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1.
Sci Rep ; 14(1): 13228, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853164

RESUMO

Petroleum fuels are commonly used for automobiles. However, the continuous depletion and exhaust gas emission causes serious problems. So, there is a need for an alternative eco-friendly fuel. Biodiesel is a type of fuel manufactured through a process called transesterification, which involves converting vegetable oils into a usable form. The process parameters of the transesterification process were optimized using the Taguchi method to achieve maximum biodiesel yield. However, the main problem of biodiesel is its high cost which could be reduced by using low-cost feedstock. To address this challenge, biodiesel (BCFAD) is derived from coconut fatty acid distillate (CFAD), a by-product obtained from refining coconut oil. This work uses BCFAD and BCFAD with Alumina nanoparticles as fuels. Alumina nanoparticles in the mass fraction of 25 ppm, 50 ppm, and 100 ppm are dispersed in BCFAD. The investigation results reveal an increase of 6.5% in brake thermal efficiency for BCFAD with 100 ppm nanoparticles when compared to BCFAD. There is a reduction of 29.29% of hydrocarbon and 34% of Carbon monoxide emissions with BCFAD100 in comparison with diesel. However, there is a marginal increase in NOx emission with the increase in nanoparticles. The heat release rate and cylinder pressure of BCFAD100 are comparable to diesel fuel. It was concluded that the utilization of BCFAD with a nanoparticle dispersion of 100 ppm is suitable for direct use as fuel in diesel engines.

2.
Asian Pac J Cancer Prev ; 13(6): 2729-34, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22938449

RESUMO

Despite clinical advances in anticancer therapy, there is still a need for novel anticancer metabolites, with higher efficacy and lesser side effects. Oroxylum indicum (L.) Vent. is a small tree of the Bignoniaceae family which is well known for its food and medicinal properties. In present study, the chemopreventive properties of O. indicum hot and cold non-polar extracts (petroleum ether and chloroform) were investigated with MDA- MB-231 (cancer cells) and WRL-68 (non-tumor cells) by XTT assay. All the extracts, and particularly the petroleum ether hot extract (PHO), exhibited significantly (P<0.05) higher cytotoxicity in MDA-MB-231 when compared to WRL-68 cells. PHO was then tested for apoptosis induction in estrogen receptor (ER)-negative (MDA-MB-231) and ER-positive (MCF-7) breast cancer cells by cellular DNA fragmentation ELISA, where it proved more efficient in the MDA-MB-231 cells. Further, when PHO was tested for anti-metastatic potential in a cell migration inhibition assay, it exhibited beneficial effects. Thus non-polar extracts of O. indicum (especially PHO) can effectively target ER-negative breast cancer cells to induce apoptosis, without harming normal cells by cancer-specific cytotoxicity. Hence, it could be considered as an extract with candidate precursors to possibly harness or alleviate ER-negative breast cancer progression even in advanced stages of malignancy.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Bignoniaceae , Neoplasias da Mama/tratamento farmacológico , Fitoterapia , Extratos Vegetais/farmacologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Quimioprevenção , Feminino , Humanos , Receptores de Estrogênio/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-19875433

RESUMO

Cyanthillium cinereum (Less.) H. Rob. (Asteraceae) has been traditionally known for its medicinal properties, all aspects of which are yet to be exploited. This study was aimed at investigating the therapeutic potential of polar (methanolic and aqueous) and nonpolar (hexane and chloroform) crude extracts of the whole plant. Several parameters including free-radical (DPPH(•), ABTS(•+), H(2)O(2) and (•)OH) scavenging, reducing power, protection of DNA against oxidative damage, cytotoxicity, inhibition of oxidative hemolysis in erythrocytes, total phenolic content and inhibition of lipid peroxidation were examined. All the free-radical generating assay models demonstrated positive scavenging efficiency with differential but considerable magnitudes for the four extracts. However, only the hexane extract showed significant H(2)O(2) scavenging effect. Lipid peroxidation was estimated by thiobarbituric acid-malondialdehyde (MDA) reaction, and a high degree of inhibition was shown by all the extracts. Reducing power of the polar extracts was higher than the non-polar ones. All extracts showed a concentration-dependent increase in phenolic contents. Oxidative damage to erythrocytes was hindered by all extracts in diverse degrees. XTT assay showed that all extracts have mild cytotoxic property. The aqueous extract evidently demonstrated protective effect on pBR322 plasmid DNA against oxidative breakdown. These results suggested the potential of C. cinereum as medicine against free-radical-associated oxidative damage and related degenerative diseases involving metabolic stress, genotoxicity and cytotoxicity.

4.
Food Chem Toxicol ; 48(12): 3449-57, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20854871

RESUMO

Antimycin A (AMA) treatment of cells blocks mitochondrial electron transport chain, and leads to elevated ROS generation, thereby causing damage to mtDNA, proteins and lipids, along with mitochondrial membrane depolarization, release of pro-apoptotic proteins into the cytoplasm, and induction of apoptosis. Prevention of such oxidative cellular damage by the aqueous extract of Phyllanthus amarus has been investigated in this study. The extract demonstrated significant potential in mitigating H(2)O(2)-induced membrane damage along with considerable recession in AMA-governed mitochondrial protein and lipid degradation in Hep3B cells. 8-OHdG analysis of mtDNA damage revealed substantial protective potential of the extract against mtDNA damage. SQ-PCR of selected mtDNA sequences confirmed the potential of the extract to alleviate levels of mtDNA damage. FACS analysis with JC-1 fluorescent dye established significant escalation of mitochondrial membrane potential by the extract in AMA-treated cells. Extract treatment resulted in a distinct decline in the degrees of AMA-induced release of cytochrome c and AIF into the cytoplasm along with consequent pacification of apoptosis. All protective efficiencies of the extract reported in this study were found to hold strong and significant (P<0.05) positive correlation to its total phenolic contents, thereby proving that polyphenolic constituents of P. amarus aqueous extract mitigate oxidative stress-induced cellular degeneration and aging.


