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21.
Biosorption is an eco-friendly and cost-effective method for treating the dye house effluents. Aspergillus niger and Trichoderma sp. were cultivated in bulk and biomasses used as biosorbents for the biosorption of an azo dye Orange G. Batch biosorption
studies were performed for the removal of Orange G from aqueous solutions by varying the parameters like initial aqueous phase
pH, biomass dosage, and initial dye concentration. It was found that the maximum biosorption was occurred at pH 2. Experimental
data were analyzed by model equations such as Langmuir and Freundlich isotherms, and it was found that both the isotherm models
best fitted the adsorption data. The monolayer saturation capacity was 0.48 mg/g for Aspergillus niger and 0.45 mg/g for Trichoderma sp. biomasses. The biosorption kinetic data were tested with pseudo first-order and pseudo second-order rate equations, and
it was found that the pseudo second-order model fitted the data well for both the biomasses. The rate constant for the pseudo
second-order model was found to be 10–0.8 (g/mg min−1) for Aspergillus niger and 8–0.4 (g/mg min−1) for Trichoderma sp. by varying the initial dye concentrations from 5 to 25 mg/l. It was found that the biomass obtained from Aspergillus niger was a better biosorbent for the biosorption of Orange G dye when compared to Trichoderma sp. 相似文献
22.
Sivaranjani Murugesan Prakash Manivannan Gowrishankar Shanmugaraj Rathna Janarthanam Pandian Shunmugiah Karutha Ravi Arumugam Veera 《Applied microbiology and biotechnology》2017,101(8):3349-3359
Applied Microbiology and Biotechnology - Alpha-mangostin (α-MG) has been reported to be an effective antibacterial agent against planktonic cells of many Gram-positive bacteria. However, the... 相似文献
23.
Electrochemical Energy Storage with a Reversible Nonaqueous Room‐Temperature Aluminum–Sulfur Chemistry 下载免费PDF全文
A reversible room‐temperature aluminum–sulfur (Al‐S) battery is demonstrated with a strategically designed cathode structure and an ionic liquid electrolyte. Discharge–charge mechanism of the Al‐S battery is proposed based on a sequence of electrochemical, microscopic, and spectroscopic analyses. The electrochemical process of the Al‐S battery involves the formation of a series of polysulfides and sulfide. The high‐order polysulfides (Sx2?, x ≥ 6) are soluble in the ionic liquid electrolyte. Electrochemical transitions between S62? and the insoluble low‐order polysulfides or sulfide (Sx 2?, 1 ≤ x < 6) are reversible. A single‐wall carbon nanotube coating applied to the battery separator helps alleviate the diffusion of the polysulfide species and reduces the polarization behavior of the Al‐S batteries. 相似文献
24.
Arumugam Dhanesh Gandhi Dhandapani Kayal Vizhi Kubendiran Lavanya V.N. Kalpana V. Devi Rajeswari Ranganathan Babujanarthanam 《Biochemistry and Biophysics Reports》2017
The main objective of this research is to investigate the anti-biofilm and anti-bacterial activity of Sesbania grandiflora (S. grandiflora) against Staphylococcus aureus. S. grandiflora extract were prepared and analyzed with UV –Vis spectroscopy, Fourier transform infrared spectroscopy, Dynamic light scattering. Biofilm forming pathogens were identified by congo-red assay. Quantification of Extracellular polymeric substance (EPS) particularly protein and carbohydrate were calculated. The efficacy of the herbal extract S. grandiflora and its inhibition against the pathogenic strain of S. aureus was also evaluated. The gradual decrease or disappearance of peaks reveals the reduction of protein and carbohydrate content in the EPS of S. aureus when treated with S. grandiflora. The antibacterial activity of S. grandiflora extract against the bacterial strain S. aureus showed that the extract were more active against the strain. To conclude, anti-biofilm and antibacterial efficacy of S. grandiflora plays a vital role over biofilm producing pathogens and act as a good source for controlling the microbial population. 相似文献
25.
