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1.
Environ Monit Assess ; 194(12): 877, 2022 Oct 13.
Article in English | MEDLINE | ID: mdl-36229620

ABSTRACT

Flowering exhibits a significant relationship with environmental stimuli and changes. Effect of photoperiodism and vernalization have been well studied in flowering phenology; however, the effect of soil temperature on flowering is less explored which is one of the major factors of vegetation growth in alpine ecosystem. This study thus focuses on the effects of soil and air temperature on flowering response of Rhododendron arboreum Sm., a Himalayan tree species, which is also an indicator of spring initiation in high altitude regions. To monitor the flowering pattern, we employed automated phenocam, which was set up at 3356 masl in Tungnath (Indian Alpine region of Uttarakhand) for time-lapse photography of timberline ecotone. Soil and air temperature were recorded continuously at the timberline ecotone. Three years (2017 to 2020) of datasets were used for the present study. The phenocam observations displayed an interesting event in the year 2019-2020 with complete absence of flowering in R. arboreum population at Tungnath timberline ecotone. From the soil temperature data, an increase in winter (Dec-Jan, during which floral buds form) soil temperature, by > 1 °C, and no accumulation of freezing degree-days were found for the year 2019-2020. Air temperature however did not display any relationship with the failure of flowering, ruling out aerial chilling or frost injury of floral buds. From the results, a possible relationship between soil temperature and flowering can be suggested pointing towards necessary root apex vernalization stimulus in shallow rooted Rhododendrons. However, the dependency of flowering in Rhododendrons on winter soil temperature further requires continuous monitoring and more observations to make concrete inferences.


Subject(s)
Rhododendron , Climate Change , Ecosystem , Environmental Monitoring , Rhododendron/physiology , Seasons , Soil , Temperature
2.
Environ Monit Assess ; 194(6): 420, 2022 May 11.
Article in English | MEDLINE | ID: mdl-35543773

ABSTRACT

Globally, the treelines at higher elevations in mountains are reported to be advancing up-slope in response to recent climate warming. However, little is known about the treeline advancement in the Himalaya due to paucity of baseline vegetation data with which to compare, thus making their assessment and monitoring challenging. To fill this knowledge gap, the present study documented floristic and functional diversity of two treeline ecotone sites in Kashmir Himalaya. At each site, we conducted field sampling by laying five 20-m2 plots, with one at the highest limit (T0 plot), two plots below and two above the treeline and two nested subplots of 5-m2 for shrubs and five 1-m2 for herbs in each plot. We recorded 97 plant species belonging to 33 families from the two sites. We observed a considerable difference in species composition and distribution along the treeline ecotone. Majority of the species reported were perennial herbs. We observed a significant association of growth forms with the particular plots along the treeline ecotone. At both the sites, we recorded highest species richness at the T0 plot which was correlated well with the functional traits, thus indicating convergence of floristic and functional diversity at this transition zone. Interestingly, the T0 plot at both the sites showed maximum overlap of species with the plots above and below the treeline. In an era of climate warming, our study provides crucial baseline data that will facilitate assessment and monitoring of the Himalayan treelines.


Subject(s)
Environmental Monitoring , Trees , Altitude , Climate , Climate Change , Humans , Trees/physiology
3.
Ecotoxicol Environ Saf ; 239: 113650, 2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35605326

ABSTRACT

This paper focuses on vegetation health conditions (VHC) assessment and mapping using high resolution airborne hyperspectral AVIRIS-NG imagery and validated with field spectroscopy-based vegetation spectral data. It also quantified the effect of mining on vegetation health for geo-environmental impact assessment at a fine level scale. In this study, we have developed and modified vegetation indices (VIs) based model for VHC assessment and mapping in coal mining sites. We have used thirty narrow banded VIs based on the statistical measurement for suitable VIs identification. The highest Pearson's r, R2, lowest RMSE, and P values indices have been used for VIs combined pixels analysis. The highest different (Healthy vs. unhealthy) vegetation combination index (VCI) has been selected for VHC assessment and mapping. We have also compared VIs model-based VHC results to ENVI (software) forest health tool and Spectral-based SAM classification results. The 1st VCI result showed the highest difference (72.07%) from other VCI. The AUC values of the ROC curve have shown a better fit for the VIs model (0.79) than Spectral classification (0.74), and ENVI FHT (0.68) based on VHC results. The VHC results showed that unhealthy vegetation classes are located at low distances from mine sites, and healthy vegetation classes are situated at high distances. It is also seen that there is a highly significant positive relationship (R2 =0.70) between VHC classes and distance from mines. These results will provide a guideline for geo-environmental impact assessment in coal mining sites.


