Explore the vast range of titles available.

A simplistic approach is presented for the synthesis of ultrasonically fabricated graphene oxide functionalized with polyaniline and N-[3-(Trimethoxysilyl)propyl]ethylenediamine. The synthesized nanocomposite was then employed for the facile, green, ultrasound-assisted, magnetic dispersive solid-phase extraction of amoxicillin, ampicillin, and penicillin G in milk samples and infant formula prior to high-performance liquid chromatography-ultraviolet determination. The designed nanocomposites were comprehensively characterized using field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy. In order to achieve the best extraction efficiencies, the influential parameters including pH, amount of magnetic sorbent, type and volume of elution solvent, extraction time, sample volume, and desorption time were assessed. At the optimum conditions, linear ranges of 2.5–1000 (μg L −1 ) for ampicillin and penicillin G and a linear range of 2.5–750 (μg L −1 ) were obtained for amoxicillin at optimum conditions. Moreover, the limits of detection ( S / N  = 3) of 0.5, 0.8, and 0.9 (μg L −1 ) were obtained for amoxicillin, ampicillin, and penicillin G, respectively. The precision (relative standard deviations (%)) values of 3.1, 2.6, and 2.5 at the concentration of 50 μg L −1 for seven replicates were obtained for ampicillin, amoxicillin, and penicillin G, respectively. The efficiencies of ≤ 96% and relative standard deviations of less than 3.1% were also obtained thereby confirming the high potential of the synthesized nanocomposites for simultaneous preconcentration and separation of the β-lactam antibiotics in complex matrixes. Graphical Abstract

Date kernel as a functional food component has a special importance due to its rich nutritional profile, low price, and ease of access. For this, in this research, the sub‐product was used for formulation of semi‐prepared dry soup (SPDS); the effect of adding 0 (S1 = control), 2 (S2), and 4 (S3) %w/w date kernel powder (DKP) on physicochemical, nutritional, and organoleptic properties and beneficial effects of SPDS samples were evaluated. The results revealed that S2 and S3 samples were different from the control sample in some physicochemical properties so that viscosity increased 1.27 and 1.52 times and a* raised 5.6 and 8.5 times, respectively, while L* decreased 0.94 and 0.88 times and b* reduced 0.92 and 0.8 times, respectively. The nutritional properties of S2 and S3 samples compared with the control sample improved. Also, differences were observed in the beneficial effects of S2 and S3 compared with the control sample as total polyphenol content (TPC) increased 1.06 and 1.11 times, respectively (p < .05); antioxidant activities (AA) of S2 and S3 samples were 8.04 and 6.01 mg/ml and angiotensin‐converting enzyme (ACE) inhibitory activities were measured to be 8.2 and 7.86 mg/ml, respectively; also, α‐amylase and α‐glucosidase inhibitory activities of S2 and S3 samples were observed 4.48% and 5.70%, and 4.59% and 6.36%, respectively. From the organoleptic aspect, S3 had the highest acceptability. Generally, it is concluded that with the addition of DKP (maximally 4%w/w) to SPDS formulation, a functional soup could be produced considering the rich nutritional profile of DKP. Date kernel powder (DKP) could be considered as the potential functional ingredient in healthy food products. DKP improved α‐amylase and α‐glucosidase and antioxidant activities of semi‐prepared and dry soup (SPDS). SPDS with improved nutritional properties was provided using DKP incorporation.

Diclofenac (DCF) as a non-steroidal pharmaceutical has been detected in aquatic samples more than other compounds due to its high consumption and limited biodegradability. In this study, ultrasound waves were applied along with an advanced nano-Fenton process (US/ANF) to remove DCF, and subsequently, the synergistic effect was determined. Before that, the efficiency of the US and ANF processes was separately studied. The central composite design was used as one of the most applicable responses surface method techniques to determine the main and interactive effect of the factors influencing DCF removal efficiency in US/ANF. The mean DCF removal efficiency under different operational conditions and at the time of 1–10 min was obtained to be about 4%, 83%, and 95% for the US, ANF, and US/ANF, respectively. Quadratic regression equations for two frequencies of US were developed using multiple regression analysis involving main, quadratic, and interaction effects. The optimum condition for DCF removal was obtained at time of 8.17 min, H/F of 10.5 and DCF concentration of 10.12 at 130 kHz US frequency. The synergy index values showed a slight synergistic effect for US/ANF (1.1). Although the synergistic effect of US/ANF is not very remarkable, it can be considered as a quick and efficient process for the removal of DCF from wastewater with a significant amount of mineralization.

