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2.
3 Biotech ; 6(2): 216, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28330288

RESUMO

Biosynthesis of plant-mediated silver nanoparticles is gaining significant importance due to environmentally safe 'green method' and it is an efficient alternative method. In the present study, silver nanoparticles were synthesized by using root extract of Glycyrrhiza glabra an important medicinal plant. The AgNPs are characterized by spectral analysis; the surface plasmon resonance (SPR) peak of AgNPs showed maximum absorption at 445 nm. Fourier-transform infrared spectroscopy (FT-IR) data show that the O-H hydroxyl groups, carboxylic acids, ester and ether groups and C-O stretching of alcohols have been utilized in the formation of AgNPs. The X-ray powder diffraction (XRD) data reveal that the AgNPs are face-centered cubic (fcc) in structure. The size was determined by particle size analyzer and atomic force microscope (AFM); the results reveal that AgNPs were spherical in shape and the average grain size is determined as 41.5-46.5 nm. Transmission electron microscopy (TEM) micrographs obtained show that AgNPs were roughly spherical and well dispersed with the sizes ranging from 10 to 45 nm ± 5 nm. The biofabricated AgNPs are extremely stable due to its high negative zeta potential -34.1 mV which indicates that the nanoparticles are polydispered in nature. The cytotoxic studies of AgNPs on human CD34 +ve stem cells in microcarrier culture reveal excellent growth at different concentrations of biosynthesized AgNPs. This is the first report of microcarrier culture of CD34 +ve stem cells on biosynthesized AgNPs.

3.
J Virol Methods ; 203: 9-14, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24675064

RESUMO

Citrus yellow mosaic badnavirus (CMBV) is an important pathogen in southern India spread by infected citrus propagules. One of the measures to arrest the spread of CMBV is to develop methods to screen and certify citrus propagules as CMBV-free. The methods loop-mediated isothermal amplification (LAMP) and SYBR green real-time PCR (SGRTPCR) have been developed for the efficient detection of CMBV in citrus propagules. This paper compares the sensitivities of LAMP and SGRTPCR with polymerase chain reaction (PCR) for the detection of CMBV. Whereas PCR and LAMP were able to detect CMBV from a minimum of 10 ng of total DNA of infected leaf samples, SGRTPCR could detect the same from 1 ng of total DNA. Using SGRTPCR, the viral titres were estimated to be the highest in rough lemon and lowest in Nagpur Mandarin of the five naturally infected citrus species tested. The results will help in designing suitable strategies for the sensitive detection of CMBV from citrus propagules.


Assuntos
Badnavirus/isolamento & purificação , Citrus/virologia , Técnicas de Amplificação de Ácido Nucleico/métodos , Badnavirus/genética , Índia , Compostos Orgânicos/metabolismo , Doenças das Plantas/virologia , Sensibilidade e Especificidade , Coloração e Rotulagem/métodos , Temperatura
4.
Eur J Med Chem ; 73: 135-40, 2014 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-24389508

RESUMO

New and novel strategies are of recent interest in the development of silver nanoparticles. The plant extracts are eco-friendly, economical and cost effective for synthesis of nanoparticles. In this paper, we represent biofabrication of silver nanoparticles (AgNPs) using Andrographis paniculata and the synthesized AgNPs was monitored by ultra-violet visible spectroscopy (UV-Vis). The morphology and crystalline nature of AgNPs were determined from scanning electron microscopy (SEM) with Energy dispersive X-ray (EDX), X-ray diffraction patterns (XRD), Fourier transform-infrared spectroscopy (FT-IR). The size and the stability were detected by using Nanoparticle analyzer. The average size of the AgNPs was found to be 54 ± 2 nm and the Zeta potential was found to be -50.7 mV. The synthesized AgNPs have very good antifungal activity.


Assuntos
Andrographis/química , Antifúngicos/síntese química , Desenho de Fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Prata/química , Antifúngicos/química , Aspergillus niger/efeitos dos fármacos , Estabilidade de Medicamentos , Microscopia Eletrônica de Varredura , Oxirredução , Tamanho da Partícula , Penicillium/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Espectrofotometria Ultravioleta , Propriedades de Superfície , Difração de Raios X
5.
J Pathog ; 2013: 424123, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23738078

RESUMO

Shrimp farming is an aquaculture business for the cultivation of marine shrimps or prawns for human consumption and is now considered as a major economic and food production sector as it is an increasingly important source of protein available for human consumption. Intensification of shrimp farming had led to the development of a number of diseases, which resulted in the excessive use of antimicrobial agents, which is finally responsible for many adverse effects. Currently, probiotics are chosen as the best alternatives to these antimicrobial agents and they act as natural immune enhancers, which provoke the disease resistance in shrimp farm. Viral diseases stand as the major constraint causing an enormous loss in the production in shrimp farms. Probiotics besides being beneficial bacteria also possess antiviral activity. Exploitation of these probiotics in treatment and prevention of viral diseases in shrimp aquaculture is a novel and efficient method. This review discusses the benefits of probiotics and their criteria for selection in shrimp aquaculture and their role in immune power enhancement towards viral diseases.

