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1.
Molecules ; 28(3)2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36770908

RESUMEN

Food allergies are a serious food safety and public health issue. Soybean, dairy, aquatic, poultry, and nut products are common allergens inducing allergic reactions and adverse symptoms such as atopic dermatitis, allergic eczema, allergic asthma, and allergic rhinitis. Probiotics are assumed as an essential ingredient in maintaining intestinal microorganisms' composition. They have unique physiological roles and therapeutic effects in maintaining the mucosal barrier, immune function, and gastrointestinal tract, inhibiting the invasion of pathogenic bacteria, and preventing diarrhea and food allergies. Multiple pieces of evidence reveal a significant disruptive effect of probiotics on food allergy pathology and progression mechanisms. Thus, this review describes the allergenic proteins as an entry point and briefly describes the application of probiotics in allergenic foods. Then, the role of probiotics in preventing and curing allergic diseases by regulating human immunity through intestinal flora and intestinal barrier, modulating host immune active cells, and improving host amino acid metabolism are described in detail. The anti-allergic role of probiotics in the function and metabolism of the gastrointestinal tract has been comprehensively explored to furnish insights for relieving food allergy symptoms and preventing food allergy.


Asunto(s)
Dermatitis Atópica , Hipersensibilidad a los Alimentos , Probióticos , Humanos , Hipersensibilidad a los Alimentos/tratamiento farmacológico , Dermatitis Atópica/tratamiento farmacológico , Alérgenos/uso terapéutico , Probióticos/farmacología , Probióticos/uso terapéutico , Inmunidad , Inmunomodulación
2.
Glycoconj J ; 37(2): 165-174, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32026252

RESUMEN

The study of carbohydrates requires large amounts of glycans. N-Glycans can be synthesized but generating large quantities of N-glycans with diverse structures remains difficult. In this study, we aimed to obtain large amounts of glycans using an optimized procedure. Two types of reductive N-glycans were released from chicken egg albumin (ovalbumin) and soy protein using an ammonia catalysis method and labeled with benzenesulfonyl hydrazide (BSH). After preliminary separation by preparative HPLC, N-glycan-BSH components were de-labeled separately and reducing N-glycans were recovered. The de-labeled reducing N-glycans were derived with different labeling reagents and further separated and purified with two/multi-dimensional HPLC for various studies. We selected the bifunctional reagent 2-amino-N-(2-aminoethyl)-benzamide (AEAB) as a labeling reagent combined with C18 column for two-dimensional HPLC separation. A total of 21 and 8 N-glycan-AEAB conjugates were obtained from ovalbumin and soy protein, respectively. A reactive primary alkylamine of N-glycan-AEAB conjugates can be effectively immobilized on microarray surfaces, allowing for subsequent functional studies of glycans.


Asunto(s)
Polisacáridos/síntesis química , Amoníaco/química , Benzamidas/química , Bencenosulfonatos/química , Catálisis , Cromatografía Líquida de Alta Presión/métodos , Ovalbúmina/química , Proteínas de Soja/química
3.
Arch Microbiol ; 201(4): 451-458, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30293114

RESUMEN

In this study, the antimicrobial mechanism of cinnamaldehyde (CIN) against Gram-negative Escherichia coli ATCC 25922 (E. coli) based on membrane and gene regulation was investigated. Treatment with low concentration (0, 1/8, 1/4, 3/8 MIC) of CIN can effectively suppress the growth of E. coli by prolonging its lag phase and Raman spectroscopy showed obvious distinction of the E. coli after being treated with these concentration of CIN. The determination of relative conductivity indicated that CIN at relatively high concentration (0, 1, 2, 4 MIC) can increase the cell membrane permeability, causing the leakage of cellular content. Besides, the content of malondialdehyde (MDA) and the activity of total superoxide dismutase (SOD) of E. coli increased with increasing treatment concentration of CIN, implying that CIN can cause oxidative damage on E. coli cell membrane and induce the increase of total SOD activity to resist this oxidative harm. Moreover, quantitative real-time RT-PCR (qRT-PCR) analysis revealed the relationship between expression of antioxidant genes (SODa, SODb, SODc) and treatment CIN concentration, suggesting that SOD, especially SODc, played a significant role in resistance of E. coli to CIN. The underlying inactivation processing of CIN on E. coli was explored to support CIN as a potential and natural antimicrobial agent in food industry.


