute respiratory distress syndrome(ARDS) is >40-50%. Although some prospective trials have failed to demonstrate a survival benefit of steroids in the early stages of ARDS, there are some reports showing some success with steroids in the later stages. This study observed the changes in the physiologic parameters with time in late ARDS patients who were treated with steroids. Methods : The medical charts of 28 intensive care unit patients(male:female=24:4; mean age 64 years), who had been diagnosed with refractory late ARDS ($PaO_2/FIO_2$ <200) and were treated with corticosteroids from December 1999 to July 2002, were retrospectively reviewed. The patients were divided into two groups: the weaned group(n=14), which included the patients who had been successfully weaned from a ventilator after corticosteroid therapy, and the failed group(n=14), which included the patients who had failed weaning. The physiologic parameters included the $PaO_2/FIO_2$ ratio, the positive end-expiratory pressure(PEEP) level, the $PaCO_2$, compliance, the sequential organ failure assessment(SOFA) score, the acute physiologic and the chronic health evaluation(APACHE) II score, and the Murray Lung Injury Score(LIS) in the two groups were compared from the day of mechanical ventilation(Dmv) to 7 days after the corticosteroid therapy. Results : There was no significant difference in the clinical characteristics and the physiologic parameters between the two groups prior to the corticosteroid therapy except for the SOFA score at Dmv(weaned group : $6.6{\pm}2.5$ vs failed group : $8.8{\pm}2.9$, p=0.047). However, within 7 days after corticosteroid therapy, there was significant improvement in the $PaO_2/FIO_2$ ratio, the PEEP level, the $PaCO_2$, the SOFA score, the APACHE II score, and the LIS of the weaned group compared to the failed group. Conclusions : During corticosteroid therapy in late ARDS, the continuation of corticosteroid therapy should be determined carefully in patients who do not show improvement in their physiologic parameters by day 7.

Effects of Red-ginseng Extracts on the Activation of Dendritic Cells (고려홍삼의 수지상세포 활성화 효과)

  • Kim, Do-Soon;Park, Jueng-Eun;Seo, Kwon-Il;Ko, Sung-Ryong;Lee, Jong-Won;Do, Jae-Ho;Yee, Sung-Tae
    • Journal of Ginseng Research
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    • v.30 no.3
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    • pp.117-127
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    • 2006
  • Ginseng is a medicinal herb widely used in Asian countries. Dendritic cells(DCs) play a pivotal role in the initiation of T cell-mediated immune responses, making them an attractive cellular adjuvant for use in cancer vaccines. In this study, we examined the effects of Red-ginseng(water extract, edible and fermented ethyl alcohol extract, crude saponin) on the DCs phenotypic and functional maturation. Immature DCs were cultured in the presence of GM-CSF and IL-4, and the generated immature DCs were stimulated by water extract, edible and fermented ethyl alcohol extract, crude saponin and LPS, respectively, for 24hours. The expression of surface co-stimulatory molecules, including MHC(major histocompatibility complex) class II, CD40, CD80 and CD86, was increased on DCs that were stimulated with crude saponin, but antigen-uptake capacity was decreased. The antigen-presenting capacity of Red-ginseng extracts-treated DCs as analyzed by allogeneic T cells proliferation and IL-2, $IFN-{\gamma}$ production was increased. Furthermore, $CD4^+$ and $CD8^+$ syngeneic T cell(OVA-specific) proliferation and $IFN-{\gamma}$ production was significantly increased. However, $CD4^+$ syngeneic T cell secreted higher levels of IL-2 in responding but not $CD8^+$ syngeneic T cell. These results indicate the immunomodulatory properties of Red-ginseng extracts, which might be therapeutically useful in the control of cancers and immunodeficient diseases through the up-regulation of DCs maturation.

