A Novel Fluorescent DNA Sensor for Acrylamide Detection in Food Samples Based on Single-Stranded DNA and GelRed.

The presence of acylamide (AA) in large group of food products and its health hazards have been confirmed by scientists. In this study, a simple and innovative biosensor for AA determination was designed based on single-stranded DNA (ssDNA) with partial guanine and GelRed. The idea of this biosensor is based on the formation of AA-ssDNA adduct through the strong binding interaction between AA and guanine base of ssDNA, which subsequently inhibits the interaction of ssDNA and GelRed, leading to a weak fluorescence intensity. The binding interaction between AA and ssDNA was confirmed by UV-Vis absorption spectrometry and fluorescence intensity. Under optimum conditions, the designed biosensor exhibited excellent linear response in range of 0.01-95 mM, moreover it showed high selectivity toward AA. The limit of detection was 0.003 mM. This biosensor was successfully applied for the determination of AA in water extract of potato fries and coffee in the range of 0.05-100 mM with LOD of 0.01 mM and 0.05-95 mM with LOD of 0.004 mM, respectively.

Effect of different extraction methods on antioxidant properties and encapsulation efficiency of anthocyanin of pomegranate peel.

This study aimed to measure the efficiency, total anthocyanin content (TAC), and total phenol content (TPC) of pomegranate peel powder (PPP) extract from different extractions. Also, the characteristics of the nanoencapsulated extracts with maltodextrin (MD)/Lepidium perfoliatum (Qodume Shahri) seed gum were investigated. The highest and lowest extraction efficiency was related to solvent ethanol-water extraction (SEWE) (76.35%) and solvent ethanol extraction (SEE) (25.73%), respectively. Extracts obtained from microwave extraction (ME) and ultrasound extraction (UE) methods had the highest and lowest values of TAC (4.00-0.35) (mg C3G/g PPP) and TPC (702.13-232.58) (mg GAE/100 g sample), respectively. Peak 3213 in FT-IR indicates the O-H bond, which showed the highest content of phenolic compounds in the extract obtained from ME compared with SEE, SEWE, and UE. The nanoencapsulated extracts from SEE, SEE, and UE had the lowest particle size of peak 1, particle distribution in peak 1, and average particle size distribution compared with other extractions, respectively. The highest encapsulation efficiency of anthocyanin (EEA) and encapsulation efficiency of phenol (EEP) were related to UE (96.15%) and SEWE (86.57%), respectively. The EEP and EEA of SEE were not significantly different from ME and SEWE, respectively. On the other hand, the type and amount of extractive compounds in the extract have a great impact on the efficiency of nanoencapsulation and the average size distribution of nanoencapsulated particles. As a result, PPP extract is rich in antioxidant compounds, which can be determined by carefully examining the appropriate method of extraction and preservation of the extracted compounds.

Surface analysis and thermal behavior of the functionalized cellulose by glutaric anhydride through a solvent-free and catalyst-free process.

According to the 12 principles of green chemistry, surface functionalization was performed using glutaric anhydride under solvent-free and catalyst-free conditions. FTIR spectra and DS analyses demonstrated the functionalization of HCl-hydrolyzed cellulose. The influence of two parameters, i.e., the glutaric anhydride concentration and the reaction time, on the functionalization of HCl-hydrolyzed cellulose was investigated. Protocol efficiency was studied by a degree of substitution (DS). It was found that higher concentrations of glutaric anhydride cause an enhancement of DS to 0.75 and 0.87 for GA3-12 and GA9-12, respectively. In addition, the longer reaction time increased zeta potential from -12.2 ± 1.7 for G9-6 to -34.57 ± 2.2 for GA9-12. Morphology analysis by SEM showed a decrease in fiber length for the functionalized cellulose. DSC profiles confirmed dehydration at a range of 17 to 134 °C. A glass transition was revealed at -30 to -20 °C for all studied samples. The fusion, the depolymerization of cellulose chains, the cleavage of glycosidic linkages, and the decomposition of the crystalline parts of cellulose occur at 195 to 374 °C. Therefore, an efficient and greener process was developed to functionalize the HCl-hydrolyzed cellulose by glutaric anhydride, a safe and non-toxic anhydride, in the absence of the solvent and catalyst.

