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81.
Yaacob Nor Suhaila Ramakrishnan Nagasundara Ramanan Mohamad Rosfarizan Ibrahim Abdul Latif Arbakariya Bin Ariff 《Annals of microbiology》2013,63(2):513-521
Phenol is a toxic compound and is one of the major pollutants contained in the waste water from petroleum and its downstream industries. Response surface methodology (RSM) was used to optimize medium composition and culture condition for enhancement of growth of Rhodococcus UKMP-5M and phenol degradation rate in shake flask cultures. Phenol and (NH4)2SO4 concentrations as well as temperature were the most significant factors that influenced growth and phenol degradation. Central composite design (CCD) was used for optimization of these parameters with growth, and degradation rates were used as the responses. Cultivation with 0.5 g/L phenol and 0.3 g/L (NH4)2SO4 and incubation at 36 °C greatly enhanced growth of Rhodococcus UKMP-5M, where the final cell concentration increased from 0.117 g/L to 0.376 g/L. On the other hand, the degradation rate was greatly increased in cultivation with 0.7 g/L phenol and 0.4 g/L (NH4)2SO4 and incubation at 37 °C. In this cultivation, the time taken to degrade 1 g/L phenol in the culture was reduced from 48 h to 27 h. The model for both responses was found significant and the predicted values were found to be in a good agreement with experimental values and subsequently validated. Increases in phenol degradation rate during Rhodococcus UKMP-5M cultivation corresponded well with increasing phenol hydroxylase activity. 相似文献
82.
Abdul Roouf Bhat Mohammad Arshad Eun Ju Lee Smritee Pokharel Inho Choi Fareeda Athar 《化学与生物多样性》2013,10(12):2267-2277
A new series of N‐(pyrimidin‐2‐yl)benzenesulfonamide derivatives, 3a – 3i and 4a – 4i , was synthesized from pyrimidin‐2‐amines, 2a – 2i , with the aim to explore their effects on in vitro growth of Entamoeba histolytica. The chemical structures of the compounds were elucidated by elemental analysis, FT‐IR, 1H‐ and 13C‐NMR, and ESI mass‐spectral data. In vitro anti‐amoebic activity was evaluated against HM1 : IMSS strain of Entamoeba histolytica. The IC50 values were calculated by using the double dilution method. The results were compared with the IC50 value of the standard drug ‘metronidazole’. The selected compounds were tested for their cytotoxic activities by cell‐viability assay using H9C2 cardiac myoblasts cell line, and the results indicated that all the compounds displayed remarkable >80% viabilities to a concentration of 100 μg/ml. 相似文献
83.
K. Muthamizh Selvan Gopi Govindhan Veeraswami Salvador Lyngdoh Bilal Habib Syed Ainul Hussain 《Mammalian Biology》2013,78(4):296-303
Prey selection and the feeding habits of tiger Panthera tigris, leopard Panthera pardus and Asiatic wild dog Cuon alpinus were investigated from June 2009 to December 2011 in Pakke Tiger Reserve, Arunachal Pradesh. A total of 422 scats were analyzed of which, 109 scats were of tigers, 150 were of leopard and 163 scats were of dholes. Multinomial Likelihood ratio test was used to estimate the prey selectivity of predators and Ivlev index, Pianka index were used to estimate prey preference and overlap respectively. Biomass consumption for three sympatric predators varied from 254.3 kg for dholes to 599.1 kg for tigers. Sambar, barking deer, wild pig were preyed more than their availability by all the predators. Ivlev index shows barking deer and sambar were preferred more than available prey for tiger where as leopard preferred sambar more than available and avoided barking deer. Dhole preferred more than available wild pig and barking deer. There was a high overlap between tiger–leopard (85.3%) and tiger–dhole (77.5%). To the best of our understanding, this study provides the first reliable information on prey selection and food habits of sympatric large carnivores in a protected area of Eastern Himalayan tropical rainforest. 相似文献
84.
85.