Arumugam Karthikeyan 《Symbiosis (Philadelphia, Pa.)》2017,72(2):89-94
Impact of different levels of elevated CO 2 on the activity of Frankia (Nitrogen-fixing actinomycete) in Casuarina equisetifolia rooted stem cuttings has been studied to understand the relationship between C. equisetifolia, Frankia and CO2. The stem cuttings of C. equietifolia were collected and treated with 2000 ppm of Indole Butyric Acid (IBA) for rooting. Thus vegetative propagated rooted stem cuttings of C. equisetifolia were inoculated with Frankia and placed in the Open top chambers (OTC) with elevated CO2 facilities. These planting stocks were maintained in the OTC for 12 months under different levels of elevated CO2 (ambient control, 600 ppm, 900 ppm). After 12 months, the nodule numbers, bio mass, growth, and photosynthesis of C. equisetifolia rooted stem cuttings inoculated with Frankia were improved under 600 ppm of CO2. The rooted stem cuttings of C. equisetifolia inoculated with Frankia showed a higher number of nodules under 900 ppm of CO2 and cuttings without Frankia inoculation exhibited poor growth. Tissue Nitrogen (N) content was also higher under 900 ppm of CO2 than ambient control and 600 ppm levels. The photosynthetic rate was higher (17.8 μ mol CO2 m?2 s?1) in 900 ppm of CO2 than in 600 ppm (13.2 μ mol CO2 m?2 s?1) and ambient control (8.3 μ mol CO2 m?2 s?1). This study showed that Frankia can improve growth, N fixation and photosynthesis of C. equietifolia rooted stem cuttings under extreme elevated CO2 level conditions (900 ppm). 相似文献
26.
L. Muthulakshmi H. Nellaiah T. Kathiresan Fenila Christopher 《Preparative biochemistry & biotechnology》2017,47(5):458-467
In this work, two bioflocculants, namely, EB-EPS and B1-EPS, were derived from Enterobacter sp. and Bacillus sp., respectively, and analyzed with regard to their production and characterization. About 0.9 and 0.16?g of purified EB and B1 were obtained from I L of fermentation broth. Chemical analysis showed the contents of purified EB and B1 mainly as 88.7 and 92.8% (w/w) of carbohydrate, and 11.3 and 21.8% (w/w) protein, respectively. Fourier-transform infrared spectrometry analysis revealed the presence of hydroxyl, amide, and carboxyl groups in the identified bioflocculant. Thermogravimetric analysis (TGA) results exhibited enhanced thermal stability with a minimum mass loss of 50% while 25% were found to have occurred at higher temperatures (>400°C) for microbe-derived compounds EB and B1 leading to the possibility of using these compounds as fillers or for fabricating composite films for high-temperature applications. Further, the compounds from both the bacteria exhibited good antibacterial characteristics against pathogenic Escherichia coli. Degradability study of bioflocculant-embedded composite films shows the possibility of attaining eco-friendly bioremediation. Accordingly, experimental results revealed the suitability of developed composite films as a suitable alternative for food packaging and biomedical applications. 相似文献
27.
Haematococcus pluvialis is a unicellular green alga which produces a ketocarotenoid, astaxanthin which has pharmaceutical and nutraceutical applications
owing to its high antioxidant activity. Biotechnological approaches such as genetic transformation methods (Agrobacterium-mediated) and cloning strategies, are essential to improve/regulate this ketocarotenoid in Haematococcus. For this studies are necessary to improve Haematococcus through biotechnological means. In this connection, a suitable cocultivation medium for Haematococcus and Agrobacterium tumefaciens was standardized and different antibiotics were screened. Among the cocultivation media viz Z8, Bold’s Basal Medium, Tris Acetate Phosphate Z8 with 0.5% mannitol and BBM and Z8 with half strength LB TAP medium was found suitable for growth of both the alga Haematococcus and Agrobacterium. For the different antibiotics screened to identify the sensitivity of algae, hygromycin at more than 2 mg L−1 showed lethal effect which can be used as a selectable marker gene in genetic transformation, whereas cefotaxime and augmentin
showed no effect up to 2,000 mg L−1. The growth of algae was higher in solid selection medium when compared to the liquid selection medium. 相似文献
28.
