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1.
Talanta ; 236: 122874, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34635254

RESUMO

Herein, a one-pot alkali cutting-assisted synthesis approach has been developed to gain fluorescence (FL) tunable amino functionalized GQDs (NH2-GQDs), which exhibit concentration- and excitation-dependent FL behaviors, due to the self-assembled J-type aggregation effect and different electronic transitions governed by graphene basal plane and functional groups. While NH2-GQDs possess brighter FL emission than pristine GQDs, owning to the functionalization of amino groups with strong electron withdrawing ability. Particularly, the pH-dependent FL behavior of NH2-GQDs further reflects the FL emission mechanism originated from the intrinsic zigzag sites and introduced amino and carboxylic groups, which is available for pH sensing. Moreover, the NH2-GQDs also show a FL quenching upon reaction with tannic acid (TA), resulting in the construction of a FL turn-off TA sensing platform. A good linear relationship is obtained between logarithm of FL intensity (log F) and TA concentration in a linear dynamic range of 1-40 µM and a limit of detection of 43.3 nM (3σ/s, n = 9) is achieved, with a precision of 0.08% RSD at a concentration level of 5 µM (n = 9). This work features a simple and direct approach to acquire multifunctional nanosensor, providing great potential for further applications in chem/biosensing.


Assuntos
Grafite , Pontos Quânticos , Álcalis , Fluorescência , Concentração de Íons de Hidrogênio , Taninos
2.
Food Chem ; 366: 130632, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311235

RESUMO

The roles of total soluble polyphenols (TSP) and insoluble tannins (IST) in the enzymatic browning during the storage of dried persimmon slices packaged by different methods was studied. The color evolution was comprehensively evaluated within 18 weeks of storage, as well as determination the content variation of TSP, IST, and carotenoids. A series of simulated reactions were conducted to investigate the involvement of TSP and IST in PPO-catalyzed reaction. The results showed that N2-opaque packaging was a good way to alleviate this browning issue. The IST contributed preponderantly to the browning during the whole storage, while the contribution of TSP was little. And the degradation of carotenoids might be related to the color deterioration in the early storage. The IST participated in PPO-catalyzed reaction directly with the insoluble state. By contrast, only a small amount of TSP participated in PPO-catalyzed browning reaction, since it preferentially interacted with IST.


Assuntos
Diospyros , Carotenoides , Frutas , Reação de Maillard , Taninos
3.
Chemosphere ; 286(Pt 1): 131597, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34293568

RESUMO

Adsorbents reported for liquid phase decontamination under both aqueous and non-aqueous media are all dispersed phase sorbents that further require a tedious separation step post adsorption. Herein, a monolith, highly porous, and mechanically robust scaffold was synthesized for the adsorption of pollutants from both aqueous and non-aqueous media with facile separation and regeneration. Methylcellulose-tannic acid complex particles were prepared and systematically decorated on the surface of interpenetrating polymer network (IPN) scaffold via Pickering emulsion. Due to the surface coating of the particles, plausible amphiphilic adsorption of quinoline (QUI) and methylene blue (MB) was achieved from fuel and water, respectively. The hydroxyl (OH-) and carboxyl (COOH-) groups of tannic acid, alginate, and polyacrylic acid created hydrogen bonding, electrostatic interaction, acid-base interaction, and π-π stacking. Maximum adsorption capacity of 791.17 mg/g MB and 460.92 mg/g QUI was recorded with facile separation, excellent adsorbent regeneration, and reusability. Although both followed the pseudo-second-order adsorption kinetic model, a different mechanism was identified to govern the adsorption under aqueous and non-aqueous environment i.e. only the surface particles were active for QUI adsorption while the scaffold was also involved for MB adsorption.


Assuntos
Quinolinas , Poluentes Químicos da Água , Purificação da Água , Adsorção , Alginatos , Hidrogéis , Cinética , Metilcelulose , Azul de Metileno/análise , Taninos , Poluentes Químicos da Água/análise
4.
Chemosphere ; 286(Pt 1): 131626, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34346333