The Effect of Packing Method of Relining Material on the Flexural Strength of Denture Base Resin (첨상용 레진의 성형법이 의치상의 굴곡강도에 미치는 영향)

  • Kim, Min-Chul;Kim, Yu-Lee
    • Journal of Dental Rehabilitation and Applied Science
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    • v.27 no.2
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    • pp.197-207
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    • 2011
  • The study aimed at examining how different reline resins affect flexural strength and flexural modulus of denture base. A total of 80 specimens ($64{\times}10{\times}3.3$ mm, according to ISO 1567:1999) of heat-polymerized resin, 40 specimens for (Lucitone199(Dentsply Int., NewYork, USA), SR Ivocap(Ivoclar AG, Schaan, Liechtenstein)) respectively, were polymerized according to the manufacturer's instructions and divided into eight groups(n = 10). Control group specimens remained intact. Specimens in the other groups were abraded on both sides to 2 mm thickness, and were relined in 1.3 mm thickness with 3 types of resins (Lucitone199(Dentsply), SR Ivocap(Ivoclar), and Rebase II(Tokuyama Co., Ltd, Tokyo, Japan)). All specimens were preserved in distilled water at $37^{\circ}C$ for 50 hours, and then were subjected to flexural strength testing in a universal testing machine using 3-point loading. A crosshead speed of 5 mm/min was used, and the distance between the supports was 50 mm. Data analyses included one-way analysis of variance(ANOVA) and the Tukey Honestly Significant Difference test (p=.05). Both heat-polymerized resin groups and auto-polymerized resin groups showed statistically low flexural strength and flexural modulus than control groups. Specimens relined with Lucitone 199 showed significantly higher flexural strength and flexural modulus than those relined with SR-Ivocap. Specimens relined with auto-polymerized resin showed significantly lower flexural strength and flexural modulus than those relined with heat-polymerized resin. Relining with heat-polymerized resins showed superior mechanical properties to relining with an auto-polymerized resin. Relining with the same heat-polymerized resin as the denture base does not affect mechanical properties of a denture. Lucitone199 using a compression-mould technique resulted in the highest flexural strength.

In Vitro/In Vivo Development after Thawing of Vitrified Mouse Blastocysts by Culture Condition and Embryo Transfer Method (초자화 동결된 생쥐 배반포기배의 융해 후 배양조건과 수정란 이식방법에 따른 체외/체내발달)

  • Kim, M.K.;Kim, E.Y.;Yi, B.K.;Yoon, S.H.;Park, S.P.;Chung, K.S.;Lim, J.H.
    • Clinical and Experimental Reproductive Medicine
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    • v.24 no.3
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    • pp.347-353
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    • 1997
  • This study was to test whether in vitro/in vivo survival of vitrified mouse blastocysts was influenced by culture conditions and ET method. Mouse blastocysts were obtained from in vitro fertilization and cultured for 4 days in M16 medium, and they were vitrified in EFS40 which contained 40% ethlyene glycol, 18% Ficoll and 0.5 mol sucrose in PBS. In experiment I, in vitro and in vivo survival rate of these embryos were evaluated in different culture condition after thawing. When thawed embryos were cultured in M16 medium as a control, m-CR1 medium contained 20 amino acids (2% BME amino acis and 1% MEM non-essential amino acids solution) and 4 mg/ml BSA and cumulus monolayer cell co-cultured condition in mCR1 medium (10% FBS), their in vitro survival at 24 hr after thawing was not affected by culture condition (75.6, 83.1, 82.4%). However, in vivo survival rates of implantation in m-CR1 medium (80.4%) were significantly higher than those of M16 medium (51.2%), co-culture (57.1%) condition, although there was no difference in live fetuses rates on day 15 gestation (39.0, 49.0, 38.1%). In experiment II, the in vivo development potential of embryos by ET methods was examined. When blastocysts were transferred to the day 2, 3 pseudopregnant recipient without culture soon after thawing, no pregnant recipient was obtained on the day 2 pseudopregnancy, and 50% of pregnancy rates and 15.4% of live fetus rates were obtained on the day 3 pseudopregnant recipients. These results were significantly lower than those of transferred group (day 3 pseudopregnant recipients) after culture for 16 hr post thawing (73.5, 57.1%) (p<0.05). In experiment III, to elevate usability of delayed embryos in vitro/in vivo survival of vitrified embryos (day 4 early, day 5 early and expanding blastocyst) were examined. in vivo survival rates (live fetus, total implantation) were higher in day 4 early blastocysts (33.3, 66.7%) than in day 5 expanding blastocysts (29.0, 38.7%), although the highest in vitro survival rates were obtained in the day 5 expanding brastocysts (78.3%). Therefore, these results suggest that the in vitro/in vivo survival rates of vitrified embryos could be improve by the culture condition and ET method and that the in vivo development rates of delayed embryos were decreased with longer culture duration in vitro. It means that more effective cryopreservation was obtained in day 4 early blastocysts than in day 5 expanding blastocysts.