Asunto(s)
Acroleína/análogos & derivados , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Estrés Oxidativo , Acroleína/farmacología , Antioxidantes/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , Escherichia coli/enzimología , Escherichia coli/genética , Escherichia coli/metabolismo , Malondialdehído/metabolismo , Superóxido Dismutasa/metabolismo
4.
Biochim Biophys Acta Biomembr ; 1860(2): 481-490, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29138066

RESUMEN

In this work, modifications of cell membrane fluidity, fatty acid composition and fatty acid biosynthesis-associated genes of Escherichia coli ATCC 25922 (E. coli) and Staphylococcus aureus ATCC 6538 (S. aureus), during growth in the presence of naringenin (NAR), one of the natural antibacterial components in citrus plants, was investigated. Compared to E. coli, the growth of S. aureus was significantly inhibited by NAR in low concentrations. Combination of gas chromatography-mass spectrometry with fluorescence polarization analysis revealed that E. coli and S. aureus cells increased membrane fluidity by altering the composition of membrane fatty acids after exposure to NAR. For example, E. coli cells produced more unsaturated fatty acids (from 18.5% to 43.3%) at the expense of both cyclopropane and saturated fatty acids after growth in the concentrations of NAR from 0 to 2.20mM. For S. aureus grown with NAR at 0 to 1.47mM, the relative proportions of anteiso-branched chain fatty acids increased from 37.2% to 54.4%, whereas iso-branched and straight chain fatty acids decreased from 30.0% and 33.1% to 21.6% and 23.7%, respectively. Real time q-PCR analysis showed that NAR at higher concentrations induced a significant down-regulation of fatty acid biosynthesis-associated genes in the bacteria, with the exception of an increased expression of fabA gene. The minimum inhibitory concentration (MIC) of NAR against these two bacteria was determined, and both of bacteria underwent morphological changes after exposure to 1.0 and 2.0 MIC.


Asunto(s)
Membrana Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Ácidos Grasos/biosíntesis , Flavanonas/farmacología , Genes Bacterianos/genética , Staphylococcus aureus/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Relación Dosis-Respuesta a Droga , Escherichia coli/genética , Escherichia coli/metabolismo , Flavanonas/química , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Fluidez de la Membrana/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Estructura Molecular , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
5.
Biochim Biophys Acta ; 1858(8): 1791-800, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27155566

RESUMEN

Effects of growth temperature on cell membrane fatty acid composition, fluidity and lethal and sublethal injury by pulsed electric fields (PEF) in Staphylococcus aureus ATCC 43300 (S. aureus) in the stationary phase were investigated. Analysis of the membrane fatty acids by gas chromatography-mass spectrometry (GC-MS) revealed that branched chain fatty acids (iso C14:0, iso C15:0, anteiso C15:0 and anteiso C17:0) and straight chain fatty acids (C12:0, C14:0, C16:0, C17:0 and C18:0) were primary constituents in the membrane. The S. aureus changed its membrane fatty acid composition and its overall fluidity when exposed to different temperatures. The PEF lethal and sublethal effects were assessed, and results suggested that the degree of inactivation depended on the cell membrane structure, electric field strength and treatment time. The PEF inactivation kinetics including lethal and sublethal injury fractions were fitted with non-linear Weibull distribution, suggesting that inactivation of the first log cycle of S. aureus population was significantly affected by growth temperature, and the membrane of cells became more fluid, and easier to induce electroportion in low temperatures. Moreover, the morphology of S. aureus cells were investigated by electron microscopy, showing that various temperature-modified cells were distorted to differing extents and some even collapsed due to deep irreversible electroporation after PEF treatment.