RESUMO

Extraction uranium from complicated aqueous solutions (seawater and nuclear wastewater) has been promoting the development of multi-functional adsorbents with high adsorption capacities and high selectivity. Here, we proposed a co-immobilization approach to preparing uranium adsorbents. Due to specific recognition and binding between functional groups, bayberry tannin (BT) and hydrous titanium oxide (HTO) were co-immobilized onto nano collagen fibrils (NCFs). The adsorption performances of NCFs-HTO-BT to uranium were systematically investigated in two aqueous systems, including nuclear wastewater and seawater. Results proved that NCFs-HTO-BT possessed the remarkable adsorption capacities and affinities for uranium in wastewater (393.186 mg g-1) and spiked seawater (14.878 mg g-1) with the uranium concentration of 320 mg g-1 and 8 mg g-1, respectively. Based on characteristic analysis of the adsorbent before and after uranium adsorption, the hydroxyl groups of HTO, the adjacent phenolic hydroxyl groups of BT, and nitrogen-containing and oxygen-containing functional groups of NCFs were active sites for uranium adsorption.


Assuntos
Myrica , Urânio , Adsorção , Água do Mar , Taninos , Titânio , Águas Residuárias
5.
J Colloid Interface Sci ; 606(Pt 2): 1457-1468, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492480

RESUMO

Multifunctional hydrogels with transparency, ultraviolet (UV)-blocking, stretchable, self-healing, adhesive, antioxidant and antibacterial properties are promising materials for biomedical and relevant applications. However, preparation of these hydrogels at ambient environment without stimuli is still a challenge. Here, a series of hydrogels possessing ultrashort gelation time (~30 s) at room or cold temperature were fabricated based on self-catalytic Fe3+/Tannic acid-cellulose nanofiber (Fe3+/TA-CNF). Fe3+/TA-CNF formed stable redox pairs to activate ammonium persulfate (initiator), generating abundant free radicals to trigger the ultrafast polymerization of acrylic acid (AA). To improve the antibacterial ability of hydrogel, a bilayer hydrogel composite (NF@HG) composed of tetracycline hydrochloride (TH)-loaded electrospun nanofibers and hydrogel layer was fabricated via a mild casting method. The NF@HG exhibited enhanced antibacterial ability and the sustained release of TH can provide long-term antibacterial activity. Besides, cell viability results demonstrated that NF@HG was non-cytotoxic. Taken together, this strategy based on self-catalytic Fe3+/TA-CNF system may inspire new aspects on fast and economical preparation of multifunctional hydrogels or composites, which have attractive industrial applications for biomedical materials.


Assuntos
Hidrogéis , Nanofibras , Antibacterianos/farmacologia , Catálise , Celulose , Taninos
6.
Sci Total Environ ; 806(Pt 1): 150518, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34583079

RESUMO

In this study, for the first time, we developed a series of co-graft tannin-based flocculants, TA-g-P(AM-DMDAAC), with different charge densities (CDs) and molecular weights (MWs) and evaluated their algal-removal performances. The effects of TA-g-P(AM-DMDAAC) on the cell integrity of Microcystis aeruginosa and release of extracellular organic matter (EOM) and microcystin-leucine-arginine (MC-LR) in flocculation and floc storage were also studied. Results suggested that TA-g-P(AM-DMDAAC) could not only efficiently remove algal cells over a wide pH range (pH 3-11) but also EOM. CD and MW significantly affected flocculation performance and floc characteristics of TA-g-P(AM-DMDAAC). A higher CD helped achieve a higher removal efficiency of algal cells and EOM, whereas a higher MW resulted in the formation of larger and more compact flocs. Furthermore, the larger and denser flocs could better protect algal cells and reduce the release of EOM during floc storage. Notably, algal cells in the TA-g-P(AM-DMDAAC) flocs did not appear to show signs of massive rupture nor did they release EOM and MC-LR extensively for at least 20 days of storage. The abundance and easy availability of tannin resources effectively reduce the cost of preparing tannin-based flocculants. Therefore, TA-g-P(AM-DMDAAC) can have broad application prospects in the management of cyanobacteria bloom.


Assuntos
Proliferação Nociva de Algas , Microcystis , Floculação , Peso Molecular , Taninos
7.
Food Chem ; 370: 131021, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34536784

RESUMO

Some bioactive compounds found in pulses (phytates, saponins, tannins) display antinutritional properties and interfere with fat-soluble vitamin bioavailability (i.e., bioaccessibility and intestinal uptake). As canned chickpeas are consumed widely, our aim was to optimize the chickpea canning process and assess whether this optimization influences fat-soluble vitamin bioavailability. Different conditions during soaking and blanching were studied, as was a step involving prior germination. Proteins, lipids, fibers, vitamin E, lutein, 5-methyl-tetrahydro-folate, magnesium, iron, phytates, saponins and tannins were quantified. Bioaccessibility and intestinal uptake of vitamin D and K were assessed using in vitro digestion and Caco-2 cells, respectively. Significant reductions of phytate, saponin and tannin contents (-16 to -44%), but also of folate content (up to -97%) were observed under optimized canning conditions compared with the control. However, bioaccessibility and cellular uptake of vitamin D and K remained unaffected after in vitro digestion of test meals containing control or optimized canned chickpeas.


