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1.
Ecotoxicol Environ Saf ; 180: 749-755, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31154199

RESUMO

The present study emphasizes on the antimicrobial susceptibility of different bacterial strains isolated from the external body surface of a commonly found zooplanktonic copepod (Heliodiaptomus viduus, Gurney, 1916) inhabiting both in fresh and brackish water bodies of Midnapore (West and East) Districts, West Bengal, India. Out of 62 bacterial isolated strains, 38 isolates were identified as Gram-positive while the remaining 24 isolates were found to be Gram-negative. Antimicrobial properties of all those bacterial strains were determined by Vitek 2 compact system using minimum inhibitory concentration (MIC) values. All isolated bacterial strains had exhibited differential susceptibilities against some selected antibiotics. Field Emission Scanning Electron Microscope (FE-SEM) analysis revealed the considerable association of bacteria on the cuticular body parts of the studied zooplankton. The outcomes of the present research are expected to enable health professionals in identifying two major problems -1) bacterial association with zooplankton which is so far mostly considered as a novel source of food for fish in aquatic ecosystems. 2) Selection of antibiotics as treatment measure because of the pathogenic effects of zooplankton associated bacteria on human being. This unattended arena of research is also supposed to evoke a new dimension not only because of bacteria-zooplankton interactions but also on undertaking of judicious strategies to find out proper ways and means to make the surface water suitable for the utilization by the common peoples (minimising bacterial contamination) in the context of human health and environmental safety.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Copépodes/microbiologia , Microbiologia da Água , Zooplâncton/microbiologia , Animais , Bactérias/classificação , Interações entre Hospedeiro e Microrganismos , Humanos , Índia , Testes de Sensibilidade Microbiana
2.
Heliyon ; 5(5): e01638, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31111110

RESUMO

The process of bioconversion of solid organic wastes through vermicomposting justifies the environmental message for sustainability such as reduce, recycle and reuse of wastes. In the present study, wastes derived from two different types of paper mill sludge (primary and secondary), was used for their bioconversion through the vermicomposting process using an indigenous species of earthworm (Perionyx excavatus). The maturity and stability stage of vermicompost production was assessed using FT-IR, GC-MS and TG analyses. During vermicomposting, different biochemical functional groups present in the wastes have shown differential chemical alteration and turnover as revealed by FT-IR spectroscopy. This study has also confirmed the trend of biodegradation of complex substances like lignin, cellulose, proteins etc. and thereby demonstrates the extent of mineralization. TG spectral analysis had revealed a mass loss of 80% and 71% in vermicompost produced from primary and secondary sludge respectively. GC-MS studies have also shown the presence of several humic acids like octadecanoic acid, heptadecanoic acid etc. in the decomposing substances demonstrating as an indicator of the maturity of products. This was further confirmed by the decrease of humification index which focuses the combined action of both earthworms and microbes in the degradation of organic wastes. The present study has highlighted the role of an indigenous earthworm in converting specific industrial wastes especially by recording the point of maturation using humic acids an indicator of the quality of decomposing of wastes following several instrumental applications.

3.
Zootaxa ; 4425(1): 165-174, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-30313473

RESUMO

Metachromadora (Bradylaimoides) benepapillata, was first discovered from the coastal mangroves of Bangladesh by Timm (1961). This species was later synonymised with Pseudochromadora cazca, which was described from the Brazilian coast by Gerlach (1956). The present paper proposes to update the taxonomic status of the Timm's species as Pseudochromadora benepapillata comb. n. along with its distribution and comparative morphology. The major differences between P. cazca and P. benepapillata are found in the characteristics of the head capsule; length of cephalic sensilla; length and position of somatic setae; shape of amphideal fovea; shape of spicules and gubernaculum; number and morphology of copulatory and postcloacal thorns. The present report on the occurrence of this species along the eastern most coast of India extends its distribution from the eastern part of Bay of Bengal to its western part.