Asunto(s)
Membrana Celular/química , Campos Electromagnéticos , Ácidos Grasos/análisis , Lípidos de la Membrana/análisis , Staphylococcus aureus/química , Temperatura , Electroporación , Cromatografía de Gases y Espectrometría de Masas , Fluidez de la Membrana , Microscopía Electrónica , Staphylococcus aureus/fisiología , Staphylococcus aureus/ultraestructura
6.
Biochim Biophys Acta Gen Subj ; 1861(1 Pt A): 3189-3198, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27531708

RESUMEN

BACKGROUND: Some antibacterial agents exert their antimicrobial action by targeting the cytoplasmic macromolecules, such as proteins or nucleic acids, to disturb the properties of macromolecules that may deeply influence their biological activities and functions. Cinnamaldehyde (CIN) is a natural antibacterial ingredient found in the bark and leaves of cinnamon trees. METHODS: The inhibitory mechanism of a typical enzyme, ß-galactosidase by CIN was investigated by UV-visible, fluorescence, 3-D spectroscopy, circular dichroism, atomic force microscopy and molecular modeling studies. RESULTS: CIN decreased the activity of ß-galactosidase by competitive inhibition through a multiphase kinetic process. 3-D spectroscopy and circular dichroism showed that the binding of CIN to ß-galactosidase resulted in changes in micro-environment of tryptophan and tyrosine residues, and conformation of ß-galactosidase. The molecular recognition was also analyzed through modeling which indicated that CIN was inserted into the active site pocket of ß-galactosidase and interacted with amino acid residues, such as Met502, Trp568, Phe601 and Trp999. Atomic force microscopy showed that a serious destabilization of the native conformation of ß-galactosidase occurred after binding with CIN, e.g., morphological changes and increased dimensions of the ß-galactosidase molecule. Moreover, it was found that the combinations of CIN, carvacrol and thymol exposure displayed synergistic effects on the inhibition of ß-galactosidase. GENERAL SIGNIFICANCE: This study exhibits a comprehensively understanding about the action mechanism of CIN that affects the conformation and activity of ß-galactosidase in biochemical processes and provides some new insights into the possible intracellular targeting behaviors of CIN at a molecular level.


Asunto(s)
Acroleína/análogos & derivados , Monoterpenos/farmacología , Timol/farmacología , beta-Galactosidasa/antagonistas & inhibidores , Acroleína/química , Acroleína/farmacología , Sitios de Unión , Dicroismo Circular , Análisis por Conglomerados , Cimenos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Concentración de Iones de Hidrógeno , Cinética , Microscopía de Fuerza Atómica , Simulación del Acoplamiento Molecular , Monoterpenos/química , Espectrometría de Fluorescencia , Timol/química , beta-Galactosidasa/metabolismo
7.
Anal Bioanal Chem ; 409(6): 1615-1625, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27900434

RESUMEN

Thymol (2-isopropyl-5-methylphenol) is a natural ingredient used as flavor or preservative agent in food products. The antibacterial mechanism of thymol against Gram-positive, Staphylococcus aureus was investigated in this work. A total of 15 membrane fatty acids were identified in S. aureus cells by gas chromatography-mass spectrometry. Exposure to thymol at low concentrations induced obvious alterations in membrane fatty acid composition, such as decreasing the proportion of branched 12-methyltetradecanoic acid and 14-methylhexadecanoic acid (from 22.4 and 17.3% to 7.9 and 10.3%, respectively). Membrane permeability assay and morphological image showed that thymol at higher concentrations disrupted S. aureus cell membrane integrity, which may decrease cell viability. Moreover, the interaction of thymol with genomic DNA was also investigated using multi-spectroscopic techniques, docking and atomic force microscopy. The results indicated that thymol bound to the minor groove of DNA with binding constant (K a) value of (1.22 ± 0.14) × 104 M-1, and this binding interaction induced a mild destabilization in the DNA secondary structure, and made DNA molecules to be aggregated. Graphical Abstract Thymol exerts its antibacterial effect throught destruction of bacterial cell membrane and binding directly to genomic DNA.


