Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.045
Filtrar
1.
Life Sci ; 270: 119128, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33508299

RESUMO

Nanotechnology-based approaches have enabled overcoming the challenging issues such as the rapid clearance, poor solubility, and non-specific action or cellular uptake of drugs. In this study, we have evaluated the therapeutic effects of the phenolic compound, ferulic acid (FA), in the acute pancreatitis (AP) as this phenolic compound has demonstrated promising effects against the oxidative stress and inflammatory reactions. In order to overcome the poor solubility and bioavailability of FA, it was entrapped into the nanoparticles (NPs) based on the silk fibroin (SF) as a biomimetic substance. Neutrophil membrane-coated SF-NPs with appropriate capacity of FA loading and physicochemical characteristics, released FA in a controlled fashion, selectively delivered FA into the inflammatory pancreas lesion, and demonstrated protective effects against the detrimental aspects of the disease. The prepared nanoformulation by improving the pharmacological profile of FA and targeted delivery could be of therapeutic importance against the AP via suppressing the inflammation and oxidative stress.


Assuntos
Ácidos Cumáricos/farmacologia , Neutrófilos/química , Pancreatite/tratamento farmacológico , Animais , Disponibilidade Biológica , Ácidos Cumáricos/química , Ácidos Cumáricos/metabolismo , Sistemas de Liberação de Medicamentos , Fibroínas/química , Fibroínas/metabolismo , Fibroínas/farmacologia , Masculino , Nanopartículas/química , Neutrófilos/metabolismo , Pancreatite/metabolismo , Tamanho da Partícula , Ratos , Ratos Wistar
2.
Nat Commun ; 12(1): 459, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469030

RESUMO

Some Bacteroidetes and other human colonic bacteria can degrade arabinoxylans, common polysaccharides found in dietary fiber. Previous work has identified gene clusters (polysaccharide-utilization loci, PULs) for degradation of simple arabinoxylans. However, the degradation of complex arabinoxylans (containing side chains such as ferulic acid, a phenolic compound) is poorly understood. Here, we identify a PUL that encodes multiple esterases for degradation of complex arabinoxylans in Bacteroides species. The PUL is specifically upregulated in the presence of complex arabinoxylans. We characterize some of the esterases biochemically and structurally, and show that they release ferulic acid from complex arabinoxylans. Growth of four different colonic Bacteroidetes members, including Bacteroides intestinalis, on complex arabinoxylans results in accumulation of ferulic acid, a compound known to have antioxidative and immunomodulatory properties.


Assuntos
Proteínas de Bactérias/metabolismo , Bacteroides/enzimologia , Esterases/metabolismo , Microbioma Gastrointestinal/fisiologia , Xilanos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/ultraestrutura , Bacteroides/genética , Colo/microbiologia , Ácidos Cumáricos/metabolismo , Cristalografia por Raios X , Fibras na Dieta/metabolismo , Ensaios Enzimáticos , Esterases/genética , Esterases/isolamento & purificação , Esterases/ultraestrutura , Humanos , Mucosa Intestinal/microbiologia , Simulação de Dinâmica Molecular , Família Multigênica/genética , Especificidade por Substrato , Xilanos/química
3.
J Sci Food Agric ; 101(2): 548-554, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32673405

RESUMO

BACKGROUND: Ferulic acid is a natural occurring compound with antioxidant and antimicrobial bioactive properties, and recently was proposed as a new alternative growth promoter in meat-producing animals without changing meat quality parameters. The present study aimed to evaluate the impact of two doses of ferulic acid (FA) on the feedlot performance, carcass traits, and physicochemical and sensory characteristics of meat quality in commercial heifers. Ninety heifers (3/4 Bos taurus; n = 270; body weight = 480 ± 10 kg) were randomly assigned to one of the following treatments (30 days): Control, fed with a basal diet; FA250 or FA500 offered the same diet further supplemented with FA at 250 or 500 mg kg-1 feed, respectively. Feedlot performance, carcass traits, and physicochemical and meat sensory characteristics were evaluated. RESULTS: FA supplementation increased average daily gain (ADG) by 21%, hot carcass weight by 1.8% and cold carcass weight by 1.6% with respect to the control (P < 0.05). FA500 treatment caused a decrease (P < 0.05) in some carcass traits. However, carcass characteristics of economic importance, such as cold carcass dressing and LT muscle area, were improved by FA250 supplementation (P < 0.05), causing a possible growth promoter effect. Physicochemical and sensory parameters of meat were not altered by FA supplementation (P > 0.05). CONCLUSION: Ferulic acid has the potential for use as a growth promoter additive in finishing heifers without negatively affecting the meat quality, as occurs with some synthetic growth promotants compounds used in animal production. © 2020 Society of Chemical Industry.