Assuntos
Ácido Fítico , Vitaminas , Disponibilidade Biológica , Células CACO-2 , Digestão , Humanos , Taninos
8.
Chemosphere ; 286(Pt 2): 131705, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34333185

RESUMO

With regard to the treatment of multicomponent wastewaters, to construct multifunctional super-wetting membranes is highly attractive in current decade. In this work, a low-cost and novel NiFe2O4/TA/PVDF composite membrane was fabricated via a facile in-situ deposition method under vacuum system. In which, photo-response NiFe2O4 nanoparticles were immobilized on the surface of flexible PVDF base membrane via hydrophilic tannic acid (TA) as the binder. The resulting composite membrane exhibited a special superwettability of superamphilicity in air and underwater superoleophobicity with a nanoscale rough surface structure. One the one hand, NiFe2O4/TA/PVDF membrane can be used a reusable catalyst in Photo-Fenton degradation of organic dyes with high efficiency. On the other hand, the composite membrane can effectively separate emulsified oils from representative oil-in-water emulsions with excellent separation efficiency all above 99 % and relatively high flux (880-1525 Lm-2h-1 bar-1). More importantly, NiFe2O4/TA/PVDF composite membrane showed satisfactory processing efficiency, anti-fouling property and excellent reusability in deal with the mixed organic pollutants (water-insoluble emulsified oils and water-soluble organic dyes) existed in one aqueous system, which followed the procedure of initially photo-Fenton degradation of organic dyes emulsion and successively separation the remaining emulsion over the recovered membrane. This successful development of high-performance NiFe2O4/TA/PVDF composite membrane will provide a new candidate for both oil/water separation and organic wastewater treatment, as well as promote the utilization of spinel ferrites in the construction of multifunctional membrane for environmental purification.


Assuntos
Poluentes Ambientais , Membranas Artificiais , Polivinil , Taninos
9.
Chemosphere ; 287(Pt 3): 132199, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34555582

RESUMO

Herein, using dialdehyde waste paper (DAWP) as a cross-linking agent to immobilize persimmon tannin (PT) was first used to remove the U(VI) and Cr(VI) via the "waste control by waste" concept. The microscopic and macroscopic surface properties of the as-prepared adsorbent was characterized by the advanced characterization techniques. Factors that affected the elimination process such as variable pH, coexistence ions and equilibrium time were investigated by batch techniques. The results showed that the maximal removal capacities of U(VI) and Cr(VI) on DAWP-PT were 242.3 mg/g (pH = 6.0) and 178.7 mg/g (pH = 2.0) at 298 K, which exhibited competitiveness with most of the reported solid materials. Meanwhile, adsorption data were fitted perfectly to the Langmuir and Pseudo-second-order equations, which indicated that the monolayer and homogenous chemisorption dominated the removal process. The SEM-EDX, DFT and XPS analysis conformed that adsorption of U(VI) was mainly via surface complexation, while the elimination of Cr(VI) was a redox reaction process, and about 65.33% of Cr(III) and 34.67% of Cr(VI) co-existed onto the surface of DAWP-PT. Thus, this study would provide a high-efficiency and low-cost adsorbent for radionuclide and heavy metal treatment.


Assuntos
Diospyros , Poluentes Químicos da Água , Adsorção , Cromo/análise , Concentração de Íons de Hidrogênio , Cinética , Taninos , Poluentes Químicos da Água/análise
10.
Food Chem ; 371: 131168, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34601211

RESUMO

This research aims at predicting sensory properties generated by the phenolic fraction (PF) of grapes from chemical composition. Thirty-one grape extracts of different grape lots were obtained by maceration of grapes in hydroalcoholic solution; afterward they were submitted to solid phase extraction. The recovered PFs were reconstituted in a wine model. Subsequently the wine models, containing the PFs, were sensory (taste, mouthfeel) and chemically characterized. Significant sensory differences among the 31 PFs were identified. Sensory variables were predicted from chemical parameters by PLS-regression. Tannin activity and concentration along with mean degree of polymerization were found to be good predictors of dryness, while the concentration of large polymeric pigments seems to be involved in the "sticky" percept and flavonols in the "bitter" taste. Four fully validated PLS-models predicting sensory properties from chemical variables were obtained. Two out of the three sensory dimensions could be satisfactorily modeled. These results increase knowledge about grape properties and proposes the measurement of chemical variables to infer grape quality.


