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1.
J Sep Sci ; 47(5): e2300070, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38466171

RESUMEN

Herein, a deep eutectic solvent (DES)-based miniaturized pressurized liquid extraction in combination with DES-based dispersive liquid-liquid microextraction (DLLME) was developed for the extraction of organophosphorus pesticides (parathion-methyl, triazophos, parathion, diazinon, and phoxim) from egg powder samples prior to their analysis by a high-performance liquid chromatography-diode array detector. In this work, first, the analytes' extraction was done by a pressurized liquid phase extraction for effective extraction of the analytes from the solid matrix, and then they were concentrated on a DLLME for more concentration of the analytes to reach low limits of detections. The use of DESs was done in both steps to omit the use of toxic organic solvents. Satisfactory results including high extraction recoveries (74-90%), great repeatability (relative standard deviations equal or less than 4.3% and 5.3% for intra- and inter-day precisions), and low limits of detection (0.11-0.29 ng/g) and quantification (0.38-0.98 ng/g) were attained under the optimum conditions. Lastly, the suggested approach was utilized for the determination of the studied pesticides in various egg powder samples marketed in Tabriz, Iran.


Asunto(s)
Microextracción en Fase Líquida , Paratión , Residuos de Plaguicidas , Plaguicidas , Compuestos Organofosforados , Cromatografía Líquida de Alta Presión , Disolventes Eutécticos Profundos , Polvos
2.
J Sep Sci ; 46(20): e2300149, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37712114

RESUMEN

Herein, a modified quick, easy, cheap, effective, rugged, and safe extraction was developed based on deep eutectic solvent for the extraction of several pesticides from canola oil samples. In this work, first, different sorbents were selected to remove the sample interferences, and the composition of the sorbents was optimized by simplex centroid design. The extracted analytes were more concentrated by solidification of floating deep eutectic solvent droplet-dispersive liquid-liquid microextraction. Low limits of detection (0.15-0.23 ng/g) and quantification (0.49-0.76 ng/g), high extraction recoveries (74-87%) and enrichment factors (224-263), and good repeatability (relative standard deviation equal to or less than 5.1 and 4.7% for intra- and interday precisions, respectively) were achieved using the proposed method. The suggested approach was used for the quantification of the analytes in different canola oil samples. Additionally, the effects of microwave irradiations exposure and sonication in decontamination of the samples were evaluated. In this method, there was no need for centrifugation and toxic solvents. Also, effective extraction of the analytes and minimizing interferences were achieved through the use of various sorbents.

3.
J Sep Sci ; 46(10): e2200893, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36864003

RESUMEN

In the present work, a combination of microwave-assisted extraction with magnetic ionic liquid-based dispersive liquid-liquid microextraction was developed for the extraction of chloramine-T from fish samples. In this method, the sample was mixed with a hydrochloric acid solution and exposed to microwave irradiations. By doing so, chloramine-T was converted to p-toluenesulfonamide and extracted from the sample into an aqueous phase. Then, a mixture of acetonitrile (as a dispersive solvent) and magnetic ionic liquid (as an extraction solvent) was rapidly injected into the obtained solution. In the following, the magnetic solvent droplets including the extracted analytes were isolated from the aqueous solution in the presence of an external magnetic field and after diluting with acetonitrile injected into high-performance liquid chromatography equipped with a diode array detector. Under the optimum extraction conditions, high extraction recovery (78%), low limits of detection (7.2 ng/g) and quantification (23.9 ng/g), good repeatability (relative standard deviations ≤5.8 and 6.8% for intra- and inter-day precisions, respectively), and wide linear range (23.9-1000 ng/g) were obtained. Finally, various fish samples marketed in Tabriz city (East Azarbaijan, Iran) were analyzed with the suggested method.