Assuntos
Bovinos/crescimento & desenvolvimento , Ácidos Cumáricos/metabolismo , Suplementos Nutricionais/análise , Carne/análise , Ração Animal/análise , Animais , Bovinos/metabolismo , Feminino , Humanos , Masculino , Controle de Qualidade , Paladar
4.
J Sci Food Agric ; 101(2): 778-785, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32706119

RESUMO

BACKGROUND: Japanese dogwood (Cornus kousa Burg.) is a popular ornamental plant which develops edible compound fruit utilized in traditional Asian medicine. Previous compositional studies have focused on a small fraction of secondary metabolites at a single maturity stage. In order to address the question of optimal ripeness of Japanese dogwood fruit for consumption the study provides a comprehensive insight into its primary and secondary metabolic profile. RESULTS: The aim of the study was to investigate biochemical composition and morphological traits of Japanese dogwood (Cornus kousa Burg.) fruit at four maturity stages: GF, green fruit; BF, fruit with a defined red blush; RF, ripe fruit; OF, over-ripe fruit. Fruit was characterized by a nearly spherical shape, decreased water content in later stages of ripeness and highest a* values at RF and OF stages. Total sugars increased significantly from GF to OF stage and total organic acids and vitamin C decreased with maturation. Japanese dogwood fruit was characterized by four major phenolic groups: anthocyanins (three), flavonols (eight) hydroxycinnamic acids (three) and flavonoids (one) as well as by four lipophilic antioxidants: tocopherols (two), xanthophylls (five), carotenes (two) and chlorophylls (two). The progression of fruit ripening caused faster accumulation of individual phenolic compounds and lipophilic antioxidants which resulted in significantly higher total phenolic content at the RF and OF stages. CONCLUSION: Japanese dogwood fruit is a rich alternative source of ascorbic acid, α-tocopherol, flavonols and anthocyanins and should be consumed fresh at fully developed red colour of compound berries when their composition is optimal. © 2020 Society of Chemical Industry.


Assuntos
Cornus/crescimento & desenvolvimento , Frutas/química , Antocianinas/análise , Antocianinas/metabolismo , Antioxidantes/análise , Antioxidantes/metabolismo , Ácido Ascórbico/análise , Ácido Ascórbico/metabolismo , Carotenoides/análise , Carotenoides/metabolismo , Cornus/química , Cornus/metabolismo , Ácidos Cumáricos/análise , Ácidos Cumáricos/metabolismo , Flavonoides/análise , Flavonoides/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Fenóis/análise , Fenóis/metabolismo
5.
Nucleic Acids Res ; 49(1): 529-546, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33313837

RESUMO

A species-specific region, denoted SpG8-1b allowing hydroxycinnamic acids (HCAs) degradation is important for the transition between the two lifestyles (rhizospheric versus pathogenic) of the plant pathogen Agrobacterium fabrum. Indeed, HCAs can be either used as trophic resources and/or as induced-virulence molecules. The SpG8-1b region is regulated by two transcriptional regulators, namely, HcaR (Atu1422) and Atu1419. In contrast to HcaR, Atu1419 remains so far uncharacterized. The high-resolution crystal structures of two fortuitous citrate complexes, two DNA complexes and the apoform revealed that the tetrameric Atu1419 transcriptional regulator belongs to the VanR group of Pfam PF07729 subfamily of the large GntR superfamily. Until now, GntR regulators were described as dimers. Here, we showed that Atu1419 represses three genes of the HCAs catabolic pathway. We characterized both the effector and DNA binding sites and identified key nucleotides in the target palindrome. From promoter activity measurement using defective gene mutants, structural analysis and gel-shift assays, we propose N5,N10-methylenetetrahydrofolate as the effector molecule, which is not a direct product/substrate of the HCA degradation pathway. The Zn2+ ion present in the effector domain has both a structural and regulatory role. Overall, our work shed light on the allosteric mechanism of transcription employed by this GntR repressor.