Subject(s)
Coal Mining , Forests , Hyperspectral Imaging , Environment , Environmental Monitoring/methods , Spectrum Analysis
4.
J Environ Manage ; 289: 112504, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-33839612

ABSTRACT

This work mainly focused on deforestation susceptibility (DS) assessment and its prediction based on statistical models (FR, LR & AHP) in the Saranda forest, India. Also, efforts had been made to quantify the effect of mining on deforestation. We had considered twenty-five (twenty present and five predicted) causative variables of deforestation, including climate, natural or geomorphological, forestry, topographical, environmental, and anthropogenic. The predicted variables have been generated from different simulation models. Also, very high-resolution, Google Earth imagery have been used in time series analysis for deforestation from 1987 to 2020 data and generated dependent variable. On deforestation analysis, it was observed that a total of 4197.84 ha forest areas were lost in the study region due to illegal mining, agricultural and tribal people allied activities. The DS results have shown that of total existing forest area, 11.22% area were under very high, 16.08% under high, 16.18% under moderate, 24.25% under low, and 32.27% falls very low categories. According to the DS assessment and predicted results, the very high susceptibility classes were found at and close to mines, agricultural, roads and settlement's surrounding sites. The sensitivity analysis results also shown that some causative variables (maximum temperature (2.95%), minimum temperature (0.51%), rainfall (2.69%), LST (4.56%), hot spot (7.36%), aspect (1.14%), NDVI (2.64%), forest density (3.78%), lithology (3.26%), geomorphology (3.00%), distance from agricultural (19.40%), soil type (2.05%), solar radiation (5.97%), LULC (3.26%), drought (3.16%), altitude (2.85%), slope (5.97%), distance from mines (18.05%), roads (2.17%), and settlements (5.18%)) were more sensitive to deforestation. Most of the sensitive parameters showed a positive correlation with DS. The AUC values of the ROC curve had shown a better fit for AHP (0.72) than (0.69) FR and LR (0.68) models for present DS results. The correlation results had shown a good inverse relationship between DS and distance from mines and foliar dust concentration. This work will espouse the future work in the effective planning and management of the mining-affected forest region and predicted deforestation susceptibility would be helpful for forest ecosystem study and policymaking.


Subject(s)
Conservation of Natural Resources , Ecosystem , Forestry , Forests , Humans , India , Trees
5.
Insect Biochem Mol Biol ; 127: 103459, 2020 12.
Article in English | MEDLINE | ID: mdl-32961323

ABSTRACT

MicroRNAs (miRNAs) constitute a novel class of gene expression regulators and are found to be involved in regulating a wide range of biological processes such as development, cell cycle, metabolism, apoptosis, immunity, host-pathogen interactions etc. Generally miRNAs negatively regulate the gene expression at the post-transcriptional level by binding to the complementary target mRNA sequences. These tiny molecules are abundantly found in higher eukaryotes and viruses. Most of the DNA viruses of animals and insects encode miRNAs including baculoviruses. Baculoviruses are the insect-specific viruses that cause severe infection and mortality mainly in insect larvae of the order Lepidoptera, Diptera, and Hymenoptera. These enveloped viruses have multiple applications in biotechnology and biological pest control methods. For a better understanding of baculoviruses, it is necessary to elucidate the molecular basis of insect-baculovirus interactions. Recent advancement in the technologies for studying the gene expression has accelerated the discovery of new players in the insect-baculovirus interactions. MiRNAs are the emerging and fate-determining players of host-viral interactions. The long history of host and virus co-evolution suggests that the virus keeps on evolving its arsenals to succeed in infection whereas the host continues investing in antiviral defense mechanisms. In this review, I aim to highlight the recent information and understanding of the baculovirus-encoding miRNAs and their functions in regulating viral as well as host genes. Additionally, insect-derived miRNAs response to baculovirus infection is also discussed. A detailed critical view about the regulatory roles of miRNAs in insect-baculovirus interactions will help us to understand molecular networks amid these interactions and develop a sustainable antiviral strategy.