Asunto(s)
Líquidos Iónicos , Microextracción en Fase Líquida , Animales , Cromatografía Líquida de Alta Presión , Microondas , Acetonitrilos , Peces , Iones , Solventes
4.
J Sep Sci ; 46(16): e2300068, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37407502

RESUMEN

In this study, for the first time, a deep eutectic solvent-based microwave-assisted extraction was combined with ionic liquid-based temperature controlled liquid phase microextraction for the extraction of several aflatoxins from cheese samples. Briefly, the analytes are extracted from cheese sample (3 g) into a mixture of 1.5 mL choline chloride:ethylene glycol deep eutectic solvent and 3.5 mL deionized water by exposing to microwave irradiations for 60 s at 180 W. The liquid phase was taken and mixed with 55 µL 1-hexyl-3-methylimidazolium hexafluorophosphate. By cooling the solution in the refrigerator centrifuge, a turbid state was obtained and the analytes were extracted into the ionic liquid droplets. The analytes were determined by high-performance liquid chromatography equipped with fluorescence detector. Low limits of detection (9-23 ng kg-1 ) and quantification (30-77 ng kg-1 ), high extraction recovery (66%-83%), acceptable enrichment factor (40-50), and good precision (relative standard deviations ≤ 5.2%) were obtained using the offered approach. These results reveal the high extraction capability of the method for determination of aflatoxins in the cheese samples. In this method, there was no need for organic solvents and it can be considered as green extraction method.


Asunto(s)
Queso , Líquidos Iónicos , Microextracción en Fase Líquida , Microextracción en Fase Líquida/métodos , Disolventes Eutécticos Profundos , Microondas , Temperatura , Solventes/química , Límite de Detección
5.
J Sep Sci ; 45(21): 3974-3984, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36106365

RESUMEN

A simple pretreatment method based on the combination of microwave-assisted extraction and dispersive micro solid phase extraction has been developed for the extraction of eprinomectin, doramectin, ivermectin, and abamectin from cow meat, liver, and kidney samples. The extracted drugs were determined using high-performance liquid chromatography equipped with a diode array detector. In this method, the solid samples were mixed with deionized water and organic solvent mixture, and the resulting mixtures were exposed to microwave irradiations to accelerate the analytes' extraction from the samples into the solution. Then, the supernatant was taken and mixed with a mixture of three sorbents optimized by a simplex centroid design. After vortexing and centrifuging, the sorbent particles were isolated and the adsorbed analytes onto the sorbent surface eluted with a natural deep eutectic solvent for more concentration. After centrifuging, the supernatant was taken and injected into the separation system. Acceptable repeatability (relative standard deviations ≤7.0%), high extraction recoveries (72%-86%) and enrichment factors (216-258), and low limits of detection and quantification (0.06-0.10 and 0.19-0.32 ng/g, respectively) were acquired. The method was successfully applied for the assessment of the analytes in the mentioned samples and ivermectin was found in three samples.


Asunto(s)
Microextracción en Fase Líquida , Animales , Bovinos , Microextracción en Fase Líquida/métodos , Microondas , Antiparasitarios , Ivermectina , Extracción en Fase Sólida/métodos , Solventes/química , Carne , Riñón , Hígado
6.
J Sep Sci ; 44(2): 576-584, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33151627

RESUMEN

A solid-phase extraction method combined with deep eutectic solvent-based dispersive liquid-liquid microextraction has been developed for the extraction of three antibiotics in honey samples prior to their determination by ion mobility spectrometry. In this method, first, a multiwall carbon nanotube/urea-formaldehyde nanocomposite was synthesized using co-precipitation polymerization method and then it was used as a sorbent for the analytes extraction from the samples. After that the adsorbed analytes were eluted from the sorbent using a water-miscible organic solvent. The collected elution solvent was mixed with tetrabutylammonium chloride:butanol deep eutectic solvent and the mixture was applied in the following microextraction method. The method provided low limits of detection and quantification in the ranges of 0.32-0.86 and 1.1-2.9 ng/g, respectively. The method had a proper repeatability expressed as relative standard deviation less than or equal to 9.1%. The validated method was successfully performed on different honey samples obtained from different producers.