Assuntos
Agrobacterium/metabolismo , Proteínas de Bactérias/fisiologia , Ácidos Cumáricos/metabolismo , Família Multigênica , Proteínas Repressoras/fisiologia , Agrobacterium/genética , Regulação Alostérica , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Sítios de Ligação , Cristalografia por Raios X , Regulação Bacteriana da Expressão Gênica , Genes Sintéticos , Modelos Moleculares , Regiões Promotoras Genéticas/genética , Conformação Proteica , Domínios Proteicos , Multimerização Proteica , Proteínas Repressoras/genética , Proteínas Repressoras/isolamento & purificação , Citrato de Sódio , Tetra-Hidrofolatos/fisiologia , Zinco/fisiologia
6.
PLoS One ; 15(9): e0239005, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946485

RESUMO

The two-domain bacterial laccases oxidize substrates at alkaline pH. The role of natural phenolic compounds in the oxidation of substrates by the enzyme is poorly understood. We have studied the role of ferulic and caffeic acids in the transformation of low molecular weight substrates and of soil humic acid (HA) by two-domain laccase of Streptomyces puniceus (SpSL, previously undescribed). A gene encoding a two-domain laccase was cloned from S. puniceus and over-expressed in Escherichia coli. The recombinant protein was purified by affinity chromatography to an electrophoretically homogeneous state. The enzyme showed high thermal stability, alkaline pH optimum for the oxidation of phenolic substrates and an acidic pH optimum for the oxidation of K4[Fe(CN)6] (potassium ferrocyanide) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt). Phenolic compounds were oxidized with lower efficiency than K4[Fe(CN)6] and ABTS. The SpSL did not oxidize 3.4-dimethoxybenzoic alcohol and p-hydroxybenzoic acid neither in the absence of phenolic acids nor in their presence. The enzyme polymerized HA-the amount of its high molecular weight fraction (>80 kDa) increased at the expense of low MW fraction (10 kDa). The addition of phenolic acids as potential mediators did not cause the destruction of HA by SpSL. In the absence of the HA, the enzyme polymerized caffeic and ferulic acids to macromolecular fractions (>80 kDa and 10-12 kDa). The interaction of SpSL with HA in the presence of phenolic acids caused an increase in the amount of HA high MW fraction and a two-fold increase in the molecular weight of its low MW fraction (from 10 to 20 kDa), suggesting a cross-coupling reaction. Infrared and solution-state 1H-NMR spectroscopy revealed an increase in the aromaticity of HA after its interaction with phenolic acids. The results of the study expand our knowledge on the transformation of natural substrates by two-domain bacterial laccases and indicate a potentially important role of the enzyme in the formation of soil organic matter (SOM) at alkaline pH values.


Assuntos
Lacase/metabolismo , Solo/química , Streptomyces/metabolismo , Ácidos Cafeicos/metabolismo , Clonagem Molecular/métodos , Ácidos Cumáricos/metabolismo , Substâncias Húmicas , Concentração de Íons de Hidrogênio , Cinética , Peso Molecular , Oxirredução , Proteínas Recombinantes/genética , Microbiologia do Solo , Streptomyces/genética , Especificidade por Substrato/genética
7.
PLoS One ; 15(4): e0231652, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32298342

RESUMO

Lemna species have been used in the food, feed, and pharmaceutical industries, as they are inexpensive sources of proteins, starches, and fatty acids. In this study, we treated L. paucicostata with different concentrations (0.05, 0.1, 0.2, 0.5, or 1 mM) of ethephon. The total dry weight decreased in all ethephon-treated groups compared to the control group. We also investigated the alteration of metabolic profiles induced by ethephon treatment by using gas chromatography-mass spectrometry. This analysis identified 48 metabolites, and the relative levels of most of alcohols, amino acids, fatty acids, and phenols increased by the ethephon treatment, whereas levels of organic acids and sugars decreased. Among these, the highest production of γ-aminobutyric acid (GABA, 5.041 ± 1.373 mg/L) and ferulic acid (0.640 ± 0.071 mg/L) was observed in the 0.5 mM and the 0.2 mM ethephon treatment groups, respectively. These results could be useful for large-scale culture of L. paucicostata with enhanced GABA and ferulic acid content for utilization in the food, feed, cosmetic, and pharmaceutical industries.


Assuntos
Araceae/crescimento & desenvolvimento , Ácidos Cumáricos/metabolismo , Compostos Organofosforados/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Ácido gama-Aminobutírico/metabolismo , Araceae/metabolismo , Metaboloma
8.
J Plant Physiol ; 248: 153136, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32120144

RESUMO

Elicited broccoli suspension-cultured cells (SCC) provide a useful system for obtaining bioactive compounds, including glucosinolates (GS) and phenolic compounds (PCs). In this work, coronatine (Cor) and methyl jasmonate (MJ) were used to increase the bioactive compound production in broccoli SCC. Although the use of Cor and MJ in secondary metabolite production has already been described, information concerning how elicitors affect cell metabolism is scarce. It has been suggested that Cor and MJ trigger defence reactions affecting the antioxidative metabolism. In the current study, the concentration of 0.5 µM Cor was the most effective treatment for increasing both the total antioxidant capacity (measured as ferulic acid equivalents) and glucosinolate content in broccoli SCC. The elicited broccoli SCC also showed higher polyphenol oxidase activity than the control cells. Elicitation altered the antioxidative metabolism of broccoli SCC, which displayed biochemical changes in antioxidant enzymes, a decrease in the glutathione redox state and an increase in lipid peroxidation levels. Furthermore, we studied the effect of elicitation on the protein profile and observed an induction of defence-related proteins. All of these findings suggest that elicitation not only increases bioactive compound production, but it also leads to mild oxidative stress in broccoli SCC that could be an important factor triggering the production of these compounds.


