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文章研究旨在优化前期筛选到的米曲霉HML366产β-葡萄糖苷酶的培养基条件。通过单因素实验和响应面设计对米曲霉HML366产β-葡萄糖苷酶的培养基条件进行了优化组合,确定最佳的发酵培养基配方为:甘蔗渣3.49%,豆饼粉0.375%,KH2PO4 0.255%。在此培养条件下得到β-葡萄糖苷酶酶活力达92.64 U/g,是未优化前酶活71.12 U/g的1.30倍。 相似文献
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Apocynaceae系细胞尿苷二磷酸葡萄糖焦磷酸化酶的纯化和表征 总被引：3，自引：1，他引：3
祁超 《中国科学院研究生院学报》2004,21(3):345-351
经 4步分离纯化的Apocynaceae植物培养细胞尿苷二磷酸葡萄糖焦磷酸化酶(UGPase)的比活为 2 0 4 9U mg ,与细胞粗提液相比 ,活力提高 97倍 ,活力回收率为 2 1 %,可直接用于尿苷二磷酸葡萄糖 (UDPG)的合成 ,并且储存稳定性很好 .UGPase的最适pH值为 7 2 ,UGPase的最适温度为 37℃左右 .Mg2 是UGPase发挥活力所必需的 .高浓度UTP和Glc 6 P均能抑制UGPase的活力 相似文献
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目的:探讨稳恒磁场对家兔谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)活性的影响。方法:将20只家兔随机分为实验组与对照组。实验组每天进行一次磁处理,每次120min。稳恒磁场利用亥姆霍兹线圈产生,中心强度为22Gs。8周后测定两组家兔血清中GSH-Px和血液中CAT的活性。结果:实验组GSH-Px活性为(1426.50士156.72)活力单位/ml,CAT活性为(67.01士12.23)活力单位/L。对照组GSH-Px活性为(1178.25士270.36)活力单位/ml,CAT活性为(54.34士6.42)活力单位/L。实验组GSH-Px与CAT活性明显升高(P<0.05)。结论:稳恒磁场能够增强GSH-Px和CAT的活性,提高机体处理自由基的能力,增加机体的抵抗能力,具有一定的抗哀老功能。 相似文献
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一株嗜热梭菌β-葡聚糖酶基因的克隆和表达 总被引：1，自引：0，他引：1
提取嗜热梭菌(Clostridium.sp)基因组DNA,首次通过PCR克隆了该菌的β-葡聚糖酶基因全长,结果表明:该基因全长1040bp,ORF为1003bp,编码334个氨基酸,计算分子量为37.8kD,等电点为7.67。经Blast分析,该序列与热纤梭菌同源性最高(99%),而与基因库中嗜热梭菌的同源性为94%,该基因已被GenBank接受(AY225318)。用BamHⅠ和XhoⅠ双酶切目的片段和表达载体pET鄄30a( )后相连接,构建重组表达载体pET鄄clo,并导入BL21细菌中表达.酶学特性表明:SDS鄄PAGE电泳在37kD左右有表达蛋白带,该工程菌最适酶活29.4U/mL,是出发菌的15倍,最适温度在80℃左右,最适pH在9左右。该工程菌可构建耐热性好、酶活高的杂合基因工程菌。 相似文献
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老年人血小板谷胱甘肽过氧化物酶的纯化和分子特性研究 总被引：1，自引：0，他引：1
报道老年人血小板谷胱甘肽过氧化物酶由ＳｅｐｈａｒｏｓｅＱ柱层析、ＭｏｎｏＱＨＲ５／５ＦＰＬＣ和亲和层析后，经ＳＤＳ／ＰＡＧＥ鉴定为一条区带，其分子量为２３ｋＤａ．等电聚焦测定ＰＩ为５．１．用Ｓｕｐｅｒ－ｏｓｅＨＲ１０／３０柱经ＦＰＬＣ测定的分子量为９２ｋＤａ，这表明在自然状态下血小板谷胱甘肽过氧化物酶由四个相同的亚单位组成。这些结果与人红细胞谷胱甘肽过氧化物酶的特性相一致． 相似文献
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Jain A Mal J Mehndiratta V Chander R Patra SK 《Indian journal of clinical biochemistry : IJCB》2011,26(1):78-81
Vitiligo is an idiopathic, acquired, circumscribed, hypomelanotic skin disorder, characterized by milky white patches of different
sizes and shapes. It is due to the destruction of melanocytes resulting in the absence of pigment production of the skin and
mucosal surfaces. Oxidative stress has been implicated in pathophysiology of vitiligo. To study the activity of blood Superoxide
dismutase (SOD) and Glutathione peroxidase (GPx) in vitiligo patients. A case–control study was conducted in which 100 patients
were enrolled after written consent. 50 cases were of active vitiligo and 50 served as control (25 healthy control and 25
with stable vitiligo). SOD—In our study, among the active vitiligo cases 90% had high level of SOD and 10% had normal level
of SOD. Among the stable vitiligo controls, 92% had normal level of SOD and 8% had low levels of SOD.The difference between
active vitiligo cases and stable vitiligo control as well as with healthy control was statistically significant (P value < 0.05). GPx—Among the active vitiligo cases 74% had normal GPx levels, 22% had low and only 4% had high levels of
GPx. Among the stable vitiligo controls, 64% had normal GPx levels, 16% had low, and 20% had high levels of GPx. The difference
between active vitiligo cases and stable vitiligo control as well as with healthy control was statistically not significant