Ultra-stable high internal phase emulsions stabilized by protein-anionic polysaccharide Maillard conjugates.

This paper reports the production of O/W high internal phase emulsions (HIPEs) using protein-anionic polysaccharide Maillard conjugates. First, Maillard conjugates were prepared from soy protein isolate (SPI) or sodium caseinate (SC) proteins and Alyssum homolocarpum seed gum (AHSG) or kappa-carrageenan (kC) polysaccharides. The conjugation process was confirmed and monitored by UV spectrophotometry, Fourier transform infrared, circular dichroism, fluorescence spectroscopies, and differential scanning calorimetry. Under the optimized reaction conditions, SC-AHSG conjugates exhibited the highest glycation degree and emulsifying properties. Next, HIPEs were made using the optimized conjugates, and their microstructure, droplet size, and physical stability were evaluated. The emulsion stabilized by SC-AHSG conjugate had the lowest mean droplet size (363.07 ± 34.56 nm), orderly-packed oil droplets with monomodal distribution, the highest zeta potential (-27.70 ± 0.70 mV), high storage stability (no creaming or oil-off) and was ultra-stable against environmental stresses. Results of this research are helpful for development of emulsion-based foods with novel functionality.

Preparation and characterization of a novel biodegradable film based on sulfated polysaccharide extracted from seaweed Ulva intestinalis.

Seaweeds can be a suitable, inexpensive, abundant, and renewable source for the production of biodegradable films as an alternative to plastics. Sulfated polysaccharides, which are abundant in Ulva intestinalis seaweed, have shown important biological activities such as anticoagulant, antioxidant, antitumor, anti-inflammatory, and antiviral activities. Mechanical, physicochemical, barrier, and surface properties of sulfated polysaccharide films extracted from Ulva intestinalis using glycerol and polyethylene glycol (PEG) as plasticizers were studied. Ulva intestinalis sulfated polysaccharide films (USP films) were successfully prepared by the incorporation of three concentrations of plasticizers (30, 40, and 50%). The film properties depended on the type and concentration of the plasticizer. Based on the results, by increasing the concentration of the plasticizer, the thickness, moisture content, solubility, and elongation at break of the USP films increased and tensile strength, young's modulus, transparency, and barrier properties of the films decreased. The film plasticized with 30% PEG showed the highest value of tensile strength (36.95 MPa), and the lowest value for permeability to vapor water and oxygen were 1.9 g mm-1 s-1kPa-1 × 10-11 and 7.45 cm-3.cm/cm2.s.cmHg ×10-8, respectively. Scanning electron microscopy (SEM) observations indicated that the surface of the films was free of bubbles, cracks, or fractures. Fourier transform infrared (FTIR) spectroscopy results revealed some interactions between plasticizers and the polymer.

Monitoring of new coronavirus (SARS-CoV-2): Origin, transmission, and food preservation methods.

Unfortunately, there is limited research on coronavirus survival of food products and also food processing. The knowledge of the physical and chemical characteristics of coronaviruses mostly comes from the study of SARS-CoV and MERS-CoV physical (i.e., thermal processing, chilling and freezing, microwave irradiation, ultraviolet light, gamma irradiation, high hydrostatic pressure) and chemical (acidification and use of common disinfectants in the food industry like chlorinated derivatives and ozone) are means which could be used to inactive the coronaviruses or reduce the infection. These methods can be applied individually or in combination to act better performance. Thermal processing is one of the most effective methods for inactive coronavirus. Heating at 75°C (15-60 min) and 65°C (1 min) was the best temperature for inactive SARS-CoV and MERS virus, respectively. Among irradiation methods (microwave, UV, and gamma), the most effective one is UVC rays. Moreover, the use of disinfectant like chlorinated derivatives is appropriate way to disinfect food product surfaces. Novelty impact statement: This review provided updated information on effective strategies for inactive coronavirus that can be used in the food industry. SARS-CoV-2 as a new pandemic coronavirus was initiated from contaminated foods and can be transmitted by close contact, aerosols, and food surfaces. Food preservation (physical and chemical) methods could decrease SARS-CoV-2. Probably, heating and UVC are the most effective approach to inactive SARS-CoV-2. Despite the findings of coronavirus inactivation which were here discussed, much research is still needed for the development of new approaches to overcome the coronavirus.

