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91.
《Arabian Journal of Chemistry》2020,13(12):8783-8792
The objective of this study was to assess the effects of stress on physiology/biochemical component of S. polyrhiza and its impact on CuNPs synthesis and bioethanol production. NaCl with RV5 provokes oxidative stress in S. polyrhiza and significantly increase MAD, Proline, H2O2, ROS, SOD and APX activity compare to control condition. Starch accumulation in S. polyrhiza was found 354% higher and correspond 4.4 times higher ethanol yield under stress condition compare to control. CuNPs were synthesized with an average size of 23–26 nm by purified fraction of APX having 37 KDa MW, 1.44 IU specific activity. Synthesized CuNPs were stable up to 15 consecutive cycles and potency against wide range of reactive dyes. The maximum remedial efficiency of synthesized CuNPs for COD and BOD was 55263.3 ± 3298.5 mg/m3min. and 30560.3 ± 1987.5 mg/m3min. respectively for RV5 wastewater. 0.072 mg/g of bioethanol was produced from the wet pulp remaining after nanoparticles synthesis. High efficiency of CuNPs and significant production of Ethanol, indicate that the feasibility for circular model for continuous industrial wastewater treatment. 相似文献
92.
《Arabian Journal of Chemistry》2022,15(10):104135
Justicia vahlii Roth. (acanthaceae) is an important medicinal food plant used in pain relief and topical inflammation. The present study aimed to evaluate phytochemical composition, toxicity, anti-inflammatory, antioxidant and enzyme inhibition potential of n-butanol extract of J. vahlii (BEJv). The extract prepared through maceration was found rich in total phenolic contents (TPC) 196.08 ± 6.01 mg of Gallic acid equivalent (mg GAE/g DE) and total flavonoid contents (TFC) 59.08 ± 1.32 mg of Rutin equivalent (mg RE/g DE). The UPLC-Q-TOF-MS analysis of BEJv showed tentative identification of 87 compounds and 19 compounds were detected in GC–MS analysis. The HPLC-PDA quantification showed the presence of 14 polyphenols amongst which kaempferol (3.45 ± 0.21 µg/ mL DE) and ferulic acid (2.31 ± 1.30 µg/ mL DE) were found in highest quantity. The acute oral toxicity study revealed the safety and biocompatibility of the extract up to 3000 mg/kg in mice. There was no effect of BEJv on human normal liver cells (HL 7702) and very low cytotoxic effect on liver cancer cells (HepG2) and breast cancer cells (MCF-7). In anti-inflammatory evaluation, the BEJv treated groups showed significant inhibition (p < 0.001) of late phase carrageenan induced paw edema at 400 mg/kg and increased the levels of oxidative stress markers; catalase, superoxide dismutase (SOD) and glutathione (GSH) while decreased the inflammatory markers; interleukin-1beta (IL-β) and tumor necrosis factor alpha (TNF-α) in paw tissue of mice. BEJv displayed highest results in Ferric reducing antioxidant power (FRAP) assay 97. 21 ± 2.34 mg TE (trolox equivalent)/g DE, and highest activity 3.32 ± 0.31 mmol ACAE (acarbose equivalent)/g D.E against α-glucosidase. Docking study showed good docking score by the tested compounds against the various clinically significant enzymes. Conclusively the current study unveiled J. vahlii as novel non-toxic source with good antioxidant-mediated anti-inflammatory potential which strongly back the traditional use of the species in pain and inflammation. 相似文献
93.
Ping-Jyun Sung Chen-Hao Pai Yin-Di Su Tsong-Long Hwang Tung-Yung Fan Jan-Jung Li 《Tetrahedron》2008,64(19):4224-4232
Four new 8-hydroxybriarane diterpenoids, including junceols A-C (1-3) and fragilide D (4), have been isolated from the gorgonian corals Junceella juncea and Junceella fragilis, respectively. The structures of briaranes 1-4 were elucidated by the interpretations of spectral data analysis. Briaranes 1-3 have displayed inhibitory effects on superoxide anion generation by human neutrophils. 相似文献
94.
Xanthine oxidase (XOD) inhibitors and superoxide anion scavengers play an important role in the treatment of gout and the inhibition of many diseases related to superoxide anion. The respective quantitation of uric acid and superoxide anion by traditional spectroscopic methods is routine in XOD inhibitors and superoxide anion scavengers screening at laboratories worldwide. In the present study, we established an ultrahigh performance liquid chromatography and triple quadrupole mass spectrometry (UHPLC–TQ-MS) method of higher accuracy and speed that combines screening of superoxide anion scavenger and XOD inhibitor in a single analysis by adding WST-1 (2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium sodium salt) to the enzymatic reaction. We applied the established method to determine the XOD inhibitory activities and superoxide scavenging activities of some herbal extracts and compounds from natural products, which could be classified into six groups based on the results of the assay. Our innovative protocol is fast, accurate and robust. Moreover, it can eliminate false positive and false negative results which may occur in the traditional spectroscopic methods. 相似文献
95.
