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1.
Food Chem ; 337: 127771, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32777564

RESUMO

Faveleira (Cnidoscolus quercifolius) is an emerging Brazilian plant, with seeds rich in edible oil. This study investigates physicochemical properties, chemical composition, thermal and oxidative stability, in vitro and in vivo toxicity, antioxidant, antinociceptive and anti-inflammatory activities of faveleira seed oil. It was observed that the oil has low acidity, value of peroxide, chlorophyll, carotenoids, ß-carotene and high concentrations of unsaturated fatty acids. In addition to presenting thermal and oxidative stability and high total phenolic content, with vanillin, eugenol and quercetin were predominating. The oil showed no toxicity in vitro and in vivo, and presented antioxidant, anti-inflammatory and antinociceptive activities. These findings provide relevant and appropriate conditions for processing of faveleira seed oil as functional food.

2.
BMC Biotechnol ; 20(1): 55, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33066751

RESUMO

BACKGROUND: Buriti oil presents numerous health benefits, but due to its lipophilic nature and high oxidation, it is impossible to incorporate it into aqueous food matrices. Thus, the present study evaluated whether powder nanoparticles based on porcine gelatin (OPG) and in combination with sodium alginate (OAG) containing buriti oil obtained by O/W emulsification followed by freeze-drying enabled water dispersibility and preserved or increased the antimicrobial activity of the oil. RESULTS: OPG presented spherical shape, smooth surface, smaller particle size and polydispersity index [51.0 (6.07) nm and 0.40 (0.05)], and better chemical interaction between the nonpolar amino acids and the hydrophobic oil chain. OPG also presented a higher dispersibility percentage [85.62% (7.82)] than OAG [50.19% (7.24)] (p < 0.05), and significantly increased the antimicrobial activity of the oil by 59, 62, and 43% for Pseudomonas aeruginosa, Klebsiella pneumonia, and Staphylococcus aureus, respectively. CONCLUSIONS: Thus, nanoencapsulation in gelatin is a promising strategy to increase the potential to use buriti oil in foods.

3.
Appl Biochem Biotechnol ; 170(2): 292-300, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23504592

RESUMO

Obtaining oligosaccharides from chitosan has been the focus of several studies in the pharmaceutical, chemical, food, and medical areas, due to their functional properties. Here, we evaluated the production potential of biologically functional chitooligosaccharides using enzymes extracts produced by Paenibacillus chitinolyticus and Paenibacillus ehimensis. After 48 h of fermentation, these microorganisms were able to produce chitosanases, which generated oligomers with a degree of polymerization between dimers and hexamers. The maximum conversion of chitosan to oligomers was 99.2 %, achieved after 12 h incubation of chitosan with enzymes produced by P. ehimensis. The chitooligosaccharides generated were capable of scavenging the 2,2-diphenyl-1-picrylhydrazyl radical, reaching a maximum scavenging rate of 61 and 39 % when produced with P. ehimensis and P. chitinolyticus enzymes, respectively. The use of these enzymes in the crude form could facilitate their use in industrial applications.


Assuntos
Proteínas de Bactérias/metabolismo , Quitosana/metabolismo , Glicosídeo Hidrolases/metabolismo , Oligossacarídeos/metabolismo , Paenibacillus/enzimologia , Compostos de Bifenilo/metabolismo , Ativação Enzimática , Fermentação , Depuradores de Radicais Livres/metabolismo , Hidrólise , Picratos/metabolismo , Polimerização
4.
World J Microbiol Biotechnol ; 28(3): 1097-105, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22805831

