Characterization of chitosan/Persian gum nanoparticles for encapsulation of Nigella sativa extract as an antiviral agent against avian coronavirus.

The aim of this study was to investigate the physicochemical characteristics of nanoparticles formed by the ionic gelation method between chitosan and water-soluble fraction of Persian gum (WPG) for encapsulation of Nigella sativa extract (NSE) as an antiviral agent. Our findings revealed that the particle size, polydispersity index (PDI), and zeta potential of the particles were in the range of 316.7-476.6 nm, 0.259-0.466, and 37.0-58.1 mV, respectively. The amounts of chitosan and WPG as the wall material and the NSE as the core had a considerable impact on the nanoparticle properties. The proper samples were detected at 1:1 chitosan:WPG mixing ratio (MR) and NSE concentration of 6.25 mg/mL. Fourier-transformed infrared (FTIR) spectroscopy proved the interactions between the two biopolymers. The effect of NSE on infectious bronchitis virus (IBV) known as avian coronavirus, was performed by the in-ovo method determining remarkable antiviral activity of NSE (25 mg/mL) and its enhancement through encapsulation in the nanoparticles. These nanoparticles containing NSE could have a promising capability for application in both poultry industry and human medicine as an antiviral product.

Health Risk Assessment of Lead, Cadmium, and Arsenic in Leafy Vegetables in Tehran, Iran: the Concentration Data Study.

Absorption of heavy and toxic metals causes their accumulation in the edible parts of vegetables. Pollutants such as heavy metals have directly affected the health of society and contributed to emerging diseases in recent years. The current study aimed to detect heavy metals (Pb, Cd, As) in highly consumed leafy vegetables provided from the Tehran market. Four types of vegetables, including dill, parsley, cress, and coriander were selected and 64 samples were randomly collected from fruit and vegetable markets in different regions of Tehran in August and September 2022. Then, samples were analyzed by the ICP-OES system, and health risk assessment was conducted using non-carcinogenic and carcinogenic approach. The range of Pb concentration was 54-314, < LOQ-289, < LOQ-230, and < LOQ-183 µg/kg for dill, cress, parsley, and coriander, respectively. The high mean concentrations of Pb belong to the dill (161.43 ± 77.3 µg/kg) and cress (154.75 ± 72.9 µg/kg). In some samples of dill (37.5% of samples), cress (18.75% of samples), and parsley (12.5% of samples), the Pb content was above the national allowable limit (200 µg/kg). The range of Cd concentration was < LOQ-42, < LOQ-41, < LOQ-30, and < LOQ-38 µg/kg for dill, cress, parsley, and coriander, respectively. In none of the samples, the concentration of Cd was higher than the Iranian national limit (50 µg/kg). The As occurrence was observed in all cress samples with a mean of 165.19 ± 64.83 µg/kg. The range of As concentration was < LOQ-71, < LOQ-256, 58-273, and < LOQ-75 µg/kg for parsley, dill, cress, and coriander, respectively. The THQ and HI values were higher than 1, and either ILCR value was higher than 10-4 for all tested heavy metals, it can be concluded that higher levels of heavy metals than the standard limits in some samples may raise the warning alarm and should come to the attention of the authorities.

Synthesis and characterization of novel Spirulina protein isolate (SPI)-based hydrogels through dual-crosslinking with genipin/Zn2.

