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3.
Int J Biol Macromol ; 197: 179-200, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34968542

RESUMO

The pulp and biorefining industries produce their waste as lignin, which is one of the most abundant renewable resources. So far, lignin has been remained severely underutilized and generally burnt in a boiler as a low-value fuel. To demonstrate lignin's potential as a value-added product, we will review market opportunities for lignin related applications by utilizing the thermo-chemical/biological depolymerization strategies (with or without catalysts) and their comparative evaluation. The application of lignin and its derived aromatics in various sectors such as cement industry, bitumen modifier, energy materials, agriculture, nanocomposite, biomedical, H2 source, biosensor and bioimaging have been summarized. This comprehensive review article also highlights the technical, economic, environmental, and socio-economic variable that affect the market value of lignin-derived by-products. The review shows the importance of lignin, and its derived products are a platform for future bioeconomy and sustainability.


Assuntos
Lignina
4.
Chemosphere ; 268: 129326, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33360003

RESUMO

Lignin is produced as a byproduct in cellulosic biorefinery as well in pulp and paper industries and has the potential for the synthesis of a variety of phenolics chemicals, biodegradable polymers, and high value-added chemicals surrogate to conventional petro-based fuels. Therefore, in this critical review, we emphasize the possible scenario for lignin isolation, transformation into value addition chemicals/materials for the economic viability of current biorefineries. Additionally, this review covers the chemical structure of lignocellulosic biomass/lignin, worldwide availability of lignin and describe various thermochemical (homogeneous/heterogeneous base/acid-catalyzed depolymerization, oxidative, hydrogenolysis etc.) and biotechnological developments for the production of bio-based low molecular weight phenolics, i.e. polyhydroxyalkanoates, vanillin, adipic acid, lipids etc. Besides, some functional chemicals applications, lignin-formaldehyde ion exchange resin, electrochemical and production of few targeted chemicals are also elaborated. Finally, we examine the challenges, opportunities and prospects way forward related to lignin valorization.


Assuntos
Lignina , Poli-Hidroxialcanoatos , Biomassa , Lignina/metabolismo , Oxirredução , Desenvolvimento Sustentável
5.
Bioresour Technol ; 228: 89-98, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28056373

RESUMO

The aim of this study is to find potential utilization practice of rice straw in India from an environmental perspective. Life cycle assessment (LCA) is conducted for four most realistic utilization practices of straw including: (1) incorporation into the field as fertilizer (2) animal fodder (3) electricity (4) biogas. The results show that processing of 1 ton straw to electricity and biogas resulted in net reduction of 1471 and 1023kg CO2 eq., 15.0 and 3.4kg SO2 eq. and 6.7 and 7.1kg C2H6 eq. emissions in global warming, acidification and photochemical oxidation creation potential respectively. Electricity production from straw replaces the coal based electricity and resulted in benefits in most of the environmental impacts whereas use as an animal fodder resulted in eutrophication benefits. The burning of straw is a harmful practice of managing straw in India which can be avoided by utilizing straw for bioenergy.


Assuntos
Oryza/química , Resíduos/análise , Ácidos/química , Agricultura , Animais , Biocombustíveis/análise , Eletricidade , Eutrofização , Fertilizantes/análise , Aquecimento Global , Índia , Oxidantes/química , Processos Fotoquímicos
6.
Adv Hematol ; 2015: 625721, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26576156

RESUMO

Mutation spectrum varies significantly in different parts and different ethnic groups of India. Social factors such as preference to marry within the community and among 1st degree relatives (consanguinity) play an important role in impeding the gene pool of the disease within the community and so in society by and large. The present paper discusses the role of consanguinity in profiling of beta thalassemia mutation, and thus the approach for prenatal screening and prevention based awareness programme. Clinically diagnosed 516 cases of beta thalassemia were screened at molecular level. A detailed clinical Proforma was recorded with the information of origin of the family, ethnicity, and consanguinity. The present study reports that subjects originating from Uttar Pradesh, Uttarakhand, Bihar, and Jharkhand have c.92+5G>C and c.124_127delTTCT mutation as the commonest mutation compared to the subjects hailing from Madhya Pradesh and Chhattisgarh and Nepal where sickle mutation was found more common. In 40 consanguineous unions more common and specific beta mutations with higher rate of homozygosity have been reported. This consanguinity-based data helps not only in deciding target oriented prenatal diagnostic strategies but also in objective based awareness programmes in prevention of thalassemia major birth.

