Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Braz J Otorhinolaryngol ; 90(2): 101384, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38228050

RESUMEN

OBJECTIVE: Laryngeal cancer, characterized by high recurrence rates and a lack of effective biomarkers, has been associated with cuproptosis, a regulated cell death process linked to cancer progression. In this study, we aimed to explore the roles of cuproptosis-related genes in laryngeal cancer and their potential as prognostic markers and therapeutic targets. METHODS: We collected comprehensive data from The Cancer Genome Atlas and Gene Expression Omnibus databases, including gene expression profiles and clinical data of laryngeal cancer patients. Using clustering and gene analysis, we identified cuproptosis-related genes with prognostic significance. A risk model was constructed based on these genes, categorizing patients into high- and low-risk groups for outcome comparison. Univariate and multivariate analyses were conducted to identify independent prognostic factors, which were then incorporated into a nomogram. Gene Set Enrichment Analysis was employed to explore pathways distinguishing high- and low-risk groups. RESULTS: Our risk model, based on four genes, including transmembrane 2, dishevelled binding antagonist of ß-catenin 1, stathmin 2, and G protein-coupled receptor 173, revealed significant differences in patient outcomes between high- and low-risk groups. Independent prognostic factors were identified and integrated into a nomogram, providing a valuable tool for prognostic prediction. Gene Set Enrichment Analysis uncovered up-regulated pathways specifically associated with high-risk patient samples. CONCLUSION: This study highlights the potential of cuproptosis-related genes as valuable prognostic markers and promising therapeutic targets in the context of laryngeal cancer. This research sheds light on new avenues for understanding and managing this challenging disease. LEVEL OF EVIDENCE: Level 4.


Asunto(s)
Neoplasias Laríngeas , Humanos , Neoplasias Laríngeas/genética , Pronóstico , Análisis Multivariante , Apoptosis
2.
Foods ; 12(16)2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37628005

RESUMEN

This study investigated changes in the microbial compositions of crayfish tails during storage at 4 °C (for 0-12 days) as measured using high-throughput sequencing (HTS). The specific spoilage organisms (SSOs) in the crayfish tails were isolated using culture-dependent cultivation methods, and they were identified by 16S rRNA and characterized for their enzymatic spoilage potentials (e.g., protease, lipase, phospholipase, and amylase). The spoilage abilities of the selected strains in the crayfish tails were assessed by inoculating them into real food. Moreover, the microbial growth and the volatile basic nitrogen (TVB-N) changes were monitored during the storage period. The results from the HTS showed that the dominant genus of shrimp tails evolved from Streptococcus (D0) to Pseudomonas (D4) and, finally, to Paenisporosarcina (D12) during storage. Seven bacterial species (Acinetobacter lwoffii, Aeromonas veronii, Kurthia gibsonii, Pseudomonas sp., Exiguobacterium aurantiacum, Lelliottia amnigena, and Citrobacter freundii) were screened from the spoiled shrimp tails by the culture-dependent method, among which Aeromonas veronii had the strongest spoilage ability.

3.
Ultrason Sonochem ; 98: 106517, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37454538

RESUMEN

In this study, a decontamination technology combining ultrasound (US) and plasma-activated water (PAW) was developed to better preserve crayfish. First, the decontamination efficacy of US, PAW and their combinations (UP) on crayfish was quantified after 0, 20, 40, or 60 min of treatments. The total viable count (TVC) was reduced by 0.27-0.77 Log CFU/g after individual US or PAW treatments, while a TVC reduction of 1.17 Log CFU/g was achieved after 40 min of UP treatment. Besides, the changes in psychrotrophic bacteria, lactic acid bacteria, yeasts and molds followed a similar trend to TVC. UP treatments normally resulted in more significant reductions in the natural microbiota of crayfish than US or PAW treatments. Furthermore, the microbial quality, physicochemical properties and sensory properties of crayfish after different treatments were assessed during storage at 4 °C for 12 days. According to TVC and total volatile basic nitrogen (TVB-N) values, the control group became unacceptable from 4 days, US or PAW groups became unacceptable from 6 days, while UP group extended the storage time to 8-10 days. During storage, thiobarbituric acid reactive substances (TBARS) values of all the groups were maintained below 0.5 mg/kg, among which the control group exhibited the highest value (0.39 mg/kg). Moreover, UP treatment effectively retarded the deterioration in color and texture properties of crayfish. Fourier transform infrared (FTIR) spectroscopy analysis indicated that UP treatment decreased the α-helix contents and increased the ß-sheet contents of crayfish proteins, while the structural changes were not evident at the end of storage. Low-field nuclear magnetic resonance (LF-NMR) analysis revealed that UP treatment reduced the water migration and enhanced the stability of bond water in crayfish. In addition, E-nose analysis revealed the protection of UP treatment on the sensory properties of crayfish during storage. This study demonstrated that the combinations of US and PAW treatments effectively accelerated the decontamination of crayfish and contributed to better storage quality.