Assuntos
Nematoides , Animais , Bangladesh , Brasil , Gubernáculo , Índia
4.
Biomed Res Int ; 2018: 1073687, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30225245

RESUMO

Mass production of vermicompost using suitable species of earthworms and selecting target organic waste materials has appeared to be a great development in the realm of biotechnological research for the sustainable eco-management. Although, for the bioconversion of organic wastes to vermicompost, suitable earthworm species play major roles, a hoard of bacterial assemblages by virtue of production of different enzymes facilitate the process of vermicomposting. The present study has documented the roles of vermicompost associated bacteria in combating, preventing, and controlling of cancer so as to open a new vista not only in the field of vermitechnology but also on biomedical research. Earthworms' associated bacterial metabolic products having their unique physicochemical excellence have gained importance due to their roles as a facilitator of apoptosis (programed cell death in a MCF-7 cell line). The antioxidant and anticancer activities of ethyl acetate extracts' of vermicompost associated bacterium Bacillus anthracis were undertaken by antioxidant assay which revealed maximum DPPH radical scavenging effect (75.79 ± 5.41%) of the extracts' at 9 00 µg ml-1. Furthermore, the crude extracts obtained from the same bacteria were found to decrease the activity of SOD (superoxide dismutase) with the increase in doses. MTT assay showed potent cytotoxic activity against human breast adenocarcinoma cells (MCF-7) with the IC50 value of 46.64 ± 0.79 µg ml-1. It was further confirmed through Hoechst 33258 staining of nuclear fragmentation assay and DNA fragmentation analysis. Western blotting test has confirmed a downregulation of Akt upon application of crude extracts. Increase of SOD activity along with decrease of Akt level reflects that the mode of action is entirely PI-3K dependent. This study tends to indicate that B. anthracis isolated from vermicompost could be potentially explored for the development of new therapeutic agents, especially against cancer.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Bacillus anthracis , Animais , Antineoplásicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Humanos , Células MCF-7 , Oligoquetos , Esgotos
5.
Ecotoxicol Environ Saf ; 157: 482-490, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29655850

RESUMO

Owing to increasing concern of global climate-change, temperature rise is of great interest which can be primarily evaluated from the seasonal variations in some organisms. Aquatic environment can be extremely stressful to its inhabitants because most of them are poikilothermous. In the present study, attempt was made to evaluate the biological effects of oxidative-stress and adaptive/antioxidant capacities during temperature variations (36-40 °C for 24hrs to 72hrs) in Bellamya bengalensis both in environmental and laboratory conditions by testing some biomarkers like HSP70, catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH) and glutathione reductase (GR). The biomarker potency of the molecules and the anti-oxidative metabolic-network was postulated and extrapolated to find its resemblance to the climate-change associated organismal variations. In a natural and eco-restored environment in the Eastern part of India, 10-20 fold increases in CAT, SOD and HSP70 protein expressions (Western blot results) were noticed in Bellamya paralleling to their increased enzymatic activities (gel zymogram studies) due to the seasonal (summer versus winter) temperature variation. It is evident from the consecutive three years' study that this variation resulted in the unfavorable physico-chemical changes of water quality parameters like dissolved oxygen, biochemical oxygen demand, alkalinity and consequently decreased the animal density in summer. And that was revived due to their higher reproduction-rate in post rainy/winter season when temperature normalizes resulting in a restoration of favorable environment. In laboratory condition, the reduced GR and increased GPx indicated the oxidative damage as evident by higher tissue MDA level following to higher mortality. Changes in SOD and CAT activities suggest activation of physiological mechanism to scavenge the ROS produced during heat stress. However, when mortality increased at different time points (36 °C - 72 h and 38 °C - 72 h), these enzyme activities also decreased as they failed to save the tissues from ROS. The results suggest that temperature variation does alter the active oxygen metabolism by modulating antioxidant enzyme activities, which can be used as biomarker to detect sub-lethal effects of climate change-associated pollution. The parity in environmental and laboratory experimental results may justify this laboratory experiment as model heat-stress experiment and indicate temperature as a universal stressor which alone or in combination with other water parameters initiates a consistent adapting behavior. The Bellamya bengalensis being the highest faunal representative in its habitat may serve as a good bioindicator species.