Investigation of hot air and foam-mat dried cress seed gum by FT-IR, zeta potential, steady shear viscosity, dynamic oscillatory behavior, and other physical properties.

The effects of different drying methods (hot air drying at 40, 60, and 80°C, and foam-mat drying) on the characteristics (FT-IR, zeta potential, conductivity, color, rheology, texture, and emulsifying) of extracted cress seed gum (CSG) have been investigated. The models described the rheological behavior of CSG with high R 2, but in general Herschel-Bulkley's model has higher values of R 2 and lower values of RMSE compared to the fitted models. The HD 80 has high amount of viscosity. This means that as the temperature rises, the gel network is getting stronger, and gums from the internal CSG sections have a stronger gel network. Results of strain sweep test demonstrated that storage ( G LVE ' ) and loss modulus ( G LVE ″ ) for all solutions except foam-mat drying in the linear area showed solid-like behavior. The parameters of strain sweep (Gf, τf, τy, G LVE ″ , G LVE ' , YLVE) increased with increasing temperatures. Frequency sweep test showed that storage ( G LVE ' ) was greater than loss modulus ( G LVE ″ ) and samples have a solid behavior but foam-mat drying exhibited liquid behavior. Increasing temperature has a direct impact on texture, so hardness and adhesion are increased consequently. Generally, CSG has good emulsifying and foaming characteristics, but no significant difference was observed.

Frying stability of canola oil supplemented with ultrasound-assisted extraction of Teucrium polium.

In this study, antioxidant activity and protective effects of Teucrium polium extract in stabilizing of canola oil during frying were tested and compared to synthetic antioxidant, BHA. Total phenolic, α-tocopherol, flavonoid, and condensed tannin content of Teucrium polium extracted by ethanol ultrasound-assisted were 60.90 mg/g, 103.66 µg/ml, 4.36 mg/g, and 3.77 mg/g, respectively. Moreover, IC50 of the extract was 924.21 ppm. Canola oil samples containing 200, 600, and 1,000 ppm of the extract were heated at 180˚C for 30 hr and compared with BHA. Progress of oil oxidation was determined by measuring their peroxide value (PV), acid value (AV), iodine value (IV), carbonyl value (CV), color index (CI), conjugated diene value, and total polar compounds (TPC). The results showed that the extract was capable of retarding oil oxidation and deterioration significantly (p < .05) at all concentrations during frying. So, Teucrium polium extract can be used as natural antioxidant to retard oil oxidation.

Influence of different salts on rheological and functional properties of basil (Ocimum bacilicum L.) seed gum.

In this paper, the influence of a variety of salts (NaCl, CaCl2, and KCl) at different concentrations (0, 0.1, 0.5 and 1% w/w) on rheological and functional properties of basil seed gum (BSG) were investigated. BSG produced a high viscosity solution with yield stress, which was a function of salt type and concentration. In all samples, viscosity decreased as the electrostatic interactions between the BSG chains altered by salts. Flow behavior index increased by salt addition, which shows BSG had weaker shear-thinning behavior and worse mouthfeel in the presence of salts. The viscoelasticity of BSG strongly influenced by the addition of salt type as well as concentration. Larger cations (Ca+2) shield the electrostatic interaction between BSG chains more strongly compared to smaller cations as they have larger hydrated radius. As a result divalent salts decreased the viscosity and viscoelasticity more significantly. Emulsion capacity improved by salts addition, especially at high concentrations of salts. The foam capacity increased in the presence of CaCl2 and KCl increased foaming capacity of BSG. The results suggest that the addition of the different types of salt can alter or modify the rheological and functional properties of BSG, depending on the salt concentration.

Changes in chemical composition and biological activity of essential oil from Thomson navel orange (Citrus sinensis L. Osbeck) peel under freezing, convective, vacuum, and microwave drying methods.