Asunto(s)
Antibacterianos/farmacología , Staphylococcus aureus/efectos de los fármacos , Timol/farmacología , ADN Bacteriano/química , ADN Bacteriano/metabolismo , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Viabilidad Microbiana/efectos de los fármacos , Microscopía de Fuerza Atómica/métodos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Conformación de Ácido Nucleico/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/citología , Staphylococcus aureus/metabolismo
8.
Mol Biol Rep ; 41(5): 3381-91, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24500342

RESUMEN

Allura red (AR) is a widely used colorant in food industry, but may have a potential security risk. In this study, the properties of interaction between AR and human serum albumin (HSA) in vitro were determined by fluorescence, UV-Vis absorption and circular dichroism (CD) spectroscopy combining with multivariate curve resolution-alternating least squares (MCR-ALS) chemometrics and molecular modeling approaches. An expanded UV-Vis data matrix was resolved by MCR-ALS method, and the concentration profiles and pure spectra for the three reaction components (AR, HSA, and AR-HSA complex) of the system were then successfully obtained to evaluate the progress interaction of AR with HSA. The calculated thermodynamic parameters indicated that hydrogen binding and hydrophobic interactions played major roles in the binding process, and the interaction induced a decrease in the protein surface hydrophobicity. The competitive experiments revealed that AR mainly located in Sudlow's site I of HSA, and this result was further supported by molecular modeling studies. Analysis of CD spectra found that the addition of AR induced the conformational changes of HSA. This study have provided new insight into the mechanism of interaction between AR and HSA.


Asunto(s)
Compuestos Azo/química , Colorantes de Alimentos/química , Albúmina Sérica/química , Compuestos Azo/metabolismo , Sitios de Unión , Colorantes de Alimentos/metabolismo , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Estructura Molecular , Unión Proteica , Conformación Proteica , Albúmina Sérica/metabolismo , Termodinámica
9.
Pestic Biochem Physiol ; 108: 66-73, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24485317

RESUMEN

Prometryn possesses much potential hazard to environment because of its chemical stability and biological toxicity. Here, the binding properties of prometryn with human serum albumin (HSA) and the protein structural changes were determined under simulative physiological conditions (pH 7.4) by multispectroscopic methods including fluorescence, UV-vis absorption, Fourier transform infrared (FT-IR) and circular dichroism (CD) spectroscopy, coupled with molecular modeling technique. The result of fluorescence titration suggested that the fluorescence quenching of HSA by prometryn was considered as a static quenching procedure. The negative enthalpy change (ΔH(○)) and positive entropy change (ΔS(○)) values indicated that the binding process was governed mainly by hydrophobic interactions and hydrogen bonds. The site marker displacement experiments suggested the location of prometryn binding to HSA was Sudlow's site I in subdomain IIA. Furthermore, molecular docking studies revealed prometryn can bind in the large hydrophobic activity of subdomain IIA. Analysis of UV-vis absorption, synchronous fluorescence, CD and FT-IR spectra demonstrated that the addition of prometryn resulted in rearrangement and conformational alteration of HSA with reduction in α-helix and increases in ß-sheet, ß-turn and random coil structures. This work provided reasonable model helping us further understand the transportation, distribution and toxicity effect of prometryn when it spreads into human blood serum.


Asunto(s)
Prometrina/química , Albúmina Sérica/química , Sitios de Unión , Dicroismo Circular , Herbicidas/química , Humanos , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Simulación del Acoplamiento Molecular , Unión Proteica , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Espectroscopía Infrarroja por Transformada de Fourier
10.
Int J Biol Macromol ; 257(Pt 1): 128509, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38052285

RESUMEN

Previous studies demonstrated that the non-thermal effects of pulsed electric fields can promote protein glycation below 40 °C, but it does not always enhance the emulsifying properties of proteins, such as in the bovine serum albumin/glucose model. Therefore, the aim of this study was to investigate the impact of non-thermal effects on the glucose glycation and emulsification properties of bovine serum albumin at 90 °C. The results of circular dichroism, surface hydrophobicity, and molecular dynamics simulations showed that the polarization effect increased the degree of glycation of bovine serum albumin-glucose conjugates from 12.82 % to 21.10 % by unfolding protein molecule, while the emulsifying stability index was increased from 79.17 to 100.73 compared with the control. Furthermore, the results of principal component analysis and Pearson correlation analysis indicated that the ionization effect and the free radicals generated by pulsed electric fields significantly (p < 0.05) inhibited browning and reduced free sulfhydryl content. This study demonstrated that pulsed electric fields combined with heating can prepare glycated proteins with good emulsifying properties in a short period of time and at temperatures lower than conventional heating while reducing energy consumption. This processing strategy has potential applications in improving the emulsifying performance of highly stable proteins.