(P value > 0.05). Our study shows that oxidative stress is involved in the pathophysiology of vitiligo, as indicated by the
high levels of serum superoxide dismutase activity. 相似文献
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K. S. Motghare Anil Bhutey B. B. Murrhar Madhur Gupta A. W. Meshram Y. Balsubramanium 《Indian journal of clinical biochemistry : IJCB》2001,16(2):213-215
With the growing interest in the concept of free radicals in the pathogenesis of myocardial ischemia, it was thought worthwhile
to study the changes in lipid peroxides and antioxidant enzyme glutathione peroxidase (GPx) in ischemic heart disease (IHD).
The study was carried out on 76 patients of IHD-38 of acute myocardial infarction (AMI) and 38 of stable ischemic heart disease
(SIDH). They were age and sex matched with 38 normal healthy controls. A significant increase (p<0.001) in lipid peroxides
as malondialdehyde (MDA) (5.9±0.7 mmol/L) and a decrease in GPx (24.6±2.2 U/gmHb) was found in patients of AMI when compared
with controls. There was no significant difference in these values in SIHD. Thus this study confirms the earlier findings
that MDA and GPx are useful parameters in IHD and their magnitude is dependent on severity and/or duration of ischemia. We
suggest that these tests would be of use in smaller institutions with limited facilities. 相似文献
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R. Premanand K. V. S. Naidu K. Soorya Kumari K. K. Reddy 《Indian journal of clinical biochemistry : IJCB》1994,9(1):50-53
The concentration of serum lipid peroxides, tocopherol and glutathione peroxidase (GPx) activity was measured in 75 patients
(43 males and 32 females) of different respiratory diseases aged 15–40 years. The results were compared with the values obtained
from 100 healthy persons of comparabie age. The patients of respiratory diseases showed elevated levels of lipid peroxides
with concomitant reduction of tocopherol and glutathione peroxidase activity. When these patients were categorised into different
groups depending on the type of the disease like pulmonary tuberculosis (PT), chronic obstructive pulmonary disease (COPD),
pulmonary tuberculosis and chronic obstructive pulmonary disease (PT and COPD) and suppurative lung disease (SLD). There was
no significant difference between the groups. A significant inverse relation was found between lipid peroxides versus tocopherol
and glutathione peroxidase activity in patients of respiratory diseases. The results suggest the involvement of lipid peroxidation
process in pulmonary damage. 相似文献
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Shivananda Nayak Laxminarayana Udupa Saraswati Udupa 《Indian journal of clinical biochemistry : IJCB》2003,18(1):75-79
The effects of the alcoholic extract of the flowers ofIxora coccinea were studied on some of the antioxidant enzymes in dead space wounds created in rats. Increases in the tensile strength of
the wound and in the level of lysyl oxidase, the crucial enzyme for collagen maturation, were observed indicating a definite
prohealing action. In addition, a highly significant increase in the levels of catalase, glutathione peroxidase and glutathione
reductase was observed in the drug-treated group. Thus, the gain in tensile strength may be attributed not only to the better
cross-linking but also to the antioxidant properties of the drug. 相似文献
