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1.
Environ Sci Pollut Res Int ; 30(12): 34481-34502, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36515877

RESUMO

Biodiesel is a biological renewable source produced from the conversion of triglycerides to alkyl esters. Palm oil is one of the most used lipid feedstocks for biodiesel production. It becomes necessary to optimize the transesterification reaction parameters to reduce the cost and enhance the quality of biodiesel. This study focuses on the use of homogenous sulfuric acid as a catalyst for the transesterification of palm fatty acids to methyl esters in a batch-scale reactor. A novel examination of transesterification reaction input parameters using the technique for order performance by similarity to ideal solution optimization technique and the effect of these parameters on yield, viscosity, and density of palm biodiesel using 3D surface graphs is investigated in this research. The present optimization approach is implemented to find out the optimum ranking of biodiesel production. From the experimental and numerical simulation, optimum results were observed at the catalyst concentration of 6% (w/w), reaction temperature of 70 °C, the reaction time of 120 min, and alcohol to oil molar ratio of 30:1 at which yield of 95.35%, viscosity of 5.0 cSt, and density of 880 kg/m3 of palm biodiesel were obtained. The different physicochemical properties of produced palm methyl esters are obtained within standards set by international authorities. Selected optimized process parameters can be used for commercial-scale biodiesel production.


Assuntos
Biocombustíveis , Óleos de Plantas , Óleo de Palmeira , Óleos de Plantas/química , Esterificação , Ésteres/química , Ácidos , Catálise , Etanol
2.
Sci Rep ; 11(1): 10187, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33986353

RESUMO

The severe outbreak of respiratory coronavirus disease 2019 has increased the significant demand of respiratory mask and its use become ubiquitous worldwide to control this unprecedented respiratory pandemic. The performance of a respiratory mask depends on the efficiency of the filter layer which is mostly made of polypropylene melt blown non-woven (PP-MB-NW). So far, very limited characterization data are available for the PPE-MB-NW in terms to achieve desired particulate filtration efficiency (PFE) against 0.3 µm size, which are imperative in order to facilitate the right selection of PP-MB-NW fabric for the development of mask. In present study, eight different kinds of PP-MB-NW fabrics (Sample A-H) of varied structural morphology are chosen. The different PP-MB-NW were characterized for its pore size and distribution by mercury porosimeter and BET surface area analyzer was explored first time to understand the importance of blind pore in PFE. The PP-MB-NW samples were characterized using scanning electron microscopy so as to know the surface morphology. The filtration efficiency, pressure drop and breathing resistance of various PP-MB-NW fabric samples are investigated in single and double layers combination against the particle size of 0.3, 0.5 and 1 µm. The samples which are having low pore dia, high solid fraction volume, and low air permeability has high filtration efficiency (> 90%) against 0.3 µm particle with high pressure drop (16.3-21.3 mm WC) and breathing resistance (1.42-1.92 mbar) when compared to rest of the samples. This study will pave the way for the judicial selection of right kind of filter layer i.e., PP-MB-NW fabric for the development of mask and it will be greatly helpful in manufacturing of mask in this present pandemic with desired PFE indicating considerable promise for defense against respiratory pandemic.


Assuntos
Filtros de Ar , COVID-19/prevenção & controle , Máscaras , Aerossóis/isolamento & purificação , Filtros de Ar/virologia , Desenho de Equipamento , Humanos , Máscaras/virologia , Tamanho da Partícula , Polipropilenos/química , SARS-CoV-2/isolamento & purificação , Têxteis/virologia
3.
Bioinformation ; 11(5): 236-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26124567

RESUMO

The cancer profile in the Indian state of Uttarakhand reveals that the breast cancer is the most prevalent type of cancers in females followed by cervical and ovarian type. Literature survey shows that the E6 protein of Human Papilloma Virus-16 (HPV-16) is responsible for causing several forms of cancer in human. Therefore, it is of interest to screen HPV-16 E6 target protein with known natural compounds using computer aided molecular modeling and docking tools. The complete structure of E6 is unknown. Hence, the E6 structure model was constructed using different online servers followed by molecular docking of Colchine, Curcumin, Daphnoretin, Ellipticine and Epigallocatechin-3-gallate; five known natural compounds with best E6 protein model predicted by Phyre2 server. The screening exercise shows that Daphnoretin (with binding free energy of -8.3 kcal/mol), a natural compound derived from Wikstroemia indica has the top binding properties. Thus, it is of interest to consider the compound for further validation.

4.
J Ethnopharmacol ; 136(1): 267-70, 2011 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-21550392

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Areca catechu nut extract is a popular folk remedy for the treatment of migraine in Kerala and Tamil Nadu states of India. AIM OF THE STUDY: In order to prove the claimed utilization of plant, the effect of hydroalcoholic extract of Areca catechu nut (ANE) was investigated in nitroglycerine induced inflammation in rat meninges. In these models infusion of nitric oxide donor glyceryl trinitrate (GTN) produces augmented plasma protein extravasation (PPE) in dura mater, provides an important substrate for the development of migraine in rats. MATERIALS AND METHODS: The effect on plasma protein extravasation was assessed in both the models of intravenous and topical GTN application following oral administration of ANE (250 mg/kg and 500 mg/kg) in both curative and preventive treatment and compared with that of control positive. The l-NAME (15 mg/kg, i.v.) was used as reference standard. Plasma protein extravasation was measured using fluorescein as marker and was measured using a Perkin-Elmer LS-30 luminescence spectrometer. RESULTS: Expression of iNOS in the spleen after intravenous injection produced PPE into the dura mater in control positive group was significantly (P<0.01) reduced to 1.553±0.02499 and 1.398±0.01887 by preventive treatment with ANE at the dose of 250 and 500 mg/kg, orally, respectively. The extravasation produced by topical GTN due to expression of iNOS in dural macrophages was also reduced to 1.555±0.03384 and 1.425±0.01204 by preventive treatment with ANE at the dose of 250 and 500 mg/kg, orally, respectively. While ANE do not showed any significant results in curative treatment in both the models of i.v. and topical GTN application. CONCLUSION: These findings collectively indicate that the extract exhibited significant inhibition of iNOS, which may be the probable mechanism for its anti-migraine activity, providing evidence, at least in part, for its folkloric use.


Assuntos
Anti-Inflamatórios/uso terapêutico , Areca , Proteínas Sanguíneas/metabolismo , Meningite/tratamento farmacológico , Transtornos de Enxaqueca/tratamento farmacológico , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Fitoterapia , Animais , Anti-Inflamatórios/farmacologia , Modelos Animais de Doenças , Dura-Máter/efeitos dos fármacos , Dura-Máter/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Macrófagos/efeitos dos fármacos , Masculino , Meningite/induzido quimicamente , Meningite/metabolismo , Camundongos , Camundongos Endogâmicos , Transtornos de Enxaqueca/induzido quimicamente , Transtornos de Enxaqueca/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Nitroglicerina/metabolismo , Nozes , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Baço/metabolismo
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