Asunto(s)
Reacción de Maillard , Albúmina Sérica Bovina , Temperatura , Glucosa , Interacciones Hidrofóbicas e Hidrofílicas
11.
Ultrason Sonochem ; 107: 106931, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823084

RESUMEN

Thawing is the primary step in handling frozen aquatic products, which directly determines their end-product quality. This study firstly constructed a novel thawing method of ultrasound-assisted slightly basic electrolyzed water (UST), and its influences on the physicochemical and histological properties of shrimp, as well as the structural of myofibrillar proteins (MPs) in shrimp were evaluated. Results indicated that the UST treatment greatly reduced 48.9 % thawing time of frozen shrimp compared to traditional thawing approaches. Meanwhile, the UST effectively decreased the generation of malondialdehyde (MDA), total volatile basic nitrogen (TVB-N), and carbonyl compounds in the thawed shrimps. In addition, it significantly preserved the elasticity and integrity of muscle fiber. Notably, the UST reduced the damage of thawing to the spatial structures of MPs, thereby greatly keeping the stability of protein. All these favorable changes maintained the water holding capacity (WHC) and quality of shrimp. Therefore, the UST is a promising non-thermal thawing technology for aquatic products.


Asunto(s)
Congelación , Penaeidae , Agua , Animales , Agua/química , Penaeidae/química , Ondas Ultrasónicas , Electrólisis/métodos , Malondialdehído , Manipulación de Alimentos/métodos
12.
Foods ; 12(4)2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36832979

RESUMEN

The inhibitory activity of hesperetin on polyphenol oxidase (PPO) and their interaction characteristics were investigated using multiple spectroscopic methods and computational simulation. Hesperetin, a mixed inhibitor, reversibly inhibited PPO activity, and its half-maximum inhibitory concentration (IC50) values on monophenolase and diphenolase were 80.8 ± 1.4 µM and 776.0 ± 15.5 µM, respectively. Multivariate curve resolution-alternate least squares (MCR-ALS) analysis suggested PPO interacted with hesperetin and formed PPO-hesperetin complex. Hesperetin statically quenched PPO's endogenous fluorescence, and hydrophobic interactions mainly drove their binding. Hesperetin affected the polarity of the microenvironment around the Trp residues in PPO, but had no effect on that around Tyr residues. Circular dichroism (CD) results showed that hesperetin increased α-helix content and decreased ß-fold and random coil contents, thus tightening PPO's structure. Molecular docking showed that hesperetin entered the hydrophobic cavity of PPO, bound near the dinuclear copper active center, interacted with Val283, Phe264, His85, Asn260, Val248, and His263 via hydrophobic interactions, formed hydrogen bonds with Met280, His89, and His259 residues and also interacted with Phe292, His61, Phe90, Glu256, His244, Asn260, Phe264, and Gly281 via van der Waals forces. The molecular dynamics simulation results also demonstrated that the addition of hesperetin reduced the stability and hydrophobicity of PPO and increased PPO's structural denseness. Thus, the inhibition of hesperetin on PPO may be because hesperetin bound near the active center of PPO, interacted with the surrounding residues, occupied the binding site for substrate, and induced the changes in PPO's secondary structure, thus inhibiting the catalytic activity of PPO. This study may provide novel views for the inhibition of hesperetin on PPO and theoretical guidance for developing flavonoids as new and efficient PPO inhibitors.

13.
Food Res Int ; 170: 113000, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37316070

RESUMEN

This study aimed to explore the impacts of gallic acid (GA)/protocatechuic acid (PA) on the structural and functional characteristics of whey proteins (WP) through covalent binding. To this purpose, the covalent complexes of WP-PA and WP-GA at different concentration gradients were prepared by the alkaline method. SDS-PAGE indicated that PA/GA was cross-linked by covalent bonds. The decreased contents of free amino and sulfhydryl groups suggested that WP formed covalent bonds with PA/GA by amino and sulfhydryl groups, and the structure of WP became slightly looser after covalent modification by PA/GA. When the concentration of GA was added up to 10 mM, the structure of WP was slightly loosened with a reduction of α-helix content by 2.3% and an increase in random coil content by 3.0%. The emulsion stability index of WP increased by 14.9 min after interaction with GA. Moreover, the binding of WP and 2-10 mM PA/GA increased the denaturation temperature by 1.95 to 19.87 °C, indicating the improved thermal stability of the PA/GA-WP covalent complex. Additionally, the antioxidant capacity of WP was increased with increasing GA/PA concentration. This work may offer worthful information for enhancing the functional properties of WP and the application of the PA/GA-WP covalent complexes in food emulsifiers.


