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1.
Molecules ; 26(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34299554

RESUMO

The present work reports the biobleaching effect on OPEFB pulp upon utilisation of extracellular xylano-pectinolytic enzymes simultaneously yielded from Bacillus amyloliquefaciens ADI2. The impacts of different doses, retention times, pH, and temperatures required for the pulp biobleaching process were delineated accordingly. Here, the OPEFB pulp was subjected to pre-treatment with xylano-pectinolytic enzymes generated from the same alkalo-thermotolerant isolate that yielded those of higher quality. Remarkable enhanced outcomes were observed across varying pulp attributes: for example, enzyme-treated pulp treated to chemical bleaching sequence generated improved brightness of 11.25%. This resulted in 11.25% of less chlorine or chemical consumption required for obtaining pulp with optical attributes identical to those generated via typical chemical bleaching processes. Ultimately, the reduced consumption of chlorine would minimise the organochlorine compounds found in an effluent, resulting in a lowered environmental effect of paper-making processes overall as a consequence. This will undoubtedly facilitate such environmentally-friendly technology incorporation in the paper pulp industry of today.


Assuntos
Bacillus amyloliquefaciens/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Frutas/metabolismo , Óleo de Palmeira/metabolismo , Concentração de Íons de Hidrogênio , Papel , Poligalacturonase/metabolismo , Temperatura
2.
Artigo em Inglês | MEDLINE | ID: mdl-31207881

RESUMO

Leptospirosis is a zoonotic disease that has been reported in Malaysia and has been associated with a recent trend of recreational activities among the youth. Thus, efforts such as educational interventions among high-risk populations, especially the youth, are key to increasing public awareness regarding leptospirosis. This paper presents the findings of a pilot study wherein an educational intervention using a gamification intervention method was used to determine changes in leptospirosis knowledge among youth. On this note, students from a public university in Seremban district, Malaysia, were recruited and were asked to complete questionnaires before and after gamification activities. Baseline and immediate post-intervention data on leptospirosis knowledge were obtained. The total knowledge score was calculated, and differences in the mean pre- and post-intervention knowledge score were determined. Of the total 185 questionnaires that were completed at baseline and immediately post-intervention, only 168 that belonged to respondents who had heard of leptospirosis were analysed in this paper. A significant increase in leptospirosis knowledge was observed for the students following health education by gamification (p < 0.01). The results demonstrate the effectiveness of an educational intervention using gamification in improving leptospirosis knowledge among youth and suggest that gamification could become an efficient tool to prevent the disease within university-age demographics.


Assuntos
Jogos Experimentais , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Leptospirose/prevenção & controle , Adolescente , Adulto , Animais , Feminino , Humanos , Malásia , Masculino , Projetos Piloto , Estudantes , Inquéritos e Questionários , Universidades , Adulto Jovem
3.
BMC Vet Res ; 13(1): 248, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28814309

RESUMO

BACKGROUND: The increasing trend of ban on the use of antibiotic growth promoters (AGPs) across the globe in the poultry industry has led to a growing need for alternatives to AGPs. Prebiotic, probiotic and their combination as a synbiotic have been considered as potential alternatives. This study aimed to investigate the effects of a prebiotic (isomaltooligosaccharide, IMO), a probiotic (PrimaLac®), and their combination (synbiotic) on hen performance, biochemical and haematological responses, and relative organ weights from 20 to 52 weeks of age. RESULTS: Supplementation of 1% IMO (PRE), 0.1% PrimaLac® (PRO) and 1% IMO + 0.1% PrimaLac® (SYN) improved (P < 0.05) feed intake and egg production at 20-36 weeks of age; body weight gain, feed conversion ratio and egg mass at 20-36 and 20-52 weeks of age; and egg weight at 20-36, 37-52 and 20-52 weeks of age. Compared to control-fed hens at 20-36 weeks of age, PRO- and SYN-fed hens produced less (P < 0.05) small size eggs while SYN-fed hens produced more large size eggs. From 37 to 52 weeks of age, PRE-, PRO- or SYN-fed hens produced less (P < 0.05) medium size eggs, and more large and extra-large size eggs. PRE, PRO or SYN supplementation decreased (P < 0.05) the serum total cholesterol at 36 weeks of age, and serum low-density lipoprotein (LDL) cholesterol, alanine aminotransferase (ALT) and alkaline phosphatase (ALP) at 36 and 52 weeks of age. At 36 and 52 weeks of age, supplementation of PRE, PRO or SYN increased (P < 0.05) lymphocyte percentage and decreased (P < 0.05) heterophil percentage, leading to a lower heterophil to lymphocyte (H/L) ratio. No significant differences were observed in the relative weights of the heart, liver, ovary, pancreas and spleen of all dietary treatment groups. CONCLUSIONS: Supplementation of PRE, PRO or SYN improved performance, serum total cholesterol, LDL cholesterol, ALT, ALP and H/L ratio of hens from 20 to 52 weeks of age. These results demonstrated the use of PRE, PRO and SYN as alternative feed additives to AGPs for improving the health and productivity of hens, while PRO is the best for commercial layer production to yield maximum profit.