Assuntos
Acetatos/administração & dosagem , Aminoácidos/administração & dosagem , Antioxidantes/metabolismo , Brassica/metabolismo , Ciclopentanos/administração & dosagem , Glucosinolatos/metabolismo , Indenos/administração & dosagem , Oxilipinas/administração & dosagem , Compostos Fitoquímicos/metabolismo , Brassica/citologia , Ácidos Cumáricos/metabolismo , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Glutationa/metabolismo , Peroxidação de Lipídeos , Células Vegetais/metabolismo , Reguladores de Crescimento de Planta
9.
J Agric Food Chem ; 68(14): 4205-4214, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32141744

RESUMO

Polyphenol extracts derived from gastrointestinal digestates of buckwheat (Fagopyrum Mill) were studied for their intestinal transport and lipid-lowering effects in Caco-2/HepG2 coculture models. The relative amounts of all phenolic compounds throughout the digestion and intestinal absorption process were determined by UHPLC-Q-Orbitrap mass spectrometry. The digestible and easily transported phenolic compounds in buckwheat extract were identified. Herein, four main phenolic compounds and their metabolites were found on both the apical and basolateral sides of the Caco-2 cell transwell model. The transepithelial transport rates in the Caco-2 cell monolayer were scoparone (0.97) > hydroxycinnamic acid (0.40) > rutin (0.23) > quercetin (0.20). The main metabolism of hydroxycinnamic acid, quercetin, and scoparone in transepithelial transport was found to be methylation. Furthermore, results indicated that triglyceride, low-density lipoprotein cholesterol, total cholesterol, aspartate aminotransferase, and alanine aminotransferase levels in HepG2 cells on the basolateral side of coculture models can be suppressed by 53.64, 23.44, 36.49, 27.98, and 77.42% compared to the oleic acid-induced group (p < 0.05). In addition, the mRNA expression of Fabp4 relative to the control was found to be significantly upregulated (85.82 ± 10.64 to 355.18 ± 65.83%) by the easily transported buckwheat polyphenol components in HepG2 cells (p < 0.01).


Assuntos
Digestão , Fagopyrum/metabolismo , Extratos Vegetais/metabolismo , Polifenóis/metabolismo , Alanina Transaminase/metabolismo , Transporte Biológico , Células CACO-2 , Colesterol/metabolismo , LDL-Colesterol/metabolismo , Técnicas de Cocultura , Ácidos Cumáricos/metabolismo , Cumarínicos/metabolismo , Fagopyrum/química , Células Hep G2 , Humanos , Absorção Intestinal , Extratos Vegetais/química , Polifenóis/química , Quercetina/metabolismo , Rutina/metabolismo , Transaminases/metabolismo , Triglicerídeos/metabolismo
10.
Food Chem ; 317: 126346, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32070843

RESUMO

The inhibitory mechanisms of ferulic acid against α-amylase and α-glucosidase were investigated by enzyme kinetic analysis, circular dichroism (CD), Fourier-transform infrared (FT-IR) spectroscopy, fluorescence quenching and molecular docking. Results indicated that ferulic acid strongly inhibited α-amylase (IC50: 0.622 mg ml-1) and α-glucosidase (IC50: 0.866 mg ml-1) by mixed and non-competitive mechanisms, respectively. CD spectra and fluorescence intensity measurements confirmed that the secondary structure of α-amylase and α-glucosidase were changed and the microenvironments of certain amino acid residues were modulated by the binding of ferulic acid. FT-IR spectra indicated that the interaction between ferulic acid and α-amylase/α-glucosidase mainly involved in non-covalent bonds. Molecular docking further demonstrated that the interaction forces between ferulic acid and α-amylase/α-glucosidase were hydrogen bonds, with the binding energy of -5.30 to -5.10 and -5.70 kcal mol-1, respectively. This study might provide a theoretical basis for the designing of novel functional foods with ferulic acid.