Assuntos
Vitis , Vinho , Taninos/análise , Paladar , Percepção Gustatória , Vinho/análise
11.
Food Chem ; 372: 131234, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34619522

RESUMO

Astringency is a dry puckering mouthfeel mainly generated by the binding of tannins with proteins in the mouth. Tannins confer benefits such as resistance to biotic stresses and have antioxidant activity, and moderate concentrations of tannins can improve the flavor of fruits or their products. However, fruits with high contents of tannins have excessive astringency, which is undesirable. Thus, the balance of astringency formation and removal is extremely important for human consumption of fruit and fruit-based products. In recent years, the understanding of fruit astringency has moved beyond the biochemical aspects to focus on the genetic characterization of key structural genes and their transcriptional regulators that cause astringency. This article provides an overview of astringency formation and evaluation. We summarize the methods of astringency regulation and strategies and mechanisms for astringency removal, and discuss perspectives for future exploration and modulation of astringency for fruit quality improvement.


Assuntos
Frutas , Vinho , Adstringentes , Frutas/química , Frutas/genética , Humanos , Taninos/análise , Paladar
12.
Food Chem ; 372: 131229, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34624784

RESUMO

Addition of oenological tannins claims to have a positive impact on wine stability, protection from oxidation and likely sensory persistence. However, their role on red wine aroma during oxidation is controversial. The present study aims at investigating the effect of addition of oenological tannins on wine flavour (mainly aroma) before and after air exposure. Temporal Dominance of Sensations, a dynamic sensory evaluation, was coupled with a dynamic chemical measurement (nosespace analysis) using a Proton-Transfer-Reaction Mass-Spectrometer connected to the nasal cavity of 17 assessors. Results showed that the oxidation of a non-oaked Pinot Noir red wine decreases the fruity aroma dominance and increases the maderised and prune one. A contextual decrease of the fruity ethyl decanoate and increase of oxidative Strecker aldehydes are observed. Ellagitannins but not proanthocyanidins preserved perception of fruitiness and prevented increase of maderised notes. Moreover, ellagitannins increase the aroma persistence mainly in the non-oxidized wine.


Assuntos
Odorantes , Vinho , Odorantes/análise , Percepção , Taninos , Paladar , Vinho/análise
13.
Braz. j. oral sci ; 20: e214034, jan.-dez. 2021. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1282553

RESUMO

Aim: To compare Enterococcus faecalis reduction after antimicrobial photodynamic therapy (aPDT) used with methylene blue, toluidine blue, tannin, and curcumin as photosensitizers, an adjunct to endodontic chemomechanical preparation (CMP) in root canals of human teeth. Methods: A total of 120 single-rooted teeth were divided into 6 groups (n = 20): G1- CMP and 2.5% sodium hypochlorite (NaOCl); G2- CMP and saline solution; G3- CMP, 2.5% NaOCl, and aPDT with 0.005% methylene blue; G4- CMP, 2.5% NaOCl, and aPDT with 0.005% toluidine blue; G5- CMP, 2.5% NaOCl, and aPDT with 0.005% tannin; and G6- CMP, 2.5% NaOCl, and aPDT with 0.005% curcumin. A portable semiconductor laser was used (660 nm, 100 mW, 1.8 J, 180s) in groups 1, 2, 3, 4, 5, and a blue LED light-curing (420-480 nm, 1200 mV/cm2 ) in G6. For all groups, a 5 min pre-irradiation time was applied. Samples were collected before (initial collection), immediately after (intermediate collection) and 7 days after CMP (final collection) for colony-forming unit (CFU) counting. The Kruskal-Wallis test and analysis of variance (ANOVA) were performed (p < 0.05; 95% confidence interval). Results: In between-group comparisons, there was no significant difference observed in the number of CFUs at the initial (p >< 0.001) and final collections (p >< 0.001) for G2 and G3. In within-group comparisons, the number of CFUs showed a decreasing trend in G4 (p = 0.007) and G5 (p = 0.001). Conclusion: Photosensitizers promoted E. faecalis reduction, with better results for tannin and curcumin. Alternative photosensitizers should be the focus of further studies.>< 0.05; 95% confidence interval). Results: In between-group comparisons, there was no significant difference observed in the number of CFUs at the initial (p < 0.001) and final collections (p >< 0.001) for G2 and G3. In within-group comparisons, the number of CFUs showed a decreasing trend in G4 (p = 0.007) and G5 (p = 0.001). Conclusion: Photosensitizers promoted E. faecalis reduction, with better results for tannin and curcumin. Alternative photosensitizers should be the focus of further studies.>< 0.001) and final collections (p < 0.001) for G2 and G3. In within-group comparisons, the number of CFUs showed a decreasing trend in G4 (p = 0.007) and G5 (p = 0.001). Conclusion: Photosensitizers promoted E. faecalis reduction, with better results for tannin and curcumin. Alternative photosensitizers should be the focus of further studies>< 0.001) for G2 and G3. In within-group comparisons, the number of CFUs showed a decreasing trend in G4 (p = 0.007) and G5 (p = 0.001). Conclusion: Photosensitizers promoted E. faecalis reduction, with better results for tannin and curcumin. Alternative photosensitizers should be the focus of further studies