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T. K. Sankaranarayanan C. Subramanyam 《Indian journal of clinical biochemistry : IJCB》2003,18(1):1-4
A comparative study was conducted to evaluate calcineurin activity in normal pancreatic beta cells and insulinoma cells in
relation to their oxidative state. In comparison to normal islets, insulinoma cells had enhanced oxidative stress as evidenced
by increased content of thiobarbituric acid reactive substances. In addition, diminished activity of calcineurin in insulinoma
cells was concomitant with decreased content of reduced glutathione and glutathione peroxidase activity signifying diminished
antioxidant status in these cells. Culturing insulinoma cells in presence of the calcineurin inhibitor cyclosporin A resulted
in further decrease of calcineurin activity with restoration of glutathione peroxidase but without restoration of reduced
glutathione levels. These results indicate that an estimate of oxidative stress in pancreatic islets and insulinoma cells
can be obtained by assaying calcineurin activity. 相似文献
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Uric acid in urine was analyzed using porcine liver uricase and horseradish peroxidase immobilized on alkylamine and arylamine
glass beads (pore diameter 55nm) respectively. The minimum detection limit was 5.0mg/0.1 ml urine. The recovery of added uric
acid was 92%. Within and between assay CVS were <1.3% and <5.3% respectively. A good correlation (r=0.93) was found between
urinary urate values obtained by a commercial kit method and the present method. The uric acid in 24hr urine of apparently
healthy adults and person sufering from various diseases was found to be 450 to 900mg/24hr, 659mg/24hr (range, mean) and 910–1400mg/24hr,
1145 mg/24hr (range, mean) respectively with the present method. 相似文献
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Nasreen Noor Najmul Islam Shagufta Moin Abbas Ali Mahdi Sapna Jaiswal Farzana Bano 《Indian journal of clinical biochemistry : IJCB》2008,23(3):227-232
To probe the glutathione peroxidase (GPx) activity coupled to ROS and TNF-α levels in younger versus elderly primigravidas.
Monocytes were isolated from blood of young and elderly primigravidas after 12 hrs, 24 hrs and 14 days postpartum. Age-matched
healthy female donors served as controls. Thereafter, the above monocytes were subjected to evaluation of GPx activity, levels
of pro-inflammatory cytokine TNF-α and reactivity/specificity towards anti-TNF-α antibody. Suppression in GPx activity with
simultaneous enhancement of TNF-α levels in monocytes was observed after 12 hrs and 24 hrs of spontaneous labor pain-induced
maternal delivery through normal vaginal route. Conversely, an enhancement of GPx activity and decrease in TNF-α levels were
observed on day 14 of postpartum, thereby indicating reversal of the impaired neutralizing mechanisms. The antioxidant network
combating ROS was stronger in younger primigravidas. Capability of TNF-α and ROS suppression was somewhat lesser in elderly
primigravidas even 14 days of postpartum via normal vaginal route. The capability of GPx activity enhancement with simultaneous
suppression in ROS and TNF-α, decreases in elderly primigravidas. This may act as one of the important parameters leading
to a variety of complications encountered by elderly primigravidas. 相似文献