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1.
Foods ; 11(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36553704

RESUMO

The purpose of this research was to assess and utilize the bioactive compounds of garlic nanoparticles (Ga-NPs) as a natural antioxidant in sunflower oil (SFO) stored at 65 ± 1 °C for 24 days. The garlic nanoparticles (Ga-NPs) from the Balady cultivar were prepared, characterized, and added to SFO at three concentrations: 200, 600, and 1000 ppm (w/v), and they were compared with 600 ppm garlic lyophilized powder extract (Ga-LPE), 200 ppm BHT, 200 ppm α-tocopherol, and SFO without Ga-NPs (control). The QTRAP LC/MS/MS profile of Ga-NPs revealed the presence of four organosulfur compounds. Ga-NPs exhibited the highest capacity for phenolic, flavonoid, and antioxidant compounds. In Ga-NP SFO samples, the values of peroxide, p-anisidine, totox, conjugated dienes, and conjugated trienes were significantly lower than the control. The antioxidant indices of SFO samples containing Ga-NPs were higher than the control. The Ga-NPs enhanced the sensory acceptability of SFO treatments up to day 24 of storage. The shelf life of SFO treated with Ga-NPs was substantially increased (presuming a Q10 amount). The results show that Ga-NPs are a powerful antioxidant that improves SFO stability and extends the shelf life (~384 days at 25 °C).

2.
Biomed Pharmacother ; 143: 112148, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34560553

RESUMO

Ulcerative colitis (UC) is a gastrointestinal inflammatory disease with a multifactorial pathophysiology. This study aims to investigate the immunomodulatory effect of Portulaca oleracea leaf ethanolic extract (POE) on acetic acid (AA)-induced UC in mice. Experimental animals received oral doses of POE (200 mg/kg for 7 days) after an induction of colitis by intrarectal AA administration. In mice with AA-induced UC treated with POE, the results revealed a significant modulation in body weight and colon length. Moreover, treatment with POE downregulated the interleukin 1, 6, and 17, tumor necrosis factor-alpha, gamma interferon, and nuclear factor-kappa B levels compared with the colitis group. Furthermore, POE markedly inhibited histological damage, decreased myeloperoxidase activity and reduced fecal calprotectin level compared with the colitis group. These data are consistent with the reduction in total bacterial content in the colon. Taken together, treatment with POE may reduce colonic inflammation by alleviating the immune response and inhibiting the severity of colitis. The HPLC analysis of POE resulted in the identification of seven medicinal compounds comprising two phenolic acids (ferulic and caffeic acids) and five flavonoids (kaempferol, quercetin, rutin, narenginin and hesperidin). Subsequent analysis of POE by GC-MS revealed ten phytocomponents; the major percentages were hexadecenoic acid, methyl ester (29.8119%), α-linolenic acid (25.8431%), 16-octadecenoic acid, methyl ester (15.1578%) and α-tocopherol (10.7848%). Delta-lactams and alkanes were the minor components. Such natural plant-derived substances and their probable synergistic action appear to contribute to a promising therapeutic protocol for colitis.


Assuntos
Colite/tratamento farmacológico , Agentes de Imunomodulação/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Portulaca , Animais , Colite/imunologia , Colite/metabolismo , Colite/microbiologia , Citocinas/metabolismo , Modelos Animais de Doenças , Microbioma Gastrointestinal , Agentes de Imunomodulação/isolamento & purificação , Mediadores da Inflamação/metabolismo , Complexo Antígeno L1 Leucocitário/metabolismo , Masculino , Camundongos , NF-kappa B/metabolismo , Peroxidase/metabolismo , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Portulaca/química
3.
BMC Microbiol ; 5: 41, 2005 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-16000176