7.
Indian J Exp Biol ; 53(7): 476-83, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26245034

RESUMO

River pollution due to rapid industrialization and anthropogenic activities adversely affects the aquatic organisms, especially fish. Here, we assessed the genotoxicity, mutagenicity and bioaccumulative aspects of tannery effluents in freshwater murrel, Channa punctatus, an inhabitant of river Ganges. Test specimens were collected from three different polluted sites of the river within and nearby Kanpur area during different seasons and blood samples of these specimens were processed for comet assay and micronucleus test as genotoxicity biomarkers. A significantly (P < 0.05) higher micronuclei induction, nuclear abnormalities and % tail DNA was observed in the specimens collected from the polluted sites. Bioaccumulation studies in the muscle (1.202 µg/g) and gill tissues (< 0.300 µg/g) of the specimens revealed the concentration of chromium (core component of tanning industry) above the maximum permissible limits as prescribed by World Health Organization (WHO). The findings of the present analysis indicated contamination of river Ganges with tannery effluents which induce genotoxicity in fish with seasonal variation.


Assuntos
Dano ao DNA , Monitoramento Ambiental/métodos , Perciformes/genética , Rios/química , Poluentes Químicos da Água/análise , Animais , Cromo/análise , Ensaio Cometa , Eritrócitos/metabolismo , Geografia , Brânquias/citologia , Brânquias/metabolismo , Índia , Testes para Micronúcleos , Músculos/metabolismo , Perciformes/sangue , Estações do Ano
8.
Drug Chem Toxicol ; 38(1): 9-15, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24649973

RESUMO

The present study was undertaken to investigate the genotoxicity and mutagenicity of sublethal concentrations of hexavalent chromium (potassium dichromate) in the Indian major carp, Labeo rohita. The 96 h LC50 value of potassium dichromate estimated was 118 mg L(-1) by probit analysis using SPSS (version 16.0) software. Based on 96 h LC50 value, three sublethal test concentrations of potassium dichromate (29.5, 59.0 and 88.5 mg L(-)(1)) were selected and specimens were exposed in vivo to these test concentrations for 96 h. The mutagenic and genotoxic effects of potassium dichromate were evaluated in gill and blood cells using micronucleus (MN) test and comet assay. In general, significant (p < 0.05) effects due to the concentrations and the exposure durations were observed in exposed specimens. The MN induction was highest at 96 h at all the test concentrations in the peripheral blood. A similar trend was observed for the DNA damage, measured in terms of percentage of tail DNA, in erythrocyte and gill cells. The study indicated hazardous effect of the hexavalent chromium to fish and other aquatic organisms and indirectly to human beings.


Assuntos
Cromo/toxicidade , Cyprinidae , Dano ao DNA , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Poluentes Químicos da Água/toxicidade , Animais , Ensaio Cometa , Cyprinidae/sangue , Cyprinidae/genética , Relação Dose-Resposta a Droga , Brânquias/efeitos dos fármacos , Brânquias/patologia , Dose Letal Mediana , Leucócitos/efeitos dos fármacos , Leucócitos/patologia , Testes para Micronúcleos , Microscopia de Fluorescência , Testes de Toxicidade Aguda
9.
Drug Chem Toxicol ; 37(1): 48-54, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23829824

RESUMO

Labeo rohita (rohu) is one of most important of Indian major carps, which is highly ranked among the important freshwater aquaculture species in the world. Heavy metals are major risk factors for aquatic health, which are biomagnified through the food chain. The present study was carried out to investigate the effect of different divalent salts of two heavy metals, such as zinc (ZnCl(2), ZnSO(4) and ZnNO(3)) and cadmium (CdCl(2) and CdSO(4)), in an established fish cell line, RF developed from fin tissue of L. rohita. The RF cell line was used for assessment of heavy metal cytotoxicity through various endpoint assays, including maximum tolerated dose (MTD) determination, 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay, neutral red (NR) uptake assay, and Coomassie brilliant blue (CBB) assay. Results revealed that these heavy metal salts were cytotoxic to the RF cell line at varied concentrations. MTD values were found to be 1.563, 3.125, 6.25, 12.5 and 25 mg/L for CdCl(2), CdSO(4), ZnCl(2), Zn(NO(3))(2) and ZnSO(4), respectively. The half-maximal inhibitory concentration values calculated by MTT, NR and CB assay were 53.83 ± 7.02, 58.03 ± 9.12 and 79.20 ± 15.27 for ZnSO(4), 26.44 ± 7.01, 36.60 ± 7.82 and 155.6 ± 14.75 for Zn(NO(3))(2), 20.26 ± 17.95, 16.94 ± 7.05 and 87.54 ± 7.58 for ZnCl(2), 5.166 ± 0.57, 15 ± 1 and 41.80 ± 8.38 for CdSO(4) and 4.966 ± 0.56, 9.56 ± 1.73 and 20.93 ± 4.47 for CdCl(2). This study establishes the RF cell line as an in vitro tool for assessment and monitoring of heavy metal concentration in the aquatic environment.