Asunto(s)
Astacoidea , Agua , Animales , Viabilidad Microbiana , Recuento de Colonia Microbiana , Alimentos Marinos
4.
Ultrason Sonochem ; 92: 106259, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36502681

RESUMEN

To improve the quality of cooked and frozen crayfish after repeated freeze-thaw cycles, the effects of alginate oligosaccharide (1 %, w/v) with ultrasound-assisted (40 W, 3 min) soaking (AUS) on the physicochemical properties were investigated. The AUS samples improved water-holding capacity with 19.47 % higher than the untreated samples. Low-field nuclear magnetic resonance confirmed that mobile water (T22) in the samples after 5 times of freeze-thaw cycles was reduced by 13.02 % and 29.34 % with AUS and without treatment, correspondingly; and with AUS and without treatment, average size of the ice crystals was around 90.26 µm2 and 113.73 µm2, and average diameter of the ice crystals was 5.83 µm and 8.14 µm, respectively; furthermore, it enhanced the solubility and zeta potential, lowered the surface hydrophobicity, reduced the particle size, and maintained the secondary and tertiary structures of myofibrillar protein (MP) after repeated freeze-thawing. Gel electrophoresis revealed that the AUS treatment mitigated the denaturation of MPs. Scanning electron microscopy revealed that the AUS treatment preserved the structure of the tissue. These findings demonstrated that the AUS treatment could enhance the water retention and physicochemical properties of protein within aquatic meat products during temperature fluctuations..


Asunto(s)
Astacoidea , Hielo , Animales , Congelación , Proteínas , Agua/química , Oligosacáridos
5.
RSC Adv ; 12(39): 25744-25752, 2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-36199343

RESUMEN

Clostridium perfringens is an important foodborne pathogen, which has caused serious public health problems worldwide. So, there is an urgent need for rapid and ultrasensitive detection of C. perfringens. In this paper, a dual-mode sensing platform using the synergy between fluorescent and electrochemical signals for Clostridium perfringens detection was proposed. An electrochemical aptasensor was constructed by a dual-amplification technology based on a DNA walker and hybridization chain reaction (HCR). When the C. perfringens genomic DNA was present, it specifically bonded with FAM-labeled aptamer which triggered the DNA walker on hairpin DNA (hDNA) tracks to start the synthesis of double-stranded DNA. HCR occurred subsequently and produced long-chain DNA to absorb more methylene blue (MB). In this cycle, the fluorescent signals of released FAM-labeled aptamer could also be detected. The synergistic effects of MB and FAM significantly improved the sensitivity and accuracy of the dual-mode sensor. As a result, the biosensor displayed an excellent analytical performance for C. perfringens at a concentration of 1 to 108 CFU g-1. A minimum concentration of 1 CFU g-1 and good accuracy were detected in real samples. The proposed ultrasensitive detection method for detecting C. perfringens in food showed great potential in controlling foodborne diseases.

6.
Food Chem ; 395: 133615, 2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-35809551

RESUMEN

The effects of combined application of ultra-high pressure (300 Mpa, 900 s) and carnosine on the inhibition of fishy off-odor from snakehead meat were investigated. Results showed that the combination effectively inhibited the formation of fishy volatile organic compounds (VOCs) and trimethylamine (TMA-N). Further studies demonstrated that the reduction of VOCs was mainly due to the inhibition of lipids oxidation based on the antioxidant activity of carnosine and the inactivation of lipoxygenase by UHP. Moreover, the reduction of TMA-N was mainly attributed to the ability of UHP processing to reduce bacterial load, which also extended the shelf-life of snakehead fillets by âˆ¼ 6 days and retarded the production of TVB-N. Additionally, the combined application allowed a better retention of pH, color, and textural quality of the fillets compared with the control. Therefore, the current combination is a promising technique in fishy off-odor removing and better preservation of snakehead meat.


