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1.
Int J Biol Macromol ; 258(Pt 2): 128981, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38158064

RESUMO

This investigation aims to highlight the applicability of a potent eco-friendly developed composite film to combat the Escherichia coli biofilm formed in a model food system. ZnO nanoparticles (NPs) synthesized using green methods were anchored on the surface of cellulose nanocrystals (CNCs). Subsequently, nano-chitosan (NCh) solutions were used to disperse the synthesized nanoparticles and cinnamon essential oil (CEO). These solutions, containing various concentrations of CNC@ZnO NPs and CEO, were sequentially coated onto cellulosic papers to inhibit Escherichia coli biofilms on grey zucchini slices. Six films were developed, and Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, biodegradation, and mechanical properties were assessed. The film containing 5 % nano-emulsified CEO + 3 % dispersed CNC@ZnO nano-hybrid in an NCh solution was selected for further testing since it exhibited the largest zone of inhibition (34.32 mm) against E. coli and the highest anti-biofilm activity on biofilms developed on glass surfaces. The efficacy of the film against biofilms on zucchini surfaces was temperature-dependent. During 60 h, the selected film resulted in log reductions of approximately 4.5 logs, 2.85 logs, and 1.57 logs at 10 °C, 25 °C, and 37 °C, respectively. Applying the selected film onto zucchini surfaces containing biofilm structures leads to the disappearance of the distinctive three-dimensional biofilm framework. This innovative anti-biofilm film offers considerable potential in combatting biofilm issues on food surfaces. The film also preserved the sensory quality of zucchini evaluated for up to 60 days.


Assuntos
Quitosana , Óleos Voláteis , Óxido de Zinco , Quitosana/química , Antibacterianos/farmacologia , Escherichia coli , Cinnamomum zeylanicum/química , Óxido de Zinco/química , Óleos Voláteis/farmacologia , Biofilmes
2.
Food Chem ; 425: 136493, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37285628

RESUMO

The purpose of this study was to prepare a porous intelligent aerogel for food packaging applications, in particular for monitoring minced beef freshness, using cellulose extracted from grape stalk, Salep as a copolymer, and red grape anthocyanins as a pH-sensitive pigment. Aerogels based on cellulose 1% (w/v) and Salep 1% (w/v) at ratios of 1:3, 3:1, and 1:1 were prepared by lyophilization. Aerogel with high porosity, low density, and higher mean pore size was chosen for preparing intelligent colorimetric aerogel (ICA) with the addition of 0.44 mg/100 mL of anthocyanins. Based on the color parameters, the stability of ICA was satisfactory when exposed to both light and dark conditions, as well as when stored at either 4 or 25 °C. Additionally, X-ray diffraction and thermogravimetric analyses indicated that an amorphous aerogel was formed, with a thermal decomposition temperature of 320 °C. The color of the ICA changed from purple on the first and 3rd days of packaging to blue-gray on the 6th day. As the spoilage process continued, the color of the indicator became dark brown. Taken together, ICA showed a quick response to minced beef spoilage with the ability to differentiate between fresh and spoiled meat during storage at 4 °C.


Assuntos
Celulose , Vitis , Animais , Bovinos , Antocianinas , Embalagem de Alimentos , Polímeros , Concentração de Íons de Hidrogênio
3.
Int J Biol Macromol ; 244: 125356, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37321442

RESUMO

Novel antimicrobial emitting aerogels based on starch/cellulose/Thymus daenensis Celak essential oil (SC-TDEO) were developed and optimized for antimicrobial packaging of Koopeh cheese. An aerogel formulation containing cellulose (1 %; extracted from sunflower stalks) and starch (5 %) in a 1:1 ratio was selected for in vitro antimicrobial assay and subsequent cheese application. The minimum inhibitory dose (MID) of TDEO in the vapor phase against Escherichia coli O157:H7 was determined by loading various concentrations of TDEO onto the aerogel, and an MID of 256 µL/Lheadspace was recorded. Aerogels containing TDEO at 25 × MID and 50 × MID were then developed and used for cheese packaging. During a 21-day storage period, cheeses treated with SC-TDEO50 MID aerogel exhibited a significant 3-log reduction in psychrophile counts and a 1-log reduction in yeast-mold counts. Moreover, significant changes in the population of E. coli O157:H7 were observed in cheese samples. After 7 and 14 days of storage with SC-TDEO25 MID and SC-TDEO50 MID aerogels, the initial bacterial count became undetectable, respectively. Sensory evaluations indicated that the samples treated with SC-TDEO25 MID and SC-TDEO50 aerogels received higher scores compared to the control group. These findings demonstrate the potential of the fabricated aerogel to develop antimicrobial packaging suitable for cheese applications.