Asunto(s)
Antibacterianos/análisis , Miel/análisis , Microextracción en Fase Líquida , Residuos de Plaguicidas/análisis , Extracción en Fase Sólida , Adsorción , Butanoles/química , Formaldehído/química , Nanotubos de Carbono/química , Tamaño de la Partícula , Compuestos de Amonio Cuaternario/química , Solventes/química , Propiedades de Superficie , Urea/química
7.
Indian J Med Res ; 150(1): 87-91, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31571634

RESUMEN

Background & objectives: Diarrhoeagenic Escherichia coli strains are common agents of diarrhoea particularly in developing countries. Food products of animal origin are considered as common carriers of E. coli. This study was undertaken to identify enterotoxigenic Escherichia coli (ETEC) and enteropathogenic E. coli (EPEC) pathotypes in animal-source foods (ASF). Methods: A total of 222 ASF samples were investigated. Based on the culture and biochemical tests, 109 E. coli isolates were identified. Duplex-polymerase chain reaction assay was used to detect ETEC and EPEC. The target genes selected for each category were the lt and st for the ETEC, and eae and bfp for the EPEC isolates. Results: The occurrence of E. coli in dairy and meat products was 45 and 52.5 per cent, respectively. Among the E. coli isolates, two ETEC, one typical EPEC and three atypical EPEC were detected in meat samples, whereas only one typical EPEC and one atypical EPEC were detected in dairy samples. Interpretation & conclusions: Our results showed presence of ETEC and EPEC strains in ASFs. The milk without pasteurization and traditional dairy products produced in unhygienic conditions are most likely the main sources of E. coli pathotypes and other zoonotic pathogens and thus can be considered a potential hazard to the health of the community.


Asunto(s)
Diarrea/microbiología , Escherichia coli Enteropatógena/aislamiento & purificación , Escherichia coli Enterotoxigénica/aislamiento & purificación , Microbiología de Alimentos , Animales , Bovinos , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Diarrea/diagnóstico , Diarrea/genética , Escherichia coli Enteropatógena/patogenicidad , Escherichia coli Enterotoxigénica/patogenicidad , Heces/microbiología , Enfermedades Transmitidas por los Alimentos/epidemiología , Enfermedades Transmitidas por los Alimentos/microbiología , Humanos , Irán/epidemiología , Leche/microbiología , Reacción en Cadena de la Polimerasa , Serotipificación
8.
Int J Biol Macromol ; 277(Pt 3): 134506, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39106931

RESUMEN

Starch nanoparticles (SNPs) have been used in food emulsions as natural stabilizer and emulsifier. SNPs in colloidal form were produced using enzymatically, acidic and alkaline hydrolyses in combination to ultrasonication and precipitation methods. X-Ray diffraction test for produced SNPs indicated that enzymatically and acidic prepared SNPs had amorphous structure while, the resulted SNPs using alkaline hydrolysis had lower relatively crystallinity. Results indicated that, enzymatically prepared SNPs, had minimum particle size (225 ± 10 nm) and polydispersity index (0.472 ± 0.05), and maximum zeta potential (-26.3 ± 1 mV), antioxidant activity (3.36 ± 0.05 %) and specific surface area (1.8 ± 0.1 m2g-1). Transmission electron microscopy revealed that prepared SNPs had spherical shape and enzymatically prepared SNPs had mean particle size of <100 nm. SNPs in powder form were prepared using freeze drying (pressure and temperature of 100 Pa and - 70 °C). Atomic force microscopy results demonstrated that starch granules had smooth surface, with polyhedral shape and particle size ranging 5 to 25 µm, and after hydrolysis, SNPs had particle size in nanometer scale. Emulsion ability test indicated that oil separation time from the prepared emulsions containing 10 % (W/V) starch, and enzymatically, acidic and alkaline prepared SNPs powder were 41, 70, 82 and 101 s, respectively.


