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981.
Roheena Abdullah Wajeeha Zafar Muhammad Nadeem Mehwish Iqtedar Shagufta Naz Quratulain Syed 《Natural product research》2015,29(4):336-344
This study deals with the isolation of novel mutant of Bacillus and optimisation of media for the hyperproduction of cellulase. Cellulase-producing Bacillus PC-BC6 was subjected to physical and chemical mutagenesis to enhance the cellulolytic potential. Later, mutagenesis isolates were screened both qualitatively and quantitatively. Among all the tested isolates, Bacillus N3 yielded maximum (CMCase 1250 IU/mL/min and FPase 629 IU/mL/min) activity. The Bacillus N3 strain exhibited 1.7-fold more enzyme production as compared with the parental strain. Proximate analysis of untreated and pretreated Saccharum spontaneum was carried out to improve cellulase production. Three different media were tested for the production of cellulase, among which M2 medium containing MgSO4, pretreated S. spontaneum, K2HPO4, (NH4)2SO4 and peptone was found to be the best for maximum enzyme production by mutant Bacillus N3. 相似文献
982.
983.
Abdullah M. Asiri Salman A. Khan Saad H. Al-Thaqafy Kamlesh Sharma 《Journal of fluorescence》2015,25(3):503-518
984.
985.
Molecular structure investigation and biological evaluation of Michael adducts derived from dimedone
Assem Barakat Abdullah M. Al-Majid Mohammad Shahidul Islam Ismail Warad Vijay H. Masand Sammer Yousuf M. Iqbal Choudhary 《Research on Chemical Intermediates》2016,42(5):4041-4053
Trimolecular salt Michael adducts 2a–c were synthesized in excellent yields up to 92 % via one-pot multicomponent reactions in an aqueous medium. The chemical structures of compounds 2a–c were characterized by X-ray single-crystal diffraction techniques. Calculations of the density functional theory for the synthesized compound were performed. The stability of the products was deduced by TGA analysis. Compounds 2a–c were screened in vitro for different bio-assays such as thymidine phosphorylase inhibition assay, urease inhibition assay, β-glucuronidase inhibition assays and cytotoxicity against PC-3 and HeLa cell lines. 相似文献
986.
Synthesis,Characterization, and in vitro Cytotoxicity of Gold(I) Complexes of 2‐(Diphenylphosphanyl)ethylamine and Dithiocarbamates 下载免费PDF全文
Adam A. A. Sulaiman Muhammad Altaf Anvarhusein A. Isab Abdullah Alawad Saleh Altuwaijri Saeed Ahmad 《无机化学与普通化学杂志》2016,642(24):1454-1459
Gold(I) complexes of 2‐(diphenylphosphanyl)ethylamine or (2‐aminoethyl)diphenylphosphine (AEP), and dithiocaarbamates (R2NCS2) were prepared by the reaction of these ligands with (CH3)2S‐AuCl in dichloromethane. The synthesized complexes [Au(AEP)Cl] ( 1 ), [Au(AEP)2]Cl ( 2 ), and [Au2(R2NCS2)2]n (R2 = dimethyl ( 3 ), diethyl ( 4 ), and dibenzyl ( 5 )) were characterized by elemental analysis, IR, 1H, 13C and 31P NMR spectroscopy. The complexes were evaluated for anticancer activity against three cancer cells, A549 (human lung carcinoma), HCT15 (human colon cancer), and MCF7 (human breast cancer) cell lines. Three of the five tested complexes showed significant in vitro cytotoxicity and for A549, the inhibition effect of three compounds is greater than cisplatin. 相似文献
987.