Assuntos
Ácidos Cumáricos/metabolismo , Inibidores de Glicosídeo Hidrolases/metabolismo , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo , Sítios de Ligação , Ácidos Cumáricos/química , Inibidores de Glicosídeo Hidrolases/química , Ligação de Hidrogênio , Cinética , Simulação de Acoplamento Molecular , Estrutura Secundária de Proteína , Termodinâmica , alfa-Amilases/química , alfa-Glucosidases/química
11.
Food Chem ; 317: 126415, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32087518

RESUMO

This paper focused on improving antityrosinase ability of quercetin, cinnamic acid, and ferulic acid (named Q-CA-FA) from Asparagus by combining heating with ultrasound treatments. Fluorescence spectroscopy and UPLC-MS were used to evaluate inhibitory mechanisms. Results showed that the impacts of combining heating (150 °C for 30 min) with ultrasound (600 W for 30 min) treatments were similar to heating treatment (150 °C for 120 min) alone, and the inhibition rate could reach 98.2% in the addition of 5 mM Q-CA-FA. Fluorescence quenching indicated that treated Q-CA-FA-tyrosinase complex was more stable, but combining treatments did not change the major force between tyrosinase and polyphenols. Thermodynamic analysis illustrated that the randomness of compounds was also increased. Interestingly, 2-hydroxy-3-(3-hydroxy-4-methoxy-phenyl)-propionic acid 4-(2,3-dihydroxy-propyl)-phenyl ester was newly detected, which might be the major reason for enhancing antityrosinase ability. Taken together, these results provide a creative insight on increasing antityrosinase activity by combining heating with ultrasound treatments.


Assuntos
Monofenol Mono-Oxigenase/metabolismo , Polifenóis/metabolismo , Sonicação , Asparagus (Planta)/química , Asparagus (Planta)/metabolismo , Cromatografia Líquida de Alta Pressão , Cinamatos/análise , Cinamatos/metabolismo , Ácidos Cumáricos/análise , Ácidos Cumáricos/metabolismo , Temperatura Alta , Monofenol Mono-Oxigenase/antagonistas & inibidores , Polifenóis/análise , Quercetina/análise , Quercetina/metabolismo , Espectrometria de Fluorescência , Espectrometria de Massas em Tandem , Termodinâmica
12.
J Agric Food Chem ; 68(4): 1126-1135, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31891261

RESUMO

Phenylpropanoid (PPPN) compounds are widely used in agriculture, medical, food, and cosmetic industries because of their multiple bioactivities. Alternaria sp. MG1, an endophytic fungus isolated from grape, is a new natural source of PPPNs. However, the PPPN biosynthesis pathway in MG1 tends to be suppressed under normal growth conditions. Starvation has been reported to stimulate the PPPN pathway in plants, but this phenomenon has not been well studied in endophytic fungi. Here, metabolomics analysis was used to examine the profile of PPPN compounds, and quantitative reverse transcription-polymerase chain reaction was used to detect the expression of key genes in the PPPN biosynthesis pathway under starvation conditions. Starvation treatment significantly increased the accumulation of shikimate and PPPN compounds and upregulated the expression of key genes in their biosynthesis pathways. In addition to previously reported PPPNs, sinapate, 4-hydroxystyrene, piceatannol, and taxifolin were also detected under starvation treatment. These findings suggest that starvation treatment provides an effective way to optimize the production of PPPN compounds and may permit the investigation of compounds that are undetectable under normal conditions. Moreover, the diversity of its PPPNs makes strain MG1 a rich repository of valuable compounds and an extensive genetic resource for future studies.


Assuntos
Alternaria/metabolismo , Endófitos/metabolismo , Vitis/metabolismo , Vitis/microbiologia , Alternaria/genética , Alternaria/isolamento & purificação , Vias Biossintéticas , Ácidos Cumáricos/metabolismo , Endófitos/genética , Endófitos/isolamento & purificação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Metabolômica , Fenóis/metabolismo , Quercetina/análogos & derivados , Quercetina/biossíntese , Metabolismo Secundário , Estilbenos/metabolismo
13.
Molecules ; 25(2)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936386

RESUMO

Owing to their high surface area, stability, and functional groups on the surface, iron oxide hydroxide nanoparticles have attracted attention as enzymatic support. In this work, a chemometric approach was performed, aiming at the optimization of the horseradish peroxidase (HRP) immobilization process on Δ-FeOOH nanoparticles (NPs). The enzyme/NPs ratio (X1), pH (X2), temperature (X3), and time (X4) were the independent variables analyzed, and immobilized enzyme activity was the response variable (Y). The effects of the factors were studied using a factorial design at two levels (-1 and 1). The biocatalyst obtained was evaluated for the ferulic acid (FA) removal, a pollutant model. The materials were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The SEM images indicated changes in material morphology. The independent variables X1 (-0.57), X2 (0.71), and X4 (0.42) presented the significance effects estimate. The variable combinations resulted in two significance effects estimates, X1*X2 (-0.57) and X2*X4 (0.39). The immobilized HRP by optimized conditions (X1 = 1/63 (enzyme/NPs ratio, X2 = pH 8, X4 = 60 °C, and 30 min) showed high efficiency for FA oxidation (82%).