Arumugam Geetha Panneerselvam Saranya Sam Annie Jeyachristy Rajagopal Surendran Arunachalam Sundaram 《Biological trace element research》2009,130(3):229-240
Altered copper homeostasis and oxidative stress have been observed in patients with hepatocellular carcinoma. Non-ceruloplasmin
copper, the free form, is a potent pro-oxidant than the protein bound copper. The aim of the present study was to evaluate
which form of copper can be correlated with the oxidative stress in the circulation and in the malignant liver tissues of
hepatocellular carcinoma patients. Hepatocellular carcinoma patients (grades II and III, n = 18) were enrolled in this study. Serum levels of total, free and bound copper, ceruloplasmin, iron, iron-binding capacity,
lipid peroxidation products, and enzymatic and non-enzymatic antioxidants were quantified in serum and in malignant liver
tissues and compared with those of normal samples (n = 20). A significant positive correlation between the serum non-ceruloplasmin copper and lipid peroxidation products and
negative correlation with antioxidants were observed in hepatocellular carcinoma patients. In liver tissue, glutathione peroxidase,
superoxide dismutase, and catalase activity were significantly decreased with concomitant elevation in oxidative stress markers.
Our experiment revealed that the elevation in non-ceruloplasmin copper has high relevance with the oxidative stress than the
bound copper. 相似文献
29.
Ravikumar Aruna Arumugam Geetha Periyanayagam Suguna 《Molecular and cellular biochemistry》2014,396(1-2):269-280
Inflammasomes are protein complexes formed in response to tissue injury and inflammation to regulate the formation of proinflammatory cytokines. Nod-like receptor pyrin domain containing 3 (NLRP3) is one such inflammasome involved in pancreatic inflammation. Caspase activation recruitment domain (CARD) is an interaction motif found in all the major components of NLRP3 inflammasome such as apoptosis associated speck-like CARD containing protein (ASC) and procaspase-1. NLRP3 activates procaspase-1 with the concerted action of CARD domain of ASC. In the present study, the effect of rutin, a natural flavonoid on the expression of ASC of NLRP3, was investigated in rats treated with ethanol (EtOH) and cerulein (Cer). Male albino Wistar rats were divided into four groups. Groups 1 and 2 rats were fed normal diet, whereas groups 3 and 4 rats were fed EtOH (36 % of total calories) containing diet for a total period of 5 weeks and also administered Cer (20 µg/kg body weight i.p.) thrice weekly for the last 3 weeks. In addition, groups 2 and 4 rats received daily 100 mg/kg body weight of rutin from third week. Rutin co-administration significantly decreased the level of pancreatic marker enzymes, oxidative stress markers, inflammatory markers, mRNA expression of caspase-1, cytokines, ASC–NLRP3, and protein expression of caspase-1 and ASC in rats received EtOH–Cer. The results of the study revealed that rutin can reduce inflammation in pancreas probably by influencing the down regulation of ASC–NLRP3 which might result in the reduced activation of caspase-1 and controlled cytokine production. 相似文献
30.
Mesoporous TiO2‐Sn/C Core‐Shell Nanowire Arrays as High‐Performance 3D Anodes for Li‐Ion Batteries 下载免费PDF全文
Three‐dimensional mesoporous TiO2‐Sn/C core‐shell nanowire arrays are prepared on Ti foil as anodes for lithium‐ion batteries. Sn formed by a reduction of SnO2 is encapsulated into TiO2 nanowires and the carbon layer is coated onto it. For additive‐free, self‐supported anodes in Li‐ion batteries, this unique core‐shell composite structure can effectively buffer the volume change, suppress cracking, and improve the conductivity of the electrode during the discharge‐charge process, thus resulting in superior rate capability and excellent long‐term cycling stability. Specifically, the TiO2‐Sn/C nanowire arrays display rechargeable discharge capacities of 769, 663, 365, 193, and 90 mA h g?1 at 0.1C, 0.5C, 2C 10C, and 30C, respectively (1C = 335 mA g?1). Furthermore, the TiO2‐Sn/C nanowire arrays exhibit a capacity retention rate of 84.8% with a discharge capacity of over 160 mA h g?1, even after 100 cycles at a high current rate of 10C. 相似文献