Asunto(s)
Liofilización , Nanopartículas , Tamaño de la Partícula , Almidón , Almidón/química , Nanopartículas/química , Hidrólisis , Antioxidantes/química , Sonicación/métodos , Difracción de Rayos X , Precipitación Química
9.
Infect Genet Evol ; 123: 105638, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39002873

RESUMEN

Understanding the prevalence and distribution of CRISPR-Cas systems across different strains can illuminate the ecological and evolutionary dynamics of Clostridium botulinum populations. In this study, we conducted genome mining to characterize the CRISPR-Cas systems of C. botulinum strains. Our analysis involved retrieving complete genome sequences of these strains and assessing the diversity, prevalence, and evolution of their CRISPR-Cas systems. Subsequently, we performed an analysis of homology in spacer sequences from identified CRISPR arrays to investigate and characterize the range of targeted phages and plasmids. Additionally, we investigated the evolutionary trajectory of C. botulinum strains under selective pressures from foreign invasive DNA. Our findings revealed that 306 strains possessed complete CRISPR-Cas structures, comprising 58% of the studied C. botulinum strains. Secondary structure prediction of consensus repeats indicated that subtype II-C, with longer stems compared to subtypes ID and IB, tended to form more stable RNA secondary structures. Moreover, protospacer motif analysis demonstrated that strains with subtype IB CRISPR-Cas systems exhibited 5'-CGG-3', 5'-CC-3', and 5'-CAT-3' motifs in the 3' flanking regions of protospacers. The diversity observed in CRISPR-Cas systems indicated their classification into subtypes IB, ID, II-C, III-B, and III-D. Furthermore, our results showed that systems with subtype ID and III-D frequently harbored similar spacer patterns. Moreover, analysis of spacer sequences homology with phage and prophage genomes highlighted the specific activities exhibited by subtype IB and III-B against phages and plasmids, providing valuable insights into the functional specialization within these systems.


Asunto(s)
Sistemas CRISPR-Cas , Clostridium botulinum , Evolución Molecular , Genoma Bacteriano , Clostridium botulinum/genética , Filogenia , Bacteriófagos/genética , Plásmidos/genética
10.
Food Sci Nutr ; 12(5): 3735-3744, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38726418

RESUMEN

Flaxseed oil has a high amount of α-linolenic acid (an ω3 essential fatty acid), but it is very prone to oxidation. Therefore, olive leaves were used as a rich source of phenolic compounds with flaxseeds upon oil extraction by cold press to enhance the oxidative stability of extracted oils. Oil from flaxseeds with unblanched leaves and blanched leaves at level of (0 [control sample], 2.5, 5, 7.5, and 10% w/w) was extracted by cold press. Quality of extracted oils was evaluated for 90 days of storage at room condition. Incorporation of unblanched olive leaves could increase the acid value of the extracted oils up to 2.0 (mg KOH/g oil) compared to the other samples. Oxidation of the flaxseed oil could be delayed by the addition of blanched olive leaves up to 5%. Oil extracted from flaxseeds incorporated with blanched olive leaves had higher content of carotenoids (up to 33.7 mg/kg oil), chlorophylls (up to 35.7 mg/kg oil), and phenolic compounds (up to 200 mg/kg oil). Also, oxidative stability of extracted oils was higher up to 7.5% of blanched olive leaves (11.4 h) compared to control sample (7.2 h) and other oil samples. Polyunsaturated fatty acids of the oil samples were well preserved by the incorporation of blanched olive leaves. Based on the obtained results, incorporation of suitable amount of blanched olive leaves (up to 7.5%) with flaxseeds before oil extraction by press can be an appropriate procedure to produce oils with high content of bioactive components and suitable oxidative stability.