Assuntos
Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais , Prebióticos , Probióticos , Simbióticos , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/sangue , Galinhas/fisiologia , Colesterol/sangue , Ovos/normas , Feminino , Contagem de Leucócitos/veterinária , Tamanho do Órgão
4.
Molecules ; 22(6)2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28538674

RESUMO

The potential ability of a new yeast strain, Pichia kudriavzevii, in the synthesis of zinc oxide nanoparticles (ZnO-NPs) through a green method was explored in this study. The effect of reaction time (12, 24 and 36 h) on the structure of the resulting ZnO nanoparticles was investigated. From the XRD and TEM results, the ZnO-NPs with a hexagonal wurtzite structure and a particle crystal size of ~10-61 nm was formed at different reaction times. Combing XRD, TEM, and PL results, it was revealed that the sample prepared at intermediate duration (24 h) has the most favorable nanosized structure with the lowest defect concentration. The biomedical properties of ZnO-NPs as free radical scavenging activity, cytotoxicity and antibacterial agents were characterized. Biosynthesized ZnO-NPs showed strong DPPH free radical scavenging and a dose dependent toxicity with non-toxic effects on Vero cells for concentrations below 190 µg/mL. Desirable bactericidal activity was shown by the ZnO-NPs on Gram-positive bacteria (Bacillus subtilis, Staphylococcus epidermidis and Staphylococcus aurous) and Gram-negative bacteria (Escherichia coli and Serratia marcescens). A maximum inhibition zone of ~19 mm was observed for Staphylococcus epidermidis at a concentration of 100 µg/mL for sample prepared at 24 h. The results from this study reveal that ZnO-NPs possesses potential for many medical and industrial applications.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Nanopartículas/química , Pichia/efeitos dos fármacos , Óxido de Zinco/química , Testes de Sensibilidade Microbiana
5.
Int Sch Res Notices ; 2017: 7831954, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28523288

RESUMO

Microbial xylanase and pectinase are two extremely valuable enzymes, which have captivated much attention. This can be seen from the increased demand for these enzymes by many industrial sectors. This study investigates the isolation and screening of extracellular xylanopectinolytic enzymes-producing bacteria in a submerged fermentation (SmF). Samples are collected from the compost of empty fruit bunch (EFB) at Biocompost Pilot Plant, located at Biorefinery Plant, Universiti Putra Malaysia. From the experiment, out of 20 isolates, 11 isolates show xylanase or/and pectinase activity, and only one isolate (EFB-11) shows the concurrent activities of xylanase and pectinase. These activities are selected for enzyme production under submerged fermentation (quantitative screening). At the 72nd hour of incubation, xylanase and pectinase show the highest production, which ranges about 42.33 U/mL and 62.17 U/mL (with low amount of cellulase present), supplemented with 2% (w/v) of rice bran as carbon source at incubation temperature level, which is 30°C. Meanwhile, the pH of media is shifted to 8.42, which indicates that EFB-11 isolate is alkalotolerant bacteria and identified as Bacillus subtilis ADI1. This strain proves to have potential in agroindustrial bioconversion and has a promising ability to scale up to an industrial scale.