Thomson navel orange peel is a by-product of citrus processing, which contains high levels of bioactive compounds advantageous to human health, nevertheless due to its high moisture content it is exceedingly perishable. Drying is among the most common preservation methods, which could prolong the plants shelf-life via reducing their moisture value. Taking this into account, depending on their type and conditions, drying techniques could degrade plant heat-sensitive metabolites and lead to quality decline. Therefore, the goal of this paper was to investigate the influence of seven drying methods named sun, shade, oven, vacuum oven, microwave, and freeze-drying with different drying conditions on the physical properties, for example, bulk density and color (L*, a*, b*, ΔE, and browning index (BI)) and essential oil characteristics such as extraction yield, chemical composition, antioxidant (total phenolic content (TPC), DPPH, and FRAP essays), and antimicrobial (MIC and MBC) activities of Thomson peel and determine the superior drying procedure. Results showed that freeze-dried sample had the highest retention of L* (48.54) and b* (49.00) values, lowest BI (216.11) as well as highest EO extraction yield (6.90%), TPC (60.10 GAE/100 g), FRAP (0.52% at 80 mg/ml), and lowest IC50 (5.00 mg/ml), MIC and MBC compared with other drying treatments. Therefore, it could be inferred that freeze-drying is the most efficient drying approach in respect of preserving both physical and EO attributes of Thomson peel.

Flow behavior, thixotropy, and dynamic viscoelasticity of ethanolic purified basil (Ocimum bacilicum L.) seed gum solutions during thermal treatment.

During processing, foodstuffs may be treated at various thermal operations. Thus, this study investigated the functional properties and flow behavior at operation conditions to ensure safety and improve quality and stability at high temperatures and analyzed the ability of gum to be used in food formulation. The results showed that the purified basil seed gum (PBSG) solutions could beknown as non-Newtonian liquids with pseudoplastic behavior. Frequency sweep revealed the storage modulus (G') was higher than the loss modulus (G″) in the treatments. According to stress sweep, frequency sweep, complex viscosity (η *), and loss-tangent (tan δ) outcomes, mechanical spectra of PBSG were categorized as weak gels. Besides, concentration and temperature were effect on G' and G″. The results indicated that, in general, 1% PBSG-121°C had the maximum yield stress, consistency coefficient (k), extent of thixotropy, and the minimum values of flow behavior index. Also, 1% PBSG showed the highest G', G″, η *, yield stress values at the limit of the LVE range (τy), flow-point stress (τf), and corresponding modulus G f (G' = G″), and the lowest value of tan δ. Exhibiting distinctive rheological characteristics of PBSG makes it as a worthy hydrocolloid to use in food products, which use thermal processing.

Bioactive compounds, antioxidant and antimicrobial activities of Arum maculatum leaves extracts as affected by various solvents and extraction methods.

The different species of Arum maculatum plant can be found in all over the world, and a wide range of medicinal applications has been mentioned for them. Thus, it can also be valued as a source of natural compounds with antioxidant and antimicrobial activities. In this study, the effect of solvents (water, ethanol, ethanol:water (50:50)) and extraction methods (maceration and ultrasound) on the extraction yields and bioactive properties of extracts were analyzed. The antioxidant capacity of Arum maculatum leaves extracts was investigated, and the concentrations of total phenolics, tocopherols, tannins and flavonoids were determined. 1,1-diphenyl 2-picrylhydrazyl free radical (DPPH), ß-Carotene bleaching, and oxidative stability index (OSI) were used to determine antioxidant activity. The ability to scavenge radicals was measured in these experiments by the discoloration of the solution. Also, the antimicrobial activity of different extracts against Gram-positive (Staphylococcus aureus and Listeria monocytogenes) and Gram-negative bacteria (Escherichia coli, Salmonella enteritidis, and Pseudomonas aeruginosa) was evaluated by using of microdilution and agar diffusion assays. The results demonstrated that ultrasonic extracts (especially ethanol:water (50:50) solvent) had the higher extraction yield and antioxidant potential than maceration extracts. All extracts were effective against all tested bacteria, and Listeria monocytogenes was the most sensitive bacterium with lowest MIC value (12.5 mg/ml) and biggest diameter of growth inhibition zone (13.77 mm). Generally, this Arum maculatum leaves extracts can be suggested as an economical source of antioxidant and antimicrobial agents and can be a suitable substitute for artificial and chemical food preservatives.

