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101.
Bakshi Dapinder K. Gupta K.G. Sharma Prince 《World journal of microbiology & biotechnology》1999,15(4):507-509
Biodecolorization of a synthetic commercial textile dye effluent (0.1 gl–1) by Phanerochaete chrysosporium was enhanced by improving the original Kirk's medium with respect to buffer, C:N ratio, Mg2+ and Zn2+ ions, inoculum, temperature shifts, agitation and sunflower oil additon. An increase of 6.7-fold in lignin peroxidase (LIP) level, 4-fold in biomass and 45.5% enhanced decolorization of effluent was achieved. Degradation was both enzymatic (47.2%) and by biosorption (61.67%). 相似文献
102.
Thefirst-instar nymph and the adult female of Kermes echinatus Balachowsky (Hemiptera, Coccoidea, Kermesidae) are described and illustrated. This species is compared with Kermes vermilio Planchon, a morphologically similar species known in the Palaeractic region. 相似文献
103.
《Biotechnic & histochemistry》2013,88(5):321-324
AbstractMethylene green is a versatile dye that can be used in a wide range of technical applications, most of which require the dye to be pure. Because commercial lots of methylene green are known to be heterogeneous, we report a thin layer chromatographic method for checking purity. We also describe a simple and effective flash chromatographic purification procedure for subsequent purification. The identity and purity of the dye can be checked easily using UV-visible absorption spectrum measurements or by more sophisticated procedures if necessary. 相似文献
104.
Our project identified GFP labeled glial structures at the developing larval fly neuromuscular synapse. To look at development of live glial-nerve-muscle synapses, we developed a larval tissue preparation that had features of live intact larvae, but also had good optical properties. This new preparation also allowed for access of perfusates to the synapse. We used fly larvae, immersed them in artificial hemolymph, and relaxed their normal rhythmic body contractions by chilling them. Next we dissected off the posterior segments of each animal and with a blunt insect pin pushed the mouth parts backward through the body cavity. This everted the larval body wall, like turning a sock inside-out. We completed the dissection with ultra-fine dissection scissors and thus exposed the visceral side of the body wall muscles. The glial structures at the NMJ expressed membrane targeted GFP under the control of glial specific promoters. The post-synaptic membrane, the SSR (Subsynaptic Reticula) in muscle expressed synaptically targeted dsRed. We needed to acutely label the motor neuron terminals, the third part of the synapse. To do this we applied primary antibodies to HRP, conjugated to a far-red emitting flurophore. To test for dye diffusion properties into the perisynaptic space between the motor neuron terminals and the SSR, we applied a solution of large Dextran molecules conjugated to far-red emitting flurophore and collected images. 相似文献
105.
Qayyum Husain 《Critical reviews in biotechnology》2013,33(4):201-221
ABSTRACTRecently, the enzymatic approach has attracted much interest in the decolorization/degradation of textile and other industrially important dyes from wastewater as an alternative strategy to conventional chemical, physical and biological treatments, which pose serious limitations. Enzymatic treatment is very useful due to the action of enzymes on pollutants even when they are present in very dilute solutions and recalcitrant to the action of various microbes participating in the degradation of dyes. The potential of the enzymes (peroxidases, manganese peroxidases, lignin peroxidases, laccases, microperoxidase-11, polyphenol oxidases, and azoreductases) has been exploited in the decolorization and degradation of dyes. Some of the recalcitrant dyes were not degraded/decolorized in the presence of such enzymes. The addition of certain redox mediators enhanced the range of substrates and efficiency of degradation of the recalcitrant compounds. Several redox mediators have been reported in the literature, but very few of them are frequently used (e.g., 1-hydroxybenzotriazole, veratryl alcohol, violuric acid, 2-methoxy-phenothiazone). Soluble enzymes cannot be exploited at the large scale due to limitations such as stability and reusability. Therefore, the use of immobilized enzymes has significant advantages over soluble enzymes. In the near future, technology based on the enzymatic treatment of dyes present in the industrial effluents/wastewater will play a vital role. Treatment of wastewater on a large scale will also be possible by using reactors containing immobilized enzymes. 相似文献
106.
A new xanthene‐based two‐photon fluorescent probe for the imaging of 1,4‐dithiothreitol (DTT) in living cells
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Chao Wang Baoli Dong Xiuqi Kong Nan Zhang Wenhui Song Weiying Lin 《Luminescence》2018,33(6):1048-1053
1,4‐Dithiothreitol (DTT) has wide applications in cell biology and biochemistry. Development of effective methods for monitoring DTT in biological systems is important for the safe handling and study of toxicity to humans. Herein, we describe a two‐photon fluorescence probe (Rh‐DTT) to detect DTT in living systems for the first time. Rh‐DTT showed high selectivity and sensitivity to DTT. Rh‐DTT can be successfully used for the two‐photon imaging of DTT in living cells, and also can detect DTT in living tissues and mice. 相似文献
107.