Assuntos
Enzimas Imobilizadas/metabolismo , Compostos Férricos/química , Peroxidase do Rábano Silvestre/metabolismo , Biocatálise , Ácidos Cumáricos/química , Ácidos Cumáricos/metabolismo , Peroxidase do Rábano Silvestre/ultraestrutura , Nanopartículas/química , Oxirredução , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
14.
Bull Environ Contam Toxicol ; 104(2): 200-205, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31781814

RESUMO

Phenoxy acid 2,4-D (2,4-dichlorophenoxy acid) is one of the most commonly-used herbicide in agriculture. Biodegradation of 2,4-D can be stimulated by structurally-related plant secondary metabolites such as ferulic acid (FA). The aim of this study is to: (1) assess the potential of indigenous soil bacteria to degrade 2,4-D in the presence of FA by PCR analysis of functional tfdA genes, (2) to determine the influence of 2,4-D and FA on samples ecotoxicity using Phytotoxkit® and Microtox® biotests. The detection of tfdA genes varied depending on the enrichment of samples with FA. FA suppressed detection of the tfdA genes, 100 µM 2,4-D induced higher detection of studied amplicons, while 500 µM 2,4-D delayed their detection. The ecotoxicity response was specific and differed between plants (PE% Lepidium sativum > Sinapis alba > Sorghum saccharatum) and bacteria (PE% up to 99% for Vibrio fischeri). Our findings confirm that 2,4-D and FA had a toxic influence on the used organisms.


Assuntos
Ácido 2,4-Diclorofenoxiacético/análise , Biodegradação Ambiental , Ácidos Cumáricos/análise , Herbicidas/análise , Poluentes do Solo/análise , Ácido 2,4-Diclorofenoxiacético/metabolismo , Aliivibrio fischeri/metabolismo , Ácidos Cumáricos/metabolismo , DNA Ribossômico/química , Genes Bacterianos , Herbicidas/metabolismo , Lepidium sativum/metabolismo , Extratos Vegetais , Sinapis/metabolismo , Solo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Sorghum/metabolismo
15.
Food Chem ; 310: 125823, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31757489

RESUMO

Phenolic acids, which are important aromatic secondary metabolites, are widely distributed in plant foods. In this study, a simple, economical and fast on-line immobilized trypsin microreactor was developed for evaluating the inhibitory activity of phenolic acids by capillary electrophoresis. The Michaelis-Menten constant (Km) of immobilized trypsin was determined as 0.99 mM, and the half-maximal inhibitory concentration (IC50) and inhibition constant (Ki) of benzamidine were measured as 3.39 and 1.68 mM, respectively. Then, the developed strategy was applied to investigate the inhibitory activity of six phenolic acids on trypsin. The results showed that gallic acid, caffeic acid and ferulic acid had high inhibitory activity at concentration of 150 µM. Molecular docking results illustrated that gallic acid, caffeic acid and ferulic acid can interact indirectly with the catalytic and substrate-binding sites of trypsin. The developed strategy is an effective tool for evaluating inhibitory activity of phenolic acids on trypsin.


Assuntos
Eletroforese Capilar/instrumentação , Enzimas Imobilizadas/metabolismo , Hidroxibenzoatos/metabolismo , Inibidores da Tripsina/farmacologia , Tripsina/metabolismo , Sítios de Ligação , Reatores Biológicos , Ácidos Cafeicos/química , Ácidos Cafeicos/metabolismo , Ácidos Cafeicos/farmacologia , Ácidos Cumáricos/química , Ácidos Cumáricos/metabolismo , Ácidos Cumáricos/farmacologia , Eletroforese Capilar/métodos , Enzimas Imobilizadas/química , Ácido Gálico/química , Ácido Gálico/metabolismo , Ácido Gálico/farmacologia , Hidroxibenzoatos/farmacologia , Simulação de Acoplamento Molecular , Tripsina/química , Inibidores da Tripsina/metabolismo
16.
Biochim Biophys Acta Proteins Proteom ; 1868(3): 140344, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31841665