Subject(s)
Host-Pathogen Interactions , Insecta/genetics , MicroRNAs/genetics , Animals , Baculoviridae , Insecta/metabolism , Insecta/microbiology , MicroRNAs/metabolism
6.
Front Plant Sci ; 10: 527, 2019.
Article in English | MEDLINE | ID: mdl-31134105

ABSTRACT

Wheat genetic improvement by integration of advanced genomic technologies is one way of improving productivity. To facilitate the breeding of economically important traits in wheat, SNP loci and underlying candidate genes associated with the 36 agro-morphological traits were studied in a diverse panel of 404 genotypes. By using Breeders' 35K Axiom array in a comprehensive genome-wide association study covering 4364.79 cM of the wheat genome and applying a compressed mixed linear model, a total of 146 SNPs (-log10 P ≥ 4) were found associated with 23 traits out of 36 traits studied explaining 3.7-47.0% of phenotypic variance. To reveal this a subset of 260 genotypes was characterized phenotypically for six quantitative traits [days to heading (DTH), days to maturity (DTM), plant height (PH), spike length (SL), awn length (Awn_L), and leaf length (Leaf_L)] under five environments. Gene annotations mined ∼38 putative candidate genes which were confirmed using tissue and stage specific gene expression data from RNA Seq. We observed strong co-localized loci for four traits (glume pubescence, SL, PH, and awn color) on chromosome 1B (24.64 cM) annotated five putative candidate genes. This study led to the discovery of hitherto unreported loci for some less explored traits (such as leaf sheath wax, awn attitude, and glume pubescence) besides the refined chromosomal regions of known loci associated with the traits. This study provides valuable information of the genetic loci and their potential genes underlying the traits such as awn characters which are being considered as important contributors toward yield enhancement.

7.
Plant Signal Behav ; 10(3): e993264, 2015.
Article in English | MEDLINE | ID: mdl-25751309

ABSTRACT

Floral malformation is a main constraint to reduce fruit yield in mango plants. Recently, we report on the role of putrescine in normalizing the functional morphology of mango flower by reducing various adverse effects of ethylene. Here, ethrel, an ethylene releasing compound, was exogenously applied to mango plant cv Amrapali to evaluate the response of flower development under high level of ethylene. Scanning electron microscopy (SEM) study showed that ethrel treated flowers were observed to progressively be deformed and remain unbloom. The flower buds were not distinguishable and flower parts such as petals, sepals, anther and stigma were not properly developed. The stamen showed fused anther lobes and carpel depicted curved style with pointed stigma. The findings of present study suggest the involvement of ethylene to abort the functional morphology of flower and thereby development of malformation.


Subject(s)
Ethylenes/metabolism , Flowers/growth & development , Mangifera/metabolism , Organophosphorus Compounds/pharmacology , Plant Diseases , Flowers/drug effects , Flowers/metabolism , Mangifera/drug effects , Microscopy, Electron, Scanning/methods , Plant Development/drug effects , Putrescine/pharmacology
8.
Insect Biochem Mol Biol ; 49: 59-69, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24698834