6.
Indian J Virol ; 24(2): 289-90, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24426289

RESUMO

A field visit in September 2011 to the Cucumis anguira (Gherkin) growing regions of Kuppam, Chittoor district of Andhra Pradesh, India revealed occurrence of mosaic, blistering and fruit malformation leading to the crop losses. Analysis of field samples revealed association of Zucchini yellow mosaic virus (ZYMV) with the disease. This is the first confirmed report of natural occurrence of ZYMV on Gherkin in India.

7.
Artigo em Inglês | MEDLINE | ID: mdl-23257344

RESUMO

A simple method for the green synthesis of silver nanoparticles (AgNPs) using aqueous extract of Lakshmi tulasi (Ocimum sanctum) leaf as a reducing and stabilizing agent. AgNPs were rapidly synthesized using aqueous extract of tulasi leaf with AgNO(3) solution within 15 min. The green synthesized AgNPs were characterized using physic-chemical techniques viz., UV-Vis, X-ray diffraction (XRD), scanning electron microscope (SEM) coupled with X-ray energy dispersive spectroscopy (EDX) and Fourier transform-infrared spectroscopy (FT-IR). Characterization data reveals that the particles were crystalline in nature and triangle shaped with an average size of 42 nm. The zeta potential of AgNPs were found to be -55.0 mV. This large negative zeta potential value indicates repulsion among AgNPs and their dispersion stability.


Assuntos
Química Verde/métodos , Nanopartículas Metálicas/química , Ocimum/química , Extratos Vegetais/química , Folhas de Planta/química , Prata/química , Química Verde/economia , Nanopartículas Metálicas/ultraestrutura , Oxirredução , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
8.
Virus Genes ; 45(3): 600-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22926812

RESUMO

Citrus yellow mosaic badna virus (CMBV), a member of the Family Caulimoviridae, Genus Badnavirus is the causative agent of mosaic disease among Citrus species in southern India. Despite its reported prevalence in several citrus species, complete information on clear functional genomics or functional information of full-length genomes from all the CMBV isolates infecting citrus species are not available in publicly accessible databases. CMBV isolates from Rough Lemon and Sweet Orange collected from a nursery were cloned and sequenced. The analysis revealed high sequence homology of the two CMBV isolates with previously reported CMBV sequences implying that they represent new variants. Based on computational analysis of the predicted secondary structures, the possible functions of some CMBV proteins have been analyzed.


Assuntos
Badnavirus/genética , Citrus sinensis/virologia , Genoma Viral , Doenças das Plantas/virologia , Sequência de Aminoácidos , Badnavirus/classificação , Badnavirus/isolamento & purificação , Badnavirus/patogenicidade , Clonagem Molecular , Biologia Computacional , Sequência Consenso , DNA Viral/genética , Bases de Dados Genéticas , Índia , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Estrutura Secundária de Proteína , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
9.
Indian J Virol ; 23(1): 80-2, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23730009

RESUMO

The natural occurrence of Tobacco streak virus (TSV) in Hibiscus cannabinus was detected by enzyme-linked immunosorbent assay using an antiserum raised against TSV and reverse transcription polymerase chain reaction (PCR) using primers specific for the coat protein gene of the virus. Sequence analysis of the PCR products showed 99.6 and 99.5% of maximum identity at nucleotide and amino acid levels, respectively with TSV onion isolate from Kurnool (HM131490).This is the first report of the natural occurrence of TSV on kenaf in India.

10.
Indian J Microbiol ; 50(2): 221-4, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23100832

RESUMO

A virus associated with severe mosaic disease of gherkin (Cucumis anguria L.) in south India was identified. The infected plants showed mosaic, vein banding, blistering on malformed leaves and fruits. Host range, transmission, serological and electron microscopic studies were carried out to identify the virus. The virus was readily transmitted by Sap inoculation and by aphids in a non-persistent manner. The host range of the virus was mainly limited to cucurbitaceous and chenopodium species. The virus showed positive serological relationships with members of potyvirus genus but not with cucumo, ilar and taspoviruses. Electron microscopy of leaf dip preparation of infected leaves revealed long flexuous filamentous virus particles measuring 750 × 12 nm. On the basis of symptomotology, host range, transmission, serology and particle morphology the virus associated with mosaic disease of gherkin might be the member of potyvirus genus.

11.
Indian J Virol ; 21(1): 8-17, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23637474

RESUMO

Chikungunya virus (CHIKV), a reemerging arboviral disease of public health concern is characterized by a triad of fever, rash and arthralgia. It was responsible for a number of epidemics in Asia and Africa. The severity of the current epidemic can be judged by the fact that an estimated 1.38 million people in India and one-third of the La Reunion population (by April 2006) were affected by CHIKV. Aedes aegypti and Aedes albopictus are the major mosquitoes transmitting CHIKV in Asia. Various neurological complications and CHIKV associated deaths were encountered during the current outbreak (2005-2010). The aggressive nature of the recent CHIKV epidemic was attributed to the mutations in the viral genome in addition to their adaptation and spread to vectors like Aedes albopictus. Proper diet, adequate rest and symptomatic treatment using non-salicylate analgesics and Non-steroidal anti inflammatory drugs (NSAIDS) helped the patients in recovering from CHIKV infections. In the absence of an effective vaccine, rapid implementation of mosquito control measures and establishment of a system for continuous surveillance of the disease seems to be the only possible solution to prevent any such outbreak in the near future.