Ghias Uddin Abdul Latif Mohammad Arfan Mumtaz Ali Syed Hamid Hussain Thomas J. Simpson Russel J. Cox Muhammad Iqbal Choudhary 《Phytochemistry letters》2013,6(1):84-89
Three new phenolic compounds, sorlanin (4-(3-(hydroxymethyl)-5-methoxy-7-phenyl-2,3-dihydrobenzo[b][1,4]dioxin-2-yl)-2-methoxyphenol, 1), sorbanin (2-((3,5-dimethoxy-[1,1′-biphenyl]-4-yl)oxy)-1-(4-hydroxy-3-methoxyphenyl)propane-1,3-diol, 2) and sorbalanin (4-(3-(hydroxymethyl)-5,6-dimethoxy-2,3-dihydrobenzo[b][1,4]dioxino[2,3-g]benzofuran-2-yl)-2-methoxyphenol, 3), together with eight known compounds, polystachyol (4), isolariciresinol (5), dihydrodehydrodiconiferyl alcohol (6), tuberculatin (7), ovafolinin E (8), aucuparin (9), 2′-methoxyaucuparin (10), and tetracosyl-3-(3,4-dihydroxyphenyl)acrylate (11), were isolated from Sorbus lanata. The structures of these phytoconstituents were elucidated through extensive spectroscopic techniques, including UV, IR, 1D and 2D NMR, ESI-MS and HRESI-MS experiments. All the compounds except 9 and 10 were isolated for the first time from the genus Sorbus. The isolated compounds were also tested in DPPH radical scavenging reaction where compounds 6, 7, 10 and 11 showed significant activities with IC50 values of 9.2, 11.7, 23.0 and 33.7 μM, respectively. 相似文献
86.
Sumon Kumar Das Shahnawaz Ahmed Farzana Ferdous Fahmida Dil Farzana Mohammod Jobayer Chisti Daniel T. Leung Mohammad Abdul Malek Kaisar Ali Talukder Pradip Kumar Bardhan Mohammed Abdus Salam Abu Syed Golam Faruque Rubhana Raqib 《PloS one》2013,8(4)
Background
Shigellosis continues to be a public health challenge for developing countries, including Bangladesh. The aim of the study is to demonstrate recent changes in Shigella sero-groups and their geographical diversity.Methods
Data were extracted from data archive of four diarrheal disease surveillance systems. A 2% sub sample from urban Dhaka Hospital (2008–2011; n = 10,650), and 10% from urban Mirpur Treatment Centre (2009–2011; n = 3,585), were enrolled systematically; whereas, all patients coming from the Health and Demographic Surveillance System area in rural Matlab (2008–2011; n = 6,399) and rural Mirzapur (2010–2011; n = 2,812) were included irrespective of age, sex, and disease severity. A fresh stool specimen was collected for identification of Shigella spp. Of them, 315 (3%) were positive for Shigella in Dhaka, 490 (8%) from Matlab, 109 (3%) from Mirpur and 369 (13%) from Mirzapur and considered as analyzable sample size.Results
Among all Shigella isolates regardless of age, significant decreases in percentage of S. flexneri over time was observed in Mirpur (55→29%; p value of χ2-for trend = 0.019) and Mirzapur (59→47%; p = 0.025). A non-significant decrease was also seen in Dhaka (58→48%), while in Matlab there was a non-significant increase (73→81%). Similar patterns were observed among under-5 children at all sites. Emergence of S. sonnei was found in Dhaka (8→25%; p<0.001) and Mirpur (10→33%; p = 0.015), whereas it decreased in Mirzapur (32→23%; p = 0.056). The emergence of S. boydii was seen in all ages in Mirzapur [(3→28%; p<0.001); (3→27%; p<0.001)]. On the other hand, we saw non-significant percent reductions in S. boydii in Dhaka [overall (25→16%); under-5 (16→9%)]. Decreasing rates of Shigella dysenteriae were observed in Matlab, Mirpur and Mirzapur; whereas, in Dhaka it remained unchanged.Conclusion and Significance
Emergence of S. sonnei and S. boydii as important infectious diarrhea etiologies and variations in geographical diversity underscore the need for monitoring, with possible implications for vaccine development. 相似文献87.