Asunto(s)
Ácido Gálico , Hidroxibenzoatos , Proteína de Suero de Leche , Emulsiones
14.
Foods ; 12(17)2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37685122

RESUMEN

In this study, porous starch was modified using pulsed electric field (PEF) pretreatment and alcoholic-alkaline treatment to prepare porous granular cold-water-soluble starch (P-GCWSS). The soluble porous starch has high adsorption capability and high cold water solubility, allowing effective encapsulation of zeaxanthin and improving zeaxanthin's water solubility, stability, and bioavailability. The physical and chemical properties of GCWSS and complex were investigated using scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. The results showed that the cold water solubility of the pulsed electric field-treated porous granular cold-water-soluble starch (PEF-P-GCWSS) increased by 12.81% compared to granular cold-water-soluble starch (GCWSS). The pulsed electric field treatment also increased the oil absorption of PEF-P-GCWSS was improved by 15.32% compared to porous granular cold-water-soluble starch (P-GCWSS). PEF-P-GCWSS was effective in encapsulating zeaxanthin, which provided a good protection for zeaxanthin. The zeaxanthin-saturated solubility in water of PPG-Z was increased by 56.72% compared with free zeaxanthin. The zeaxanthin embedded in PEF-P-GCWSS was able to be released slowly during gastric digestion and released rapidly during intestinal digestion.

15.
Foods ; 12(17)2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37685209

RESUMEN

The aim of this research was to investigate the antimicrobial characteristics and mechanism of hesperetin against Alicyclobacillus acidoterrestris vegetative cells. The results presented show that hesperetin had effective antimicrobial activity on Alicyclobacillus acidoterrestris vegetative cells, minimum inhibition concentration (MIC) of 0.0625 g/L, and minimum bacterial concentration (MBC) greater than 2 g/L. Moreover, treatment of hesperetin caused significant damage to cell integrity, preventing the growth of Alicyclobacillus acidoterrestris vegetative cells, enhancing the leakage of nucleic acid and proteins, and destroying the vegetative cell morphology. To further investigate the mechanism, transcriptomic analysis was carried out, and 3056 differentially expressed genes (DEGs) were detected. Gene ontology (GO) enrichment analysis revealed that hesperetin inhibits Alicyclobacillus acidoterrestris by affecting the intracellular nitrogen metabolism and amino acid metabolism. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis explained that hesperetin was also able to prevent the growth of Alicyclobacillus acidoterrestris by affecting the processes of nutrient transport, energy metabolism, and flagella motility. These results provide new insights into the antimicrobial effects and mechanism of hesperetin against Alicyclobacillus acidoterrestris, which provides a new method for inactive Alicyclobacillus acidoterrestris in the juice industry.

16.
Int J Biol Macromol ; 248: 125871, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37473896

RESUMEN

Microcapsules could improve the protection of probiotics in the lyophilization and gastrointestinal digestion process. The purpose of this study was to prepare Lactiplantibacillus plantarum DMDL 9010 (LP9010) microcapsules by cross-linking chitosan with genipin and to determine the encapsulation efficiency, morphological characterization, storage stability and the application of the microcapsules in fermentation. The results showed that the LP9010 microcapsules embedded in 1.00 wt% genipin cross-linked chitosan were in a uniform spherical shape with a smooth surface and satisfying agglomeration. The LP9010 microcapsules demonstrated the reasonable thermal stability and persistence of biological activity in the range of -20 °C to 25 °C. Additionally, yogurt obtained from the ST + LB + ELP9010 strain formulation with the addition of microencapsulated LP9010 had smaller particles, better taste, and better stability compared with the yogurt obtained from other strain formulations. As detected by GC-MS, the yogurt formulated with ST + LB + ELP9010 as a strain retained more flavor substances and the content of flavor substances was greater than that of the yogurt obtained from other strain formulations. Therefore, genipin cross-link chitosan could be a suitable microencapsulated material for producing yogurt fermentation strains.