11.
Foods ; 12(11)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37297457

RESUMEN

This study investigated the effects of two mild thermal processing (MTP) (63 °C, 40 °C, 3 min) methods, in a brine storage medium (7-16% (w/v) NaCl) and a vinegar solution (5% vinegar, 1% salt, and 0.5% sugar), on some physicochemical properties of truffles (Terfezia claveryi). Weight loss, phenolic compounds, firmness, ascorbic acid and microbial loads were evaluated during 160 days of storage. It was demonstrated that a 5% vinegar treatment with 63 °C MTP was effective to reduce the weight loss, microbial spoilage and increased firmness and of truffles during storage. However, phenolic compounds and ascorbic acid content were decreased by heating. Both MTPs inhibited the microbial load, but the 63 °C, 3 min MTP was most effective and resulted in an immediate (3.05-3.2 log CFU/g) reduction in the total aerobic bacteria (TAB) and remained at an acceptable level during storage, while the 40 °C, 3 min MTP reduced (1.12-2 log CFU/g) of the TAB. The results of this study suggest that the 63 °C MTP and immersion in 5% vinegar increased the shelf life of the truffles without perceptible losses in quality attributes.

12.
Food Sci Nutr ; 11(6): 3404-3413, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37324881

RESUMEN

Royal jelly, due to its unique bioactive components, has special biological activities, but a great extent of its nutritional value is lost during processing and storage. Lyophilization, an effective preservation technique, can feasibly preserve the main bioactive compounds present in royal jelly. In this study, fresh royal jelly was subjected to the freeze-drying process at a pressure and temperature of 100 Pa and - 70°C, respectively, for 40 h. The results obtained indicated that the pH, turbidity, total phenol content, and antioxidant activity of the royal jelly powder (RJP), during 3 months of storage at ambient temperature (30°C), were constant with values of 4.30, 1.634 (%A.U.), 0.617 (g/L), and 28.7 (%), respectively. Moisture content of the prepared RJP was less than 1%, while that of the fresh royal jelly was 70%. Furthermore, for the fresh royal jelly, the mentioned parameters were significantly (p < .05) decreased after 2 months of storage at freezer temperature (-20°C). GC-MS analysis indicated that the amount of 10-hydroxy-2-decanoic acid (10H2DA) in RJP was 3.85 times more than that of fresh royal jelly. The obtained results also indicated that prepared RJP had a high bactericidal effect toward Escherichia coli and Staphylococcus aureus, with clear zone diameters of 12 and 15 mm, respectively. The present study provides a foundation for research on the potential application of prepared RJP and the development of dietary supplements and functional foods.

13.
Sci Rep ; 13(1): 7813, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-37188770

RESUMEN

Potential probiotic Enterococcus faecalis KUMS-T48, isolated from a kind of Iranian traditional dairy product (Tarkhineh), was assessed for its anti-pathogenic, anti-inflammatory and anti-proliferative properties against HT-29 and AGS cancer cell lines. This strain showed strong effects on Bacillus subtilis and Listeria monocytogenes and moderate effect on Yersinia enterocolitica, while indicated weak effect on Klebsiella pneumoniae and Escherichia coli. Also, neutralizing the cell-free supernatant and treating it with catalase and proteinase K enzymes reduced the antibacterial effects. Similar to Taxol, the cell-free supernatant of E. faecalis KUMS-T48 inhibited the in vitro proliferation of both cancer cells in a dose-dependent manner, but unlike Taxol, they had no activity against normal cell line (FHs-74). Pronase-treatment of the CFS of E. faecalis KUMS-T48 abrogated its anti-proliferative capacity, thereby showing the proteinaceous nature of the cell-free supernatant. Further, induction of apoptosis-based cytotoxic mechanism by E. faecalis KUMS-T48 cell-free supernatant is related to anti-apoptotic genes ErbB-2 and ErbB-3, which is different from Taxol's apoptosis induction (intrinsic mitochondria apoptosis pathway). Also, as evidenced by a decline in interleukin 1ß inflammation-promoting gene expression and a rise in the anti-inflammatory interleukin-10 gene expression in the HT-29 cell line, probiotic E. faecalis KUMS-T48 cell-free supernatant demonstrated a significant anti-inflammatory impact.