ABSTRACT

During the last decade, microRNAs (miRNAs) have emerged as fine tuners of gene expression in various biological processes including host-pathogen interactions. Apart from the role of host encoded miRNAs in host-virus interactions, recent studies have also indicated the key role of virus-encoded miRNAs in the regulation of host defense responses. In the present study, we show that bmnpv-miR-3, a Bombyx mori nucleopolyhedrovirus (BmNPV) encoded miRNA, regulates the expression of DNA binding protein (P6.9) and other late genes, vital for the late stage of viral infection in the host, Bombyx mori. We have performed both cell culture and in vivo experiments to establish the role of bmnpv-miR-3 in the infection cycle of BmNPV. Our findings showed that bmnpv-miR-3 expresses during early stage of infection, and negatively regulates the expression of P6.9. There was an upregulation in P6.9 expression upon blocking of bmnpv-miR-3 by Locked Nucleic Acid (LNA), whereas overexpression of bmnpv-miR-3 resulted in a decreased expression of P6.9. Besides, a remarkable enhancement and reduction in the viral loads were observed upon blocking and overexpression of bmnpv-miR-3, respectively. Furthermore, we have also assessed the host immune response using one of the Lepidoptera-specific antimicrobial proteins, Gloverin-1 upon blocking and overexpression of bmnpv-miR-3, which correlated viral load with the host immune response. All these results together; clearly imply that bmnpv-miR-3-mediated controlled regulation of BmNPV late genes in the early stage of infection helps BmNPV to escape the early immune response from the host.


Subject(s)
Bombyx/virology , Gene Expression Regulation, Viral , MicroRNAs/metabolism , Nucleopolyhedroviruses/physiology , RNA, Viral/metabolism , Viral Proteins/genetics , Animals , Bombyx/physiology , Host-Pathogen Interactions , MicroRNAs/genetics , Nucleopolyhedroviruses/genetics , RNA, Viral/genetics , Transcription, Genetic , Viral Proteins/metabolism
9.
Cell Microbiol ; 16(9): 1354-65, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24628957

ABSTRACT

Lepidopterans as other insects have a very potent innate immune system, which basically comprises cellular and humoral defence mechanisms against bacterial and fungal infections. In lepidopterans, not much is known about the defence mechanisms against viral pathogens, such as baculoviruses. Here we show that small silk proteins of the domesticated silkworm, Bombyx mori, called seroins, act as antiviral agents against a baculovirus pathogen, Bombyx mori nucleopolyhedrovirus (BmNPV). Involvement of these proteins in the inhibition of baculovirus infection was revealed by estimating the viral load upon their dsRNA-mediated knockdown. Additionally, we found through antimicrobial assays that seroins are potent inhibitors of bacterial growth. Binding competition assays followed by antimicrobial assays showed that seroins bind to peptidoglycan, a cell wall component of bacteria. Analysis of bacterial load upon knockdown of seroins resulted in higher proliferation of bacteria. Phylogenetic analysis showed the recent origin of seroins in a few moth species and duplication only in Bombycids. The antiviral and antibacterial activity of seroins shown in this study using several biochemical and molecular biological assays provide strong evidence to characterize them as antimicrobial proteins. Hence, we hypothesize that seroins are potent candidates for use in development of transgene-based disease resistant silkworm strains.


Subject(s)
Anti-Bacterial Agents/metabolism , Antiviral Agents/metabolism , Bombyx/metabolism , Animals , Anti-Bacterial Agents/pharmacology , Antiviral Agents/pharmacology , Gram-Positive Bacteria/drug effects , Insect Proteins/metabolism , Insect Proteins/pharmacology , Nucleopolyhedroviruses/drug effects , Peptidoglycan/chemistry , Phylogeny
10.
Protoplasma ; 251(5): 1255-61, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24452725

ABSTRACT

Floral malformation is the most destructive disease in mangoes. To date, the etiology of this disease has not been resolved. There are indications that stress-stimulated ethylene production might be responsible for the disease. Putrescine mediates various physiological processes for normal functioning and cellular metabolism. Here, the effect of putrescine in concentration ranging from 10(-1) to 10(-3) M was evaluated on disease incidence during mango flowering seasons of 2012 and 2013. In a scanning electron microscopy (SEM) study, putrescine (10(-2) M)-treated malformed floral buds bloomed into opened flowers with separated sepals and/or petals like healthy, whereas the untreated (control) malformed buds remained deformed. Further, malformed flowers recovered upon putrescine treatment, displaying clearly bilobed anthers, enclosing a large number of normal pollen grains and functional ovary with broad stigmatic surface as compared to control. The present findings provide the first report to demonstrate the role of putrescine in reducing various adverse effects of stress ethylene via decelerating the higher pace of its biosynthesis. It stabilizes the normal morphology, development, and functions of malformed reproductive organs to facilitate successful pollination, fertilization, and, thereby, fruit set in mango flowers. However, putrescine-ethylene-mediated cell signaling network, involving various genes to trigger the response, which regulates a wide range of developmental and physiological processes leading to normal cell physiology, needs to be investigated further.