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High Glucose Induces Apoptosis through Caspase-3 Dependent Pathway in Human Retinal Endothelial Cell Line (인간망막 내피세포주에서 고농도 포도당이 caspase-3 경로를 통해 세포자연사 유도)

  • Seo, Eun-Sun;Chae, Soo-Chul;Kho, Eun-Gyeong;Lee, Jong-Bin
    • Korean Journal of Environmental Biology
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    • v.27 no.1
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    • pp.66-72
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    • 2009
  • Diabetic Retinopathy (DR) is a leading cause of blindness among adults in the western countries. Hyperglycemia is a condition, that induces apoptotic cell death in a variety of cell types in diabetes, but the mechanism remains unclear. The aim of the study is to understand the effects of high Glucose on Human Retinal Endothelial Cells. Retinal endothelial cells were cultured in Iscove's Modified Dulbecco's Medium (IMDM) containing 5, 25 and 50 mM Glucose, incubated for 24, 36 and 48 hours in humidified 5 % CO$_2$ incubator at 37$^{\circ}C$. Human Retinal Endothelial Cell Line (HREC) were characterized for morphology with different treatment by phase contrast microscopic analysis. Number of dead and viable cells was counted by trypan blue exclusion and supported by MTT assay. The intracellular Hydrogen peroxide (H$_2$O$_2$), a Reactive Oxygen Species (ROS) generation in high glucose conditions was assessed by FOX II assay and apoptosis by caspase-3 assay. The high glucose treated cells undergoing DNA fragmentation was witnessed by Agarose gel electrophoresis. We found that the cells incubated with 25 and 50 mM glucose containing medium for 48 hours altered the morphology of the cell, induced apoptosis and DNA fragmentation. The dead cell number were high in 25 and 50 mM when compared to the cells incubated with 5 mM glucose for 24, 36, and 48 hours. Also, the H$_2$O$_2$ levels and the activity of caspase-3 were increased in high glucose treated cells. Conclusions/interpretation: Our results demonstrated that elevated glucose induces apoptosis in cultured HREC. The hyperglycemia-induced increase in apoptosis may be dependent on caspase activation. The association between ROS generation and caspase-3 activation on high glucose treated cells is yet to be investigated.

Physiological studies on the sudden wilting of JAPONICA/INDICA crossed rice varieties in Korea -II. Artificial induction of sudden wilting in Korea and the effect of nutrio-physiological status (일(日)·인원연교잡(印遠緣交雜) 수도품종(水稻品種)의 급성위조증상(急性萎凋症狀) 발생(發生)에 관(關)한 영양생리학적(營養生理學的) 연구(硏究) -II. 한국(韓國)에서 급성위조증(急性萎凋症)의 인위적(人爲的) 재현(再現)과 영양생리(營養生理)의 영향(影響))