Assuntos
Anti-Infecciosos , Queijo , Escherichia coli O157 , Queijo/microbiologia , Contagem de Colônia Microbiana , Celulose , Anti-Infecciosos/farmacologia , Microbiologia de Alimentos
4.
Int J Biol Macromol ; 153: 240-247, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32145233

RESUMO

An intelligent freshness indicator was developed by immobilizing anthocyanins of black carrot (ABC) within the starch matrix (total anthocyanins content of 10 mg/100 mL) to monitor freshness/spoilage of milk. The microstructural, spectral, swelling and solubility properties as well as color stability (as a function of time, temperature and light) of the indicator at different pHs were characterized. The incorporation of ABC did not change the swelling index and water solubility. The prepared label showed visible color changes as a function of pH and excellent color stability after one month storage at different conditions. The total color difference (TCD) value of the indicator corresponded to the pH, acidity, and microbial growth of the pasteurized milk. The Pearson correlation coefficient showed a high correlation between TCD and pH (R = -0.979), while a high and positive correlation between TCD and acidity as well as TMC (R = 0.983 and 0.968, respectively) was observed. The developed label can discriminate fresh milk form the milk entered into the initial (TCD: 7.8 after 24 h) and final (TCD: 34.8 after 48 h) steps of spoilage. The fabricated label opens a new perspective to use anthocyanins-incorporated biopolymers in the milk intelligent packaging as a simple and easy-to-use freshness indicator.


Assuntos
Antocianinas/química , Daucus carota/química , Armazenamento de Alimentos , Leite/química , Amido/química , Animais , Colorimetria , Concentração de Íons de Hidrogênio , Leite/microbiologia , Solubilidade
5.
Adv Pharm Bull ; 7(4): 621-628, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29399552

RESUMO

Purpose: The aim of this study was to investigate antimicrobial and biofilm removal potential of Zataria multiflora essential oil (ZEO) and silver nanoparticle (SNP) alone and in combination on Staphylococcus aureus and Salmonella Typhimurium and evaluate the mechanism of action. Methods: The minimum inhibitory concentration (MIC), and optimal inhibitory combination (OIC) of ZEO and SNP were determined according to fractional inhibitory concentration (FIC) method. Biofilm removal potential and leakage pattern of 260-nm absorbing material from the bacterial cell during exposure to the compounds were also investigated. Results: MICs of SNP for both bacteria were the same as 25 µg/ mL. The MICs and MBCs values of ZEO were 2500 and 1250 µg/mL, respectively. The most effective OIC value for SNP and ZEO against Salm. Typhimurium and Staph. aureus were 12.5, 625 and 0.78, 1250 µg/ mL, respectively. ZEO and SNP at MIC and OIC concentrations represented a strong removal ability (>70%) on biofilm. Moreover, ZEO at MIC and OIC concentrations did a 6-log reduction of primary inoculated bacteria during 15 min contact time. The effect of ZEO on the loss of 260-nm material from the cell was faster than SNP during 15 and 60 min. Conclusion: Combination of ZEO and SNP had significant sanitizing activity on examined bacteria which may be suitable for disinfecting the surfaces.

