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1.
Metabolites ; 13(8)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37623866

RESUMO

The twigs of sea buckthorn, blackcurrant, gooseberries, quince, and grapes were evaluated as a promising source of biologically active compounds-proanthocyanidins (PACs). Sea buckthorn twigs had the highest content of PACs (9.2% on dry biomass). Preliminary pretreatment of biomass with freon R134a did not allow an increase in PACs content in the composition of hydrophilic extract but confirmed the value of freon extract as an antibacterial agent against P. aeruginosa and B. cereus. The content of PACs was used as an indicator for assessment of the influence of hydrophilic extracts on pancreatic lipase activity. Under normal physiological conditions, in the presence of bile, the extract, which contained 42.4% of PACs was more effective compared to the extract which contained 17.5% of PACs. At all concentrations (0.2-40 mg of sample/g of pancreatic lipase), it inhibited lipase activity by 33%. Purified PACs were the most effective in inhibiting lipase activity (by 36%). However, in pathological physiological conditions (without bile), the opposite effect on lipase activity was observed. Thus, PACs and extracts can be used as inhibitors of pancreatic lipase only under normal physiological conditions.

2.
Plants (Basel) ; 11(5)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35270111

RESUMO

For sustainable sea buckthorn (Hippophae rhamnoides) berry production, the task at hand is to find an application for the large amount of biomass waste arising at harvesting. Sea buckthorn (SBT) vegetation is currently poorly studied. The purpose of this research was to assess the composition and potential of SBT twigs as a source of valuable biologically active substances. Water and 50% EtOH extracts of twigs of three Latvian SBT cultivars with a high berry yield and quality, popular for cultivation in many countries (H. rhamnoides 'Maria Bruvele', 'Tatiana', 'Botanicheskaya Lubitelskaya'), were investigated for the first time. The phytochemical composition (UHPLC-ESI-MS/MS analysis) and biological activity of the obtained hydrophilic extracts were determined. The highest yield of polyphenolic compounds and serotonin was observed for 'Maria Bruvele'. Hydrophilic extracts were investigated for radical scavenging activity (DPPH˙ test), antibacterial/antifungal activity against five pathogenic bacteria/yeast, cytotoxicity, and the enzymatic activity of alpha-amylase (via in vitro testing), which is extremely important for the treatment of people with underweight, wasting, and malabsorption. The results showed a high potential of sea buckthorn biomass as a source of valuable biologically active compounds for the creation of preparations for the food industry, nutraceuticals, and cosmetics.

3.
Antioxidants (Basel) ; 9(8)2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32785182

RESUMO

Nowadays, approximately 1 billion kg/y of grape stalks, with a remarkable polyphenols content, are produced worldwide. In this paper, the extraction process intensification of polyphenols in water was achieved under ultrasound-assisted recovery, focusing on kinetics and scaling-up factors. Immersion and cup-horn systems were exploited as acoustic cavitation sources, and the total phenolic content (TPC) was chosen to assess the process efficiency. The kinetics were evaluated by Peleg's hyperbolic model, and the effect of both the initial feedstock granulometry and ultrasound size-reduction were determined. The results were compared with conventional extraction methods (data analysis by ANOVA). The best polyphenols yield was obtained after 45 min of sonication, giving between 29.71 and 31.89 mg/g (gallic acid equivalents over the dry matter). The extracts were characterized using HPLC-DAD, UPLC-ESI-MS/MS, DPPH• assay (2,2-diphenyl-1-picrylhydrazyl), TEAC assay (Trolox equivalent antioxidant capacity), and proanthocyanidin content determination. The flow-mode extraction procedure of grape stalks (2 kg) was carried out in a 15 L reactor. A semi-industrial decanter unit and a bag-filter were the keys units of the downstream operations. The resulting particle-free solution underwent nanofiltration on a membrane pilot skid, providing a final polyphenols-enriched stream concentrated up to 355.91%, as shown by the antioxidant activity and TPC.