Assuntos
Fotoquimioterapia , Taninos , Fármacos Fotossensibilizantes , Curcumina , Endodontia
14.
Anal Chim Acta ; 1186: 339122, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34756273

RESUMO

Developing a rapid and accurate method for tannic acid (TA) detection and measurement is necessary due to its extensive applications in the food industry. In this work, a fluorescence sensor with a low limit of detection was synthesized for TA for the first time. First, amine-modified carbon quantum dots (a-CQDs) with high-quantum yield were synthesized by the hydrothermal method. A layer of molecularly imprinted polymer (MIP) was then placed on a-CQDs by the surface printing method to increase the sensor selectivity. The mechanism of TA detection by the prepared a-CQDs/MIPs was quenching the fluorescence intensity of a-CQDs in the presence of TA due to the transfer of electrons from the TA to the a-CQDs. The linear range of the sensor response was at the TA concentration of 1-200 nmol L-1 and its detection limit was 0.6 nmol L-1 under optimal conditions. Finally, the sensor was used to measure TA in grape juice, green tea, and black tea samples using the recovery method. Recovery values between 97.4 and 103.6% and RSDs less than 3.8% indicated the high potential of the prepared sensor for TA analysis in complex food samples.


Assuntos
Impressão Molecular , Pontos Quânticos , Aminas , Carbono , Limite de Detecção , Polímeros Molecularmente Impressos , Taninos
15.
J Biomed Nanotechnol ; 17(10): 2043-2052, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34706804

RESUMO

A persimmon tannin-Aloe vera composite powder (PT-A) was investigated for its capacity to protect against ionizing radiation. Human hepatic cells (L02 cells) and human hepatoma cells (HepG2 cells) were pretreated with different concentrations of PT-A or the single compounds (PT or Aloe vera) and radiated with X-rays. After radiation and post-incubation for 12 h or 24 h, the cell viability, apoptosis, and reactive oxygen species (ROS) production were analyzed by Cell Counting Kit 8 (CCK-8), 2',7'-dichlorfluorescein diacetate (DCFH-DA) staining, and Hoechst 33258 staining/flow cytometry, respectively. CCK-8 results illustrated that the optimal radiation dose L02 cells was 8 Gy for L02 cells, and the cell activity was 71.72% (IC50 = 412.1 µg/mL) after post-radiation incubation of 12 h. For HepG2 cells, the optimal radiation dose was 8 Gy, and the cell activity was 62.37% (IC50 = 213.0 µg/mL). The cell apoptotic rate was the lowest at a PT-A concentration of 200 µg/mL in L02 cells (4.32%, P < 0.05), and at 100 µg/mL in HepG2 cells (9.80%, P < 0.05). ROS production induced by radiation could be effectively inhibited by 200 µg/mL of PT-A in L02 cells, and by 100 µg/mL of PT-A in HepG2 cells. The PT-A composite has good radioprotective effects on cell vitality and apoptosis of X-rays radiation exposure towards L02 cells and HepG2 cells compared to the persimmon tannin or Aloe vera. Therefore, PT-A composite might be useful as a natural, harmless anti-ionizing radiation agent, and has various clinical application prospects in future.