Assuntos
Cádmio/toxicidade , Carpas/metabolismo , Monitoramento Ambiental/métodos , Zinco/toxicidade , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Dose Máxima Tolerável , Vermelho Neutro , Corantes de Rosanilina , Sais de Tetrazólio , Tiazóis , Testes de Toxicidade
10.
Gene ; 527(1): 248-58, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23800668

RESUMO

Relationship among the mahseer species (Family: Cyprinidae) has long been debated in fish systematics. Present study concentrates on the nature of the phylogenetic relationship among the five mahseer species using the sequence of major ribosomal DNA (45S rDNA). We have covered rDNA sequence of approximately 5.2 kb per individual, 26.0 kb per species and 130.0 kb as a whole. We also characterized the 45S and 5S rDNA regions with respect to their nucleotide composition. For phylogenetic analyses, nucleotide sequences were divided into four datasets. First and second datasets contained 18S rDNA and ITS1 sequence, whereas third and fourth datasets consisted of ITS2 and complete 18S-ITS1-5.8S-ITS2-28S, respectively. The NJ tree was constructed for all the datasets. The mahseer species under study formed a monophyletic group well separated from the outgroup species. Similarly, the individuals of Neolissochilus hexagonolepis form monophyletic group with Tor species, indicating Neolissochilus as a sister genus of Tor. The findings from the present study provide greater insights into taxonomic status of mahseer, and set the stage for future investigations dealing with phylo-geography, taxonomy, conservation and co-evolution within this interesting and important group of fish.


Assuntos
Cyprinidae/genética , DNA Espaçador Ribossômico/genética , Animais , Sequência de Bases , Conservação dos Recursos Naturais , Cyprinidae/classificação , Variação Genética , Índia , Dados de Sequência Molecular , Filogenia , Sequências Repetitivas de Ácido Nucleico , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie
11.
Fish Physiol Biochem ; 38(2): 469-82, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21691727

RESUMO

The effects of different concentrations of cadmium chloride on the extent of lipid peroxidation (LPO) and alterations in the antioxidant enzyme activities were studied in liver, kidney and gill tissues of freshwater murrel, Channa punctatus. The fish specimens were exposed to 6.7, 13.4 and 20.1 mg l(-1) sublethal concentrations of cadmium chloride and the oxidative stress was assessed after 24, 48, 72 and 96 h post-exposure. The biomarkers selected for the study were thiobarbituric acid reactive substances for assessing the extent of lipid peroxidation and antioxidant defense system such as reduced glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GP(X)), glutathione-S-transferase (GST), catalase (CAT) and superoxide dismutase (SOD) activities. In general, the cadmium exposure elevated the LPO in subject tissues of treated group and modulated the activities of GPx, GST, SOD, CAT, GR and level of GSH after given exposure as compared to the control. All enzymes activities, except CAT (in kidney and gills), and amount of LPO elevated significantly (P < 0.05) in treated group with respect to control in all tissues, while significant difference was not observed between the exposed concentrations and within exposure duration. The results indicated that increase in LPO level and the fluctuation in antioxidant defense system in fish could be due to cadmium-induced increase in the production of reactive oxygen species (ROS). The potential role of these parameters as biomarkers of heavy metal pollution in aquatic system is discussed.


Assuntos
Antioxidantes/metabolismo , Cádmio/metabolismo , Glutationa/metabolismo , Peroxidação de Lipídeos , Perciformes/metabolismo , Animais
12.
Environ Toxicol Pharmacol ; 31(2): 314-22, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21787700

