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1.
Food Chem ; 448: 139073, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574713

RESUMO

This study reported for the first time that Ascorbic acid (AA) could appreciably boost the efficiency of Octyl gallate (OG)-mediated photodynamic inactivation (PDI) on Escherichia coli and Staphylococcus aureus in planktonic and biofilm states. The combination of OG (0.075 mM) and AA (200 mM) with 420 nm blue light (212 mW/cm2) led to a >6 Log killing within only 5 min for E. coli and S. aureus and rapid eradication of biofilms. The mechanism of action appears to be the generation of highly toxic hydroxyl radicals (•OH) via photochemical pathways. OG was exposed to BL irradiation to generate various reactive oxygen radicals (ROS) and the addition of AA could transform singlet oxygen (1O2) into hydrogen peroxide (H2O2), which could further react with AA to generate enormous •OH. These ROS jeopardized bacteria and biofilms by nonspecifically attacking various biomacromolecules. Overall, this PDI strategy provides a powerful microbiological decontamination modality to guarantee safe food products.


Assuntos
Ácido Ascórbico , Biofilmes , Escherichia coli , Ácido Gálico , Ácido Gálico/análogos & derivados , Luz , Staphylococcus aureus , Biofilmes/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Ácido Ascórbico/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Ácido Gálico/farmacologia , Ácido Gálico/química , Escherichia coli/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Antibacterianos/farmacologia , Antibacterianos/química , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Plâncton/efeitos dos fármacos , Plâncton/efeitos da radiação , Luz Azul
2.
Mol Pharm ; 21(5): 2577-2589, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38647021

RESUMO

This study aimed to repurpose the antifungal drug flucytosine (FCN) for anticancer activity together with cocrystals of nutraceutical coformers sinapic acid (SNP) and syringic acid (SYA). The cocrystal screening experiments with SNP resulted in three cocrystal hydrate forms in which two are polymorphs, namely, FCN-SNP F-I and FCN-SNP F-II, and the third one with different stoichiometry in the asymmetric unit (1:2:1 ratio of FCN:SNP:H2O, FCN-SNP F-III). Cocrystallization with SYA resulted in two hydrated cocrystal polymorphs, namely, FCN-SYA F-I and FCN-SYA F-II. All the cocrystal polymorphs were obtained concomitantly during the slow evaporation method, and one of the polymorphs of each system was produced in bulk by the slurry method. The interaction energy and lattice energies of all cocrystal polymorphs were established using solid-state DFT calculations, and the outcomes correlated with the experimental results. Further, the in vitro cytotoxic activity of the cocrystals was determined against DU145 prostate cancer and the results showed that the FCN-based cocrystals (FCN-SNP F-III and FCN-SYA F-I) have excellent growth inhibitory activity at lower concentrations compared with parent FCN molecules. The prepared cocrystals induce apoptosis by generating oxidative stress and causing nuclear damage in prostate cancer cells. The Western blot analysis also depicted that the cocrystals downregulate the inflammatory markers such as NLRP3 and caspase-1 and upregulate the intrinsic apoptosis signaling pathway marker proteins, such as Bax, p53, and caspase-3. These findings suggest that the antifungal drug FCN can be repurposed for anticancer activity.


Assuntos
Antifúngicos , Antineoplásicos , Apoptose , Reposicionamento de Medicamentos , Flucitosina , Neoplasias da Próstata , Transdução de Sinais , Apoptose/efeitos dos fármacos , Humanos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Antifúngicos/farmacologia , Antifúngicos/química , Masculino , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Reposicionamento de Medicamentos/métodos , Flucitosina/farmacologia , Flucitosina/química , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Ácido Gálico/química , Ácido Gálico/farmacologia , Ácido Gálico/análogos & derivados , Cristalização , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
3.
Environ Pollut ; 349: 123917, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38583794