6.
Clin Neurol Neurosurg ; 151: 37-42, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27764706

RESUMO

OBJECTIVES: Despite the progress in understanding acute pain physiology during recent decade, eighty percent of patients still suffer from post-operative discomfort. Pregabalin is an anticonvulsant agent that is approved for painful neuropathies in diabetic patients and post herpetic neuralgia. The main objective of the present study was to compare the improvement in post-operative pain management and patient lifestyle in 3 groups, as first group received placebo, second who received Pregabalin for one day and the last group those who received it for 14 days. METHODS: This was a prospective single center, randomized, triple-blind, 3-arm, parallel group study. In this triple-blind study, patients were randomized to 1 of 3 groups using computer-generated random number table. 1) The first group received placebo for 14 days, the second group received Pregabalin 300mg 8h preoperatively and 150mg 12 and 24h postoperatively and for the rest of 13days received placebo and the third group received Pregabalin 300mg eight hours preoperatively and 15mg every 12h postoperatively for 14 days. Name, age, gender, height, weight, education, duration of pain, past medical history, drug history,total morphine requirement at the time of discharge and MRI findings of all the patients were recorded, also they Numerical scale system (NRS) and Oswestry low back pain disability index (ODI) questionnaire were completed for them. All the patients were operated based on standard surgery techniques, bilateral foramenotomy and interlaminar discectomy. RESULTS: Of the 105 patients who entered the run-in period, 47 patients (44.8%) were female and 58 (55.2%) were male. The Patients radicular pain mean score based on NRS estimated before surgery was 7.22±1.95 in pregabalin14, 7.71±1.84 in pregabalin1 and 7.45±1.9 in control group. There were no statically significant differences between three groups (P-Value>0.05). The Patients back pain mean score based on NRS was 5.2±2.87 in pregabalin14, 5.11±3.23 in pregabalin1 and 6.4±3.06 in control group. This means that there were no significant differences in the overall score among those three groups (P-Value>0.05). In comparison to their preoperative pain, the average radicular pain in each group of patients improved significantly 4, 8, 12 and 24h after the operation (P-Value<0.001), but there were no significant differences in radicular pain improvements comparing three groups. CONCLUSION: The results of this study indicate that 1day and 2 weeks post-operative 300mg pregabalin administration may not improve acute pain, morphine consumption and quality of life of patients after surgery. It seems that the diseases cause chronic pain that requires long-term treatment with higher doses.


Assuntos
Analgésicos/farmacologia , Discotomia/efeitos adversos , Vértebras Lombares/cirurgia , Avaliação de Resultados em Cuidados de Saúde , Dor Pós-Operatória/tratamento farmacológico , Pregabalina/farmacologia , Adolescente , Adulto , Idoso , Analgésicos/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pregabalina/administração & dosagem , Adulto Jovem
7.
Pathol Res Pract ; 208(2): 100-3, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22293278

RESUMO

Survivin expression is correlated with suppression of apoptosis in human solid tumors. A polymorphism at position -31 (G/C) (rs 9904341) has been associated with cancer risk in several studies. We evaluated the correlation of this polymorphism with the risk of papillary thyroid carcinoma (PTC) in an Irananian population. The cases consisted of patients with PTC (n=123) and normal controls, composed of non-related healthy people (n=131). The frequency of GC or CC genotype in patients with PTC was significantly higher than in the controls [GC+CC vs GG, p=0.02 OR; 1.7, 95%CI (1.05-3.04)]. There was a significant difference between patients with more aggressive clinical manifestations, including lymphatic involvement compared to the controls [GC+CC vs GG, p=0.0006, OR; 3.7, 95%CI (1.6-9.2)]. The presence of C allele was significantly associated with the presence of more profound manifestations, including lymph node involvement, vascular involvement and multifocality.


Assuntos
Proteínas Inibidoras de Apoptose/genética , Polimorfismo Genético , Neoplasias da Glândula Tireoide/genética , Adulto , Carcinoma , Carcinoma Papilar , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Irã (Geográfico) , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fenótipo , Medição de Risco , Fatores de Risco , Survivina , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/patologia
8.
J Sci Food Agric ; 91(15): 2850-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21796636