RESUMO

Chitooligosaccharides (COS) are partially hydrolyzed compounds derived from chitosan that exhibit a number of biological activities, including antitumor, antibacterial and antifungal properties. In this work, we examined the cytotoxicity of pure COS and oligomers A, B and C (solutions composed of different amounts of COS) produced by enzymatic hydrolysis using a crude enzyme extract produced by the fungus Metarhrizium anisopliae. The antiproliferative effect of these molecules was analyzed using tumor cell lines (HepG2 and HeLa cells) and in a normal cell line (3T3). The antioxidant activity was analyzed in several in vitro experiments. Glucosamine showed higher toxicity (approximately 92%) to all cell lines studied. However, the oligomers obtained after hydrolysis demonstrated no toxic effects on the normal cells (3T3). Furthermore, we showed that a small amount of other COS can decrease the cytotoxic effect of glucosamine against 3T3 cells, indicating that glucosamine could be used as an antitumor drug in the presence of other COS. In addition, different effects were found in antiproliferative assays, which depended on the COS composition in the oligomers (A, B and C), showing that a combination of them may be essential for developing antineoplastic drugs. Superoxide anion scavenging was the main antioxidant activity demonstrated by the COS and oligomers. This activity was also dependent on the oligomer composition of the chitosan hydrolysates. Further work will identify the ideal proportions of COS and glucosamine for maximizing the effects of these biological activities.


Assuntos
Quitosana/metabolismo , Glucosamina/antagonistas & inibidores , Glucosamina/toxicidade , Oligossacarídeos/metabolismo , Animais , Antioxidantes/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Humanos , Metarhizium/enzimologia , Camundongos
5.
Bioprocess Biosyst Eng ; 33(7): 893-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20165886

RESUMO

The products of chitosan hydrolysis are chitooligosaccharides and are used mainly for medical applications due to their specific biological activities. The objective of this study was to detect and identify the products of enzymatic hydrolysis of chitosan (dimers to hexamers) using a crude extract of chitosanolytic enzymes produced by the fungus Metarhizium anisopliae. These fungus was able to produce, during 48 h cultivation in a medium containing chitosan, chitooligosaccharides ranging from dimers, trimers, tetramers and pentamers at concentrations 0.2, 0.19, 0.06, 0.04 mg/mL, respectively, and the enzymatic activity was 2.5 U/L. Using the crude enzyme extract for chitosan hydrolysis, we detected the presence of dimers to hexamers at hydrolysis times of 10, 20, 30, 40, 50 and 60 min of enzymatic reaction, but the yields were higher at 10 min (54%). The hexamers was obtained only with 30 min of reaction with concentration of 0.004 mg/mL.


Assuntos
Quitosana/química , Quitosana/metabolismo , Metarhizium/enzimologia , Oligossacarídeos/química , Oligossacarídeos/metabolismo , Hidrólise
6.
Leuk Res ; 27(9): 823-9, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12804641

RESUMO

Oxidative stress can be involved in several cellular responses, such as differentiation, apoptosis and necrosis. Dehydrocrotonin (DCTN, diterpene lactone) from Croton cajucara, Brazilian medicinal plant, slightly induced NBT-reducing activity. In presence of protein phosphatase inhibitors significant differentiation of HL60 cells was observed. Flow cytometry analysis demonstrated that apoptosis was induced when the cells were treated with okadaic acid (OKA) and plus trans-dehydrocrotonin (t-DCTN) this effect was two-fold increased. Unlike, when the cells were treated only with t-DCTN, necrosis was observed. On the other hand, the necrosis induced by t-DCTN could be due to oxidative stress, revealed by increase of GSH content. Therefore, this differentiation pathway involves the modulation of protein phosphatases and this inhibition promotes the t-DCTN action on apoptosis induction.


Assuntos
Apoptose/efeitos dos fármacos , Diterpenos Clerodânicos , Diterpenos/farmacologia , Inibidores Enzimáticos/farmacologia , Leucemia Promielocítica Aguda/metabolismo , Ácido Okadáico/farmacologia , Fosfoproteínas Fosfatases/antagonistas & inibidores , Anexina A5/metabolismo , Brasil , Diferenciação Celular/efeitos dos fármacos , Croton , Ensaios de Seleção de Medicamentos Antitumorais , Citometria de Fluxo , Glutationa/metabolismo , Células HL-60/patologia , Humanos , Leucemia Promielocítica Aguda/patologia , Necrose , Estresse Oxidativo/efeitos dos fármacos , Fosfoproteínas Fosfatases/metabolismo , Plantas Medicinais , Vanadatos/farmacologia
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