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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.
Molecules ; 28(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36677921

RESUMO

It has now been proven that many pathogens that cause infections and inflammation gradually mutate and become resistant to antibiotics. Chemically synthesized drugs treating inflammation most often only affect symptoms, but side effects could lead to the failure of human organs' functionality. On the other hand, plant-derived natural compounds have a long-term healing effect. It was shown that sea buckthorn (SBT) twigs are a rich source of biologically active compounds, including oligomeric proanthocyanidins (PACs). This study aimed to assess the anti-pathogenic and anti-inflammatory activity of water/ethanol extracts and PACs obtained from the lignocellulosic biomass of eight SBT cultivars. The anti-pathogenic activity of extracts and PACs was studied against pathogenic bacteria Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Bacillus cereus and fungus Candida albicans in 96-well plates by the two-fold serial broth microdilution method. The anti-bacterial activity of purified PACs was 4 and 10 times higher than for water and water/ethanol extracts, respectively, but the extracts had higher anti-fungal activity. Purified PACs showed the ability to reduce IL-8 and IL-6 secretion from poly-I:C-stimulated peripheral blood mononuclear cells. For the extracts and PACs of SBT cultivar 'Maria Bruvele' in the concentration range 0.0313-4.0 mg/mL, no toxic effect was observed.


Assuntos
Proantocianidinas , Humanos , Proantocianidinas/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Leucócitos Mononucleares , Bactérias , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antioxidantes/farmacologia , Etanol/farmacologia , Água/farmacologia , Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Testes de Sensibilidade Microbiana
3.
Materials (Basel) ; 15(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35683191

RESUMO

Toxic formaldehyde emissions, and the necessity to reduce the consumption of petrochemicals, stimulates the development of environmentally friendly adhesives. The aim of this research was to study, for the first time, the possibility of using condensed tannins (CTs)-rich extracts from grey alder (Alnus incana) and black alder (Alnus glutinosa) bark in the production of particleboards and plywood adhesives. The chemical structure, composition, and molecular weight of the CTs were identified by a 13C-NMR and TOF-MS analysis. Three innovative adhesive systems were studied: CTs-phenol-formaldehyde (CTs-PF) resin; a CTs-polyethyleneimine (PEI) adhesive system; and CTs-PEI combined with an ultra-low emitting formaldehyde resin (ULEFR)-CTs-PEI-ULEFR. The results showed that CTs-PF resin has properties close to commercial PF resin, and the formaldehyde emission was twice lower. CTs-PEI bonded particleboards corresponded to the requirements of the EN 312:2010 standard for particleboards in dry conditions (Type P2). CTs-PEI-ULEFR, with a 40-60% substitution of ULEFR by CTs-PEI, had adhesive properties very close to ULEFR; the plywood shear strength fit the requirements of the EN 314-2:1993 standard for application in internal and external system conditions. The introduction of extracted alder bark residues microparticles into the composition of the adhesive system showed their positive potential for application as a filler.

4.
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.

5.
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.

6.
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
7.
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
8.
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).

9.
J Enzyme Inhib Med Chem ; 33(1): 1055-1063, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29877148

RESUMO

Oregonin is an open-chain diarylheptanoid isolated from Alnus incana bark that possesses remarkable antioxidant and anti-inflammatory properties, inhibits adipogenesis, and can be used in the prevention of obesity and related metabolic disorders. Here, we aimed to investigate the effects of oregonin on the epigenetic regulation in cells as well as its ability to modulate DNA methylating enzymes expression and mitochondrial DNA (mtDNA) copies. Our results show that oregonin altered the expression of DNA methyltransferases and mtDNA copy numbers in dependency on concentration and specificity of cells genotype. A close correlation between mtDNA copy numbers and mRNA expression of the mtDnmt1 and Dnmt3b was established. Moreover, molecular modeling suggested that oregonin fits the catalytic site of DNMT1 and partially overlaps with binding of the cofactor. These findings further extend the knowledge on oregonin, and elucidate for the first time its potential to affect the key players of the DNA methylation process, namely DNMTs transcripts and mtDNA.


Assuntos
Alnus/química , DNA (Citosina-5-)-Metiltransferase 1/biossíntese , DNA (Citosina-5-)-Metiltransferases/biossíntese , DNA Mitocondrial/metabolismo , Diarileptanoides/farmacologia , Fibroblastos/efeitos dos fármacos , Casca de Planta/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA/efeitos dos fármacos , Diarileptanoides/química , Diarileptanoides/isolamento & purificação , Relação Dose-Resposta a Droga , Camundongos , Estrutura Molecular , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Relação Estrutura-Atividade , DNA Metiltransferase 3B
10.
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
11.
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
12.
Environ Technol ; 33(10-12): 1427-33, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22856318

RESUMO

Meat processing grease wastes were composted with lignocellulosic material. Judging by the reduction in the yield of compost lipophilic extract, grease was degraded during the first 20 days of composting. Compost humic acids (HA) and fulvic acids (FA) were characterized by elemental analysis, Fourier transform infrared (FT-IR) spectroscopy and analytical pyrolysis. The compost HA and FA fractions contained a ligno-protein complex. The presence of grease (6.7% dry weight) during composting had a slight influence on the chemical composition of HA and FA. Analytical pyrolysis indicated that, during composting, major changes were observed in the FA fraction, namely, the proportion of nitrogen-bearing compounds increased and carbohydrate-derived products decreased drastically in the final compost. In addition, the shortening of the aliphatic chains of lignin-derived compounds was observed with an increase in the C6C(0-2)/C6C3 ratio in pyrolysates.


Assuntos
Benzopiranos/análise , Substâncias Húmicas/análise , Lignina/química , Indústria de Embalagem de Carne , Reciclagem , Animais , Gorduras/química , Cromatografia Gasosa-Espectrometria de Massas , Resíduos Industriais , Poaceae , Solo/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Madeira
13.
Bioresour Technol ; 95(3): 309-17, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15288274

RESUMO

The present work is devoted to studies of the radical scavenging properties of lignins, which are recognized as efficient antioxidants of natural origin. Radical scavenging efficiency of a series of lignins isolated from deciduous and coniferous wood species and 10 lignin related monomeric compounds were examined against 1,1-diphenyl-2-picrylhydrazyl (DPPH*) radical in homogeneous conditions using ESR and spectrophotometry methods. Some structure-activity relationships are proposed, pointing out the importance of the non-etherified OH phenolic groups, ortho-methoxy groups, hydroxyl groups and the double bond between the outermost carbon atoms in the side chain for increasing scavenger activity. Analysis of rate constants for the lignins-DPPH* interaction revealed the contribution of polymer molecular weight and pi-polyconjugation systems. The pi-conjugation systems of lignins operate as catalysts/activators of the interaction with DPPH*. Heterogeneity in terms of component composition (carbohydrate admixtures) and polydispersity is the factor which can decrease drastically the antioxidant efficiency of isolated lignins. The connection of the antibacterial effect of kraft lignin with radical scavenging activity of its soluble fraction was assumed.


Assuntos
Antioxidantes/farmacologia , Sequestradores de Radicais Livres/farmacologia , Lignina/farmacologia , Avaliação Pré-Clínica de Medicamentos , Lignina/análogos & derivados , Solubilidade , Relação Estrutura-Atividade , Árvores/química
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