RESUMO

Phthalate esters (PAEs) are plasticizers widely used in the industry and easily released into the environment, posing a serious threat to human health. Molecularly imprinted polymers (MIPs) are important as selective adsorbents for the removal of PAEs. In this study, three kinds of mussel-inspired MIPs for the removal of PAEs were first prepared with gallic acid (GA), hexanediamine (HD), tannic acid (TA), and dopamine (DA) under mild conditions. The adsorption results showed that the MIP with low cost derived from GA and HD (GAHD-MIP) obtained the highest adsorption capacity among these materials. Furthermore, 97.43% of equilibrium capacity could be reached within the first 5 min of adsorption. Especially, the dummy template of diallyl phthalate (DAP) with low toxicity was observed to be more suitable to prepare MIPs than dibutyl phthalate (DBP), although DBP was the target of adsorption. The adsorption process was in accordance with the pseudo-second-order kinetics model. In the isotherm analysis, the adsorption behavior agreed with the Freundlich model. Additionally, the material maintained high adsorption performance after 7 cycles of regeneration tests. The GAHD-MIP adsorbents in this study, with low cost, rapid adsorption equilibrium, green raw materials, and low toxicity dummy template, provide a valuable reference for the design and development of new MIPs.


Assuntos
Dibutilftalato , Ácido Gálico , Polímeros Molecularmente Impressos , Poluentes Químicos da Água , Adsorção , Dibutilftalato/química , Poluentes Químicos da Água/química , Ácido Gálico/química , Polímeros Molecularmente Impressos/química , Ácidos Ftálicos/química , Cinética , Purificação da Água/métodos
4.
Food Chem ; 449: 139273, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38599110

RESUMO

The objectives of this study were to modify hordein with gallic acid (GA) in alcohol-free media and to compare the impact of covalent and non-covalent binding on the properties of hordein. Covalent hordein-GA complexes (H-GA) and non-covalent hordein/GA complexes (H/GA) were distinguished by molecular weight, free sulfhydryl groups and free amino groups. Isothermal titration calorimetry (ITC) demonstrated that physical mixing induced non-covalent binding of GA to hordein via hydrogen bonding and hydrophobic interactions, with a lower binding efficiency than covalent ones. Both complexation types led to a structural shift of hordein toward disorder, while grafting of oligomeric GA and alkaline treatment resulted in lower surface hydrophobicity and higher antioxidant activity of H-GA compared to H/GA. The nanoparticles assembled from H-GA had smaller particle sizes and higher physical stability than those formed from H/GA. The results of this study may provide new insights into the modification of hordein by polyphenols.


Assuntos
Ácido Gálico , Ácido Gálico/química , Interações Hidrofóbicas e Hidrofílicas , Ligação de Hidrogênio , Tamanho da Partícula , Antioxidantes/química , Nanopartículas/química , Estrutura Molecular , Etanol/química
5.
Chemosphere ; 357: 142100, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657697

RESUMO

Emulsified oils and dye contaminants already pose a huge threat to global ecosystems and human health. It is a significant research topic to develop efficient, rapid, versatile methods for emulsion separation and dye adsorption. The membrane material modified with common methods only modified the outer surface of the membrane, while the interior is hardly fully decorated. In this investigation, a solvent exchange method was used to in situ grow nanoparticles in the interior of a porous sponge. These nanoparticles were obtained with polyethyleneimine, gallic acid, and tannic acid via Michael addition and Schiff base reaction. The prepared nanoparticle-coated sponges provided efficient separation of dyes, emulsions, and complex contaminants. The separation efficiency of the dye reached 99.49%, and the separation efficiency of the emulsion was as high as 99.87% with a flux of 11140.3 L m-2 h-1. Furthermore, the maximum adsorption capacity reached 486.8 mg g-1 for cationic dyes and 182.1 mg g-1 for anionic dyes. More importantly, the nanoparticles were highly robust on the surface of the porous sponge, and the modified sponge could have long-term applications in hazardous environments. Overall, it is envisioned that the nanoparticles-modified porous sponge exhibited considerable potential for emulsion and dye wastewater treatment.