Assuntos
Aloe , Carcinoma Hepatocelular , Diospyros , Carcinoma Hepatocelular/tratamento farmacológico , Hepatócitos , Humanos , Taninos/farmacologia , Raios X
16.
J Agric Food Chem ; 69(42): 12445-12455, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34662108

RESUMO

Substantial efforts have been made in incorporating tannin-rich forages into grassland-based livestock production systems. However, the structural and functional diversity of tannins in different species limits their potential use at the field scale. We conducted a greenhouse experiment with 17 cultivars from 8 forage species and their cultivars. Ultraperformance liquid chromatography tandem mass spectrometry was used to analyze their polyphenolic profile and proanthocyanidin (PA) structural features in leaves. Our results highlight large inter- and intraspecies variability of plants in terms of polyphenol and tannin concentrations in the leaves. A concomitant and significant variation was also registered in the structural features of PA-rich forages such as the mean degree of polymerization and prodelphinidin percentage. The concentration of PA also varied within plant organs; the highest concentration was in flowers, but leaves had the highest contribution to harvestable PA biomass. Our research highlights that identifying these variations helps in identifying the representativeness of bioactivity and provides the basis for targeted breeding programs.


Assuntos
Proantocianidinas , Suplementos Nutricionais , Melhoramento Vegetal , Polifenóis , Taninos
17.
PLoS One ; 16(10): e0258607, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34648570

RESUMO

Staphylococcus aureus and Methicillin-resistant S. aureus (MRSA) remains one of the major concerns of healthcare associated and community-onset infections worldwide. The number of cases of treatment failure for infections associated with resistant bacteria is on the rise, due to the decreasing efficacy of current antibiotics. Notably, Acrophialophora levis, a thermophilous fungus species, showed antibacterial activity, namely against S. aureus and clinical MRSA strains. The ethyl acetate extract of culture filtrate was found to display significant activity against S. aureus and MRSA with a minimum inhibitory concentration (MIC) of 1 µg/mL and 4 µg/mL, respectively. Scanning electron micrographs demonstrated drastic changes in the cellular architecture of metabolite treated cells of S. aureus and an MRSA clinical isolate. Cell wall disruption, membrane lysis and probable leakage of cytoplasmic are hallmarks of the antibacterial effect of fungal metabolites against MRSA. The ethyl acetate extract also showed strong antioxidant activity using two different complementary free radicals scavenging methods, DPPH and ABTS with efficiency of 55% and 47% at 1 mg/mL, respectively. The total phenolic and flavonoid content was found to be 50 mg/GAE and 20 mg/CAE, respectively. More than ten metabolites from different classes were identified: phenolic acids, phenylpropanoids, sesquiterpenes, tannins, lignans and flavonoids. In conclusion, the significant antibacterial activity renders this fungal strain as a bioresource for natural compounds an interesting alternative against resistant bacteria.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Fatores Biológicos/farmacologia , Staphylococcus aureus Resistente à Meticilina/ultraestrutura , Sordariales/química , Acetatos/química , Antibacterianos/química , Antioxidantes/química , Fatores Biológicos/química , Flavonoides/isolamento & purificação , Hidroxibenzoatos/isolamento & purificação , Índia , Lignanas/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Sesquiterpenos/isolamento & purificação , Taninos/isolamento & purificação
18.
Poult Sci ; 100(12): 101479, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34700100

RESUMO

In 2 broiler trials, the effects of chestnut tannins on performance and meat quality (trial 1), and digestion (trial 2) were evaluated. In both trials, Ross 308 broilers received one of 2 basal diets: one basal diet contained corn and soy as main feed ingredients, while the challenge basal diet contained wheat, palm oil, and rapeseed meal. The composition of the basal diets was chosen to assess the interaction between chestnut tannins and diet composition. To both basal diets, chestnut tannins were added at 3 doses: 0 mg/kg (T-), 500 mg/kg (T+), or 2,000 mg/kg (T++), resulting in a total of 6 treatments. In trial 1, both basal diets containing 2,000 mg/kg chestnut tannins lowered broiler performance in grower and finisher phases. A tannin dose of 500 mg/kg had no effect on performance in either basal diet. Corn-based diets resulted in lower meat pH compared to wheat diets. Further, addition of chestnut tannins resulted in increased meat pH, and caused proportionally a lower meat drip loss and shear force for both basal diets. During the digestibility study (trial 2), blood was also collected. None of the treatments affected digestibility or blood parameters (glucose, non-esterified fatty acids, and triacylglycerols). Malondialdehyde (MDA) was measured in plasma to assess antioxidative properties of chestnut tannins. In wheat diets, chestnut tannins significantly lowered plasma MDA demonstrating its antioxidative nature. Regarding gut health, crypt depth decreased proportionally with the dosage of chestnut tannins in both basal diets with significantly shallower crypts for the wheat diets compared to the corn diets. Relative intestinal growth was stimulated in the wheat diets proportionally to the tannin dose based on the larger relative gut length. In conclusion, chestnut tannins did not influence digestive metabolism, yet they lowered performance at higher doses regardless of feed ingredients used in the diet. Tannins positively affected meat quality and when added to wheat diets, intestinal growth was stimulated and the antioxidative status of the broilers improved.