6.
J Photochem Photobiol B ; 161: 441-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27318600

RESUMO

The use of nontoxic biological compounds in the synthesis of nanomaterials is an economic and eco-friendly approach. The present work was undertaken to develop zinc oxide nanoparticles (ZnO-NPs) by a green method using simple precursor from the solution consisting of zinc acetate and the flower extract of Anchusa italica (A. italica). Effect of annealing temperature on structural and antimicrobial properties was investigated. The crystalline structure of ZnO-NPs was shown using X-ray diffraction (XRD) analysis. Transmission electron microscopy (TEM) results showed that ZnO-NPs are hexagonal in shapes with mean particle size of ~8 and ~14nm at 100°C and 200°C annealing temperatures respectively. The optical band gap was increased from 3.27eV to 3.30eV with the decreasing of the particle size. The antimicrobial activity of ZnO-NPs towards Gram positive (Bacillus megaterium and Stapphylococcus aureus) and Gram negative (Escherichia coli and Salmonella typhimurium) pathogens decreased with the increasing of the heat treating temperature. In vitro cytotoxicity studies on Vero cells, a dose dependent toxicity with non-toxic effect of concentration below 142µg/mL was shown. The results indicated that A. italica is an appropriate reaction media to prepare ZnO-NPs for cosmetic and bio-medical productions.


Assuntos
Anti-Infecciosos/química , Boraginaceae/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Animais , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Boraginaceae/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Flores/química , Flores/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Células Vero , Difração de Raios X
7.
J Food Sci ; 80(8): C1686-95, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26174350

RESUMO

A 16-wk feeding experiment was conducted to investigate the effects of a prebiotic, isomaltooligosaccharide (IMO), a probiotic, PrimaLac®, and their combination as a synbiotic on the chemical compositions of egg yolks and the egg quality of laying hens. One hundred and sixty 16-wk-old Hisex Brown pullets were randomly assigned to 4 dietary treatments: (i) basal diet (control), (ii) basal diet + 1% IMO (PRE), (iii) basal diet + 0.1% PrimaLac® (PRO), and (iv) basal diet + 1% IMO + 0.1% PrimaLac® (SYN). PRE, PRO, or SYN supplementation not only significantly (P < 0.05) decreased the egg yolk cholesterol (24- and 28-wk-old) and total saturated fatty acids (SFA; 28-, 32-, and 36-wk-old), but also significantly (P < 0.05) increased total unsaturated fatty acids (UFA; 28-, 32-, and 36-wk-old), total omega 6 and polyunsaturated fatty acids (PUFA), including linoleic and alpha-linolenic acid levels in the eggs (28-wk-old). However, the total lipids, carotenoids, and tocopherols in the egg yolks were similar among all dietary treatments in the 24-, 28-, 32-, and 36-wk-old hens. Egg quality (Haugh unit, relative weights of the albumen and yolk, specific gravity, shell thickness, and yolk color) was not affected by PRE, PRO, or SYN supplementation. The results indicate that supplementations with IMO and PrimaLac® alone or in combination as a synbiotic might be useful for improving the cholesterol content and modifying the fatty acid compositions of egg yolk without affecting the quality of eggs from laying hens between 24 and 36 wk of age.


Assuntos
Galinhas , Dieta , Gorduras na Dieta/análise , Gema de Ovo/química , Prebióticos , Probióticos , Simbióticos , Ração Animal , Animais , Colesterol/análise , Ovos/análise , Ovos/normas , Ácidos Graxos/análise , Feminino , Humanos , Ácido Linoleico/análise , Ácido alfa-Linolênico/análise
8.
Microb Cell Fact ; 14: 96, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26150120