Assuntos
Corantes , Emulsões , Nanopartículas , Poluentes Químicos da Água , Corantes/química , Adsorção , Emulsões/química , Nanopartículas/química , Porosidade , Poluentes Químicos da Água/química , Taninos/química , Águas Residuárias/química , Purificação da Água/métodos , Ácido Gálico/química , Polietilenoimina/química
6.
Int J Biol Macromol ; 267(Pt 2): 131626, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631590

RESUMO

Self-healing hydrogel is a promising soft material for applications in wound dressings, drug delivery, tissue engineering, biomimetic electronic skin, and wearable electronic devices. However, it is a challenge to fabricate the self-healing hydrogels without external stimuli. Inspired by mussel, the metal-catechol complexes were introduced into the hydrogel systems to prepare the mussel-inspired hydrogels by regulating the gelation kinetics of Fe3+ crosslinkers with gallic acid (GA) in this research. The amine-functionalized carboxymethyl cellulose (CMC) was grafted with GA and then chelated with Fe3+ to form a multi-response system. The crosslinking of carboxymethyl cellulose-ethylenediamine-gallic acid (CEG) hydrogel was controlled by adjusting the pH to affect the iron coordination chemistry, which could enhance the self-healing properties and mechanical strength of hydrogels. In addition, the CEG hydrogel exhibited great antibacterial and antioxidant properties. And the CEG hydrogel could strongly adhere to the skin tissue. The adhesion strength of CEG hydrogel on pigskin was 11.44 kPa, which is higher than that of commercial wound dressings (∼5 kPa). Moreover, the thixotropy of the CEG hydrogel was confirmed with rheological test. In summary, it has great potential in the application field of wound dressing.


Assuntos
Carboximetilcelulose Sódica , Ácido Gálico , Hidrogéis , Ácido Gálico/química , Hidrogéis/química , Hidrogéis/farmacologia , Carboximetilcelulose Sódica/química , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Ferro/química , Suínos , Reagentes de Ligações Cruzadas/química , Reologia , Cicatrização/efeitos dos fármacos
7.
Nat Commun ; 15(1): 3539, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38670975

RESUMO

Bergenin, a rare C-glycoside of 4-O-methyl gallic acid with pharmacological properties of antitussive and expectorant, is widely used in clinics to treat chronic tracheitis in China. However, its low abundance in nature and structural specificity hampers the accessibility through traditional crop-based manufacturing or chemical synthesis. In the present work, we elucidate the biosynthetic pathway of bergenin in Ardisia japonica by identifying the highly regio- and/or stereoselective 2-C-glycosyltransferases and 4-O-methyltransferases. Then, in Escherichia coli, we reconstruct the de novo biosynthetic pathway of 4-O-methyl gallic acid 2-C-ß-D-glycoside, which is the direct precursor of bergenin and is conveniently esterified into bergenin by in situ acid treatment. Moreover, further metabolic engineering improves the production of bergenin to 1.41 g L-1 in a 3-L bioreactor. Our work provides a foundation for sustainable supply of bergenin and alleviates its resource shortage via a synthetic biology approach.


Assuntos
Benzopiranos , Vias Biossintéticas , Escherichia coli , Engenharia Metabólica , Benzopiranos/metabolismo , Benzopiranos/química , Engenharia Metabólica/métodos , Escherichia coli/metabolismo , Escherichia coli/genética , Glicosiltransferases/metabolismo , Metiltransferases/metabolismo , Ácido Gálico/metabolismo , Ácido Gálico/química , Reatores Biológicos , Glicosídeos/biossíntese , Glicosídeos/metabolismo , Glicosídeos/química
8.
Int J Biol Macromol ; 266(Pt 2): 131360, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38580017