Stabilizing corn oil using the lemon balm (Melissa officinalis) antioxidants extracted by subcritical water.

This research was set up to identify the impact of the antioxidant compounds present in lemon balm extract (LBE) as obtained by the subcritical water (SBCW) method on the oxidative stability of corn oil. An extraction yield of 28.52% was obtained for the SBCW and rosmarinic acid was identified to be the predominant phenolic compound present in the LBE. The total phenolic content of the LBE was found to be 212.74 mg gallic acid/g extract. Subsequently, 200, 400, 800, 1600 and 3200 ppm of the LBE were added to corn oil and its peroxide value (PV), acid value (AV), conjugated diene (CD), carbonyl value (CV), oxidative stability index (OSI), total polar compound and total phenolic compounds were compared to control and the sample containing 200 ppm of the BHA throughout the 16-day Schaal oven test at 70 °C. Our findings indicated that the corn oil containing greater LBE concentration had lower PV, AV, CD, and CV but greater OSI than the control sample. Evaluation of total polar compounds confirmed lower extent of the compounds with high polarity in the greater levels of the LBE. Finally, the LBE was able to slow down the rancidity of corn oil and the samples with higher LBE exhibited gentle oxidation rate.

Preservation of gallic acid and methyl gallate on purified Kilka fish oil oxidation by Rancimat.

Kinetic analysis of gallic acid and methyl gallate in purified Kilka oil was studied in the concentration, range 200-1600 ppm, during autooxidation in Rancimat test at 60°C. The stabilization factor (F), the oxidation rate ratio (ORR), the activity (A), and the mean rate of antioxidant consumption (Winh) were determined. The scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals decreased in the order gallic acid > methyl gallate > α-tocopherol > BHT as observed in Kilka oil. There were no significant differences between the effectiveness and strength and activity of gallic acid and methyl gallate at concentrations 200, 400, and 800 ppm. However, above 800 ppm, the activity of methyl gallate became higher than gallic acid, because methyl gallate despite gallic acid did not participate in any chain propagation reactions.

Flow behavior, viscoelastic, textural and foaming characterization of whipped cream: Influence of Lallemantia royleana seed, Salvia macrosiphon seed and carrageenan gums.

The effects of sage (Salvia macrosiphon) seed gum (SSG), balangu (Lallemantia royleana) seed gum (BSG) and carrageenan gum were examined on the foaming qualities (foam stability, foam capacity and overrun), viscoelastic properties (frequency sweep test and extrusion test) and flow properties of thickened cream as a function of gum concentration. The flow behavior of the cream samples was fitted to the Herschel-Bulkley model (R2 > 0.95). All samples demonstrated a gel structure with higher G' (storage modulus) values than the G″ (loss modulus) values. The SSG (at 0.3% concentration) was most effective on viscoelastic properties. Cream samples with 0.1 BSG exhibited foaming properties and a flow behavior similar to the full-fat control sample, i.e. there were no significant differences in either flow (τ0, n, η10) or foaming properties (overrun and foam stability). Results suggest that the formation of a thickened cream (with 30% fat) can acquire properties similar to double cream (55%) when nontraditional gums are added.

An electrochemical biosensor based on hemoglobin-oligonucleotides-modified electrode for detection of acrylamide in potato fries.

Acrylamide a neurotoxin and strong carcinogen, is found in various thermally processed foods. In this study, an electrochemical sensor for detection of acrylamide using double stranded DNA (dsDNA)/Hemoglobin (Hb)-modified screen printed gold electrode (SPGE) was designed. The immobilization of ssDNA1-SH on the surface of SPGE was confirmed by cyclic voltammetry, and the interaction between ssDNA2-NH2 and Hb with the ratio 1:1 was characterized by agarose gel. The excellent response of the designed biosensor towards acrylamide due to acrylamide and Hb adducts and change of reduction/oxidation process of Hb-Fe(III)/Hb-Fe(II) was determined by square wave voltammetry (SWV). The biosensor showed the optimum response at pH 8.0. The linear working range for acrylamide was from 2.0 × 10-6 to 5.0 × 10-2 M with a detection limit of 1.58 × 10-7 M. The biosensor was suitable for direct determination of acrylamide in water extracted of potato fries and displayed good reproductivity and high stability.