Noof Ali Alenazi Khalid Ahmad Alamry Mahmoud Ali Hussein Mahmoud Abdelkhalek Elfaky Abdullah Mohamed Asiri 《先进技术聚合物》2019,30(6):1493-1505
Polyethersulfone (PES) has been widely used in membrane technology and used to purify water in water treatments application or as a dialyzer to purify blood in hemodialysis. In this work, PES was chemically modified by separately grafting two biomolecules, 4‐aminobenzenesulfonamide (ABS), and 4‐amino‐N‐(5‐methylisoxazol‐3‐yl)benzenesulfonamide (AMBS), on PES backbone, and these modified membranes were blended to unmodified PES, in 1:1 ratio, in order to obtain PES‐b‐PES‐ABS and PES‐b‐PES‐AMBS membranes. The first aim of this study is to measure the anticoagulant properties of the modified membrane by measuring the activated partial thromboplastin time (APTT) and prothrombin time (PT). The second aim of the study is to evaluate the antifouling properties of the modified PES membranes by examining its antimicrobial activity against two Gram‐negative bacteria, which are Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli); two Gram‐positive bacteria, which are Bacillus subtilis (B. subtilis) and Staphylococcus aureus (S. aureus); and a fungus, which is Candida albicans (C. albicans). The results showed that grafting of ABS and AMBS improved overall the hydrophilicity properties of the modified PES membranes. PES‐b‐PES‐ABS membranes showed better anticoagulant properties with 13 seconds for PT and 38 seconds for APPT, in comparison with the control sample (pure plasma), which showed 12 seconds for PT and 30 seconds for APPT. For antimicrobial tests, both PES‐b‐PES‐ABS and PES‐b‐PES‐AMBS membranes did not show any antibacterial activity, but when zinc oxide (ZnO) nanoparticles were added to the modified PES membranes in concentrations between 3% to 5% w/w, PES‐b‐PES‐ABS‐ZnO (M‐4 and M‐5), and PES‐b‐PES‐AMBS‐ZnO (M‐8 and M‐9) nanocomposite membranes showed antibacterial activity against P. aeruginosa and S. aureus. 相似文献
988.
Carbon nanotube (CNT), a well-known carbon-based nanomaterial has drawn much attention in many application fields including chemistry in the last few decades. Many researchers and scientists have shown huge interest to improve the extraction methodologies and adopt their applications in combination with chromatography technique. With respect to this, the exceptional applications of CNTs have been introduced as extraction sorbent due to their excellent inborn physical and chemical properties. In particular, CNTs have consistently been used as adsorbents in various techniques including solid-phase micro-extraction, solid-phase extraction, micro dispersive slid phase extraction, magnetic dispersive solid phase extraction, analytes enrichment, sample fractionation and clean-up as well as support for many derivatization reactions. Many research papers have discussed the successful use of CNTs to overcome the limitations of the extraction techniques due to their excellent sorbent capacity. In addition, considering the clear need to make chromatographic technique more successful, the applications of CNTs have been reported in the literatures in details as stationary and pseudo-stationary phases for the separation and extraction of challenging compounds. Because of the higher thermal and chemical stability, CNTs have been anticipated as stationary phase modifier for chromatographic applications to avoid bleeding of the columns and enable the analysis even at very high temperature (1200 °C). In liquid chromatography CNTs have primarily been used in combination with other packing materials (silica) and sometimes incorporated in a porous polymeric monolith. Therefore, the recent utilizations of CNTs as extraction materials and stationary phases have been illustrated in the current review and a table listing the details applications of CNTs in aforementioned field is provided as well. We believe that the review will help researcher to gain vast knowledge about application of carbon nanotubes in the field of separation chemistry. 相似文献
989.
Maged Abdeltawab El-Kemary Ibrahim Mahmoud El-mehasseb Shaymaa Elsayed El-Shafey Ola Ibrahim El-Shafey Hind Abdullah Aljohani 《Journal of Dispersion Science and Technology》2018,39(6):911-921
Calcined eggshell (CES) food residue was modified by depositing sol-gel titanium dioxide (TiO2) nanoparticles with narrow size distribution onto it through in situ precipitation and a novel hybrid nano biosorbent, namely TiO2-CES, was obtained. The deposition was characterized and the TiO2-CES nano network was used for efficient adsorption of single azo class anionic dye acid red nylon 57 (AN57) from aqueous solutions and the adsorption was pH dependent. Lower pH favored the sorption at the tested different pHs of 1.0–8.0. The calcination temperature had a cogent influence on the adsorption process. The sorption process reached equilibrium within 40?min, and the mathematical models were positively verified and could be described by a pseudo-second-order pattern, while equilibrium was described with Langmuir-type equation. In addition, the reusability study has proven that 0.5?M HNO3 was efficient enough to desorb AN57 from the hybrid nano sorbent. All results validated that TiO2-CES is Eco-Friendly adsorbent material practical treatment of dyes contaminated water. 相似文献
990.
Raju Suresh Kumar Abdulrahman I. Almansour Natarajan Arumugam Govindasami Periyasami S. Athimoolam Raju Ranjith Kumar Mohammad Asad Abdullah M. Asiri 《Tetrahedron letters》2018,59(35):3336-3340
The stereoselective syntheses of novel dispiro acenaphthylene–indolizine–pyridinone hybrid heterocycles have been achieved through one-pot four-component domino 1,3-dipolar cycloaddition–Michael addition–air oxidation sequence of reactions. 相似文献