  • Kim, Yoo-Seob
    • Korean Journal of Soil Science and Fertilizer
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    • v.22 no.1
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    • pp.53-60
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    • 1989
  • The results of the investigation on the effects of plant nutrio-physiological status and reemergence of sudden wilting in rice on the occurrence of sudden wilting were summarized as follows: 1. The occurrence of sudden wilting, degree of damage and occurring time in the investigated variety showed to concur with the results of the previous experiment. 2. Nitrogen and Potassium contents in leaves related an occurrence of sudden wilting at heading stage have a very high negative co-relation (the value is -0.9224 at Yushin and -0.8243 at Milyang 23). 3. Regarding the relation between occurrence of sudden wilting and root activity capacity at the late growth stage, the root activity capacity at productive growth stage showed higher than at reproductive growth stage, which is the same in the two varieties but Milyang 23 is higher than Yushin. It is confirmed that root activity capacity in the two varieties has become very low at reproductive growth stage. 4. The toot activity capacity in the field with potassium showed a small occurrence of sudden wilting and the root activity capacity in the field with no potassium showed a very high co-relation value (the value is 0.8947 at Yushin and 0.7301 at Milyang 23). 5. Regarding the relation between the occurrence of sudden wilting and water evaporation quantity, water evaporation quantity after the heading date has a more direct relation to sudden wilting than that which occurrs prior to the heading date. Water evaporation quantity is higher in the field with no potassium, low leaves and Yushin, than in the field with potassium high leaves and Milyang 23. 6. The starch content in culm of Yushin and Milyang 23 at ripening stage showed high value in proportion to potassium quantity, and the starch content is lower as internode is lower. However, in fourth internode, the starch content is greatly increased in the field with potassium contrasted to the field with no potassium.

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Mineralogical and Geochemical Characteristics of the Precipitates in Acid Mine Drainage of the Heungjin-Taemaek Coal Mine (흥진태맥 석탄광 산성광산배수 침전물의 광물학적 및 지구화학적 특성)

  • Shin, Ji-Hwan;Park, Ji-Yeon;Kim, Yeongkyoo
    • Economic and Environmental Geology
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    • v.54 no.2
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    • pp.299-308
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    • 2021
  • Fe(II) released from mining activities is precipitated as various Fe(III)-oxyhydroxides when exposed to an oxidizing environment including mine drainage. Ferrihydrite, one of the representative precipitated Fe(III) minerals, is easy to adsorb heavy metals and other pollutants due to the large specific surface area caused by very low crystallinity. Ferrihydrite is transformed to thermodynamically more stable goethite in the natural environment. Hence, information on the transformation of ferrihydrite to goethite and the related mobility of heavy metals in the acid mine drainage is important to predict the behaviors of those elements during ferrihydrite to goethite transition. The behaviors of heavy metals during the transformation of ferrihydrite to goethite were investigated for core samples collected from an AMD treatment system in the Heungjin-Taemaek coal mine by using X-ray diffraction (XRD), chemical analysis, and statistical analysis. XRD results showed that ferrihydrite gradually transformed to goethite from the top to the bottom of the core samples. Chemical analysis showed that the relative concentration of As was significantly high in the core samples compared with that in the drainage, indicating that As was likely to be adsorbed strongly on or coprecipitated with iron oxyhydroxide. Correlation analysis also indicated that As can be easily removed from mine drainage during iron mineral precipitation due to its high affinity to Fe. The concentration ratio of As, Cd, Co, Ni, and Zn to Fe generally decreased with depth in the core samples, suggesting that mineral transformation can increase those concentrations in the drainage. In contrast, the concentration ratio of Cr to Fe increased with depth, which can be explained by the chemical bond of iron oxide and chromate, and surface charge of ferrihydrite and goethite.

A Study on the Evolution of 3,4-DCA and TCAB in Some Selected Soils(Part II) -Degradation of $^{14}C-3,4-DCA\;and\;^{14}C-TCAB$- (수종토양중(數種土壤中)에서 3,4-DCA 및 TCAB의 변화(變化)에 관(關)한 연구(硏究)(제2보(劑二報)) -$^{14}C-3,4-DCA$$^{14}C-TCAB$ 의 분해(分解)-)