Evaluation of antioxidant properties of lemon verbena (Lippia citriodora) essential oil and its capacity in sunflower oil stabilization during storage time.

In this study, lemon verbena essential oil as a natural antioxidant was used to increase the stability of sunflower oil, and stabilization effects in terms of storage conditions were compared with synthetic antioxidant (BHT). For this purpose, the antioxidant activity of the essential oil was determined by DPPH assay and ß-carotene bleaching method. Then, lemon verbena essential oil (0, 400, 800, and 1,600 ppm) was added to sunflower oil without synthetic antioxidant and stored at 60°C for 60 days. Results from different parameters (peroxide value, free fatty acid, iodine value, total polar compound, carbonyl value, conjugated dienes, and oxidative stability index) were in agreement with each other, suggesting that lemon verbena essential oil (1,600 ppm) could act better than BHT in inhibition of lipid oxidation in sunflower oil and can be used as predominant alternative of synthetic antioxidants.

Oxidative stability of canola oil by Biarum bovei bioactive components during storage at ambient temperature.

In this study, antioxidative activities of aqueous extract of Biarum bovei (BBE) in stabilizing of canola oil during storage at 20°C was evaluated. For this purpose, the total phenolic (TP), flavonoids (TFC), and tocopherol content (TTC) of the extract were determined and ß-carotene bleaching system was used to assess the antioxidant efficacy of BBE. The amount of TP, TFC, and TTC in BBE indicated high antioxidant activity. So, different concentrations (0, 200, 800, and 1400 ppm) of BBE and butylatedhydroxyanisole (BHA; 100 ppm), were added to canola oil for 60 days at 20°C. Peroxide value (PV), carbonyl value (CV), Total polar compounds (TPC), acid value (AV), iodine values (IV), and conjugated dienes (CD) were employed to evaluate the BBE effect on canola oil stabilizing. Results indicated that 1,400 ppm of BBE exhibited stronger antioxidant activity in canola oil than BHA.

Effects of quince seed, almond, and tragacanth gum coating on the banana slices properties during the process of hot air drying.

Due to early deterioration of banana in drying process, almond, quince seed, and tragacanth gums as edible coatings were determined. For this purpose, banana slices were coated in 0.7% solution of each gum and one group remained uncoated as the control. The samples were examined at specific times considering the weight loss, color analyzing (a*, b*, and L*) through the method computer vision, color difference index, browning index, and rehydration after the samples being dried. The results showed that the weight loss of the coated samples was significantly (p < .05) higher than the uncoated samples which can be due to the alteration or destruction of the cell membrane. The almond gum-coated samples had significantly a lower ultimate browning index and quince seed gum-coated samples showed the highest rehydration. So, the gums coating is an effective way to preserve the quality characteristics of the banana slices.

Influence of Teucrium polium L. essential oil on the oxidative stability of canola oil during storage.

The susceptibility of Teucrium polium essential oil (EO) as an antioxidant for canola oil was studied. Major compounds of the EO were 11-acetoxyeudesman-4-α-ol (26.3%) and α-bisabolol (24.6%). Different concentrations (200, 600 and 1200 ppm) of EO and synthetic antioxidant BHA (200 ppm) were added to canola oil and incubated for 60 days at room temperature. Acid value (AV), peroxide value (PV), carbonyl value (CV), iodine value (IV), total phenolics (TP), total polar compounds (TPC) and oxidative stability index (OSI) of canola oil were determined. Antioxidant capacity of the EO was measured by DPPH and ß-carotene-linoleic acid assays. Results exhibited that DPPH and ß-carotene-linoleic acid experiment detections on the EO were analogous in high concentrations to those detected on BHA. Moreover, incorporated EO samples had better AV, PV, CV, IV, TP and TPC than control. EO at concentration of 600 ppm indicated higher antioxidant activity in canola oil compared with BHA.