RESUMO

BACKGROUND: Bacterial biofilms are a preferred mode of growth for many types of microorganisms in their natural environments. The ability of pathogens to integrate within a biofilm is pivotal to their survival. The possibility of biofilm formation in Lactobacillus communities is also important in various industrial and medical settings. Lactobacilli can eliminate the colonization of different pathogenic microorganisms. Alternatively, new opportunities are now arising with the rapidly expanding potential of lactic acid bacteria biofilms as bio-control agents against food-borne pathogens. RESULTS: A new isolate Lactobacillus plantarum PA21 could form a strong biofilm in pure culture and in combination with several pathogenic and food-spoilage bacteria such as Salmonella enterica, Bacillus cereus, Pseudomonas fluorescens, and Aeromonas hydrophila. Exposure to Lb. plantarum PA21 significantly reduced the number of P. fluorescens, A. hydrophila and B. cereus cells in the biofilm over 2-, 4- and 6-day time periods. However, despite the reduction in S. enterica cells, this pathogen showed greater resistance in the presence of PA21 developed biofilm, either in the planktonic or biofilm phase. Lb. plantarum PA21 was also found to be able to constitutively express GFP when transformed with the expression vector pMG36e which harbors the gfp gene as a reporter demonstrating that the newly isolated strain can be used as host for genetic engineering. CONCLUSION: In this study, we evaluate the ability of a new Lactobacillus isolate to form strong biofilm, which would provide the inhibitory effect against several spoilage and pathogenic bacteria. This new isolate has the potential to serve as a safe and effective cell factory for recombinant proteins.


Assuntos
Bacillus cereus/fisiologia , Biofilmes , Lactobacillus/fisiologia , Filogenia
9.
Int J Mol Sci ; 15(8): 14728-42, 2014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-25153628

RESUMO

In this work, biodegradable composites from poly(lactic acid) (PLA) and oil palm empty fruit bunch (OPEFB) fiber were prepared by melt blending method. Prior to mixing, the fiber was modified through bleaching treatment using hydrogen peroxide. Bleached fiber composite showed an improvement in mechanical properties as compared to untreated fiber composite due to the enhanced fiber/matrix interfacial adhesion. Interestingly, fiber bleaching treatment also improved the physical appearance of the composite. The study was extended by blending the composites with commercially available masterbatch colorant.


Assuntos
Peróxido de Hidrogênio/química , Ácido Láctico/química , Óleos de Plantas/química , Polímeros/química , Materiais Biocompatíveis/química , Microscopia Eletrônica de Varredura , Óleo de Palmeira , Poliésteres , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios X
10.
Molecules ; 19(3): 2957-68, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24609017

RESUMO

Bleaching treatment of kenaf fiber was performed in alkaline medium containing hydrogen peroxide solution maintained at pH 11 and 80 °C for 60 min. The bleached kenaf fiber was analyzed using Fourier Transform Infrared (FTIR) and X-ray Diffraction (XRD) analysis. The bleached kenaf fiber was then compounded with poly-(lactic acid) (PLA) via a melt blending method. The mechanical (tensile, flexural and impact) performance of the product was tested. The fiber treatment improved the mechanical properties of PLA/bleached kenaf fiber composites. Scanning electron micrograph (SEM) morphological analysis showed improvement of the interfacial adhesion between the fiber surface and polymer matrix.


Assuntos
Materiais Biocompatíveis/química , Hibiscus/química , Peróxido de Hidrogênio/química , Ácido Láctico/química , Fenômenos Mecânicos , Polímeros/química , Poliésteres , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
11.
Int J Mol Sci ; 15(2): 2274-88, 2014 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-24504029

RESUMO

The presence of phorbol esters (PEs) with toxic properties limits the use of Jatropha curcas kernel in the animal feed industry. Therefore, suitable methods to detoxify PEs have to be developed to render the material safe as a feed ingredient. In the present study, the biological treatment of the extracted PEs-rich fraction with non-pathogenic fungi (Trichoderma harzianum JQ350879.1, T. harzianum JQ517493.1, Paecilomyces sinensis JQ350881.1, Cladosporium cladosporioides JQ517491.1, Fusarium chlamydosporum JQ350882.1, F. chlamydosporum JQ517492.1 and F. chlamydosporum JQ350880.1) was conducted by fermentation in broth cultures. The PEs were detected by liquid chromatography-diode array detector-electrospray ionization mass spectrometry (LC-DAD-ESIMS) and quantitatively monitored by HPLC using phorbol-12-myristate 13-acetate as the standard. At day 30 of incubation, two T. harzianum spp., P. sinensis and C. cladosporioides significantly (p < 0.05) removed PEs with percentage losses of 96.9%-99.7%, while F. chlamydosporum strains showed percentage losses of 88.9%-92.2%. All fungal strains could utilize the PEs-rich fraction for growth. In the cytotoxicity assay, cell viabilities of Chang liver and NIH 3T3 fibroblast cell lines were less than 1% with the untreated PEs-rich fraction, but 84.3%-96.5% with the fungal treated PEs-rich fraction. There was no inhibition on cell viability for normal fungal growth supernatants. To conclude, Trichoderma spp., Paecilomyces sp. and Cladosporium sp. are potential microbes for the detoxification of PEs.