  • Lee, Jae-Koo;Fournier, J.C.
    • Applied Biological Chemistry
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    • v.21 no.2
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    • pp.71-80
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    • 1978
  • In an attempt to elucidate the fate of 3,4-DCA and TCAB in various French soils, uniformly $^{14}C-ring-labeled$ 3,4-DCA and TCAB mere utilized and the following results obtained. 1) The rate of breakdown of $^{14}C-3,4-DCA$ into $^{14}CO_2$ was relatively higher in the early stage than that in the later stage. In 6 months of incubation in alkaline soil (pH 7.9), the rate was as high as 6.5% at dose 1 (1.5 ppm) and as low as 1.92% at dose 2(94 ppm), whereas in organic acid soil (pH 5.5) the rate was 4.91% at dose 1 and 4.24% at dose 2, respectively, without making any great difference between the two levels. 2) At dose 1, 47.70% of the initial radioactivity of $^{14}C-3,4-DCA$ was bound to soil in organic acid soil and 29.49% bound in alkaline soil, whereas at dose 2, 38.40% in organic acid soil and 20.30% in alkaline soil, respectively. 3) The amount of formation of $^{14}C-TCAB$ from $^{14}C-3,4-DCA$ seems to depend largely on the concentration of 3,4-DCA applied rather than on soil types. At dose 2, the amount was 50% of the total radioactivity extracted in organic acid soil and 30% in alkaline soil, corresponding to 1.8% and 1.4% of the initial radioactivity applied to soil, respectively. Cis-TCAB also seemed to be formed at dose 2 in both soils. Meanwhile, at dose 1, even though $^{14}C-TCAB$ was detected in trace on tlc and glc in both soils, the amount does not exceed 2 to 3% of the radioactivity extracted, corresponding to 0.05 to 0.1% of the initial radioactivity. 4) The rate of breakdown of $^{14}C-TCAB$ into $^{14}CO_2$ ranged from 0.05 to 0.20% in all the four soils. Most of the applied $^{14}C-TCAB$ remained intact after 3 months, not producing any detectable metabolites. 5) The fact that much more $^{14}C-TCAB$ was adsorbed to alkaline soil than to the other soils strongly indicates that in alkaline condition trans-isomer was converted tocisisomer which has the higher adsorption affinity than the former.

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Studies on the Enzymes Produced by Basidiomycetes -Part II. Properties of Cellulase and Xylanase- (담자균(擔子菌)이 생산(生産)하는 효소(酵素)에 관(關)한 연구(硏究) -제2보(第二報) Cellulase 및 Xylanase의 성질(性質)-)

  • Hong, Jai-Sik;Kwon, Yong-Ju
    • Applied Biological Chemistry
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    • v.24 no.4
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    • pp.260-266
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    • 1981
  • Some properties of cellulase and xylanase produced from Pleurotus ostreatus 301 and Lentinus edodes 3-1 during its growth in rice straw medium were investigated. The cellulase activities of P. ostreatus 301 and L. edodes 3-1 were increased in proportion to substrate concentration within 0.6% and 0.8%, respectively, and xylanase activities of two strains were increased within 1%. The reducing sugar production of cellulase and xylanase in two strains were proportionaly increased until 30 min. and 60 min. respectively. The opium pH for cellulase activities of P. ostreatus 301 and L. edodes 3-1 were pH 4.0 and pH 4.5, respectively, and xylanase activities of two strains were pH 5.0. The stable pH range for cellulase activities of P. ostreatus 301 was within 4.0 to 6.0 and L. edodes 3-1 was within 3.0 to 5.0, Xylanase activities of P. ostreatus 301 was within 4.5 to 6.0 and L. edodes 3-1 was within 3.5 to 6.0. The optium temperature for cellulase activities of P. ostraeatus 301 and L. edodes 3-1 were $40^{\circ}C$ and $50^{\circ}C$, respectively, but xylanase activities of P. ostreatus 301 and L. edodes 3-1 were $50^{\circ}C$ and $45^{\circ}C$, respectively. Thermal stability of enzymes were below of optimum temperature and these were mostly inactivate at $70^{\circ}C$ for 10 min of the metalic ions tested, cellulase activities of L. edodes 3-1 was increased by $Co^{++},\; Mg^{++}$ at the concentration of $10^{-2}M$, but were greatly inhibited by $Hg^{++},\;Cu^{++}$ in two strains. Xylanase activities were increased by $Ca^{++},\;Co^{++},\;Mg^{++}$ and $Cd^{++}$ but was greatly inhibited by $Hg^{++}$.

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