Asunto(s)
Carnosina , Odorantes , Conservación de Alimentos/métodos , Carne , Odorantes/análisis
7.
Food Chem ; 382: 132354, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35152010

RESUMEN

The properties, structure and water holding capacity of myosin were analyzed after incubated with myoglobin (Mb) hemin prosthetic group. The results revealed moderate oxidation of hemin prosthetic group could improve the solubility of myosin. Besides, it could stretch the protein structure and cross-link the molecules to form the soluble polymer. Hence, moderate oxidation could improve the gel properties and the gel network structure. However, excessive oxidation would greatly reduce the physical and chemical properties of myosin, which was not conducive to the gel formation and would lead to a decrease in water retention. Moreover, fluorescence spectroscopy and cyclic voltammetry (CV) proved hemin prosthetic group had a high affinity for myosin. The interaction mechanism was further studied by molecular docking and molecular dynamics (MD) simulations. This study provides some fundamental prospects to be applied in the functional regulation of meat protein.


Asunto(s)
Hemina , Mioglobina , Hemina/química , Calor , Simulación del Acoplamiento Molecular , Mioglobina/química , Miosinas/química
8.
Food Chem ; 374: 131624, 2022 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-34838399

RESUMEN

An efficient antibacterial nanoemulsion was prepared using zein and NaCas to encapsulate ginger essential oil (GEO). Physical, optical, and mechanical properties as well as the antibacterial activities of GEO nanoemulsion were investigated. At 1:1 mass ratio of zein/NaCas, the GEO nanoemulsion possessed the highest solubility, entrapment efficiency and stability. The GEO/zein/NaCas complex was confirmed by ultraviolet and fluorescence spectroscopy. The addition of GEO led to more amorphous structure formation and the secondary structure changes of zein/NaCas improved the solubility and stability of GEO. GEO nanoemulsion inactivated two common foodborne bacteria, namely, Staphylococcus aureus and Pseudomonas aeruginosa, by destroying the cell membrane. Meanwhile, the GEO nanoemulsion exhibited better preservation effects on chilled chicken breasts than non-emulsified GEO and could effectively prolong the shelf life of chicken breasts for 6 days. This research provides a green and low-cost method for preparing GEO nanoemulsion to control the risk of foodborne pathogens.


Asunto(s)
Antiinfecciosos , Aceites Volátiles , Zeína , Zingiber officinale , Animales , Antibacterianos , Pollos
9.
Front Cardiovasc Med ; 9: 1055897, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36712266

RESUMEN

Background: Pulmonary arterial hypertension (PAH) is a fatal disease characterized by pulmonary vascular remodeling and increased pulmonary artery pressure, leading to impaired lung oxygenation, right heart failure, and even death. Although great advances have been made in PAH-targeted medications for pediatric patients, the efficacy and safety of these treatments are controversial. Methods: We retrieved relevant articles from electronic databases including PubMed, EMBASE, Web of Science, and Cochrane Library until 12 April 2022. To compare the effectiveness and safety of endothelin receptor antagonists (ERAs), phosphodiesterase type 5 Inhibitors (PDE-5i), and prostaglandins (ProA) in the treatment of pediatric PAH, we investigated six hemodynamic parameters, four respiratory parameters, intensive care unit (ICU) stay duration, length of hospital stay, and two safety outcomes. Results: A total of 27 randomized controlled trials (RCTs) were included in the meta-analysis with 1,574 pediatric participants. The duration of mechanical ventilation was shorter for patients using bosentan, sildenafil, and ProsA, compared with that for patients using the placebo. Bosentan helped to shorten more time for mechanical ventilation than ProsA did, while ProsA was more effective than sildenafil in this respect. As for the length of stay in the ICU, patients administered by ProsA or sildenafil needed shorter ICU stay, compared to those using the placebo, while ProsA was more effective for shortening ICU stay time. In light of safety outcomes, there was a statistically significant difference between the sildenafil and the placebo group. Sildenafil surpassed ProsA in reducing the incidence of pulmonary hypertension (PH) crisis. Conclusions: ERAs were more effective than ProsA in shortening the duration of mechanical ventilation, while ProsA were better for shortening the duration of mechanical ventilation and ICU stay than PDE-5i. PDE-5i were found to generate more benefits in decreasing the occurrence of PH crisis, though further investigation is warranted. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=351505.