Spirulina protein isolate (SPI) is a bio-polymer that can be used in the design and synthesis of hydrogels due to its biodegradability and non-toxicity. Herein, dual-crosslinked hydrogels were synthesized based on spirulina protein isolate through covalent crosslinking with genipin and metal coordination with Zn2+, and used as delivery systems. From the analysis of colorimetric indices, a high correlation between color changes and the reaction of cross-linkers with amine group structure was observed. By increasing genipin concentration in the range of 5-15 mM, the degree of cross-linking increased up to 83 %. Cross-linked hydrogels, depending on the type and concentration of cross-linkers, had a smooth to rough and dense structure with low porosity. In the FTIR spectra, significant shifts were observed in amide bonds, which are related to the formation of secondary amides after genipin crosslinking. The maximum water absorption capacity (381 %) was obtained at pH 7.4, which was significantly reduced by increasing the concentration of cross-linkers or decreasing the pH of the environment. The release rate of vitamin B6 (model) at pH 2 (45 %) was much lower than at pH 7.4 (65 %) which makes hydrogels suitable for intestinal delivery. Vitamin B6 release data indicated the best fit to the Peppas-Sahlin model in all the cases (98-99 %) and showed that the release process occurs through quasi-Fickian diffusion. The finding reveals that spirulina protein-based hydrogels can potentially be used in the design of practical carriers for the targeted delivery of bioactive compounds.

Development of curcumin-loaded Prunus armeniaca gum nanoparticles: Synthesis, characterization, control release behavior, and evaluation of anticancer and antimicrobial properties.

The present work was conducted to develop a new polysaccharide-based encapsulation system via electrostatic interactions between Prunus armeniaca gum exudates (PAGE) and Ca2+ ions to enhance the biological activity and bioavailability of curcumin. The effects of different levels of pH (6, 7, and 8) and ion concentrations (1, 3, and 5) on the particle diameter and surface charge of the samples were examined. The encapsulation efficiency in the PAGE-based nanoparticles was realized to be 86.1%, indicating the encapsulation technique applied in this study was effective to entrap most of the curcumin within the PAGE matrix. The nanoparticles showed a smooth surface with spherical shape. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (X-ray) studies confirmed the formation of polyelectrolyte complexation. The cumulative release of curcumin in simulated gastrointestinal tract was less than 75%, revealing a gradual release trend. Both pure curcumin and curcumin-loaded nanoparticles were toxic to the cancer cell lines.

pH-sensitive soluble soybean polysaccharide/SiO2 incorporated with curcumin for intelligent packaging applications.

In the present work, the effect of various concentrations of SiO2 nanoparticles (5, 10, and 15%) on physicochemical and antimicrobial properties of soluble soybean polysaccharide (SSPS)-based film was investigated. Then, the migration of SiO2 nanoparticles to ethanol as a food simulant was evaluated. Subsequently, curcumin was added to the nanocomposite formulation to sense the pH changes. Finally, the cytotoxicity of the developed packaging system was investigated. With increasing nanoparticle concentration, the film thickness, water solubility, and water vapor permeability decreased and mechanical performance of the films improved. SSPS/SiO2 nanocomposite did not show antibacterial activity. SEM analysis showed that SiO2 nanoparticles are uniformly distributed in the SSPS matrix; however, some outstanding spots can be observed in the matrix. A very homogeneous surface was observed for neat SSPS film with R a and R q values of 3.48 and 4.26, respectively. With the incorporation of SiO2 (15%) into SSPS film, R a and R q values increased to 5.67 and 5.98, respectively. Small amount of SiO2 nanoparticles was released in food simulant. The nanocomposite incorporated with curcumin showed good physical properties and antibacterial activity. A strong positive correlation was observed between TVBN content of shrimp and a* values of the films during storage time (Pearson's correlation = 0.985).

Opuntia ficus indica fruit gum: Extraction, characterization, antioxidant activity and functional properties.

A high molecular weight biopolymer was extracted from the fruits Opuntia ficus indica and characterized regarding physicochemical and rheological properties. Total carbohydrate, ash and moisture content of the polysaccharide extracted from the fruits of Opuntia ficus indica (OFIFG) were 88.85 ± 5.2%, 9.00 ± 1.30%, and 7.65 ± 0.74%, respectively. OFIFG had glucose (78.0%), arabinose (12.9%), xylose (4.8%), galactose (2.4%), and mannose (2.4%), suggesting an arabinoglucan structure. Weight average molecular weight of OFIFG was to be 3.67 × 106 g/mol. The intrinsic viscosity of OFIFG was 0.37 dL/g in deionized water at 25 °C. Steady shear measurement demonstrated that OFIFG is a shear thinning fluid. At low frequency, the gum solution exhibited a concentrated behavior. The anti-DPPH radicals activity of the gum sample was comparable to that of BHT and more than the data cited for other natural polymers. It can be found that OFIFG can be used as thickener, stabilizer and antioxidant agent in food and pharmaceutical systems.

