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1.
Parasitol Res ; 119(9): 2955-2963, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32647992

RESUMO

Equine piroplasmosis (EP) is an infectious, tick-borne disease caused by the hemoprotozoan parasites, Theileria equi, Babesia caballi, and a recently reported new species, T. haneyi. Infections by these apicomplexan parasites limit performance and cause economic losses for the horse industry. Equine piroplasmosis is widespread in the northern regions of Nigeria, where an increasing portion of the animal population is composed of horses. This disease has remained epidemiologically challenging, especially as the movement of horses increases across Nigeria. In this study, blood samples from 300 horses were collected in three states of northwestern Nigeria. The presence of piroplasms was screened by nested PCR targeting 18S rDNA and positive samples were analyzed using species-specific-nested PCR-targeting genes including ema1 (T. equi), rap1 (B. caballi), and a gene coding a protein of unknown function (T. haneyi). Species-specific-nPCR results demonstrated that the prevalence of T. equi was 13.0% (39/300), B. caballi was 3.3% (10/300) and T. haneyi was 2.7% (8/300). Mixed infections with T. equi and B. caballi was 2.7% (8/300) while T. equi, B. caballi, and T. haneyi multiple infection prevalence was 0.6% (2/300). We used 18S rDNA sequences to determine close relationships between T. equi by phylogenetic analysis and demonstrated that among 57 sequences of Theileria parasites, 28 samples belonged to clade A (49%), 13 samples were found to be clade C (22%), and 16 were clade D (28%). These results demonstrate the genetic diversity of T. equi circulating in horses from Nigeria.


Assuntos
Babesiose/diagnóstico , Doenças dos Cavalos/diagnóstico , Cavalos/parasitologia , Reação em Cadeia da Polimerase/veterinária , Theileriose/diagnóstico , Animais , Babesia/genética , Babesia/isolamento & purificação , Babesiose/epidemiologia , Babesiose/parasitologia , Bovinos , Doenças dos Cavalos/parasitologia , Nigéria/epidemiologia , Filogenia , RNA Ribossômico 18S/genética , Theileria/genética , Theileria/isolamento & purificação , Theileriose/epidemiologia , Theileriose/parasitologia , Doenças Transmitidas por Carrapatos/epidemiologia
2.
Appl Biochem Biotechnol ; 192(2): 585-599, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32495234

RESUMO

Strategies to immobilize the individual enzymes are crucial for enhancing catalytic applicability and require a controlled immobilization process. Herein, protocol for immobilizing Candida rugosa lipase (CRL) onto modified magnetic silica derived from oil palm leaves ash (OPLA) was optimized for the effects of concentration of CRL, immobilization time, and temperature, monitored by titrimetric and spectrometric methods. XRD and TGA-DTG spectrometric observations indicated that OPLA-silica was well coated over magnetite (SiO2-MNPs) and CRLs were uniformly bound by covalent bonds to SiO2-MNPs (CRL/Gl-A-SiO2-MNPs). The optimized immobilization protocol showed that in the preparation of CRL/Gl-A-SiO2-MNPs, CRL with 68.3 mg/g protein loading and 74.6 U/g specific activity was achieved using 5 mg/mL of CRL, with an immobilization time of 12 h at 25 °C. The present work also demonstrated that acid-pretreated OPLA is a potential source of renewable silica, envisioning its applicability for practical use in enzymatic catalysis on solid support.


Assuntos
Arecaceae/química , Enzimas Imobilizadas/química , Lipase/química , Nanoestruturas/química , Folhas de Planta/química , Dióxido de Silício/química , Biocatálise , Enzimas Imobilizadas/metabolismo , Cinética , Lipase/metabolismo , Temperatura
3.
J Biotechnol ; 283: 81-96, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30063951

RESUMO

The study reports the preparation of a composite consisting of magnetite coated with nanosilica extracted from oil palm leaves (OPL) ash as nanosupports for immobilization of Candida rugosa lipase (CRL) and its application for the synthesis of butyl butyrate. Results of immobilization parameters showed that ∼ 80% of CRL (84.5 mg) initially offered was immobilized onto the surface of the nanosupports to yield a maximum protein loading and specific activity of 67.5 ± 0.72 mg/g and 320.8 ± 0.42 U/g of support, respectively. Surface topography, morphology as well as information on surface composition obtained by Raman spectroscopy, atomic force microscopy, field emission scanning electron microscopy and transmission electron microscopy showed that CRL was successfully immobilized onto the nanosupports, affirming its biocompatibility. Under optimal conditions (3.5 mg/mL protein loading, at 45 ℃, 3 h and molar ratio 2:1 (1-butanol:n-butyric acid) the CRL/Gl-A-SiO2-MNPs gave a maximum yield of 94 ± 0.24% butyl butyrate as compared to 84 ± 0.32% in the lyophilized CRL. CRL/Gl-A-SiO2-MNPs showed an extended operational stability, retaining 50% of its initial activity after 17 consecutive esterification cycles. The results indicated that OPL derived nanosilica coated on magnetite can potentially be employed as carrier for lipase immobilization in replacement of the non-renewable conventionalsilica sources.


Assuntos
Enzimas Imobilizadas/metabolismo , Lipase/metabolismo , Óleo de Palmeira/química , Dióxido de Silício/isolamento & purificação , Biocatálise , Candida/enzimologia , Estabilidade Enzimática , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Lipase/química , Modelos Moleculares , Folhas de Planta/química , Dióxido de Silício/química , Propriedades de Superfície
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