Assuntos
Antibacterianos/antagonistas & inibidores , Antibacterianos/farmacologia , Antimicina A/antagonistas & inibidores , Antimicina A/farmacologia , Apoptose/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Phyllanthus/química , 8-Hidroxi-2'-Desoxiguanosina , Fator de Indução de Apoptose/farmacologia , Bromodesoxiuridina , Linhagem Celular , Corantes , Citocromos c/metabolismo , DNA Mitocondrial/antagonistas & inibidores , DNA Mitocondrial/isolamento & purificação , Desoxiguanosina/análogos & derivados , Citometria de Fluxo , Humanos , Técnicas In Vitro , Indicadores e Reagentes , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/ultraestrutura , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/metabolismo , Fenóis/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sais de Tetrazólio , Tiazóis
5.
Food Chem Toxicol ; 48(8-9): 2133-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20472016

RESUMO

This study was aimed at investigating the phenolic constituents of methanolic and aqueous extracts of Vitex negundo in context of antioxidant potential and inhibition of oxidative stress-induced cytotoxicity. Antioxidant efficacies of both extracts were estimated by their abilities to scavenge DPPH(*) and to reduce Fe(+3) to Fe(+2). Their protective potential against H(2)O(2)-driven oxidative damage to cells were evaluated by XTT assay in Hep3B (human hepatoma) cells. Total phenolic content of both extracts were estimated, and were tested for correlation with antioxidant potential and protection against oxidative cytotoxicity. Polyphenolic levels in both extracts showed significant (P<0.05) positive correlations with DPPH(*) scavenging, Fe(+3)-Fe(+2) reduction and percentage decrease in H(2)O(2)-induced cytotoxicity. Major phenolic compounds in the extracts were identified by HPLC. It was concluded that both V. negundo extracts hold considerable potential as antitheses of free radical toxicity by virtue of their polyphenolic constituents, and might have significant clinical roles in prospect.


Assuntos
Flavonoides/análise , Flavonoides/farmacologia , Fenóis/análise , Fenóis/farmacologia , Substâncias Protetoras/análise , Substâncias Protetoras/farmacologia , Vitex/química , Benzotiazóis/química , Compostos de Bifenilo/química , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Compostos Férricos/química , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Humanos , Peróxido de Hidrogênio/toxicidade , Indicadores e Reagentes , Peroxidação de Lipídeos/efeitos dos fármacos , Metanol , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Picratos/química , Extratos Vegetais/química , Polifenóis , Solventes , Ácidos Sulfônicos/química , Água
6.
Food Chem Toxicol ; 48(1): 396-401, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19874864

RESUMO

Cr(VI) (hexavalent) is a very strong oxidant which causes high cytotoxicity through oxidative stress in tissue systems. Its abundance in groundwater and drinking water in several parts of the world has been noted to cause severe toxicity to both flora and fauna. This study evaluated the effects of aqueous extract of Phyllanthus amarus Schum. & Thon. against Cr(VI)-induced oxidative toxicity in vitro in MDA-MB-435S human breast carcinoma cells, along with an estimation of its antioxidant potential, inhibition of lipid peroxidation and determination of its polyphenolic composition. The extract showed significant (P<0.05) potential in scavenging free radicals (DPPH() and ABTS()(+)) and Fe(+3), and in inhibiting lipid peroxidation. A distinct decline in Cr(VI)-induced cytotoxicity was noticed in MDA-MB-435S cells with an increase in extract dosage. Furthermore, the extract proved to contain a high content of phenolic compounds which were found to have strong and significant (P<0.05) positive correlations to free-radical scavenging potential, lipid peroxidation inhibition capacity and cyto-protective efficiency against Cr(VI)-induced oxidative cellular damage. HPLC analysis identified some of the major phenolic compounds in it. It was concluded that P. amarus aqueous extract has high antioxidant potential (by virtue of its phenolic constituents) which simultaneously inhibits Cr(VI)-induced oxidative toxicity to MDA-MB-435S cells.


Assuntos
Cromo/antagonistas & inibidores , Cromo/toxicidade , Phyllanthus/química , Antioxidantes/farmacologia , Benzotiazóis , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Compostos de Cromo/antagonistas & inibidores , Compostos de Cromo/toxicidade , Corantes , Relação Dose-Resposta a Droga , Feminino , Compostos Férricos/química , Flavonoides/química , Flavonoides/farmacologia , Sequestradores de Radicais Livres/farmacologia , Humanos , Indicadores e Reagentes , Peroxidação de Lipídeos/efeitos dos fármacos , Oxidantes/química , Estresse Oxidativo , Fenóis/química , Fenóis/farmacologia , Picratos/antagonistas & inibidores , Picratos/química , Extratos Vegetais/farmacologia , Ácidos Sulfônicos , Sais de Tetrazólio
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