RESUMO

In the context of increasing demand for renewable alternatives of fuels and chemicals, the valorization of lignin emerges as a value-adding strategy in biorefineries and an alternative to petroleum-derived molecules. One of the compounds derived from lignin is ferulic acid (FA), which can be converted into valuable molecules such as vanillin. In microorganisms, FA biotransformation into vanillin can occur via a two-step reaction catalyzed by the sequential activity of a feruloyl-CoA synthetase (FCS) and an feruloyl-CoA hydratase-lyase (FCHL), which could be exploited industrially. In this study, a prokaryotic FCHL derived from a lignin-degrading microbial consortium (named LM-FCHL) was cloned, successfully expressed in soluble form and purified. The crystal structure was solved and refined at 2.1 Å resolution. The LM-FCHL is a hexamer composed of a dimer of trimers, which showed to be quite stable under extreme pH conditions. Finally, small angle X-ray scattering corroborates the hexameric state in solution and indicates flexibility in the protein structure. The present study contributes to the field of lignin valorization to valuable molecules by establishing the biophysical and structural characterization for a novel FCHL member of unique characteristics.


Assuntos
Benzaldeídos/metabolismo , Ácidos Cumáricos/metabolismo , Hidroliases/química , Lignina/metabolismo , Acil Coenzima A/metabolismo , Hidroliases/metabolismo , Concentração de Íons de Hidrogênio , Consórcios Microbianos , Modelos Moleculares , Multimerização Proteica
17.
N Biotechnol ; 56: 38-45, 2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31731038

RESUMO

Wheat bran could be utilised as feedstock for innovative and sustainable biorefinery processes. Here, an enzymatic hydrolysis process for ferulic acid (FA) extraction was optimised step by step for total wheat bran (Tritello) and then also applied to the outer bran layer (Bran 1). Proteins, reducing sugars, total phenols and FA were quantified. The highest FA yields (0.82-1.05 g/kg bran) were obtained either by rehydrating the bran by autoclaving (Tritello) or by steam explosion (Bran 1) using a bran/water ratio of 1:20, followed by enzymatic pre-treatment with Alcalase and Termamyl, to remove protein and sugars, and a final enzymatic hydrolysis with Pentopan and feruloyl esterase to solubilise phenol. FA was recovered from the final digestate via solid phase extraction. A 40-fold scale-up was also performed and the release of compounds along all the process steps and at increasing incubation times was monitored. Results showed that FA was initially present at a minimum level while it was specifically released during the enzymatic treatment. In the final optimized process, the FA extraction yield was higher than that obtained with NaOH control hydrolysis while, in comparison with other FA enzymatic extraction methods, fewer process steps were required and no buffers, strong acid/alkali nor toxic compounds were used. Furthermore, the proposed process may be easily scaled-up, confirming the feasibility of wheat bran valorisation by biorefinery processes to obtain valuable compounds having several areas of potential industrial exploitation.


Assuntos
Ácidos Cumáricos/isolamento & purificação , Fibras na Dieta/metabolismo , Subtilisinas/metabolismo , alfa-Amilases/metabolismo , Ácidos Cumáricos/química , Ácidos Cumáricos/metabolismo , Hidrólise
18.
Appl Environ Microbiol ; 86(5)2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31862715

RESUMO

Phenolic acids are among the most abundant phenolic compounds in edible parts of plants. Lactic acid bacteria (LAB) metabolize phenolic acids, but the enzyme responsible for reducing hydroxycinnamic acids to phenylpropionic acids (HcrB) was only recently characterized in Lactobacillus plantarum In this study, heterofermentative LAB species were screened for their hydroxycinnamic acid metabolism. Data on strain-specific metabolism in combination with comparative genomic analyses identified homologs of HcrB as putative phenolic acid reductases. Par1 and HcrF both encode putative multidomain proteins with 25% and 63% amino acid identity to HcrB, respectively. Of these genes, par1 in L. rossiae and hcrF in L. fermentum were overexpressed in response to hydroxycinnamic acids. The deletion of par1 in L. rossiae led to the loss of phenolic acid metabolism. The strain-specific metabolism of phenolic acids was congruent with the genotype of lactobacilli; however, phenolic acid reductases were not identified in strains of Weissella cibaria that reduced hydroxycinnamic acids to phenylpropionic acids. Phylogenetic analysis of major genes involved in hydroxycinnamic acid metabolism in strains of the genus Lactobacillus revealed that Par1 was found to be the most widely distributed phenolic acid reductase, while HcrB was the least abundant, present in less than 9% of Lactobacillus spp. In conclusion, this study increased the knowledge on the genetic determinants of hydroxycinnamic acid metabolism, explaining the species- and strain-specific metabolic variations in lactobacilli and providing evidence of additional enzymes involved in hydroxycinnamic acid metabolism of lactobacilli.IMPORTANCE The metabolism of secondary plant metabolites, including phenolic compounds, by food-fermenting lactobacilli is a significant contributor to the safety, quality, and nutritional quality of fermented foods. The enzymes mediating hydrolysis, reduction, and decarboxylation of phenolic acid esters and phenolic acids in lactobacilli, however, are not fully characterized. The genomic analyses presented here provide evidence for three novel putative phenolic acid reductases. Matching comparative genomic analyses with phenotypic analysis and quantification of gene expression indicates that two of the three putative phenolic acid reductases, Par1 and HcrF, are involved in reduction of hydroxycinnamic acids to phenylpropionic acids; however, the activity of Par2 may be unrelated to phenolic acids and recognizes other secondary plant metabolites. These findings expand our knowledge on the metabolic potential of lactobacilli and facilitate future studies on activity and substrate specificity of enzymes involved in metabolism of phenolic compounds.