10.
Front Endocrinol (Lausanne) ; 12: 731273, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34489872

RESUMEN

Vascular aging is characterized by alterations in the constitutive properties and biological functions of the blood vessel wall. Endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) are indispensability elements in the inner layer and the medial layer of the blood vessel wall, respectively. Dipeptidyl peptidase-4 (DPP4) inhibitors, as a hypoglycemic agent, play a protective role in reversing vascular aging regardless of their effects in meliorating glycemic control in humans and animal models of type 2 diabetes mellitus (T2DM) through complex cellular mechanisms, including improving EC dysfunction, promoting EC proliferation and migration, alleviating EC senescence, obstructing EC apoptosis, suppressing the proliferation and migration of VSMCs, increasing circulating endothelial progenitor cell (EPC) levels, and preventing the infiltration of mononuclear macrophages. All of these showed that DPP4 inhibitors may exert a positive effect against vascular aging, thereby preventing vascular aging-related diseases. In the current review, we will summarize the cellular mechanism of DPP4 inhibitors regulating vascular aging; moreover, we also intend to compile the roles and the promising therapeutic application of DPP4 inhibitors in vascular aging-related diseases.


Asunto(s)
Envejecimiento/patología , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Enfermedades Vasculares/tratamiento farmacológico , Enfermedades Vasculares/etiología , Envejecimiento/efectos de los fármacos , Animales , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/patología , Diabetes Mellitus Tipo 2/fisiopatología , Angiopatías Diabéticas/etiología , Angiopatías Diabéticas/patología , Angiopatías Diabéticas/fisiopatología , Angiopatías Diabéticas/prevención & control , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Células Endoteliales/efectos de los fármacos , Células Endoteliales/patología , Células Endoteliales/fisiología , Humanos , Transducción de Señal/efectos de los fármacos
11.
World J Microbiol Biotechnol ; 36(2): 24, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31965331

RESUMEN

The study evaluated the antibacterial activity of chlorogenic acid (CA) against Salmonella Enteritidis S1, a foodborne pathogen in chilled fresh chicken. Its minimum inhibitory concentration for S. Enteritidis S1 was 2 mM. 1 MIC CA treatment reduced the viable count of S. Enteritidis S1 by 3 log cfu/g in chilled fresh chicken. Scanning electron microscopy examination indicated that CA induced the cell envelope damage of S. Enteritidis S1. Following this, 1-N-Phenylnaphthylamine assay and LPS content analysis indicated that CA induced the permeability of outer membrane (OM). Confocal laser scanning microscopy examination further demonstrated that CA acted on the inner membrane (IM). To support this, the release of intracellular protein and ATP after CA treatment was also observed. CA also suppressed the activities of malate dehydrogenase and succinate dehydrogenase, two main metabolic enzymes in TCA cycle and electron transport chain. Thus, damage of intracelluar and outer membranes as well as disruption of cell metabolism resulted in cell death eventually. The finding suggested that CA has the potential to be developed as a preservative to control S. Enteritidis associated foodborne diseases.


Asunto(s)
Antibacterianos/farmacología , Ácido Clorogénico/farmacología , Salmonella enteritidis/efectos de los fármacos , Animales , Proteínas Bacterianas/antagonistas & inhibidores , Membrana Celular/efectos de los fármacos , Pollos/microbiología , Recuento de Colonia Microbiana , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Malato Deshidrogenasa/antagonistas & inhibidores , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Microscopía Electrónica de Rastreo , Salmonella enteritidis/enzimología , Salmonella enteritidis/crecimiento & desarrollo , Succinato Deshidrogenasa/antagonistas & inhibidores
12.
Food Chem ; 314: 126173, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31954942