RESUMO

A humic acid-gelatin (HA-Gel) hydrogel, a gallic acid-xanthan gum (GA-XG) hydrogel, a HA-Gel/GA-XG hydrogel, and superabsorbent polymer (SAP) of HA-Gel/GA-XG/polyacrylamide (PAM) hydrogel were synthesized using electron beam irradiation method. The capability of synthesized hydrogels in loading and controlled release of fulvic acid (FA) was studied. The chemical and physical structure of sorbents was confirmed by various analyses. The effect of irradiation dose on mechanical properties, gel percentage, swelling, and absorbency under load (AUL) of the sorbents was investigated. By changing the hydrogel structures into the SAP form, its swelling capacity was increased from 37 to 320 g/g. Both hybrid hydrogel and SAP were reusable for up to 7 cycles. The maximum fertilizer loading capacities for SAP and hybrid hydrogel were 402.1 and, 175.5 mg g-1, respectively. In comparison to hydrogels, the SAP showed a slower FA-release performance. Thus, in soil media, 86 % of FA was released in 15-20 days from the hybrid hydrogel while with the SAP, 81 % of FA was released in 30-35 days. The significant improvement in the growth of fodder corn treated with FA-loaded SAP in the greenhouse media in comparison to the control groups showed the effective performance of the designed SAP, favoring its practical applications.


Assuntos
Benzopiranos , Gelatina , Hidrogéis , Polissacarídeos Bacterianos , Zea mays , Hidrogéis/química , Benzopiranos/química , Polissacarídeos Bacterianos/química , Gelatina/química , Zea mays/química , Preparações de Ação Retardada/química , Elétrons , Polímeros/química , Fertilizantes , Ácido Gálico/química , Substâncias Húmicas
9.
Food Chem ; 447: 139029, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38513480

RESUMO

Hydrocolloids synthesized by gallic acid (GA) and ferulic acid (FA) grafting onto chitosan (CS) were characterized, and their effects on PhIP formation in pan-fried golden pompano were investigated. Spectrograms including nuclear magnetic resonance, Fourier transform infrared spectroscopy and ultraviolet-visible confirmed that GA and FA were successfully grafted onto CS via covalent bonds, with grafting degree of 97.06 ± 2.56 mg GA/g and 93.56 ± 2.76 mg FA/g, respectively. The CS-g-GA and CS-g-FA exerted better solubility and antioxidant activities than CS. For the 8-min pan-fried golden pompano fillets, CS-g-GA and CS-g-FA (0.5 %, m/v) significantly reduced the PhIP formation by 61.71 % and 81.64 %, respectively. Chemical models revealed that CS-g-GA and CS-g-FA inhibited PhIP formation mainly by decreasing the phenylacetaldehyde contents from Maillard reaction and competing with creatinine to react with phenylacetaldehyde. Therefore, it was suggested that CS-g-phenolic acids emerge as novel coating for aquatic products during processing and inhibit heterocyclic amines generation.


Assuntos
Acetaldeído/análogos & derivados , Quitosana , Imidazóis , Quitosana/química , Polifenóis , Antioxidantes/química , Ácido Gálico/química
10.
Biochemistry (Mosc) ; 89(1): 173-183, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38467553

RESUMO

Natural polyphenols are promising compounds for the pharmacological control of oxidative stress in various diseases. However, low bioavailability and rapid metabolism of polyphenols in a form of glycosides or aglycones have stimulated the search for the vehicles that would provide their efficient delivery to the systemic circulation. Conjugation of polyphenols with cationic amphiphilic peptides yields compounds with a strong antioxidant activity and ability to pass through biological barriers. Due to a broad range of biological activities characteristic of polyphenols and peptides, their conjugates can be used in the antioxidant therapy, including the treatment of viral, oncological, and neurodegenerative diseases. In this work, we synthesized linear and dendrimeric cationic amphiphilic peptides that were then conjugated with gallic acid (GA). GA is a non-toxic natural phenolic acid and an important functional element of many flavonoids with a high antioxidant activity. The obtained GA-peptide conjugates showed the antioxidant (antiradical) activity that exceeded 2-3 times the antioxidant activity of ascorbic acid. GA attachment had no effect on the toxicity and hemolytic activity of the peptides. GA-modified peptides stimulated the transmembrane transfer of the pGL3 plasmid encoding luciferase reporter gene, although GA attachment at the N-terminus of peptides reduced their transfection activity. Several synthesized conjugates demonstrated the antibacterial activity in the model of Escherichia coli Dh5α growth inhibition.