《Analytical letters》2012,45(13):2033-2043
Abstract Cytochrome c was immobilized at didodecyldimethylammonium bromide (DDAB)‐modified powder microelectrode and presented quasi‐reversible electrochemistry. The apparent surface coverage of cytochrome c is greatly enhanced by using powder microelectrode technique, which is 1.21×10?8 mol/cm2, more than one to three orders of magnitude larger than that obtained with thiol and DNA‐modified Au electrode. The cytochrome c modified powder microelectrode was applied for the amperometric determination of superoxide generated by the reaction of hypoxanthine with xanthine oxidase (XOD) in the presence of dioxygen. The detection sensitivity of the modified powder microelectrode is 0.74 µA/cm2 µM, which is larger than that reported in previous publications. The detection limit of the modified powder microelectrode (PME) is 0.5 µM, and the linear detection range is 0.86~5.93 µM (values of the concentration are all in terms of hypoxanthine concentration in the solution). 相似文献
96.
《Analytical letters》2012,45(5):1047-1055
Abstract An amperometric enzyme modified carbon paste electrode for the detection of xanthinc by the xanthine oxidase catalyzed reaction is described. the product of the enzyme reaction monitored is the highly unstable radical superoxide, detected at O mV (vs SCE) poised potential. A dual working electrode configuration consisting of an enzyme modified carboa paste electrode and an unmodified glassy carbon electrode are utilized for this purpose. 相似文献
97.
Bing Chen Liang Chen Li‐Jun Gao Su‐Yu Ye Rui Xiao Pei‐Lian Liu Bi‐Lian Chen Yun‐Xia Zhang Jun Yao 《中国化学会会志》2012,59(4):520-524
A superoxide dismutase enzyme was extracted from the leaves of Agave Hybrid No.11648 using homogenisation, ammonium sulphate fractional precipitation, diethylaminoethyl cellulose ion exchange and Sephadex gel filtration chromatography. A superoxide dismutase parallelogram‐shaped crystal was formed after packing at 4 °C for two days. The optimum pH was 8, and the optimum temperature was 40 °C. The crystal was relatively stable at temperatures below 60 °C and at pH values from 5 to 10. The subunit size was determined to be approximately 27.5 kDa by sodium dodecyl sulphate‐polyacrylamide gel electrophoresis. It was also demonstrated that the enzyme is an iron‐containing superoxide dismutase based on its sensitivity to inhibitors of potassium cyanide, hydrogen peroxide and chloroform‐ethanol and based on the results of ultraviolet absorption spectroscopy. 相似文献
98.
99.
《Journal of Coordination Chemistry》2012,65(3):515-523
Two new isostructural copper(II)–zinc(II) complexes, [CuZnLBr2] (1) and [CuZnLCl2] (2) (H2L = N,N′-bis(4-methoxysalicylidene)cyclohexane-1,2-diamine), have been synthesized and characterized by elemental analyses, infrared spectroscopy, and single-crystal X-ray diffraction. Both complexes crystallize in the P-1 space group. The Cu in each complex is four-coordinate square planar with two imines and two phenolates of L. The Zn in each complex is four-coordinate tetrahedral with two phenolates of L and two halides (Br for 1 and Cl for 2). The superoxide dismutase (SOD) activity of the complexes indicates that both complexes are rudimentary models for SOD. 相似文献
100.
《Journal of Coordination Chemistry》2012,65(22):3926-3938
An unexpected mononuclear Ni(II) complex, [Ni(L2)2]·CH3OH (HL2 = 1-(2-{[(E)-3,5-dichloro-2-hydroxybenzylidene]amino}phenyl)ethanone oxime), has been synthesized via complexation of Ni(II) acetate tetrahydrate with HL1. HL1 and its corresponding Ni(II) complex were characterized by IR, 1H-NMR spectra, HRMS, as well as by elemental analysis, UV–vis, and emission spectroscopy. The crystal structure of the complex has been determined by single-crystal X-ray diffraction. Each complex links two other molecules into an infinite 1-D chain via intermolecular hydrogen bonds. Moreover, the electrochemical properties of the nickel complex were studied by cyclic voltammetry. Superoxide dismutase-like activities of HL1 and Ni(II) complex were also investigated. 相似文献