RESUMEN

The detection of phospholipids oxidation is important for meat control and disease prevention. In this paper, a photoelectrochemical sensor based on printable mesoscopic chip (PMC) for fast and real-time monitoring phospholipids oxidation was designed and fabricated. TiO2, ZrO2 and carbon films of PMC were screen-printed onto the FTO glass layer by layer. The PMC and the feasibility for determination of phospholipids oxidation were investigated by scanning electron microscope (SEM), UV-vis spectroscopy, cyclic voltammograms (CVs) and electrochemical impedance spectroscopy (EIS), etc. The short circuit current (Jsc) was used as a signal current, which would decrease if phospholipids in PMC were undergoing oxidation for the change of electrical properties. Compared with other methods, phospholipids in PMC did not require pretreatment, and the process was nondestructive and real-time. Meanwhile, this method showed high sensitivity and good selectivity. The fabricating process of PMC is simple, and the costs are low, relatively.


Asunto(s)
Espectroscopía Dieléctrica/instrumentación , Análisis de los Alimentos/instrumentación , Fosfolípidos/análisis , Carbono/química , Espectroscopía Dieléctrica/métodos , Diseño de Equipo , Análisis de los Alimentos/métodos , Lecitinas/análisis , Lecitinas/química , Microscopía Electrónica de Rastreo , Oxidación-Reducción , Fosfolípidos/química , Sensibilidad y Especificidad , Glycine max/química , Titanio/química
13.
Food Microbiol ; 86: 103344, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31703877

RESUMEN

This study aimed to evaluate the inhibitory activity of phenyllactic acid (PLA) against the biofilm formation of Enterococcus faecalis and to explore its potential molecular mechanism. The MIC value of PLA that inhibited the growth of E. faecalis R612-Z1 in BHI broth was 5 mg/mL. PLAs at subinhibitory concentrations of 1.25 and 2.50 mg/mL were found to inhibit biofilm formation by a crystal violet staining assay. The cell swimming and swarming motilities of E. faecalis were reduced in the presence of PLA. An apparent decrease in the thickness of PLA-treated biofilms was observed through confocal laser scanning microscopy analysis. The exopolysaccharide production in E. faecalis biofilms was inhibited by EPS quantification assay and scanning electron microscopy (SEM). qRT-PCR analyses showed that PLA down-regulated the transcription of Ebp pili genes (ebpABC) and Epa polysaccharide genes (epaABE). PLA inhibited the biofilm formation by interfering with cell mobility and EPS production of E. faecalis. In addition, PLA at concentrations of 10.0 mg/mL can effectively control the bacterial cells in a three-day-old mature biofilm of E. faecalis grown on 24-well flat-bottom polystyrene plates and stainless-steel surfaces. Thus, PLA is potentially an effective agent to control E. faecalis biofilms.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Enterococcus faecalis/efectos de los fármacos , Lactatos/farmacología , Polisacáridos Bacterianos/biosíntesis , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Enterococcus faecalis/crecimiento & desarrollo , Enterococcus faecalis/metabolismo , Pruebas de Sensibilidad Microbiana
14.
Foodborne Pathog Dis ; 16(12): 823-830, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31483172

RESUMEN

Chlorogenic acid (CA), an ester of caffeic acid, is a major phenolic compound in herbs. The antimicrobial activity of CA against Pseudomonas aeruginosa P1, a foodborne pathogen, was investigated in this study. To understand how CA injured target cells, the influence of CA on cell morphology was assessed. A sunken cell surface and detachment of outer membrane components in P. aeruginosa P1 were observed after being treated by CA. Following this, the intracellular membrane permeability and the content of lipopolysaccharide (LPS), a main component of outer membrane, were determined. The release of intracellular protein and ATP from P. aeruginosa P1 indicated that CA increased intracellular membrane permeability and resulted in the leakage of intracellular materials. The uptake of propidium iodide, a compromised cell membrane nucleic acid stain, further demonstrated that CA acted on the intracellular membrane. CA resulted in the decrease of LPS contents of P. aeruginosa P1, which supported the detachment of outer membrane. CA also downregulated the expression of major genes in LPS biosynthesis, suggesting that CA may inhibit intracellular metabolism of P. aeruginosa P1 cells. Thus, CA increased the intracellular membrane permeability, induced the exfoliation of outer membrane, and disturbed the intracellular metabolism. Damage of intracellular and outer membranes as well as disruption of cell metabolism resulted in cell death eventually. The finding suggested that CA has the potential to be developed as a preservative to control P. aeruginosa-associated foodborne diseases.


