International Journal of ChemTech Research | Year: 2010
More than sixty phase changing materials including organic, inorganic, eutectic and ionic liquids are reviewed here with respect to their thermal energy storage capacity. This review is based on some of their crucial properties like melting temperature, heat of fusion, thermal conductivity and density. After a rigorous study of their properties, a concluding list of nine promising phase changing materials appropriate for thermal energy storage is prepared. Due to lack of information of properties of some of the ionic liquids, we were unable to place them in the final list.
Prasad K.S.,M. S. University of Baroda |
Vaghasiya J.V.,Sardar Patel University |
Soni S.S.,Sardar Patel University |
Patel J.,ARIBAS |
And 4 more authors.
Applied Biochemistry and Biotechnology | Year: 2015
The cell-free extract, a crude enzyme (cytosolic and membrane fraction) obtained from an environmental isolate, Bacillus pumilus sp. BAB-3706 worked as excellent in reducing as well as stabilizing agent and facilitated the formation of stable colloidal selenium nanoparticles (SeNPs). Resulting nanoparticles were characterized using UV-vis spectrophotometer, TEM, EDAX, FT-IR and XRD, respectively. A working electrode was modified by coating the surface of indium tin oxide (ITO) with colloidal SeNPs. Successive additions of H2O2 (100 to 600 μM) in conventional three electrodes system, cyclic voltammeter with potential scan rate 25.0 mV/s, in 0.1 M phosphate buffer solution (PBS) yielded increase in current. A perpetual amperometric response at fixed potential (−1.0 V) and at selected time interval of 100 s showed different magnitude of current at every addition of H2O2. The linear range of detection of H2O2 was from 5 to 600 mM (R2 = 0.9965), while the calculated limit of detection was found to be 3.00 μM. The current study suggested that microbial SeNPs can be used for fabrication of low cost, sensitive H2O2 biosensor. © 2015, Springer Science+Business Media New York.
PubMed | CSIR - National Chemical Laboratory, Gujarat Biodiversity Gene Bank, har University, Sardar Patel University and 2 more.
Type: Journal Article | Journal: Applied biochemistry and biotechnology | Year: 2015
The cell-free extract, a crude enzyme (cytosolic and membrane fraction) obtained from an environmental isolate, Bacillus pumilus sp. BAB-3706 worked as excellent in reducing as well as stabilizing agent and facilitated the formation of stable colloidal selenium nanoparticles (SeNPs). Resulting nanoparticles were characterized using UV-vis spectrophotometer, TEM, EDAX, FT-IR and XRD, respectively. A working electrode was modified by coating the surface of indium tin oxide (ITO) with colloidal SeNPs. Successive additions of H2O2 (100 to 600 M) in conventional three electrodes system, cyclic voltammeter with potential scan rate 25.0 mV/s, in 0.1 M phosphate buffer solution (PBS) yielded increase in current. A perpetual amperometric response at fixed potential (-1.0 V) and at selected time interval of 100 s showed different magnitude of current at every addition of H2O2. The linear range of detection of H2O2 was from 5 to 600 mM (R(2)=0.9965), while the calculated limit of detection was found to be 3.00 M. The current study suggested that microbial SeNPs can be used for fabrication of low cost, sensitive H2O2 biosensor.
Varying influence on different biomarkers related to hepato-recovery events in liver-injured rats when treated with extracts of Andrographis paniculata, Phyllanthus amarus or their active principles individually and in combination
Bapat A.,Gargi Biotek Private Ltd |
Mukundan U.,Ramniranjan Jhunhunwala College |
Mukhopadhyaya P.N.,ABSL ISTRA |
Parekh H.,ABSL ISTRA |
And 2 more authors.
International Journal of Phytomedicine | Year: 2013
Water extracts of Phyllanthus amarus and Andrographis paniculata were used individually and in combination to investigate their hepato-recovery potential using carbon tetrachloride-treated, liver injured albino wistar rats. Toxicity study performed in female swiss albino mice was found to be satisfactory. HTPLC analysis revealed presence of andrographolide in A. paniculata and phyllanthin as well as gallic acid in P. amarus extracts. Histology analysis indicated extensive injury to liver tissue in experimental rats. Efficacy of polyherbal combination was less compared to individual extracts in reducing bilirubin concentration. SGPT and SGOT reduction by polyherbal combination was found to be similar to that of individual extracts. Co administration of extracts from both plants exhibited maximum reduction in γ GT concentration. However, polyherbal combination was not found to have any significant effect in reducing blood cholesterol when compared to individual extracts. Gallic acid, a component of P. amarus when used in pure form, was found to play significant role in reducing most liver injury biomarkers when compared to phyllanthin, the other active component of P. amarus. However, the latter was found to be more effective in reducing blood cholesterol compared to gallic acid. We concluded that polyherbal combination of A. paniculata and P. amarus does not always present a uniform, beneficial effect in cases of liver injury when monitored by several biomarkers. Further, gallic acid was found to be an equally important constituent of P. amarus extract along with phyllanthin in affecting hepato-protective activity in albino wistar rats.