Assuntos
Ácidos Cumáricos/metabolismo , Lactobacillus/genética , Fermentação , Lactobacillus/metabolismo , Especificidade da Espécie , Weissella
19.
Prep Biochem Biotechnol ; 50(4): 341-348, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31809239

RESUMO

Ferulic acid is a fraction of the phenolics present in cereals such as rice and corn as a component of the bran. Substantial amounts of waste bran are generated by the grain processing industry and this can be valorized via extraction, purification and conversion of phenolics to value added chemical products. Alkaline alcohol based extracted and purified ferulic acid from corn bran was converted to vanillic acid using engineered Pseudomonas putida KT2440. The strain was engineered by rendering the vanAB gene nonfunctional and obtaining the mutant defective in vanillic acid metabolism. Biotransformation of ferulic acid using resting Pseudomonas putida KT2440 mutant cells resulted in more than 95 ± 1.4% molar yield from standard ferulic acid; while the corn bran derived ferulic acid gave 87 ± 0.38% molar yield. With fermentation time of less than 24 h the mutant becomes a promising candidate for the stable biosynthesis of vanillic acid at industrial scale.


Assuntos
Ácidos Cumáricos/metabolismo , Pseudomonas putida/metabolismo , Sementes/química , Ácido Vanílico/metabolismo , Zea mays/química , Ácidos Cumáricos/química , Fermentação
20.
J Biosci Bioeng ; 129(3): 322-326, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31672432

RESUMO

Factors affecting ferulic acid, ethyl ferulate and taste-active pyroglutamyl (pGlu) peptides levels in sake were analyzed using small-scale sake brewing tests on eighteen rice samples with differing cultivar variety, cropped year and area, and polishing rate. Ferulic acid concentration in sake was highly positively correlated with its content in rice (r = 0.782**, double asterisk indicates 1% significance level), feruloylesterase (FE) activity (r = 0.804**) and feruloylated saccharide forming activity (FSFA) (r = 0.619**) in the rice koji. The results suggested that ferulic acid in rice induced FE activity and FSFA, and these two enzymes accelerated the formation of ferulic acid in sake mash. The concentration of bitter-tasting peptides in sake was highly positively correlated with crude protein content in rice (r = 0.786**), and negatively correlated with acid carboxypeptidase (ACP) activity to (pGlu)LFGPNVNPWH (r = -0.612**), fermentation length (r = -0.820**), and pyroglutamyl leucine ((pGlu)L) concentration in sake (r = -0.502*; 5% significance level). The observation suggested that bitter-tasting peptides are initially formed in sake mash in accordance with protein content in rice, and are then hydrolyzed to smaller peptides, such as (pGlu)L. An ACP specific to the hydrolysis of bitter-tasting peptides was suggested by the observation that ACP activity to (pGlu)LFGPNVNPWH was significantly correlated (-0.612**) to their formation whereas an ACP to Cbz-Glu-Tyr was not (r = 0.220). It was suggested that (pGlu) oligo-peptide ethyl esters were formed during the decomposition of bitter-tasting peptides to which the ACP to (pGlu)LFGPNVNPWH might contribute.


Assuntos
Bebidas Alcoólicas/análise , Ácidos Cafeicos/análise , Ácidos Cumáricos/análise , Oryza/química , Peptídeos/análise , Ácidos Cafeicos/metabolismo , Ácidos Cumáricos/metabolismo , Fermentação , Hidrólise , Oryza/metabolismo , Peptídeos/metabolismo , Paladar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...