Asunto(s)
Antibacterianos/farmacología , Ácido Clorogénico/farmacología , Microbiología de Alimentos , Pseudomonas aeruginosa/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Conservantes de Alimentos , Humanos , Pruebas de Sensibilidad Microbiana
15.
Asian-Australas J Anim Sci ; 30(1): 94-99, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27189635

RESUMEN

OBJECTIVE: The aim of this study was to investigate the expression of heat shock protein (HSP) 90, 70, and 60 in chicken muscles and their possible relationship with quality traits of meat. METHODS: The breast muscles from one hundred broiler chickens were analyzed for drip loss and other quality parameters, and the levels of heat shock protein (HSP) 90, 70, and 60 were determined by immunoblots. RESULTS: Based on the data, chicken breast muscles were segregated into low (drip loss≤5%), intermediate (5%0.05). CONCLUSION: Results of this study suggests that higher levels of HSP90 and HSP60 may be advantageous for maintenance of cell function and reduction of water loss, and they could act as potential indicator for better water holding capacity of meat.

16.
J Poult Sci ; 53(1): 93-101, 2016 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-32908370

RESUMEN

This study aimed to characterize and optimize the tenderization condition of duck breast meat by adenosine 5'-monophosphate (AMP), with the aid of response surface methodology (RSM). The results showed that the optimal conditions for the tenderization of duck breast meat were at the NaCl concentration of 3.99 g/100 g, AMP concentration of 13.83 mmol/L, temperature of 15.32°C, and marinating time of 8 h. Compared with control duck breast meat, AMP combined with NaCl treatment demonstrated significant effects on improvement of meat tenderness and decrease of cooking loss. Such effects might be ascribed to the combination of a series of biochemical reactions, e.g. increase of muscle pH, dissociation of actomyosin and inhibition of meat shrinkage. Therefore, the mixture of AMP and NaCl could be regarded as an effective tenderization agent for duck breast meat.

17.
Anim Sci J ; 87(3): 439-48, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26212625

RESUMEN

Based on single factor experiments, NaCl concentration, adenosine 5'-monophosphate (AMP) concentration and temperature were selected as independent variables for a three-level Box-Behnken experimental design, and the shear force and cooking loss were response values for regression analysis. According to the statistical models, it showed that all independent variables had significant effects on shear force and cooking loss, and optimal values were at the NaCl concentration of 4.15%, AMP concentration of 22.27 mmol/L and temperature of 16.70°C, which was determined with three-dimensional response surface diagrams and contour plots. Under this condition, the observed shear force and cooking loss were 0.625 kg and 8.07%, respectively, exhibiting a good agreement with their predicted values, showing the good applicability and feasibility of response surface methodology (RSM) for improving pork tenderness. Compared with control pig muscles, AMP combined with NaCl treatment demonstrated significant effects on improvement of meat tenderness and reduction of cooking loss. Therefore, AMP could be regarded as an effective tenderization agent for pork.


Asunto(s)
Adenosina Monofosfato , Manipulación de Alimentos/métodos , Calidad de los Alimentos , Carne , Músculo Esquelético , Papaína , Sodio en la Dieta , Adenosina Monofosfato/análisis , Animales , Culinaria , Combinación de Medicamentos , Carne/análisis , Resistencia al Corte , Cloruro de Sodio/análisis , Porcinos , Temperatura
18.
J Sci Food Agric ; 96(5): 1467-73, 2016 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-25953510