The purpose of this research was to investigate the effect of bioactive peptides isolated from soy whey on the physicochemical, sensory, and microbiological characteristics of yogurt during storage. Trypsin was utilized to hydrolyze soy whey protein at 45°C for 4 h. Then, the resulting protein hydrolysate was fractionated using reversed phase‐high performance liquid chromatography (RP‐HPLC). Since the F7 fraction showed the best antioxidant and antibacterial capabilities, different levels (6.5, 13, and 17 mg/mL) of this peptide fraction were added to yogurt. A control sample (without the bioactive peptide) was also prepared. Yogurt samples were stored for 3 weeks. With the increase in peptide concentration, the antioxidant activity of yogurt increased while viscosity and syneresis decreased (p < .05). During storage, yogurt acidity, syneresis, and viscosity increased while pH and antioxidant activity declined (p < .05). The addition of bioactive peptide reduced the quantity of Escherichia coli and Staphylococcus aureus bacteria in yogurt during storage (p < .05), and the reduction in bacterial quantity was stronger as the peptide content was increased. The sample containing the largest concentration of peptide (17 mg/mL) got the lowest overall acceptability score. The level of 13 mg/mL of the peptide was chosen as the best concentration for yogurt fortification in terms of overall acceptance and functional properties. Therefore, soy whey‐derived peptide can be utilized as a functional component as well as a natural preservative in yogurt. Since soy whey is a cost‐effective source of peptides and little research has been done on peptides derived from this by‐product, the aim of this study was to isolate and purify bioactive peptides from this by‐product and use them as a natural preservative in a model food system (yogurt). The fraction with the highest antimicrobial and antioxidant activity which was added to yogurt showed a good antibacterial effect against Escheirichia coli and Staphylococcus aureus. Moreover, the addition of this peptide improved the physicochemical quality of yogurt. Therefore, this bioactive peptide can be used as a natural alternative to common preservatives in the food industry.

Staphylococcus aureus is most common causes of hospital-acquired infections and food-associated disease. In the last years, sensing platform based on fluorescence- nanomaterials and nanocomposites have been attracted a great attention for detection of bacteria and macromolecules. In this study, a new modified mesoporous silica SBA-15 with ZnO and Au nanoparticles (SBA-15@ZnO/Au) was prepared to enhance the photoluminescence emission of SBA-15 matrix and investigate the potential use as a nano probe for detection of S. aureus bacteria. Au nanoparticles were added to the SBA-15 after loading ZnO nanoparticles and the SBA-15@ZnO/Au nanocomposite was successfully fabricated. The Structural, morphological, physicochemical and optical properties of the prepared samples have been studied. The low-angle X-ray diffraction (XRD) pattern showed highly ordered two-dimensional hexagonal lattice of SBA-15 and the wide-angle XRD pattern proved the formation of ZnO and Au nanoparticles. The results of the Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis showed that the prepared nanocomposite have a regular two dimensional hexagonal structure with cylindrical channels even after loading ZnO and Au nanoparticles. According to Nitrogen adsorption–desorption isotherm measurement, the pore diameter and the specific surface area of SBA-15@ZnO/Au nanocomposite have been obtained 3.15 nm and 604.19 m 2 /g. Photoluminescence (PL) spectra of bare SBA-15@ZnO/Au nanocomposite showed three peaks at central wavelength of 410, 500 and 750 nm arising from electron transfer process and radiative decay of collective plasmonic states. After addition of S. aureus bacteria, the nano probe-target complex was formed and the PL re-emission at 640 nm and quenching of PL emissions at 750 and 410 nm was observed. Furthermore, the new nanocomposite was demonstrated to have the proper sensitivity toward bacteria concentrations. The results can open promising prospect for this nanocomposite as a nano probe for detection of S. aureus in the UV–Visible region of electromagnetic spectrum.

Drinking water quality can be deteriorated by microbial and toxic chemicals during transport, storage and handling before using by the consumer. This study was conducted to evaluate the microbial and physicochemical quality of drinking water from bottled water coolers. A total of 64 water samples, over a 5-month period in 2012-2013, were collected from free standing bottled water coolers and water taps in Isfahan. Water samples were analyzed for heterotrophic plate count (HPC), temperature, pH, residual chlorine, turbidity, electrical conductivity (EC) and total organic carbon (TOC). Identification of predominant bacteria was also performed by sequence analysis of 16S rDNA. The mean HPC of water coolers was determined at 38864 CFU/ml which exceeded the acceptable level for drinking water in 62% of analyzed samples. The HPC from the water coolers was also found to be significantly (P < 0.05) higher than that of the tap waters. The statistical analysis showed no significant difference between the values of pH, EC, turbidity and TOC in water coolers and tap waters. According to sequence analysis eleven species of bacteria were identified. A high HPC is indicative of microbial water quality deterioration in water coolers. The presence of some opportunistic pathogens in water coolers, furthermore, is a concern from a public health point of view. The results highlight the importance of a periodic disinfection procedure and monitoring system for water coolers in order to keep the level of microbial contamination under control.