88.
Abdul Malik S. A. Bazire A. Gamboa-Muñoz A. Bedoux G. Robledo D. García-Maldonado J. Q. Bourgougnon N. 《Microbiology》2020,89(6):778-788
Microbiology - Macroalgae host a dense bacterial epibiome forming surface biofilms, which act as a biological defense by protecting the surface from macrofoulers. During experimental cultivation of... 相似文献
89.
Muhammad S. Nadeem Mohammed Razeeth Hani M. Z. Choudhry Firoz Anwar Mazin A. Zamzami Bibi N. Murtaza Fahad A. M. Al-Abbasi Mohammad I. Khan Abdul R. Shakoori 《Journal of cellular biochemistry》2020,121(1):125-134
Escherichia coli is frequently exploited for genetic manipulations and heterologous gene expression studies. We have evaluated the metabolic profile of E. coli strain BL21 (DE3) RIL CodonPlus after genetic modifications and subjecting to the production of recombinant protein. Three genetically variable E. coli cell types were studied, normal cells (susceptible to antibiotics) cultured in simple LB medium, cells harboring ampicillin-resistant plasmid pET21a (+), grown under antibiotic stress, and cells having recombinant plasmid pET21a (+) ligated with bacterial lactate dehydrogenase gene grown under ampicillin and standard isopropyl thiogalactoside (IPTG)-induced gene expression conditions. A total of 592 metabolites were identified through liquid chromatography-mass spectrometry/mass spectrometry analysis, feature and peak detection using XCMS and CAMERA followed by precursor identification by METLIN-based procedures. Overall, 107 metabolites were found differentially regulated among genetically modified cells. Quantitative analysis has shown a significant modulation in DHNA-CoA, p-aminobenzoic acid, and citrulline levels, indicating an alteration in vitamin K, folic acid biosynthesis, and urea cycle of E. coli cells during heterologous gene expression. Modulations in energy metabolites including NADH, AMP, ADP, ATP, carbohydrate, terpenoids, fatty acid metabolites, diadenosine tetraphosphate (Ap4A), and l -carnitine advocate major metabolic rearrangements. Our study provides a broader insight into the metabolic adaptations of bacterial cells during gene manipulation experiments that can be prolonged to improve the yield of heterologous gene products and concomitant production of valuable biomolecules. 相似文献
90.
Heena Imtiaz Malik Abdul Rouf Mir Minhal Abidi Safia Habib Fahim Halim Khan 《Journal of biomolecular structure & dynamics》2020,38(7):1984-1994
AbstractAutoimmune responses against post-translationally modified antigens are a hallmark of several autoimmune diseases. In this work, we have studied the changes in alpha-2-macroglobulin (α2M) upon modification by peroxynitrite. Furthermore, we have evaluated the immunogenicity of modified α2M in experimental rabbits and rheumatoid arthritis (RA) patients. Peroxynitrite-modified α2M showed disturbed microenvironment and altered aromatic residues under UV and fluorescence studies. Aggregation, reduction in β-sheet content, production of nitrotyrosine and shift in amide I and II bands were observed in the modified α2M by polyacrylamide gel electrophoresis besides CD and FTIR spectroscopic analysis. The exposure of hydrophobic clusters and changes in contact positions were observed in ANS and ThT binding assays. Immunological studies using ELISA showed peroxynitrite-modified α2M as highly immunogenic producing high titre of specific antibodies in immunized rabbits. Cross-reactivity studies revealed the polyspecificity of the elicited antibodies. Direct binding ELISA and competitive inhibition studies confirmed the presence of circulating antibodies in the sera of RA patients having high specificity towards the peroxynitrite-modified α2M as compared to the native α2M. Sera from healthy (normal) human subjects showed lower binding with the native and modified protein. This study confirms that peroxynitrite induces structural modifications in α2M and makes it immunogenic. The presence of neo-antigenic determinants on modified α2M with enhanced binding for circulating autoantibodies in RA patients could offer new possibilities for diagnosis and etiopathology of the disease. Communicated by Ramaswamy H. Sarma 相似文献