Asunto(s)
Quitosano , Yogur , Cápsulas , Fermentación
17.
Int J Biol Macromol ; 231: 123085, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36592854

RESUMEN

The influence of pulsed electric field (PEF) combined with octenyl succinic anhydride (OSA) on the freeze-thaw stability of corn starch gel was investigated. After five freeze-thaw cycles, the syneresis value of OSA starch treated with PEF-assisted esterification for 15 min was lower by 29.5 %, while that of OSA starch without PEF treatment was lower by 10.17 %, compared to that of native starch. Low-field nuclear magnetic resonance data showed that the introduction of OSA groups greatly increased the water-holding capacity of starch. Results from differential scanning calorimetry (DSC) and X-ray diffraction (XRD) showed that the PEF-assisted esterification markedly hindered the re-formation of the helical structure of starch during freeze-thaw cycles. Moreover, PEF-assisted esterification improved the viscoelastic properties of the starch gel. It is found that the freeze-thaw stability of the PEF-modified starch depends not only on the degree of substitution but also on the starch molecular fine structure. PEF-assisted OSA starch with a high degree of substitution, a low content of amylose, and a high content of short amylopectin chains were found to have high freeze-thaw stability. This study shows that PEF-assisted esterification is a promising technique that should be used for preserving the quality of frozen foods.


Asunto(s)
Almidón , Zea mays , Almidón/química , Estructura Molecular , Esterificación
18.
Food Chem ; 424: 136386, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37236083

RESUMEN

In this study, soy protein isolate (SPI) was modified by a pulsed electric field (PEF) combined with pH shifting treatment (10 kV/cm, pH 11) to prepare SPI nanoparticles (PSPI11) for efficient loading of lutein. The results showed that when the mass ratio of SPI to lutein was 25:1, the encapsulation efficiency of lutein in PSPI11 increased from 54% to 77%, and the loading capacity increased by 41% compared to the original SPI. The formed SPI-lutein composite nanoparticles (PSPI11-LUTNPs) had smaller, more homogeneous sizes and larger negative charges than SPI7-LUTNPs. The combined treatment favored the unfolding of the SPI structure and could expose its interior hydrophobic groups to bind with lutein. Nanocomplexation with SPIs significantly improved the solubility and stability of lutein, with PSPI11 showing the greatest improvement. As a result, PEF combined with pH shifting pretreatment is an effective method for developing SPI nanoparticles loaded and protected with lutein.


Asunto(s)
Nanopartículas , Proteínas de Soja , Proteínas de Soja/química , Luteína , Nanopartículas/química , Interacciones Hidrofóbicas e Hidrofílicas , Concentración de Iones de Hidrógeno
20.
Front Nutr ; 9: 1064812, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36570165

RESUMEN

The aim of this work was to investigate the effects of dielectric barrier discharge-air cold plasma (DBD-ACP, 15-35 kV, 2-12 min) on the quality of foxtail millets. The L and b* values were evaluated by a digital colorimeter representing that the color of millets was significantly changed at 25 kV for 4-12 min or at 35 kV for 2-12 min. The results were consistent with the change of total yellow pigment in millets, indicating that DBD-ACP damaged the carotenoids if the treatment condition was too high. The activity of lipoxygenase and lipase, involving the oxidation and hydrolysis of lipids of millet, decreased significantly induced by DBD-ACP. For example, the lipoxygenase and lipase activity of Mizhi millet was decreased from 44.0 to 18.7 U g-1min-1, 56.0-15.1 U/(mg pro) (p<0.05) after being exposed to 25 kV for 2-12 min, respectively. Changes of color, lipoxygenase and lipase activity, and malondialdehyde content of millets were determined during accelerated storage (40 ± 2°C and 75% Relative Humidity) for 15 days after being treated by DBD-ACP under 15 and 25 kV for 4 min. Results showed that millets treated by DBD-ACP at 15 kV kept a better color with lower malondialdehyde content, and lower lipoxygenase and lipase activity compared to control. This work implied that DBD-ACP is an underlying approach for the storage of foxtail millets.

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