Assuntos
Antioxidantes , Polifenóis , Antioxidantes/farmacologia , Antioxidantes/química , Polifenóis/farmacologia , Polifenóis/química , Peptídeos/farmacologia , Peptídeos/química , Ácido Gálico/farmacologia , Ácido Gálico/química , Antibacterianos/química
11.
Food Res Int ; 178: 113943, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38309869

RESUMO

Formation of starch-polyphenol complexes by high pressure homogenization (HPH) is widely used to reduce starch digestibility and delay the postprandial glycemic response, thereby benefiting obesity and associated metabolic diseases. This study investigated the effect of complexation temperature on multi-scale structures, physicochemical and digestive properties of pea starch-gallic acid (PS-GA) complexes during HPH process, while also elucidating the corresponding molecular mechanism regulating in vitro digestibility. The results demonstrated that elevating complexation temperature from 30 °C to 100 °C promoted the interaction between PS and GA and reached a peak complex index of 9.22 % at 90 °C through non-covalent binding. The enhanced interaction led to the formation of ordered multi-scale structures within PS-GA complexes, characterized by larger particles that exhibited greater thermal stability and elastic properties. Consequently, the PS-GA complexes exhibited substantially reduced digestion rates with the content of resistant starch increased from 28.50 % to 38.26 %. The potential molecular mechanism underlying how complexation temperature regulated digestibility of PS-GA complexes might be attributed to the synergistic effect of the physical barriers from newly ordered structure and inhibitory effect of GA against digestive enzymes. Overall, our findings contribute to the advancement of current knowledge regarding starch-polyphenol interactions and promote the development of functional starches with low postprandial glycemic responses.


Assuntos
Pisum sativum , Amido , Amido/química , Temperatura , Ácido Gálico/química , Digestão , Polifenóis
12.
Biomater Sci ; 12(6): 1405-1424, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38372381

RESUMO

Polyphenol hydrogels have garnered widespread attention due to their excellent adhesion, antioxidant, and antibacterial properties. Gallic acid (GA) is a typical derivative of pyrogallol that is used as a hydrogel crosslinker or bioactive additive and can be used to make multifunctional hydrogels with properties superior to those of widely studied catechol hydrogels. Furthermore, compared to polymeric tannic acid, gallic acid is more suitable for chemical modification, thus broadening its range of applications. This review focuses on multifunctional hydrogels containing GA, aiming to inspire researchers in future biomaterial design. We first revealed the interaction mechanisms between GA molecules and between GA and polymers, analyzed the characteristics GA imparts to hydrogels and compared GA hydrogels with hydrogels containing catechol. Subsequently, in this paper, various methods of integrating GA into hydrogels and the applications of GA in biomedicine are discussed, finally assessing the current limitations and future development potential of GA. In summary, GA, a natural small molecule polyphenol with excellent functionality and diverse interaction modes, has great potential in the field of biomedical hydrogels.