Extraction, characterization and rheological study of the purified polysaccharide from Lallemantia ibrica seeds.

Polysaccharides are broadly used as plasticizing, emulsifying, stabilizing, thickening, gelling, binding and coating agents. The optimum extraction point based on highest yield and total carbohydrate content and lowest amount of protein was extraction temperature of 68.75 °C, pH = 10 and water to seed ratio of 36:1. Lallemantia ibrica seed gum (LISG) is a high molecular weight polysaccharide (5.74 × 106 g/mol) containing, on average, 89.60% carbohydrate, 2.98% protein, 8.95% ash, 0.2% fat and 6.52% moisture. FTIR and 1H NMR analysis revealed the presence of galactose, mannose, rhamnose, uronic acid and O-acetyl functional groups. The intrinsic viscosity of LISG (at 25 °C) was estimated to be 1.96 dL/g. The gum solutions had a shear-thinning behavior at all tested concentrations, and the Power-law model satisfactory described their rheological behavior. It was found that deionized water (pH = 7 at 25 °C) is a good solvent for LISG macromolecules. The shear thinning behavior of LISG and its high viscosity at low concentration make it a good stabilizer and thickener in the food industry.

Extraction, chemical composition, rheological behavior, antioxidant activity and functional properties of Cordia myxa mucilage.

This paper aims to investigate chemical composition, rheological behavior, antioxidant activity and functional properties of Cordia myxa mucilage (CMM). Response surface methodology (RSM) demonstrated that optimum conditions for CMM extraction were as follow: ultrasound power of 99.37 W, extraction temperature of 88.05 °C and solid to water ratio of 16.25 w/w. CMM had, on average, 77.51% carbohydrate, 5.86% total ash, 8.90% protein, 6.90% moisture, and 1.00% fat. Due to a high level of nutrients, CMM can be suggested as a value added by-product in food and pharmaceutical systems. CMM is a low molecular weight polysaccharide containing three fractions with various molecular weights. FT-IR spectrum illustrated that this polymer had all typical bands and peaks characteristics of polysaccharides. Based on steady shear measurements, CMM can be introduced as a new source of hydrocolloid with high-temperature stability. CMM had the desirable antiradical capacity, water solubility and water/oil holding capacity.

A novel inverse numerical modeling method for the estimation of water and salt mass transfer coefficients during ultrasonic assisted-osmotic dehydration of cucumber cubes.

The objective of this paper was to study the moisture and salt diffusivity during ultrasonic assisted-osmotic dehydration of cucumbers. Experimental measurements of moisture and salt concentration versus time were carried out and an inverse numerical method was performed by coupling a CFD package (OpenFOAM) with a parameter estimation software (DAKOTA) to determine mass transfer coefficients. A good agreement between experimental and numerical results was observed. Mass transfer coefficients were from 3.5 × 10-9 to 7 × 10-9 m/s for water and from 4.8 × 10-9 m/s to 7.4 × 10-9 m/s for salt at different conditions (diffusion coefficients of around 3.5 × 10-12-11.5 × 10-12 m2/s for water and 5 × 10-12 m/s-12 × 10-12 m2/s for salt). Ultrasound irradiation could increase the mass transfer coefficient. The values obtained by this method were closer to the actual data. The inverse simulation method can be an accurate technique to study the mass transfer phenomena during food processing.

Dilute solution properties of Prunus armeniaca gum exudates: Influence of temperature, salt, and sugar.