RESUMO

BACKGROUND: Metal reduction is thought to take place at or near the bacterial outer membrane and, thus, outer membrane proteins in the model dissimilatory metal-reducing organism Geobacter sulfurreducens are of interest to understand the mechanisms of Fe(III) reduction in the Geobacter species that are the predominant Fe(III) reducers in many environments. Previous studies have implicated periplasmic and outer membrane cytochromes in electron transfer to metals. Here we show that the most abundant outer membrane protein of G. sulfurreducens, OmpJ, is not a cytochrome yet it is required for metal respiration. RESULTS: When outer membrane proteins of G. sulfurreducens were separated via SDS-PAGE, one protein, designated OmpJ (outer membrane protein J), was particularly abundant. The encoding gene, which was identified from mass spectrometry analysis of peptide fragments, is present in other Geobacteraceae, but not in organisms outside this family. The predicted localization and structure of the OmpJ protein suggested that it was a porin. Deletion of the ompJ gene in G. sulfurreducens produced a strain that grew as well as the wild-type strain with fumarate as the electron acceptor but could not grow with metals, such as soluble or insoluble Fe(III) and insoluble Mn(IV) oxide, as the electron acceptor. The heme c content in the mutant strain was ca. 50% of the wild-type and there was a widespread loss of multiple cytochromes from soluble and membrane fractions. Transmission electron microscopy analyses of mutant cells revealed an unusually enlarged periplasm, which is likely to trigger extracytoplasmic stress response mechanisms leading to the degradation of periplasmic and/or outer membrane proteins, such as cytochromes, required for metal reduction. Thus, the loss of the capacity for extracellular electron transport in the mutant could be due to the missing c-type cytochromes, or some more direct, but as yet unknown, role of OmpJ in metal reduction. CONCLUSION: OmpJ is a putative porin found in the outer membrane of the model metal reducer G. sulfurreducens that is required for respiration of extracellular electron acceptors such as soluble and insoluble metals. The effect of OmpJ in extracellular electron transfer is indirect, as OmpJ is required to keep the integrity of the periplasmic space necessary for proper folding and functioning of periplasmic and outer membrane electron transport components. The exclusive presence of ompJ in members of the Geobacteraceae family as well as its role in metal reduction suggest that the ompJ sequence may be useful in tracking the growth or activity of Geobacteraceae in sedimentary environments.


Assuntos
Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Compostos Férricos/metabolismo , Geobacter/imunologia , Compostos de Manganês/metabolismo , Óxidos/metabolismo , Sequência de Aminoácidos , Proteínas da Membrana Bacteriana Externa/química , Sequência de Bases , Transporte Biológico , Primers do DNA , Deltaproteobacteria/genética , Deltaproteobacteria/metabolismo , Deleção de Genes , Genoma Bacteriano , Geobacter/classificação , Geobacter/genética , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Filogenia , Estrutura Secundária de Proteína , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
4.
FEMS Microbiol Lett ; 226(1): 107-12, 2003 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-13129615

RESUMO

The respiratory arsenate reductase from the Gram-positive, haloalkaliphile, Bacillus selenitireducens strain MLS10 was purified and characterized. It is a membrane bound heterodimer (150 kDa) composed of two subunits ArrA (110 kDa) and ArrB (34 kDa), with an apparent K(m) for arsenate of 34 microM and V(max) of 2.5 micromol min(-1) mg(-1). Optimal activity occurred at pH 9.5 and 150 g l(-1) of NaCl. Metal analysis (inductively coupled plasma mass spectrometry) of the holoenzyme and sequence analysis of the catalytic subunit (ArrA; the gene for which was cloned and sequenced) indicate it is a member of the DMSO reductase family of molybdoproteins.


Assuntos
Arseniatos/metabolismo , Bacillus/enzimologia , Bombas de Íon , Ácido Láctico/metabolismo , Complexos Multienzimáticos , ATPases Transportadoras de Arsenito , Bacillus/genética , Cromatografia em Gel , Cromatografia por Troca Iônica , Estabilidade Enzimática/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Bombas de Íon/química , Bombas de Íon/genética , Bombas de Íon/isolamento & purificação , Bombas de Íon/metabolismo , Dados de Sequência Molecular , Peso Molecular , Complexos Multienzimáticos/química , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/isolamento & purificação , Complexos Multienzimáticos/metabolismo , Subunidades Proteicas/genética , Subunidades Proteicas/isolamento & purificação , Análise de Sequência de DNA , Análise de Sequência de Proteína , Cloreto de Sódio/farmacologia , Ultracentrifugação
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