Assuntos
Ácido Gálico , Pirogalol , Ácido Gálico/farmacologia , Ácido Gálico/química , Pirogalol/farmacologia , Hidrogéis/química , Polifenóis , Catecóis
13.
Int J Biol Macromol ; 262(Pt 2): 130086, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38360224

RESUMO

This study was designed to investigate the effect of polyphenolic structure on the interaction strength and process between polyphenols (gallic acid (GA), epigallocatechin gallate (EGCG) and tannic acid (TA)) and amylose (AM). The results of Fourier transform infrared spectroscopy, isothermal titration calorimetry, X-ray photoelectron spectroscopy and molecular dynamic simulation (MD) suggested that the interactions between the three polyphenols and AM were noncovalent, spontaneous, low-energy and driven by enthalpy, which would be enhanced with increasing amounts of pyrogallol groups in the polyphenols. The results of turbidity, particle size and appearance of the complex solution showed that the interaction process between polyphenols and AM could be divided into three steps and would be advanced by increasing the number of pyrogallol groups in the polyphenols. At the same time, MD was intuitively employed to exhibit the interaction process between amylose and polyphenols, and it revealed that the interaction induced the aggregation of amylose and that the agglomeration degree of amylose increased with increasing number of pyrogallol groups at polyphenols. Last, the SEM and TGA results showed that TA/AM complexes had the tightest structure and the highest thermal stability (TA/AM˃EGCG/AM˃GA/AM), which could be attributed to TA having five pyrogallol groups.


Assuntos
Amilose , Pirogalol , Pirogalol/química , Polifenóis/química , Ácido Gálico/química
14.
Int J Biol Macromol ; 263(Pt 1): 130159, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38368972

RESUMO

In this work, chitosan films loaded with gallic acid and different content of chitin nanofibers were prepared and subjected to different characterization techniques. The results showed that the inclusion of gallic acid to chitosan films caused moderate decrease in water vapor permeability (by 29 %) and increased tensile strength of films (by 169 %) in comparison to the neat chitosan films. Furthermore, it was found that the addition of chitin nanofibers up to 30 % into chitosan/gallic acid films additionally improved tensile strength (by 474 %) and reduced plasticity of films (by 171 %), when compared to the chitosan/gallic acid films. Increased concentration of chitin nanofibers in films reduced the overall water vapor permeability of films by 51 %. In addition, gallic acid and chitin nanofibers had synergic effect on high chitosan film's antioxidant and antifungal activity toward Botrytis cinerea (both above 95 %). Finally, chitosan/gallic acid/chitin nanofibers films reduced decay incidence of strawberries, increased total soluble solid content, and promoted high production of some polyphenols during cold storage, in comparison to the control chitosan films and uncoated strawberry samples. Hence, these results suggest that chitosan/gallic acid/chitin nanofibers can present eco-sustainable approach for preservation of strawberries, giving them additional nutritional value.


Assuntos
Quitosana , Nanofibras , Quitosana/farmacologia , Quitosana/química , Quitina/química , Ácido Gálico/química , Nanofibras/química , Vapor , Embalagem de Alimentos/métodos
15.
Int J Biol Macromol ; 263(Pt 2): 130331, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403209

RESUMO

This study aimed to investigate the multiscale structure, physicochemical properties, and in vitro digestibility of black rice starch (BRS) and gallic acid (GA) complexes prepared using varying ultrasound powers. The findings revealed that ultrasonic treatment disrupted BRS granules while enhancing the composite degree with GA. The starch granules enlarged and aggregated into complexes with uneven surfaces. Moreover, the crystallinity of the BRS-GA complexes increased to 22.73 % and formed V6-I-type complexes through non-covalent bonds. The increased short-range ordering of the complexes and nuclear magnetic resonance hydrogen (1H NMR) further indicated that the BRS and GA molecules interacted mainly through non-covalent bonds such as hydrogen bonds. Additionally, ultrasound reduced the viscoelasticity of the complexes while minimizing the mass loss of the complexes at the same temperature. In vitro digestion results demonstrated an increase in resistant starch content up to 37.60 % for the BRS-GA complexes. Therefore, ultrasound contributes to the formation of V-typed complexes of BRS and GA, which proves the feasibility of using ultrasound alone for the preparation of starch and polyphenol complexes while providing a basis for the multiscale structure and digestibility of polyphenol and starch complexes.