Asunto(s)
Neoplasias , Probióticos , Humanos , Enterococcus faecalis , Irán , Apoptosis , Células HT29 , Paclitaxel/farmacología , Probióticos/farmacología , Antiinflamatorios/farmacología , Antiinflamatorios/metabolismo
14.
Food Sci Technol Int ; 28(3): 257-272, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33874757

RESUMEN

Essential oils with antimicrobial or antioxidant activities have received extensive attention among customers, manufacturers, and food scientists, especially with rising worries about the safety of synthetic food preservatives. However, like other functional lipid compounds their incorporation into aqueous systems is challenging, due to their less water solubility. Furthermore, their susceptibility to light, moisture, heat, and oxygen origins their less chemical and structural stabilities. Consequently, the present research was aimed to encapsulate the thyme essential oil into nanoliposomes, using a thin layer hydration-sonication technique, which can be a proficient solution for revealed problems. The effects of phospholipid and stabilizing agents' concentrations, namely, lecithin, cholesterol, and glycerol, as main formulation parameters were investigated on characteristics of gained nanoliposomes, using a response surface method. Various empirical models were also developed to predict product characteristics by changing the formulation parameters. According to the numerical multiple optimizations, the best thyme oil nanoliposomes can be gained using equal concentrations of all three components as 1% with a mean particle size of 189.6 nm, PDI of 0.3487, the net zeta-potential of 42.48 mV, and DPPH radical scavenging of 12.72%. The prepared nanoliposomes had acceptable physical but limited chemical stabilities. The antibacterial action of manufactured essential oil nanoliposomes against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus has made them efficient candidates as natural food preservatives.


Asunto(s)
Aceites Volátiles , Thymus (Planta) , Antibacterianos/farmacología , Conservantes de Alimentos/farmacología , Aceites Volátiles/farmacología , Staphylococcus aureus , Thymus (Planta)/química
15.
Z Naturforsch C J Biosci ; 77(9-10): 395-402, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-35230753

RESUMEN

Artemia urumiana is bisexual population of the Lake Urmia of Iran. Its biomass was freeze dried and using its lyophilized powder, hydro-alcoholic extract was prepared and utilized in gold nanoparticles (Au NPs) synthesis. Six different Au NPs fabrication methods namely: microwave heating, hydrothermal, ultraviolet (UV) irradiation, ultrasonication, common heating using conventional heating, and self-assembling were utilized for Au NPs synthesis using A. urumiana extract. Gas chromatography analysis indicated that the prepared extract were contained numerous fatty acid methyl esters such as Hexadecanoic acid methyl ester. Results indicated that the formed NPs using heater and stirrer, and UV irradiation had minimum particle size of 25 and 94 nm, respectively. However, as compared to the formed Au NPs using heater and stirrer technique, UV irradiation fabricated Au NPs with high zeta potential value of -32.5 mV and small polydispersity value of 0.310. Results also demonstrated that the synthesized Au NPs using heater and stirrers, and UV irradiation had highest antioxidant activities of 13.7 and 11.9%, and bactericidal effects against Escherichia coli and Staphylococcus aurous bacteria strains, as compared to other fabricated Au NPs using other methods. There were insignificant (p > 0.05) differences between these two attributes of the formed Au NPs.