Assuntos
Biotransformação , Endófitos/metabolismo , Jatropha/química , Ésteres de Forbol/química , Trichoderma/metabolismo , Ração Animal , Animais , Carbono/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico , Meios de Cultura , Fermentação , Humanos , Ésteres de Forbol/toxicidade
12.
J Microbiol ; 51(5): 700-3, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24173648

RESUMO

The effect of Leucaena leucocephala hybrid-Bahru (LLB), which contains a high concentration of condensed tannins, on cellulolytic rumen fungal population in goats was investigated using real-time PCR. The fungal population in goats fed LLB was inhibited during the first 10 days of feeding, but after 15 days of feeding, there was a tremendous increase of fungal population (157.0 µg/ml), which was about fourfold more than that in control goats (39.7 µg/ml). However, after this period, the fungal population decreased continuously, and at 30 days of feeding, the fungal population (50.6 µg/ml) was not significantly different from that in control goats (55.4 µg/ml).


Assuntos
Biota , Fungos/classificação , Fungos/metabolismo , Rúmen/microbiologia , Anaerobiose , Animais , Celulose/metabolismo , Dieta/métodos , Fabaceae/metabolismo , Fungos/genética , Cabras , Hidrólise , Reação em Cadeia da Polimerase em Tempo Real
13.
Int J Mol Sci ; 12(9): 5955-70, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22016638

RESUMO

Defatted Jatropha curcas L. (J. curcas) seed kernels contained a high percentage of crude protein (61.8%) and relatively little acid detergent fiber (4.8%) and neutral detergent fiber (9.7%). Spectrophotometric analysis of the methanolic extract showed the presence of phenolics, flavonoids and saponins with values of 3.9, 0.4 and 19.0 mg/g DM, respectively. High performance liquid chromatography (HPLC) analyses showed the presence of gallic acid and pyrogallol (phenolics), rutin and myricetin (flavonoids) and daidzein (isoflavonoid). The amount of phorbol esters in the methanolic extract estimated by HPLC was 3.0 ± 0.1 mg/g DM. Other metabolites detected by GC-MS include: 2-(hydroxymethyl)-2 nitro-1,3-propanediol, ß-sitosterol, 2-furancarboxaldehyde, 5-(hydroxymethy) and acetic acid in the methanolic extract; 2-furancarboxaldehyde, 5-(hydroxymethy), acetic acid and furfural (2-furancarboxaldehyde) in the hot water extract. Methanolic and hot water extracts of kernel meal showed antimicrobial activity against both Gram positive and Gram negative pathogenic bacteria (inhibition range: 0-1.63 cm) at the concentrations of 1 and 1.5 mg/disc. Methanolic extract exhibited antioxidant activities that are higher than hot water extract and comparable to ß-carotene. The extracts tended to scavenge the free radicals in the reduction of ferric ion (Fe(3+)) to ferrous ion (Fe(2+)). Cytotoxicity assay results indicated the potential of methanolic extract as a source of anticancer therapeutic agents toward breast cancer cells.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Antioxidantes/química , Jatropha/química , Extratos Vegetais/química , Sementes/química , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Compostos de Bifenilo/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Células HeLa , Humanos , Células MCF-7 , Metanol/química , Testes de Sensibilidade Microbiana , Fenóis/análise , Ésteres de Forbol/análise , Picratos/antagonistas & inibidores , Picratos/química , Picratos/metabolismo , Extratos Vegetais/farmacologia , Saponinas/análise , Água/química
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