RESUMEN

BACKGROUND: Adenosine 5'-monophosphate (AMP) is often used in meat and poultry soups as a flavor enhancer (flavor modifier), or as food additives for specific nutritional purposes. Our previous research as well as evidence from others showed that actomyosin could be dissociated into myosin and actin by AMP in extracted muscle solution. However, there is no report available on the application of AMP to dissociate actomyosin and to improve meat tenderness. The objectives of this study were to evaluate the effect of AMP on duck meat tenderness and other quality traits and to explore the mechanism of the action of AMP on meat tenderness. RESULTS: Duck breast muscle was treated with 0, 10, 20, 30, 40 mmol L(-1) AMP at 5 °C for 10 h and examined for shear force, microstructure, actomyosin dissociation, myofibril fragmentation index (MFI), pH, water content, cooking loss, CIE* color (L*, a*, b*), inosine monophosphate (IMP) and free amino acid (FAA) contents. Results showed that shear force, cooking loss, L* and b* of the muscles significantly decreased after AMP treatment (P < 0.05); actomyosin dissociation, MFI, pH, water content, fiber diameter, sarcomere length, IMP and ammonia significantly increased (P < 0.05); no significant change in a* or other FAA content was observed (P > 0.05), and muscle shrinkage in transverse and longitudinal directions were restrained after AMP treatment. CONCLUSION: The results suggest that AMP could notably improve meat tenderness, and this effect was probably mainly through increasing muscle pH, promoting actomyosin dissociation and disrupting the Z-line; meanwhile, the conversion of AMP to IMP may contribute to the flavor of meat.


Asunto(s)
Adenosina Monofosfato/farmacología , Patos , Carne/análisis , Actomiosina/efectos de los fármacos , Animales , Fenómenos Químicos , Aditivos Alimentarios , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/ultraestructura , Músculo Esquelético/química , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/ultraestructura , Miofibrillas/efectos de los fármacos , Valor Nutritivo , Sarcómeros/efectos de los fármacos , Sarcómeros/ultraestructura , Gusto
19.
J Food Prot ; 78(12): 2200-6, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26613915

RESUMEN

This study evaluated the antibacterial effect of the combination of ε-polylysine (ε-PL) and nisin against Enterococcus faecalis strains. The combination of ε-PL and nisin showed synergistic antibacterial activity against three Enterococcus strains. Scanning electron microscopy and a membrane permeability assay revealed that the combined treatment with ε-PL and nisin synergistically damaged the cell morphology of E. faecalis strain R612Z1 cells. Both ε-PL and nisin can dissipate the transmembrane electric potential of E. faecalis R612Z1 cells, but these peptides did not affect the transmembrane pH gradient. The combination of ε-PL and nisin can produce a high reactive oxygen species level in E. faecalis R612Z1 cells. The results indicated that the uptake of ε-PL into cells was promoted through nisin and that the combination of ε-PL and nisin could produce a high reactive oxygen species level in E. faecalis R612Z1 cells, leading to cell growth inhibition.


Asunto(s)
Antibacterianos/farmacología , Enterococcus faecalis/efectos de los fármacos , Conservación de Alimentos/métodos , Nisina/farmacología , Polilisina/farmacología , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Pared Celular , Manipulación de Alimentos , Industria de Alimentos , Concentración de Iones de Hidrógeno , Potenciales de la Membrana/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Permeabilidad , Especies Reactivas de Oxígeno/metabolismo
20.
J Food Prot ; 78(5): 940-5, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25951388

RESUMEN

The effect of NaCl stress (0 to 8%, wt/vol) on the growth and tyramine production in two Enterococcus faecalis strains was examined during culture time. The growth of E. faecalis was inhibited by the increase in NaCl concentration, but tyramine production was unaffected. Tyramine accumulated rapidly during the logarithmic phase of the strains, and the final tyramine levels were approximately 800 µg/ml. Relative gene expression of four genes in the tyrosine decarboxylase locus, namely, tyrRS, tyrDC, tyrP, and nhaC, was evaluated at different incubation times. The results showed that NaCl stress could upregulate the expression of tyrDC and tyrP to improve the tyramine production of a single E. faecalis strain under certain conditions, and TyrS could act as a negative regulator on the genetic regulation of the tyramine cluster.


Asunto(s)
Enterococcus faecalis/metabolismo , Cloruro de Sodio/metabolismo , Tiramina/biosíntesis , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Enterococcus faecalis/enzimología , Enterococcus faecalis/genética , Enterococcus faecalis/crecimiento & desarrollo , Tirosina Descarboxilasa/genética , Tirosina Descarboxilasa/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...