Bilateral sensory disturbance after cortical spreading depression revealed by fluorescence imaging of voltage‐sensitive dye
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Cortical spreading depression (CSD), a propagation wave of transient neuronal and glial depolarization followed by suppression of spontaneous brain activity, has been hypothesized to be the underlying mechanism of migraine aura and triggers the headache attack. Evidence from various animal models accumulates since its first discovery in 1944 and provides support for this hypothesis. In this paper, alterations of bilateral cortical responses are investigated in a mice migrainous model of CSD using voltage‐sensitive dye imaging under hindlimb and cortical stimulation. After CSD induction in the right hemisphere, bilateral sensory responses evoked by left hindlimb stimulation dramatically decreases, whereas right hindlimb stimulation can still activate bilateral responses with an increased response of the left hemisphere and a well‐preserved response of the right hemisphere. In addition, cortical neural excitability remains after CSD assessed by direct activation of the right hemisphere in spite of the sensory deficit under contralateral hindlimb stimulation. These results depict the sensory disturbance of bilateral hemispheres after CSD, which may be helpful in understanding how sensory disturbance occur during migraine aura. 相似文献
108.
About 85% of the fatty acids liberated during the manufacture of black tea can be attributed to autolysis of 4 major polar lipid classes in tea leaf tissue, phosphatidylcholine, monogalactosyldiglyceride, digalactosyldiglyceride and phosphatidylethanolamine. Linolenic, linoleic and palmitic acids are the principal fatty acids released from these lipids and they all undergo further degradation. Linolenic acid (60% of fatty acids released) is derived mainly from galactolipids and thus the upper limit of release is dependent on the chloroplast maturity and content of the leaf tissues. Lipid breakdown is complete after 2 hr fermentation and, as there appears to be no accumulation of long chain fatty acid intermediates, it is probable that volatile production has also ceased at this time. 相似文献
109.
Molecular dynamics study of biodegradation of azo dyes via their interactions with AzrC azoreductase
Hamed Haghshenas Maryam Kay Fariba Dehghanian 《Journal of biomolecular structure & dynamics》2016,34(3):453-462
Azo dyes are one of the most important class of dyes, which have been widely used in industries. Because of the environmental pollution of azo dyes, many studies have been performed to study their biodegradation using bacterial systems. In present work, the AzrC of mesophilic gram-positive Bacillus sp. B29 has been considered to study its interaction with five common azo dyes (orange G, acid red 88, Sudan I, orange I, and methyl red). The molecular dynamics simulations have been employed to study the interaction between AzrC and azo dyes. The trajectory was confirmed using root mean square deviation and the root mean square fluctuation analyses. Then, the hydrogen bond and alanine scanning analyses were performed to reveal active site residues. Phe105 (A), Phe125 (B), Phe172 (B), and Pro132 (B) have been found as the most important hydrophobic residues whereas Asn104 (A), Tyr127 (B), and Asn187 (A) have key role in making hydrogen bond. The results of molecular mechanics Poisson–Boltzmann surface area and molecular mechanics generalized Born surface area calculations proved that the hydrophobic azo dyes like Acid red 88 binds more tightly to the AzrC protein. The calculated data suggested MR A 121 (B) I as a potential candidate for improving the AzrC–MR interactions. 相似文献
110.
James J. H. St Clair Barbara C. Klump Jessica E. M. van der Wal Shoko Sugasawa Christian Rutz 《Biological journal of the Linnean Society. Linnean Society of London》2016,118(2):226-232
Functional tool use requires the selection of appropriate raw materials. New Caledonian crows Corvus moneduloides are known for their extraordinary tool‐making behaviour, including the crafting of hooked stick tools from branched vegetation. We describe a surprisingly strong between‐site difference in the plant materials used by wild crows to manufacture these tools: crows at one study site use branches of the non‐native shrub Desmanthus virgatus, whereas only approximately 7 km away, birds apparently ignore this material in favour of the terminal twigs of an as‐yet‐unidentified tree species. Although it is likely that differences in local plant communities drive this striking pattern, it remains to be determined how and why crows develop such strong site‐specific preferences for certain raw materials. 相似文献