RESUMO

The mutagenic and genotoxic effect of 'Rasayanzine', an atrazine herbicide, was carried out in fish Channa punctatus using micronucleus and single cell gel electrophoresis (SCGE) assays. Three sub-lethal concentrations of the test material viz., SL-I (1/5th LC(50)=∼8.48 mgL(-1)), SL-II (1/8th LC(50)=∼5.30 mgL(-1)) and SL-III (1/10th LC(50)=∼4.24 mgL(-1)) were calculated using LC(50) value and the fish specimens were exposed to these concentrations. Erythrocyte and gill cells were sampled on day 0, 1, 3, 5, 7, 14, 21, 28 and 35 of exposure for assessment of micronuclei induction in blood erythrocytes and DNA damage using SCGE assay in both blood erythrocytes and gill cells. Significant effects (p<0.01) for both concentration and time of exposure were observed in treated fish. Micronuclei induction in erythrocytes was highest (8.4 mgL(-1)) on day 7 of exposure. The highest level of DNA damage in the SCGE was observed in both tissues on day 5 at all concentrations followed by gradual non-linear decline. This study further confirmed that the micronucleus and SCGE assays are useful in determining potential genotoxicity of water pollutants and might be appropriate as part of monitoring program.


Assuntos
Atrazina/toxicidade , Herbicidas/toxicidade , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Perciformes/genética , Poluentes Químicos da Água/toxicidade , Animais , Ensaio Cometa , Eritrócitos/efeitos dos fármacos , Brânquias/efeitos dos fármacos , Testes para Micronúcleos , Testes de Toxicidade Aguda
13.
Food Chem Toxicol ; 47(3): 650-6, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19141310

RESUMO

Chlorpyrifos (CPF) is the single largest selling agrochemical that has been widely detected in surface waters in India. The studies on long-term genotoxic effects of CPF in different tissues of fish using genotoxic biomarkers are limited. Therefore, in the present study DNA damage by CPF in freshwater fish Channapunctatus using micronucleus (MN) and comet assays was investigated. The LC(50) - 96 h of CPF was estimated for the fish in a semi-static system. On this basis of LC(50) value sublethal and nonlethal concentrations were determined. The DNA damage was measured in lymphocytes and gill cells as the percentage of DNA in comet tails and micronuclei were scored in erythrocytes of fishes exposed to above concentrations of CPF. In general, significant effects for both the concentrations and time of exposure were observed in treated fish. It was found that MN induction in the blood was highest on day 14 at 203.0 microg/l of CPF. The highest DNA damage was observed on day 5, followed by a gradual non-linear decline in the lymphocytes and gill cells. The study indicated MN and comet assays to be sensitive and rapid methods to detect mutagenicity and genotoxicity of CPF and other pollutants in fishes.


Assuntos
Clorpirifos/toxicidade , Ensaio Cometa , Testes para Micronúcleos , Mutagênicos/toxicidade , Praguicidas/toxicidade , Animais , Dano ao DNA
14.
Chemosphere ; 71(10): 1823-31, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18359502

RESUMO

Chlorpyrifos (O,O-diethyl O-3,5,6-trichloro-2-pyridylphosphorothioate) is one of the organophosphate pesticides widely used in agricultural practices throughout world and irreversible inhibitor of cholinesterase in all animal species. Limited efforts have been made to study acute genotoxic effects of chlorpyrifos (CPF) in different tissues of fish using genotoxic biomarkers. Therefore, the present investigation was aimed to study the induction of DNA damage by CPF in freshwater teleost fish Channapunctatus using micronucleus assay (MN assay) and alkaline single-cell gel electrophoresis (comet assay). The value of LC(50) - 96 h of CPF was determined as 811.98 microgl(-1) for C. punctatus, in a semi-static system and on the basis of LC(50) value three acute concentrations viz., 203, 406 and 609 microgl(-1) were determined. The fishes were exposed to the different concentrations of CPF for 96 h and samplings were done at regular intervals for assessment of the MN frequencies and DNA damage. In general, significant effects (P<0.01) from both concentrations and time of exposure were observed in exposed fishes. It was found that the micronucleus induction was highest on 96 h at all concentrations in the peripheral blood. Similar trend was observed for the DNA damage measured in terms of the percentage of tail DNA in the lymphocyte and gill cells. This study explored the combined use of micronucleus assay and comet assay for in vivo laboratory studies using fresh water fish for screening the genotoxic potential of xenobiotics.


Assuntos
Clorpirifos/toxicidade , Dano ao DNA , Inseticidas/toxicidade , Mutagênicos/toxicidade , Perciformes , Poluentes Químicos da Água/toxicidade , Animais , Células Cultivadas , Ensaio Cometa , Eritrócitos/efeitos dos fármacos , Água Doce , Brânquias/citologia , Dose Letal Mediana , Linfócitos/efeitos dos fármacos , Testes para Micronúcleos , Testes de Toxicidade Aguda
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