Subject(s)
Flowers/growth & development , Mangifera/growth & development , Putrescine/metabolism , Stress, Physiological/drug effects , Ethylenes/metabolism , Flowers/drug effects , Fruit/growth & development , Mangifera/drug effects , Microscopy, Electron, Scanning , Plant Diseases , Putrescine/pharmacology
11.
J Environ Biol ; 34(4): 789-92, 2013 Jul.
Article in English | MEDLINE | ID: mdl-24640258

ABSTRACT

A comparative study was conducted for the food items and feeding pattern of Channa punctatus in pond environment and in reservoir of Tarai region in Uttarakhand state. Observation was made for body length, gut length, food and feeding frequency and qualitative and quantitative analysis of gut content. Both, body length and gut length were in higher side with a ratio of 1:2.1 for the natural fish stock of reservoir. Gut content mainly consists of crustacean, insects, mollusks, small fishes and semi-digested material. There was significant difference for the percent occurrence of the food items (p < 0.01) of natural stock of reservoir and pond reared stock. The study revealed that seasonal variability of natural food items in different habitats and their biological diversity put impacts on the biological needs in terms of food and feeding pattern of the same fish species.


Subject(s)
Ecosystem , Feeding Behavior/physiology , Fishes/physiology , Animals , India
12.
J Nanosci Nanotechnol ; 12(6): 4644-9, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22905511

ABSTRACT

We present synthesis of silicon nanoparticles dispersed in toluene by laser ablation and studies on their optical limiting properties with nanosecond laser pulses at 532 nm. Silicon nanoparticles in toluene show better optical limiting compared to standard optical limiter fullerene C60 in toluene. Optical limiting threshold of silicon nanoparticles is about three times less than that of C60. Detailed studies using Z-scan experiments, angle dependent scattering, intensity dependent transmission and temporal profile measurements indicate that apart from non-linear scattering, nonlinear absorption and nonlinear refraction also contribute to the optical limiting behavior of silicon nanoparticles.


Subject(s)
Nanostructures/chemistry , Nanostructures/ultrastructure , Silicon/chemistry , Silicon/radiation effects , Lasers , Materials Testing , Nanostructures/radiation effects , Particle Size , Refractometry
13.
J Virol ; 86(15): 7867-79, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22593162

ABSTRACT

MicroRNAs have emerged as key players in the regulation of various biological processes in eukaryotes, including host-pathogen interactions. Recent studies suggest that viruses encode miRNAs to manipulate their host gene expression to ensure their effective proliferation, whereas the host limits virus infection by differentially expressing miRNAs that target essential viral genes. Here, we demonstrate that an insect virus, Bombyx mori nucleopolyhedrosis virus (BmNPV), modulates the small-RNA-mediated defense of its host, B. mori, by encoding an miRNA (bmnpv-miR-1) that downregulates the expression of the host GTP-binding nuclear protein Ran, an essential component of the exportin-5-mediated nucleocytoplasmic transport machinery mainly involved in small-RNA transport from the nucleus to the cytoplasm. We demonstrate the sequence-dependent interaction of bmnpv-miR-1 with Ran mRNA using cell culture and in vivo assays, including RNA interference (RNAi) of Ran. Our results clearly show that bmnpv-miR-1 represses Ran, leading to reduction in the host small-RNA population, and consequently, the BmNPV load increases in the infected larvae. Blocking of bmnpv-miR-1 resulted in higher expression levels of Ran and a decrease in BmNPV proliferation. In contrast, blockage of host miRNA, bmo-miR-8, which targets the immediate-early gene of the virus and whose production was repressed upon bmnpv-miR-1 and Ran dsRNA administration, resulted in a significant increase in the virus load in the infected B. mori larvae. The present study provides an insight into one of the evasion strategies used by the virus to counter the host defense for its effective proliferation and has relevance to the development of insect virus control strategies.