Asunto(s)
Oro , Nanopartículas del Metal , Animales , Antibacterianos/química , Antibacterianos/farmacología , Artemia , Escherichia coli , Oro/química , Nanopartículas del Metal/química , Extractos Vegetales/química , Extractos Vegetales/farmacología
16.
J AOAC Int ; 105(3): 827-834, 2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-34904627

RESUMEN

BACKGROUND: Ultrafiltration cheese is produced in large scale from treated pasteurized milk with mesophilic starter, and to expand its shelf life, preservatives addition is needed. OBJECTIVE: The purpose of the present study was preparation of encapsulate Spirulina platensis algae nanoliposomes to evaluate the characteristics of the nanoliposomes loaded with Spirulina extract (SE-NLs). In addition, the chemical and microbiological properties of white cheese produced with SE-NLs were studied. METHOD: Nanoliposomes are composed of lecithin and cholesterol, used for the encapsulation of SE. The SE-NLs were prepared using the thin-layer hydration method. The characteristics of produced SE-NLs including particle size, zeta potential, morphology, and the encapsulation efficiency were studied during 4 weeks in different storage conditions (4°C and 25°C). In addition, the effect of SE and SE-NLs on the chemical and microbiological properties of white cheese was evaluated during 60 days of ripening. RESULTS: The results showed that the nanoliposomes loaded with 3 mg/g of SE had the optimum formulation due to the higher EE, smaller particle size, and higher negatively charged zeta potential. The quality of the produced nanoliposomes decreased by increasing the time of storage, but the SE-NLs stored at 4°C were more stable and possessed higher EE and smaller particle sizes. While the chemical composition of the cheeses manufactured by the nanoliposome loaded with 3 mg/g SE-NLs were comparable to that of control cheese at 60 days of ripening, it showed a significant inhibitory effect on Staphylococcus aureus and Listeria monocytogenes after 30 days. CONCLUSIONS: The utilization of SE-NLs can be considered a natural antimicrobial and an alternative to the use of synthetic preservatives in the production of white cheese. HIGHLIGHTS: Nanoliposomes of Spirulina platensis extracts were prepared. Ultrafiltration white cheese prepared by nanoliposomes then was evaluated.


Asunto(s)
Queso , Listeria monocytogenes , Spirulina , Animales , Queso/microbiología , Leche , Extractos Vegetales/química
17.
Meat Sci ; 187: 108750, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35217393

RESUMEN

The present investigation deals with the textural properties, colloidal interactions, and morphology of emulsified meat systems in the presence of flaxseed flour (FF) and tomato powder (TP). The results displayed that the emulsifying capacity and texture of raw and cooked meat batters were significantly affected following the addition of TP and FF. The cooked emulsified sausages containing 3% of FF and 3% (w/w) of TP showed the highest values for hardness and cohesiveness, as compared to the control and 6% (w/w) of FF samples. The outcomes of mechanical shearing forces and SEM showed the formation of a gel-type matrix around the unabsorbed protein in TP-FF batters. These patterns were then confirmed by the higher values of GN° (van Gurp Palmen) associated with an increase in the elasticity and the molecular entanglement. In contrast, large fat globules, low entanglement, and protein cross-linking were observed in meat batters with 6% FF.


Asunto(s)
Lino , Productos de la Carne , Solanum lycopersicum , Color , Harina , Carne , Productos de la Carne/análisis , Polvos
18.
Anal Methods ; 13(14): 1747-1756, 2021 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-33861242