Assuntos
Adaptação Biológica , Biomarcadores/metabolismo , Monitoramento Ambiental , Temperatura Alta , Moluscos/fisiologia , Estresse Fisiológico , Animais , Análise da Demanda Biológica de Oxigênio , Catalase/metabolismo , Fenômenos Químicos , Mudança Climática , Água Doce , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Concentração de Íons de Hidrogênio , Índia , Estresse Oxidativo , Estações do Ano , Superóxido Dismutase/metabolismo , Temperatura
6.
J Environ Health Sci Eng ; 16(2): 205-212, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30728992

RESUMO

Purpose: Main thrust of the present study is to determine the role of microbes in changing the proportion and turnover of nutrients such as carbon and nitrogen during vermicomposting of paper mill sludge through the assessment of ß-glucosidase and Leucine arylamidase activities. Methods: The change in the ratio of Total Organic Carbon (TOC) and Total Kjeldahl Nitrogen (TKN) during sludge composting using paper mill sludge, cow dung, straw in the ratio of 5:4:1 have been determined alongside observing ß-glucosidase and Leucine arylamidase activities in different phases (0th, 30th and 60th days) of vermicomposting. The present study also assessed the bacterial assemblages in order to predict their role as major producers of these enzymes as estimated by Vitek 2 system. Results: A declining trend of C/N ratio was observed which exhibited significant negative and positive correlations with the activity of ß-glucosidase and Leucine arylamidase respectively. Twenty-four strains were isolated under two genus Bacillus spp. and Lysinibacillus spp. which revealed differential sensitivity towards major carbon and nitrogen turnover mediating enzymes. Conclusion: Change in the activities of carbon and nitrogen turnover enzymes due to microbial growth and proliferation are the mediator for the change in C/N ratio.

7.
Zootaxa ; 4126(4): 577-86, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27395607

RESUMO

A new genus, Cyathoshiva, of free-living marine nematodes from the subfamily Cyatholaiminae (family Cyatholaimidae, order Chromadorida), is described from the Indian coast. The new genus differs from other known Cyatholaiminae genera in having a unique combination of morphological characters: buccal cavity with well-developed dorsal tooth and two subventral teeth, proximally unpaired gubernaculum and non-cup shaped supplements. The type species Cyathoshiva amaleshi gen. n. sp. n. is characterized by having multispiral amphids with 4.5 turns, punctated cuticle with a weak lateral differentiation, a conical tail, three supplements possessing both tubular and setoid parts, and a gubernaculum with a serrated and dentate distal end.


Assuntos
Adenofórios/classificação , Sedimentos Geológicos/parasitologia , Adenofórios/anatomia & histologia , Adenofórios/crescimento & desenvolvimento , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Índia , Masculino , Tamanho do Órgão , Água do Mar/parasitologia
8.
Environ Monit Assess ; 186(12): 8961-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25240497

RESUMO

Expression of the stress biomarkers 70-kDa heat shock proteins (Hsp70) and manganese superoxide dismutase (MnSOD) was measured as the molecular basis of adaptive response against increased experimental temperatures (32-40 °C for a span of 24-72 h) on the fresh water molluscan species, Bellamya bengalensis (Lamark 1882). The experimental snail specimens were collected during summer and winter seasons from two contrasting wetlands: an ecorestored (free from human interference) site (SI) and other experiencing anthropogenic stresses (SII). The mortality rate of the B. bengalensis and the immunoblotting of MnSOD and Hsp70 of their digestive glands were performed at regular intervals during the period of heat stress. The SI provided a lower stress environment based on physicochemical parameters such as pH, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), and alkalinity for the survival of test species, although both sites experienced mortality due to thermal stresses. The parity in protein expressions displayed a uniform mode of adaptive impact to temperature elevations in both field and laboratory exposure. The Hsp70 expression was minimal at lower thermal stress, but increased with a rise in temperature. It is very likely that higher Hsp70 levels are not directly related to survival or adaptation. In contrast, MnSOD levels appeared to be an indicator of adaptive responses vis-a-vis survival of the animals. So, the expression levels of a universal free radical scavenger like MnSOD are recognized as a potential biomarker in a bioindicator species like Bellamya.


Assuntos
Adaptação Fisiológica/fisiologia , Monitoramento Ambiental/métodos , Gastrópodes/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Superóxido Dismutase/metabolismo , Temperatura , Animais , Água Doce , Estações do Ano , Estresse Fisiológico/fisiologia
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