Assuntos
Galinhas , Taninos , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais , Digestão , Carne/análise , Nutrientes
19.
Molecules ; 26(19)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34641278

RESUMO

BACKGROUND: Caulerpa lentillifera (CL) is a green seaweed, and its edible part represents added value as a functional ingredient. CL was dried and extracted for the determination of its active compounds and the evaluation of its biological activities. The major constituents of CL extract (CLE), including tannic acid, catechin, rutin, and isoquercetin, exhibited beneficial effects, such as antioxidant activity, anti-diabetic activity, immunomodulatory effects, and anti-cancer activities in in vitro and in vivo models. Whether CLE has an anti-inflammatory effect and immune response remains unclear. METHODS: This study examined the effect of CLE on the inflammatory status and immune response of lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and the mechanisms involved therein. RAW264.7 cells were treated with different concentrations of CLE (0.1-1000 µg/mL) with or without LPS (1 µg/mL) for 24 h. Expression and production of the inflammatory cytokines, enzymes, and mediators were evaluated. RESULTS: CLE suppressed expression and production of the pro-inflammatory cytokines IL-6 and TNF-α. Moreover, CLE inhibited expression and secretion of the inflammatory enzyme COX-2 and the mediators PGE2 and NO. CLE also reduced DNA damage. Furthermore, CLE stimulated the immune response by modulating the cell cycle regulators p27, p53, cyclin D2, and cyclin E2. CONCLUSIONS: CLE inhibits inflammatory responses in LPS-activated macrophages by downregulating inflammatory cytokines and mediators. Furthermore, CLE has an immunomodulatory effect by modulating cell cycle regulators.


Assuntos
Anti-Inflamatórios/farmacologia , Catequina/farmacologia , Caulerpa/química , Quercetina/análogos & derivados , Rutina/farmacologia , Taninos/farmacologia , Animais , Catequina/isolamento & purificação , Citocinas/genética , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Imunidade/efeitos dos fármacos , Lipopolissacarídeos/efeitos adversos , Camundongos , Quercetina/isolamento & purificação , Quercetina/farmacologia , Células RAW 264.7 , Rutina/isolamento & purificação , Taninos/isolamento & purificação
20.
Food Res Int ; 149: 110663, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34600665

RESUMO

Sorghum is a potential substitute for corn/wheat in cereal-based extruded products. Despite agronomic advantages and its rich diversity of phenolic compounds, sorghum kafirins group together and form complex with tannins, leading to a low digestibility. Phenolic content/profile by UPLC-ESI-QTOF-MSE and kafirins polymerization by SE-HPLC were evaluated in wholemeal sorghum extrudates; tannin-rich (#SC319) and tannin-free (#BRS330) genotypes with/without turmeric powder. Total phenolic, proantocyanidin and flavonoid contents were strongly correlated with antioxidant capacity (r > 0.9, p < 0.05). Extrusion increased free (+60%) and decreased bound phenolics (-40%) in #SC319, but reduced both (-40%; -90%, respectively) in #BRS330, which presented lower abundance after extrusion. Turmeric addition did not significantly impact antioxidant activity, phenolic content and profile and kafirins profile. Tannins presence/absence impacted phenolic profiles and polymerization of kafirins which appears related to the thermoplastic process. The extrusion improved proteins solubility and can positively enhance their digestibility (phenolic compounds-proteins interactions), making more accessible to proteolysis in sorghum extrudates.


Assuntos
Sorghum , Curcuma , Grão Comestível/química , Fenóis/análise , Taninos
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