RESUMEN

In this study, a pH-induced solidification of floating organic droplet homogeneous liquid-liquid microextraction procedure using deep eutectic solvent decomposition was developed for the extraction of five pyrethroid insecticides from milk samples prior to their analysis by using a gas chromatography-flame ionization detector. To reach this goal, the sample was transferred into a glass test tube and its proteins were precipitated with trichloroacetic acid. After centrifugation, the supernatant phase was transferred into another test tube and a few microliters of menthol: p-aminophenol deep eutectic solvent were dissolved in the solution and shaken to obtain a homogeneous solution. Then a few microliters of ammonia solution were added to the solution and the mixture was sonicated to break down the homogeneous solution. By doing so, the deep eutectic solvent was decomposed and menthol was formed throughout the solution as tiny droplets. In the following, the tube was transferred into an ice bath to solidify the extraction solvent on the solution surface. The collected phase was removed and melted at room temperature and an aliquot of it was analyzed by using a determination system. The validation outcomes confirmed that the method provides high extraction recoveries (72-84%) and high enrichment factors (257-299) with acceptable repeatability (relative standard deviations ≤6.4%). Low limits of detection (1.1-2.4 ng mL-1) and quantification (3.6-8.1 ng mL-1) were obtained using this approach. Finally, several milk samples were analyzed and deltamethrin was successfully determined in some samples.


Asunto(s)
Microextracción en Fase Líquida , Plaguicidas , Piretrinas , Animales , Concentración de Iones de Hidrógeno , Leche/química , Plaguicidas/análisis , Solventes
19.
Meat Sci ; 161: 107957, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31785513

RESUMEN

The present study investigates the chemical properties and sensory attributes of beef sausages which have been incorporated with three tomato powder levels (0, 1.5 and 3%) and three flaxseed powder levels (0, 3 and 6%). All samples were stored at 4 °C for 42 days. The addition of tomato and flaxseed powders decreased (P < .001) L* values, pH, residual nitrite and moisture contents and increased b* value (P < .001), protein, carbohydrate, ash, fiber and total calories contents. The nitrite content decreased during the storage time. Linolenic acid increased with the addition of flaxseed powder. Generally, adding tomato and flaxseed powders up to 3% had no effect (P > .05) on the sensory evaluation parameters on cooked and fried sausages. Based on the obtained results, it is possible to produce sausages incorporated with tomato and flaxseed powders and introduce to the market as a new processed meat product.


Asunto(s)
Lino , Manipulación de Alimentos/métodos , Calidad de los Alimentos , Productos de la Carne/análisis , Carne Roja/análisis , Solanum lycopersicum , Animales , Bovinos , Almacenamiento de Alimentos , Concentración de Iones de Hidrógeno , Nitritos/análisis , Polvos , Agua/análisis
20.
Anal Methods ; 12(34): 4220-4228, 2020 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-32812538

RESUMEN

In this study, a combination of homogeneous liquid-liquid extraction and dispersive liquid-liquid microextraction based on solidification of a deep eutectic solvent has been utilized as an efficient method for the extraction of three widely used antibiotics (oxytetracycline, penicillin G, and tilmicosin) from sausage samples. In this method, initially the antibiotics are extracted from the powdered sausage sample into acetonitrile and then, to concentrate the analytes and achieve a high sensitivity, the obtained acetonitrile is mixed with an extraction solvent (a newly synthesized water-immiscible deep eutectic solvent with a melting point near room temperature), and the obtained mixture is rapidly injected into deionized water. In the next step, the mixture is transferred into an ice bath and the solidified extraction solvent containing the analytes is removed and dissolved in ACN. For quantitative analysis, this phase is taken and injected into an ion mobility spectrometer which operated in the positive mode and is equipped with a continuous corona discharge ionizer. This instrumental technique characterizes molecules based on the gaseous phase mobility of their ions formed at ambient pressure and under an electric field. Under the optimum conditions, limits of detection and quantification were achieved in the ranges of 1.52-2.73 and 5.1-9.1 ng g-1, respectively. The relative standard deviations were less than 8% for intra- (n = 6) and inter-day (n = 4) precisions at a concentration of 20 ng g-1 of each analyte. Finally, the proposed method was applied to the analysis of the studied antibiotics in fifteen different sausage samples marketed in Tabriz, Iran. Oxytetracycline was determined in three of the studied sausage samples.


Asunto(s)
Microextracción en Fase Líquida , Antibacterianos , Espectrometría de Movilidad Iónica , Irán , Extracción Líquido-Líquido , Solventes
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