Srivastava P.K.,University of Bristol |
Kiran G.S.,M. S. University of Baroda |
Gupta M.,Indian Institute of Technology Delhi |
Sharma N.K.,NVPAS |
International Journal of Ecology and Development | Year: 2012
Vegetable fields of sub-urban areas of Vadodara district, Gujarat, continue to receive the large amounts of extraneous heavy metals due to rapid urbanization and industrialization. A study was conducted to analyze the accumulated concentration of heavy metal contents in pea (Pisum sativum), lady's finger (Abelmoschus esculentus) and carrot (Daucus carota). A road density thematic map has been generated using the Geographic Information system (GIS) to visualize the anthropogenic sources of heavy metal contaminations in the vegetables. It has been found that the areas which are nearer to the dense road have higher amount of lead and cadmium content than the lower road density market. It was found that heavy metal contamination in vegetables collected from regular markets of Vadodara district, contains an elevated concentration of metal in comparison to the vegetables grown in biofresh farms. The concentration of Zinc was found to be highest in Pea followed by Lady's finger and Carrot in both suburban as well as biofresh vegetables. However, concentration of Cadmium was found to be highest in carrot. All vegetables either from suburban or biofresh market shows a remarkably lower concentration than Prevention of Food and Adulteration act (PFA) but higher than European Union (EU) standards. © 2011-12 IJED.
Ishnava K.B.,ARIBAS |
Chauhan J.B.,ARIBAS |
Saudi Journal of Biological Sciences | Year: 2013
In the present study, in vitro anticariogenic potential of ethyl acetate, hexane and methanol and aqueous extracts of plant leaves of Eucalyptus globules Labill. were evaluated by using four cariogenic bacteria, Lactobacillus acidophilus, Lactobacillus casei, Staphylococcus aureus and Streptococcus mutans. Agar well diffusion method and minimum inhibitory concentration (MIC) were used for this purpose. The ethyl acetate extracted fraction of plant leaves showed good inhibitory effects against all selected bacteria. In Eucalyptus globules, hexane and ethyl acetate extracts found highly effective against, Lactobacillus acidophilus with MIC value of 0.031 and 0.062 mg/mL, respectively. Qualitative phytochemical investigation of above extracts showed the presence of alkaloids, phenolic compounds, steroids, cardiac glycosides and terpenes. Based on the MIC value and bioautography, ethyl acetate of plant leaf was selected for further study. Further investigation on the structure elucidation of the bioactive compound using IR, GC-MS and NMR techniques revealed the presence of alpha-farnesene, a sesquiterpene. Eucalyptus globules plant leaf extracts have great potential as anticariogenic agents that may be useful in the treatment of oral disease. © 2012.
Patel P.S.,ARIBAS |
Raval J.P.,ARIBAS |
Asian Journal of Pharmaceutical and Clinical Research | Year: 2010
Compared to single-unit dosage forms, oral multi particulate drug-delivery systems like pellets, granules offer advantages in terms of a more even and predictable distribution and transportation in the gastro-intestinal tract. As the number of poorly soluble drugs has risen sharply in recent years, techniques for improving the solubility, and potentially, the bioavailability have become increasingly important. Melt extrusion technology represents an efficient pathway for increasing the solubility of poorly soluble drugs. In the drug the active forms a solid dispersion where the drug is presented in an amorphous state and molecularly dispersed in the carrier. This leads to an increase in solubility, as no lattice energy has to be overcome during dissolution. The particle size is reduced to the molecular level and the carrier increases the wetting of the drug. Scientists have tried to address such issues by various pharmaceutical interventions like various pelletizations, granulation and hot melt extrusion techniques available to prepare drug loaded spherical particles or granules. Amongst all extrusion is the most common method which utilized in formulation of beads and pellets. Limitations related to bioavailability and site specific drug delivery can be over come by this technique. This technology has gained focus because of its easy of operation and fast processing. Extrusion is widely utilized in formulation of sustained release, controlled release delivery system. Melt extrusion is considered to be an efficient technology with particular advantages over solvent processes like co-precipitation for the manufacture of a variety of dosage forms and formulations such as granules, pellets, tablets, suppositories, implants, stents, transdermal systems and ophthalmic inserts. This process is also useful from an ecological standpoint to produce solid dispersions efficiently without degradation. Potential drawbacks like the influence of heat stress and shear forces on the drug needs attention while doing extrusion. This review article describes the melt extrusion equipment, process and polymers used for formulation of various API using various pharmaceutical-grade polymers.