RESUMO

BACKGROUND: The effectiveness of chitosan films containing Zataria multiflora Boiss essential oil (ZEO) (5 and 10 g kg(-1) ) and grape seed extract (GSE) (10 g kg(-1) ) on lipid oxidation and microbial (lactic acid bacteria, aerobic mesophiles and inoculated Listeria monocytogenes) characteristics of mortadella sausage at 4 °C for 21 days was evaluated. The release of total phenolics (TPs) into sausage was also assessed. RESULTS: All films exhibited antibacterial activity against L. monocytogenes on agar culture media. Chitosan films containing ZEO were the most effective on the growth of bacteria. The growth of L. monocytogenes was significantly inhibited by ZEO-GSE containing films especially during storage of the sausages for 6 days. Aerobic mesophiles and lactic acid bacteria were the most sensitive and resistant groups to films by 0.1-1.1 and 0.1-0.7 log cycles reduction, respectively. Sausages wrapped by 10 g kg(-1) GSE + 10 g kg(-1) ZEO films had the lowest degrees of lipid oxidation, which was 23% lower than the control. The TPs of ZEO films decreased to zero after 6 days, whereas TPs of GSE films followed a slight decrease during the storage. CONCLUSION: Antimicrobial/antioxidant chitosan film could be developed by incorporating GSE and ZEO for extending the shelf life of mortadella sausage.


Assuntos
Conservação de Alimentos/métodos , Extrato de Sementes de Uva/farmacologia , Lamiaceae/química , Peroxidação de Lipídeos/efeitos dos fármacos , Produtos da Carne , Óleos Voláteis/farmacologia , Vitis/química , Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Bactérias/crescimento & desenvolvimento , Quitosana , Fast Foods , Microbiologia de Alimentos , Embalagem de Alimentos , Armazenamento de Alimentos , Produtos da Carne/microbiologia , Fenóis/farmacologia , Refrigeração , Suínos
9.
Molecules ; 13(6): 1263-74, 2008 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-18596653

RESUMO

Chitosan (CS) was prepared from Artemia urmiana cyst shells using the same chemical process as described for the other crustacean species, with minor adjustments in the treatment conditions. The influence of modifications of the CS production process on the physiochemical and functional properties of the CS obtained was examined. The study results indicate that Artemia urmiana cyst shells are a rich source of chitin as 29.3-34.5% of the shell's dry weight consisted of this material. Compared to crab CS (selected as an example of CS from a different crustacean source) Artemia CS exhibited a medium molecular weight (4.5-5.7 x10(5) Da), lower degree of deacetylation (67-74%) and lower viscosity (29-91 centiposes). The physicochemical characteristics (e.g., ash, nitrogen and molecular weight) and functional properties (e.g., water binding capacity and antibacterial activity) of the prepared Artemia CSs were enhanced, compared to control and commercial samples, by varying the processing step sequence.


Assuntos
Artemia/química , Indústria Química/métodos , Quitosana/química , Quitosana/isolamento & purificação , Acetilação , Animais , Peso Molecular , Viscosidade , Molhabilidade
10.
Pak J Biol Sci ; 10(22): 4103-7, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19090287

RESUMO

During the years 2005 and 2006, samples of raw and of pasteurized milk (72 samples each) were collected randomly from various parts of Urmia city in Iran for the detection of aflatoxin M1. Aflatoxin M1 levels were assessed by Enzyme Linked Immuno Sorbent Assay (ELISA). There was a high incidence of AFM1 (100%), in both raw and pasteurized milk samples. The AFM1 levels in 6.25% of samples were higher than the maximum tolerance limit accepted by European Union (50 ng L(-1)), while the observed mean ofAFM1 was lower than those proposed for European diets. Maximum level ofAFM1 in raw and pasteurized samples were 91.8 and 28.5 ng L(-1), while minimum levels were 4.3 and 5.1 ng L(-1), respectively. The levels ofAFM1 in total samples indicated that feeds for cows in this region were contaminated with AFB1 in such a level that appears to be a serious public health problem at the moment. Therefore, there is a need to limit exposure to aflatoxins by imposing regulatory limits.


Assuntos
Aflatoxina M1/análise , Ensaio de Imunoadsorção Enzimática/métodos , Contaminação de Alimentos , Animais , Carcinógenos/análise , Bovinos , Irã (Geográfico) , Leite , Mutagênicos/análise , Temperatura
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