12.
Virus Genes ; 39(1): 137-40, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19444599

RESUMO

Citrus yellow mosaic badna virus (CMBV), a member of the Family Caulimoviridae, Genus Badnavirus, is the causative agent of Citrus mosaic disease in India. Although the virus has been detected in several citrus species, only two full-length genomes, one each from Sweet orange and Rangpur lime, are available in publicly accessible databases. In order to obtain a better understanding of the genetic variability of the virus in other citrus mosaic-affected citrus species, we performed the cloning and sequence analysis of complete genomes of CMBV from two additional citrus species, Acid lime and Pummelo. We show that CMBV genomes from the two hosts share high homology with previously reported CMBV sequences and hence conclude that the new isolates represent variants of the virus present in these species. Based on in silico sequence analysis, we predict the possible function of the protein encoded by one of the five ORFs.


Assuntos
Badnavirus/genética , Badnavirus/isolamento & purificação , Citrus aurantiifolia/virologia , Citrus/virologia , DNA Viral/genética , Genoma Viral , Análise de Sequência de DNA , Sequência de Aminoácidos , Badnavirus/classificação , DNA Viral/química , Índia , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência , Proteínas Virais/genética
13.
J Virol Methods ; 151(2): 321-4, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18582956

RESUMO

Nucleic acid preparations extracted using four procedures were assessed to determine the suitability of the procedure for PCR-based and DNA dot-blot-based detection of Citrus yellow mosaic badna virus (CMBV) from two citrus species, acid lime and pummelo. It was found that the success of PCR detection depended upon the procedure of DNA extraction whereas the dot-blot detection was successful with all extraction methods examined. CMBV DNA sequences amplified from two citrus species indicated high nucleotide sequence identity to the sequences reported previously from sweet orange. These results will help in choosing the correct DNA extraction procedure to be followed for efficient virus screening of citrus propagules.


Assuntos
Caulimovirus/genética , Citrus/virologia , DNA Viral/genética , DNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Caulimovirus/classificação , Caulimovirus/isolamento & purificação , Primers do DNA , Hibridização de Ácido Nucleico , Filogenia
14.
Plant Dis ; 84(12): 1343, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30831882

RESUMO

Virus-like symptoms were observed on sunflower in and around Tirupati during January 1998. Infected plants exhibited severe mosaic, systemic necrosis along the stem and floral heads, leaf distortion, and ringspots on leaves. The causal virus, mechanically transmissible from sunflower to sunflower cvs. Morden, MHSF8, MHSF18, KBHS1, and Cargil, developed symptoms like those in the original plant. The virus caused chlorotic and necrotic spots on Chenopodium amaranticolor, chlorotic and necrotic rings on cowpea cv. C-152, chlorotic spots on Datura metal and Petunia hybrida, chlorotic rings and systemic infection on Gomphrena globosa, tarlike symptoms on Catharanthus roseus, and local brown lesions on Cassia tora (1). Virus was isolated from infected sunflower leaves (2), and particles in negatively stained preparations were enveloped and 80 to 90 nm in diameter. Cytopathic effects included accumulation of virus particles in the endoplasmic reticulum, the formation of viroplasm, and aggregates consisting of nonenveloped viral nucleocapsids in the cytoplasm of ultrathin sections of infected sunflower leaves. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of capsid protein resolved as a single band of 31 kD. The dsRNA isolated from infected sunflower leaves resolved as three bands of 9, 4.9, and 3 kb in 2% agarose gel electrophoresis. In enzyme-linked immunosorbent assay, the purified virus reacted with homologous and Peanut bud necrosis virus (PBNV-ICRISAT, India) antisera and not to polyclonal antibodies to Iris yellow spot virus (Netherlands), Tomato spotted wilt virus-T (Georgia), Impatiens necrotic spot virus, and several isolates of Cucumber mosaic virus (CMV-B, CMV-C, CMV-To). In western blotting analysis, the virus coat protein reacted with homologous and PBNV antisera corresponding to coat protein band of 31 kD. In reverse transcription polymerase chain reaction, the viral RNA was amplified by using primers derived from NP gene sequence of PBNV and Watermelon silver mottle virus (WSMV). Based on these properties, the virus causing sunflower mosaic followed by necrosis in India was identified as a tospovirus, which may be as a distinct isolate of sero group IV. References: (1) A. A. Brunt et al. Viruses of Plants Online. 1996. Australian National University, Canberra, 1996. (2) D. V. R. Reddy et al. Bud necrosis virus: A disease of peanut caused by Tomato spotted wilt virus. ICRISAT Inf. Bull. No. 31, 1991.

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