4.
Molecules ; 24(9)2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31075868

RESUMO

The valorization of lignins as renewable aromatic feedstock is of utmost importance in terms of the use of sustainable resources. This study provides a deductive approach towards market-oriented lignin-derived antioxidants by ascertaining the direct effect of different structural features of lignin on the reactivity of its phenolic OH groups in the radical scavenging reactions. The antioxidant activity of a series of compounds, modeling lignin structural units, was experimentally characterized and rationalized, using thermodynamic descriptors. The calculated O-H bond dissociation enthalpies (BDE) of characteristic lignin subunits were used to predict the modification pathways of technical lignins. The last ones were isolated by soda delignification from different biomass sources and their oligomeric fractions were studied as a raw material for modification and production of optimized antioxidants. These were characterized in terms of chemical structure, molecular weight distribution, content of the functional groups, and the antioxidant activity. The developed approach for the targeted modification of lignins allowed the products competitive with two commercial synthetic phenolic antioxidants in both free radical scavenging and stabilization of thermooxidative destruction of polyurethane films.


Assuntos
Antioxidantes/síntese química , Teoria da Densidade Funcional , Lignina/química , Modelos Teóricos , Dimerização , Elétrons , Hidrogênio/química , Cinética , Polifenóis/química , Poliuretanos/química , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
5.
Food Res Int ; 115: 200-208, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599932

RESUMO

The use of zero-waste processes to integrate food-waste valorisation into the circular economy equation is currently one of the hottest topics in sustainability research. This goal is still far from being fully achieved despite the release of a number of patents and papers that deal with the topic. The present work aims to valorise cocoa shells, one of the main by-product of the roasting process, in order to enhance the effective extraction of high added value compounds by means of green protocols. The high potential added value of the residual waste has been demonstrated via a direct analytical comparison of extracts and bean composition. A range of raw matrix extraction procedures have been investigated in order to define the best solvent and technology; ultrasound (US) and hydrodynamic cavitation (HC) were compared with conventional methods. The high-energy microenvironments generated by cavitation substantially promote fast biomass deconstruction with low energy consumption. The optimized protocol couples a HC reactor with a ternary water/ethanol/hexane mixture, simultaneously providing a hydrophilic product, which is rich in methylxanthines and polyphenols, and a lipid layer. Sequential milling and sieving pretreatment provided an enriched shell fraction via the partial removal of husk fibres (54.45 vs. 81.36 w/w % total fibres). The disposal of the latter reduces mass balance, but is rerouted into animal feedstock components and crop mulching. The protocols herein reported produce valuable extracts, which are rich in antioxidant flavanols (catechins and epicatechins), theobromine (32.7 ±â€¯0.12 mg/g shells), caffeine (1.76 ±â€¯0.08 mg/g shells) and cocoa butter, in a simple and easy manner. This new valorisation process afforded 20.5 w/w % and 15.8 w/w % hydrophilic and lipophilic fractions, respectively, when scaled up to function in a pilot flow reactor. The fatty acids, obtained in remarkable yield (forming the 96.4 w/w % of the total light part) well match the commercial cocoa butter profile. The antioxidant extract shows an impressive total phenolic content of 197.4 mg/g extract (gallic acid eq.), with a radical scavenging activity of 62.0 ±â€¯3.1 µg/mL (expressed in DPPH EC50). This work should facilitate industrial design for the convenient recovery of cocoa by-products as part of a zero-waste strategy.