Subject(s)
Bombyx/virology , Cell Nucleus/metabolism , Insect Proteins/metabolism , MicroRNAs/metabolism , Nucleopolyhedroviruses/metabolism , RNA, Viral/metabolism , ran GTP-Binding Protein/metabolism , Active Transport, Cell Nucleus/physiology , Animals , Bombyx/genetics , Bombyx/metabolism , Cell Nucleus/genetics , Cell Nucleus/virology , Insect Proteins/genetics , Karyopherins/genetics , Karyopherins/metabolism , Larva/genetics , Larva/metabolism , Larva/virology , MicroRNAs/genetics , Nucleopolyhedroviruses/genetics , RNA, Viral/genetics , ran GTP-Binding Protein/genetics
14.
Ultrason Sonochem ; 18(5): 923-7, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21489849

ABSTRACT

Ultrasonication used for the production of fatty acid methyl ester from non-edible vegetable oil using immobilized lipase (Chromobacterium viscosum) as a catalyst from Enterobacter aerogenes to make the process fully ecologically and environmental friendly. The optimal conditions for biodiesel production is the molar ratio oil to methanol 1:4, catalyst concentration 5 wt.% of oil, reaction time 30 min, ultrasonic amplitude 50% (100 W/m(3)) and cycle 0.7s. ultrasonication reduce the reaction time comparing to the conventional batch process. The purity and conversion of the biodiesel was 84.5±0.5 analyzed by reversed phase HPLC.


Subject(s)
Esterification/radiation effects , Jatropha/chemistry , Lipase/chemistry , Lipase/radiation effects , Plant Oils/chemistry , Plant Oils/radiation effects , Sonication/methods , Radiation Dosage
15.
Faraday Discuss ; 153: 61-72; discussion 73-91, 2011.
Article in English | MEDLINE | ID: mdl-22452074

ABSTRACT

We report an investigation to elucidate the mechanisms of control in phase-sensitive experiments in two molecular systems. A first inspection of optimization procedures yields the same experimental result: increase in the emission efficiency upon excitation by a phase modulated pulse in a two-photon transition. More detailed studies, which include power dependence, spectral response, one and two color pump-probe and pump-pump experiments show that while for one chromophore phase modulation leads to spectral matching between the two-photon cross section and the second order power spectrum for the other it provides a tool to manipulate the wavepacket dynamics in the excited state.


Subject(s)
Luminescence , Rhodamines/chemistry , Dendrimers/chemistry , Photons , Quantum Theory
16.
Virology ; 407(1): 120-8, 2010 Nov 10.
Article in English | MEDLINE | ID: mdl-20800868

ABSTRACT

MicroRNAs (miRNAs) have emerged as key players in host-pathogen interaction. Recently, many virus-encoded miRNAs have been identified from different mammalian species. However, the large family of invertebrate viruses of Baculoviridae, which infects diverse species of beneficial insects and agriculture pests, has hardly been investigated for elucidating the role of miRNAs in host-pathogen interaction. In the study reported here, we have identified four Bombyx mori nucleopolyhedrosis virus (BmNPV)-encoded miRNAs using a combination of in silico and experimental methods. Unlike other reported viral miRNAs, the BmNPV-encoded miRNAs identified in the present study were found to be evolutionarily conserved among many closely related baculoviruses. Besides, we have computationally predicted 8 viral and 64 cellular targets of these virus-encoded miRNAs and the putative functions of these targets suggest a key role of viral miRNAs in insect-pathogen interactions by modulating several viral replication genes as well as those involved in host immune defense machinery.