Assuntos
Oryza , Oryza/química , Ácido Gálico/química , Digestão , Amido/química , Polifenóis
16.
Food Chem ; 442: 138529, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38271912

RESUMO

HPLC-UV analysis was used to evaluate the enzymatic degradation characteristics of tyrosol acyl esters (TYr-Es) and alkyl gallates (A-GAs). Among various hydrolytic enzymes, TYr-Es can be hydrolyzed by pancrelipase, while A-GAs cannot be hydrolyzed by pancrelipase. Interestingly, carboxylesterase-1b (CES-1b), carboxylesterase-1c (CES-1c) and carboxylesterase-2 (CES-2) are able to hydrolyze TYr-Es and A-GAs, and thus to liberate tyrosol (TYr) and gallic acid (GA). By contrast, the degrees of hydrolysis (DHs) of TYr-Es and A-GAs by CES-1b and CES-1c were significantly higher than those by CES-2. Meanwhile, the DHs of TYr-Es were much higher than those of A-GAs. Especially, the DHs firstly increased and then decreased with the increasing alkyl chain length. Besides, DHs positively correlated with the unsaturation degree at the same chain length. Through regulating carbon length, unsaturation degree and the ester bond structure, controlled-release of phenolic compounds and fatty acids (or fatty alcohols) from phenolic esters will be easily achieved.


Assuntos
Ésteres , Ácido Gálico , Álcool Feniletílico/análogos & derivados , Hidrólise , Ácido Gálico/química , Ésteres/química , Pancrelipase , Cromatografia Líquida de Alta Pressão
17.
J Agric Food Chem ; 72(4): 1894-1901, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36748888

RESUMO

Supramolecular study of the interactions between the major wine anthocyanin, malvidin-3-O-glucoside (Mv3G) and different wine phenolic compounds (quercetin 3-O-ß-glucopyranoside (QG), caffeic acid, (-)-epicatechin, (+)-catechin, and gallic acid) has been performed at two different molar ratios (1:1 and 1:2) in acidic medium where flavylium cation predominates (pH ≤ 2). Color variations have been evaluated by differential colorimetry using CIELAB color space. These studies have been complemented with isothermal titration calorimetry assays and molecular dynamics simulations. The color of Mv3G flavylium cation is modified by the interaction with QG toward more bluish and intense colors. Interaction constants between the anthocyanin and the different phenolic compounds were obtained, ranging from 9.72 × 108 M-1 for QG to 1.50 × 102 M-1 for catechin. Hydrophobic interactions and H-bonds are the main driving forces in the pigment/copigment aggregation, except for the interactions where caffeic acid is involved, in which hydrophobic interactions acquire greater preponderance.


Assuntos
Antocianinas , Ácidos Cafeicos , Vinho , Antocianinas/química , Catequina/química , Cátions , Cor , Fenóis/química , Vinho/análise , Ácido Gálico/química
18.
Int J Biol Macromol ; 255: 128217, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992932

RESUMO

The significant threat of foodborne pathogens contamination has continuously promoted the development of efficient antimicrobial food packaging materials. Here, an antimicrobial film was prepared with gallic acid-grafted-chitosan (CS/GA) that obtained by a two-step ultrasound method. The resultant films exhibited good transparency, improved UV barrier performance, and enhanced mechanical strength. Specifically, with the grafting of 1.2 % GA, the UV blocking ability of CS/GA film at 400 nm was significantly increased by 19.7 % and the tensile strength was nearly two times higher than that of CS film. Moreover, the CS/GA films exhibited an inspiring photoactivated bactericidal ability under 400 nm UVA light irradiation that eradicated almost 99.9 % of Staphylococcus aureus (S. aureus) cells within 60 min. To gain more insights into the antibacterial mechanism, the treated S. aureus cells were further investigated by visualizing bacterial ultrastructure and analyzing membrane properties. The results pointed to the peptidoglycan layer as the primary action target when bacteria come into contact with CS/GA films. Afterward, the intracellular oxidative lesions, disrupted bacterial integrity, and disordered membrane functional properties collectively resulted in eventual cell death. The findings revealed the unique peptidoglycan targeting and membrane disruptive mechanisms of CS/GA films, confirming the application values in controlling foodborne pathogens.


