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51.
以蔗渣为原料,采用碱和微波辐射联合处理后用于里氏木霉纤维素酶的液态发酵。采用单因素试验与正交试验确定了最佳的处理条件为:0.30 mol/L的NaOH溶液浸泡,微波功率160 W,处理5 min。在此条件下得到的单位能耗的酶活净增值最高。后续发酵结束后,酶活较未经处理的蔗渣发酵后所得酶活有显著提高。其中,β-葡萄糖苷酶活、滤纸酶(FPase)活、羧甲基纤维素酶(CMCase)活分别提高了81.3%,88.2%,154.5%。 相似文献
52.
Dawe AS Nylund R Leszczynski D Kuster N Reader T De Pomerai DI 《Bioelectromagnetics》2008,29(2):92-99
Recent data suggest that there might be a subtle thermal explanation for the apparent induction by radiofrequency (RF) radiation of transgene expression from a small heat-shock protein (hsp16-1) promoter in the nematode, Caenorhabditis elegans. The RF fields used in the C. elegans study were much weaker (SAR 5-40 mW kg(-1)) than those routinely tested in many other published studies (SAR approximately 2 W kg(-1)). To resolve this disparity, we have exposed the same transgenic hsp16-1::lacZ strain of C. elegans (PC72) to higher intensity RF fields (1.8 GHz; SAR approximately 1.8 W kg(-1)). For both continuous wave (CW) and Talk-pulsed RF exposures (2.5 h at 25 degrees C), there was no indication that RF exposure could induce reporter expression above sham control levels. Thus, at much higher induced RF field strength (close to the maximum permitted exposure from a mobile telephone handset), this particular nematode heat-shock gene is not up-regulated. However, under conditions where background reporter expression was moderately elevated in the sham controls (perhaps as a result of some unknown co-stressor), we found some evidence that reporter expression may be reduced by approximately 15% following exposure to either Talk-pulsed or CW RF fields. 相似文献
53.
Microwave-accelerated methylation of starch 总被引:1,自引:0,他引:1
A novel microwave-accelerated method for methylating soluble starch is described. Soluble starch could be fully methylated in 72% yield within 4.66 min using iodomethane and 30% potassium hydroxide under microwave irradiation. The completely methylated starch thus obtained was hydrolyzed with 60% HCO(2)H for 1.5 min under 80% MW power, followed by 0.05 M H(2)SO(4) for 2.0 min under 100% MW power. The partially methylated monosaccharides were separated by preparative paper chromatography and identified by their melting points and optical rotations. 相似文献
54.
不同方法提取的艾叶挥发油指纹图谱分析 总被引:5,自引:0,他引:5
采取超临界CO2、微波和水蒸气蒸馏三种方法提取艾叶挥发油,利用GC-MS分析了不同方法提取的 艾叶挥发油指纹图谱。超临界CO2和微波萃取的艾叶挥发油的化学成分相似,水蒸气蒸馏与前两种方法提 取的挥发油的化学成分有些差异。超临界CO2萃取的艾叶挥发油更具天然性,超临界CO2萃取法为提取艾 叶挥发油的较理想方法;微波辅助萃取也不失为一种可行的方法。 相似文献
55.
微波辐射菘蓝种子的生物学效应研究 总被引:6,自引:1,他引:5
以菘蓝(Isatis indigotica Fort)为实验材料,研究了微波辐照中药菘蓝种子对幼苗光合色素含量、净光合速率、气孔导度与水分利用率、可溶性糖含量及幼苗生长发育的影响。研究结果表明:与对照相比,4种处理均能不同程度提高菘蓝幼苗光合色素含量、净光合速率水平、气孔导度与水分利用率,可溶性糖含量以及促进幼苗生长发育,比较而言8s微波预处理效果最好。并在此基础上讨论了微波的作用机理及影响幼苗光合作用的机理。 相似文献
56.
微波水解制备鱼蛋白的研究 总被引:6,自引:1,他引:5
采用微波水解的方法制备鱼蛋白水解液,结果表明:微波可以明显增加蛋白质回收率,正交实验得到微波酸解的最适条件,即HCl浓度4 mol·L-1、微波功率450w、作用时间为30min,其水解液的蛋白质回收率可达到91.02%,相当于酶解的效果,且腥苦昧较小。 相似文献
57.
58.
《Bioorganic & medicinal chemistry》2020,28(2):115231
Sirtuins (SIRT1–SIRT7) are an evolutionary conserved family of NAD+-dependent protein deacylases regulating the acylation state of ε-N-lysine residues of proteins thereby controlling key biological processes. Numerous studies have found association of the aberrant enzymatic activity of SIRTs with various diseases like diabetes, cancer and neurodegenerative disorders. Previously, we have shown that substituted 2-alkyl-chroman-4-one/chromone derivatives can serve as selective inhibitors of SIRT2 possessing an antiproliferative effect in two human cancer cell lines. In this study, we have explored the bioisosteric replacement of the chroman-4-one/chromone core structure with different less lipophilic bicyclic scaffolds to overcome problems associated to poor physiochemical properties due to a highly lipophilic substitution pattern required for achieve a good inhibitory effect. Various new derivatives based on the quinolin-4(1H)-one scaffold, bicyclic secondary sulfonamides or saccharins were synthesized and evaluated for their SIRT inhibitory effect. Among the evaluated scaffolds, the benzothiadiazine-1,1-dioxide-based compounds showed the highest SIRT2 inhibitory activity. Molecular modeling studies gave insight into the binding mode of the new scaffold-replacement analogues. 相似文献
59.
This paper reports a technique using microwaves to assist penetration of stains into biopsy sections of muscle and peripheral nerve. The technique results in more consistent and reliable staining of tissue sections for examination by light microscopy. 相似文献
60.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):1307-1315
An efficient and simple microwave assisted synthesis of sulfonamide derivatives incorporating the pyridazine moiety has been developed. These sulfonamides were used for the preparation of new heterocyclic compounds via reaction with different reagents using a microwave irradiation technique. The structures of the newly synthesized compounds were confirmed on the basis of FTIR, 1H and 13C-NMR, mass spectral techniques and elemental analyses. Some of the new synthesized compounds were assayed for their in vitro antibacterial activity against Gram-positive bacteria, Staphylococcus aureus and Staphylococcus epidermidis, Gram-negative bacteria, Escherichia coli and Klebsiella pneumonia and antifungal activity against Aspergillus fumigatus and Candida albicans. Most of the new compounds showed significant antibacterial and antifungal activity. 相似文献