Subject(s)
Bombyx/virology , MicroRNAs/genetics , Nucleopolyhedroviruses/genetics , Animals , Conserved Sequence , Host-Pathogen Interactions , MicroRNAs/metabolism , Models, Molecular , Nucleic Acid Conformation , Nucleopolyhedroviruses/isolation & purification , Nucleopolyhedroviruses/physiology , Phylogeny , Sequence Homology, Nucleic Acid
17.
Bioresour Technol ; 2010 Aug 06.
Article in English | MEDLINE | ID: mdl-20801025

ABSTRACT

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

18.
Eur J Med Chem ; 45(7): 3056-62, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20403649

ABSTRACT

M(II) complexes of the type [HLCu(2)Cl(3)], [HLCu(2)(O(CO)CH(3))(3)], [HLM(2)Cl(4)(H(2)O)(3)] and [HLM(2)(OC(O)CH(3))(4)(H(2)O)(3)], where M=Ni(II), Co(II) have been synthesized by condensation of 3-acyl-2-one indol and hydrazinecarbothioamide (2:1) in the presence of divalent metal salt in methanolic medium. The complexes have been characterized with the help of elemental analysis, conductance measurements, magnetic measurements and their structural configuration have been determined by various spectroscopic (electronic, IR, (1)H NMR, (13)C NMR, GCMS) techniques. Electronic and magnetic moments of the complexes indicate that the geometries of the metal centers are either distorted octahedral, or square planer. These metal complexes were also tested for their antibacterial and antifungal activities to assess their inhibiting potential.


Subject(s)
Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/pharmacology , Organometallic Compounds/chemical synthesis , Organometallic Compounds/pharmacology , Schiff Bases/chemistry , Anti-Infective Agents/chemistry , Bacteria/drug effects , Cobalt/chemistry , Copper/chemistry , Electrons , Fungi/drug effects , Magnetics , Microbial Sensitivity Tests , Nickel/chemistry , Organometallic Compounds/chemistry , Spectrum Analysis
19.
Ultrason Sonochem ; 17(5): 839-44, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20359932

ABSTRACT

The production of biodiesel from non-edible vegetable oil using ultrasonication, calls for an efficient solid catalyst to make the process fully ecologically and economically friendly. The methodology allows for the reaction to be run under atmospheric conditions. Solid catalyst and ultrasonication reduced the reaction time comparing to the conventional batch processes and we found 98.53% biodiesel yield. The optimal conditions for biodiesel production is the molar ratio oil to methanol 1:9, Catalyst conc. 3 wt.% of oil and 15 min reaction time.


Subject(s)
Jatropha/chemistry , Jatropha/radiation effects , Plant Oils/chemical synthesis , Plant Oils/radiation effects , Silicon Dioxide/chemistry , Sodium/chemistry , Sonication , Catalysis , Esters/chemistry , Esters/radiation effects , Silicon Dioxide/radiation effects , Sodium/radiation effects
20.
Ultrason Sonochem ; 17(3): 555-9, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19945331

ABSTRACT

Biodiesel is a renewable fuel, consistituting an alternative to petroleum-based diesel fuel. It is non-toxic and biodegradable and has a low emission profile, is better from environmentally sensitive areas. Research study on alternative fuels is essential for increased energy security. Presently, biodiesel is produced mainly is batch reactor. In this process the required energy is given by heating accompanied by mechanical stirring which has several disadvantages because of time consuming high labour cost. Being methanol is a toxic chemical; the objective of this work is to produce coconut oil ethyl ester by using ultrasonic irradiation. The advantages of ethanol are non-toxic domestic all available, having higher carbon atoms which provide higher heat content. The optical conditions for biodiesel production is the molar ratio oil to ethanol 1:6, KOH catalyst 0.75wt.% of oil and 7min reaction time. The reaction time reduced 15-40 times comparing to the conventional batch processes and found >or=98% biodiesel yield.


Subject(s)
Biofuels , Ethanol/chemistry , Plant Oils/chemistry , Sonication , Catalysis , Coconut Oil , Esterification , Glycerol/chemistry , Hydroxides/chemistry , Kinetics , Potassium Compounds/chemistry
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