The presence of bioactive peptides has already been reported in many foods such as milk, fermented products, plant and marine proteins. Bioactive peptides are sequences between 2 and 20 amino acids that can inhibit chronic diseases by modulating and improving physiological functions, so these peptides contribute in holding the consumer health. Also, bioactive peptides can affect pro-health or functional properties of food products. Fractionation of the protein hydrolysate revealed a direct relationship between their structure and functional activity. So, this review focuses on different factors effecting on bioactive peptide structures, biological and functional properties such as antihypertensive, antioxidative, hypocholesterolemic, water-holding capacity, foaming capacity, emulsifying properties and solubility. Also, this review looks at the identified bioactive peptides from food protein sources as potential ingredients of health promoting functional foods.

Fluoride is an essential element for human health. However, excess fluoride in drinking water may cause dental and/or skeletal fluorosis. Drinking water is the main route of fluoride intake. The aim of the present study was to measure fluoride levels in human breast milk collected from two regions of Golestan Province, northern Iran with different amount of fluoride concentration of drinking water in Bandar Gaz and Nokande cities and to correlate it with fluoride concentrations in drinking water used by mothers living in these two areas. Twenty samples of water were collected from seven drinking water wells during 2012 from Bandar Gaz and Nokande in Iran during 2012. Fluoride concentration of water samples was measured using SPADNS method. Sixty breast milk samples were collected from lactating mothers of Bandar Gaz and Nokande cities. Content in breast milk was determined using standard F ion-selective electrode. Spearman's rho correlation analysis was used to assess any possible relationship between fluoride levels in breast milk and in drinking water. The means and standard deviation for F concentration in breast milk and drinking water were 0.002188±0.00026224 ppm and 0.5850±0.22542 ppm, respectively. Analysis of data showed that the variables were not normally distributed so the Spearman correlation coefficient between two variables calculated (ρ S = 0.65) and it was significant (P=0.002). Fluoride concentration in water can directly act on its concentration in breast milk. We speculate that modifying F concentration in water can affect accessibility of fluoride for infants.

Using sodium bicarbonate (SB) in cooking meat products is a controversial subject. The aim of this study was to estimate an effect of different SB concentrations on the quality characteristics and organoleptic properties of meat in Kubideh Kebab, an Iranian popular meat product. Ground meat was divided into four groups (a, b, c, and d). After that, SB was added in ratio 0.25, 0.50, 1.00, and 2.00 g/kg respectively. A sample without SB was considered as a blank sample. The Kebab samples were prepared and cooked properly at 350°C for 4–6 minutes and at 450°C for 2–4 minutes. A significant difference was observed in the pH values and the cooking loss between the blank sample and those Kebab samples that were cooked at 350°C and 450°C and pre-treated with SB in the amount of 0.25–2.00 g per 1 kg of meat (P < 0.05). The amount of residual bicarbonate ions increased significantly in the cooked Kebab samples at both treatment temperatures in the a-d group in comparison with the blank sample, as well as between the groups (P = 0.00). The organoleptic properties did not change in the a-d groups in comparison with the blank sample.

Ultrasound-assisted magnetic nanofluid-based liquid-phase microextraction was coupled to GC-MS in a method for simultaneous determination of the pyrethroid insecticides permethrin, deltamethrin, and cypermethrin. A highly efficient extraction solvent called “magnetic nanofluid (MNF)” is introduced for preconcentration of pyrethroids. The MNF consists of magnetic multiwalled carbon nanotubes (MMWCNTs) and deep eutectic solvent. Following microextraction, the MNF was detached by an external magnet from the medium without the need for centrifugation. 2-Pyridinecarboxamide, choline chloride, and anhydrous ferric chloride were used for the synthesis of the deep eutectic solvent. The effects of pH value, volume of MNF, sonication time, sample volume, and ionic strength, type and amount of back extraction solvent were investigated. Under optimum conditions of MNF volume of 50 μL, time of 5 min, 100 μL acetone as back extraction solvent, NaCl concentration of 1 mol.L −1 and sample volume of 30 mL, the detection limits are 2.8, 2.7 and 2.0 ng·mL −1 for permethrin, deltamethrin and cypermethrin, respectively. The linear response ranges are between 0.01 and 250 ng·mL −1 , and relative standard deviations (for n  = 7) are 3.5, 3.2 and 2.8%. The method was successfully applied to the determination of trace levels of permethrin, deltamethrin and cypermethrin in (spiked) milk samples. Graphical abstract Schematic representation of ultrasound assisted magnetic nanofluid-based liquid phase microextraction separation/preconcentration of permethrin, deltametrin, and cypermethrin residues in milk using GC-MS.