Assuntos
Anti-Infecciosos , Quitosana , Staphylococcus aureus , Quitosana/farmacologia , Quitosana/química , Ácido Gálico/farmacologia , Ácido Gálico/química , Raios Ultravioleta , Peptidoglicano , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/química , Embalagem de Alimentos/métodos
19.
J Sci Food Agric ; 104(4): 1942-1952, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-37886811

RESUMO

BACKGROUND: Composite nanofiber films loaded with ε-polylysine (PL) and gallic acid (GA) were prepared using a zein/gelatin (ZG) electrospinning method to develop effective active packaging films for tuna preservation. The morphology, structure, thermal stability, hydrophobicity, antibacterial, and antioxidant properties of the films, and their application for tuna during a period of storage of 4 °C were investigated. RESULTS: PL reduced the average diameter of ZG fibers, whereas GA increased it. The PL/GA/ZG film possessed a well distributed fiber morphology with an average diameter of 810 ± 150 nm. Fourier-transform infrared spectroscopy and X-ray diffraction results showed the physical loading of PL and GA in ZG film with the main chemical bonds and crystal structure unchanged. The addition of both PL and GA reduced hydrophobicity of the ZG film while the PL/GA/ZG film was still hydrophobic. GA enhanced its thermal stability and contributed to its antioxidant activity. PL and GA synergetically enhanced the antibacterial activity of ZG film against Shewanella putrefaciens. PL combined with GA is more suitable for modifying ZG film than GA alone. The PL/GA/ZG film effectively inhibited total viable counts, total volatile base nitrogen, fat oxidation, and texture deterioration of tuna fillets at 4 °C storage, and could extend the shelf life by 3 days. CONCLUSIONS: The PL/GA/ZG nanofiber film demonstrated promising potential for application in the preservation of aquatic products as a new antibacterial and antioxidant food packaging. © 2023 Society of Chemical Industry.


Assuntos
Ácido Gálico , Zeína , Animais , Ácido Gálico/química , Antioxidantes/química , Zeína/química , Polilisina/farmacologia , Atum , Gelatina , Antibacterianos/farmacologia , Antibacterianos/química , Embalagem de Alimentos/métodos
20.
Int J Biol Macromol ; 257(Pt 2): 128743, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38100960

RESUMO

In this study, sesame (Sesamum indicum L.) meal protein and common vetch (Vicia sativa L.) starch were extracted and used to obtain biodegradable composite films at different pH values (7, 9, and 11). Films were plasticized with glycerol (2.5 %) and enriched with gallic acid (0.25 %). Increasing pH promoted mechanical properties of the films with the developed barrier and thermal characteristics. Gallic acid addition at pH 7 resulted in lower tensile strength and higher elongation by reducing intermolecular forces, and a shift of diffraction peaks through lower angles due to crystal lattice expansion, as compared to neutral films without gallic acid. On the other hand, gallic acid-enriched films at neutral pH exhibited superior antioxidant properties. The mild alkalinity with gallic acid provided the lowest water vapor permeability, high thermal stability, improved mechanical properties and light barrier property due to deprotonation and subsequent interactions with biopolymers. The FTIR spectrum confirmed intense interactions, such as crosslinking and covalent bonding, promoted by mild alkalinity. Therefore, sesame protein and common vetch starch-based composite film with gallic acid incorporation at pH 9 can be recommended to be used in biodegradable active food packaging applications.


Assuntos
Sesamum , Vicia sativa , Amido/química , Ácido Gálico/química , Resistência à Tração , Permeabilidade , Concentração de Íons de Hidrogênio , Embalagem de Alimentos/métodos
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