The aim of the current paper was to investigate the effect of different temperatures, salts and sugars on dilute solution properties of Prunus armeniaca gum exudates (PAGE) as a starting point to evaluate the potential utilization of this novel source of hydrocolloids in food and pharmaceutical systems. Berry number and the slope of master curve indicated that PAGE samples in all evaluated conditions were in dilute domain without coil overlapping and entanglement. Furthermore, the slope power law model also demonstrated that the molecular conformation of PAGE in all tested temperatures was close to rode-like. On the other hand, PAGE samples had random coil conformation in the presence of sugars and ions studied. Activation energy and chain flexibility of PAGE were found to be 0.83×107 (J/kg) and 997.3, respectively. This result revealed that temperature has a slight effect on intrinsic viscosity of PAGE solution, implying this gum can be introduced as a promising ingredient in food formulation that need to high stability against temperature. The data obtained in the present study and results thereof can be useful when considering the effect of additives generally used in food products and/or processing parameters like temperature in food systems.

Some physico-chemical properties of Prunus armeniaca L. gum exudates.

The objectives of this paper were to investigate some physicochemical properties of Prunus armeniaca L. gum exudates (PAGE). PAGE had, on average, 66.89% carbohydrate, 10.47% uronic acids, 6.9% moisture (w.b.), 2.91% protein, 4% ash and 1.59% fat. PAGE was composed of monosaccharides including l-arabinose, d-galactose, xylose, mannose and rhamnose in molar percentages of 41.52%, 23.72%, 17.82%, 14.40% and 2.54%, respectively. Elemental analysis showed that PAGE had high values of nutrients. FTIR analysis demonstrated the presence of carboxyl, hydroxyl and methyl groups and glycoside bonds. The weight average molecular weight, number average molecular weight and polydispersity index were found to be approximately 5.69 × 10(5)g/mol, 4.33 g/mol and 1.31, respectively. Rheological measurement of PAGE solutions as a function of concentration (8, 10 and 12% (w/w)) and temperature (10, 20, 30 and 40°C) demonstrated that the gum solutions had a non Newtonian shear thinning behaviour. Intrinsic viscosity for PAGE in deionized water was 3.438 dl/g based on Kramer equation.

Evaluation of Homocysteine Level as a Risk Factor among Patients with Ischemic Stroke and Its Subtypes.

BACKGROUND: Epidemiological research has shown that increased total homocysteine (tHcy) levels are associated with an increased risk of thromboembolic disease; however, controversy still exists over which subtype of stroke is allied to hyperhomocysteinemia. This study aimed to investigate whether elevated tHcy is an independent risk factor for ischemic stroke and to compare tHcy levels in patients with ischemic stroke subtypes. METHODS: We performed a case-control study, in which 171 ischemic stroke patients aged over 16 years and 86 age and sex-matched controls were eligible to participate and were enrolled from January 2009 to January 2010. The patients' demographic data, traditional stroke risk factors, and the results of fasting tHcy, vitamin B12, and folate of serum were collected in the first 5 days after ischemic stroke. Stroke subtypes were classified according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria. SPSS software (version 13) was used for the statistical analysis of the data, and a P value smaller than 0.05 was considered statistically significant. RESULTS: The mean fasting Hcy levels was significantly higher in the cases (16.2 µmol/L, 95% CI: 14.8 to 17.5) than in the controls (13.5 µmol/L, 95% CI: 12.4 to 14.6) (P=0.013). The mean Hcy levels was elevated significantly in those with cardioembolic strokes compared with the controls (17.7 µmol/L, 95% CI: 14.8 to 20.5; P=0.010). The plasma Hcy level was associated with an adjusted odds ratio of 2.17 (95% CI: 1.24 to 3.79; P=0.004) for Hcy above 15 µmol/L concentration for all types of stroke. CONCLUSION: Our data showed that elevated serum Hcy is an independent risk factor for ischemic stroke and it has a strong association with cardioembolic subtype.