Assuntos
Cacau/química , Extratos Vegetais/química , Resíduos , Ração Animal , Antioxidantes/análise , Biomassa , Carboidratos/análise , Catequina/análise , Flavanonas/análise , Indústria Alimentícia , Fenóis/análise , Polifenóis/análise , Solventes , Teobromina/análise , Xantinas
6.
Data Brief ; 22: 56-64, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30581905

RESUMO

Full analytical data of Ecuadorian cocoa wastes (raw shells) and beans (as benchmark), are herein reported. A detailed characterization of production residues may pave the road to a zero-waste strategy for the cocoa industry. Multiple analytical techniques have been exploited to define the composition of the matrices, among them: elemental analyses, FTIR, Py-GC/MS/FID and UHPLC-ESI-MS/MS. Quali-quantitative data of carbohydrates, lipids, lignin, polyphenols, alkaloids and proteins have been obtained by Py-GC/MS/FID and UHPLC-ESI-MS/MS. Assignations are fully supported by literature references. The FAMEs composition of lipophilic UAE extract is also reported for sake of comparison with cocoa butter. This data collection completes a wider valorization work, "Cocoa bean shell waste valorisation; extraction from lab to pilot-scale cavitational reactors" (Grillo et al., 2018).

7.
Biochem Biophys Res Commun ; 458(3): 693-699, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25686497

RESUMO

Inflammation in the vascular wall is important for the development of atherosclerosis. We have previously shown that inflammatory macrophages are more abundant in human atherosclerotic lesions than in healthy arteries. Activated macrophages produce reactive oxygen species (ROS) that promote local inflammation in atherosclerotic lesions. Here, we investigated the role of oregonin, a diarylheptanoid, on proinflammatory responses in primary human macrophages and found that oregonin decreased cellular lipid accumulation and proinflammatory cytokine secretion. We also found that oregonin decreased ROS production in macrophages. Additionally, we observed that treatment of lipopolysaccharide-exposed macrophages with oregonin significantly induced the expression of antioxidant-related genes, including Heme oxygenase-1 and NADPH dehydrogenase quinone 1. In summary, we have shown that oregonin reduces lipid accumulation, inflammation and ROS production in primary human macrophages, indicating that oregonin has anti-inflammatory bioactivities.


Assuntos
Anti-Inflamatórios/farmacologia , Diarileptanoides/farmacologia , Lipídeos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Adulto , Alnus/química , Anti-Inflamatórios/química , Aterosclerose/tratamento farmacológico , Aterosclerose/imunologia , Células Cultivadas , Citocinas/imunologia , Diarileptanoides/química , Heme Oxigenase-1/genética , Humanos , Inflamação/tratamento farmacológico , Inflamação/imunologia , Lipopolissacarídeos/imunologia , Macrófagos/metabolismo , Espécies Reativas de Oxigênio/imunologia , Regulação para Cima/efeitos dos fármacos
8.
Phytochemistry ; 103: 178-187, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24703933

RESUMO

A series of diarylheptanoids, namely 1,7-bis-(3,4-dihydroxyphenyl)-heptan-3-one-5-O-D-xylopyranoside (oregonin), 1,7-bis-(3,4-dihydroxyphenyl)-3-hydroxyheptane-5-O-ß-D-xylopyranoside and 1,7-bis-(4-hydroxyphenyl)-heptane-3-one-5-O-ß-D-glucopyranoside (platyphylloside), were isolated from the bark of alder family trees, a species widely spread over in Europe. As antioxidants, these natural polyphenols have a promising potential in various fields of application, but their redox reactivity is insufficiently characterized. In this work, their antioxidant activity is described using assays based on DPPH and ABTS(+) radical scavenging, oxygen anion radicals (O2(-)) quenching. The standardized ORAC assay was also achieved, which measures the capacity to protect fluorescent molecules against oxidative degradation. The measured antioxidant activity was higher than that of the well-known antioxidant and biologically active diarylheptanoid curcumin. Molecular modeling was used to rationalize the differences in activity and the mechanisms of action. Thermodynamic descriptors mainly O-H bond dissociation enthalpies (BDEs) establish a clear structure-activity relationship.


Assuntos
Alnus/química , Antioxidantes/química , Diarileptanoides/química , Casca de Planta/química , Madeira/química , Relação Estrutura-Atividade
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