Electrohydrodynamic atomization of Balangu (Lallemantia royleana) seed gum for the fast-release of Mentha longifolia L. essential oil: characterization of nano-capsules and modeling the kinetics of release

The aim of this study is to optimize encapsulation of Mentha longifolia L. essential oil into Balangu (Lallemantia royleana) seed gum nano-capsules, to increase their utility as flavoring and bioactive agents in foods and beverages. Essential oil emulsions with Balangu seed gum (0.25 and 0.5% w/w) and various polyvinyl alcohol (PVA) concentrations (0.5, 1 and 2%) combined with Tween-20 (0.06, 0.08 and 0.1%) were electrosprayed. Increasing the concentration of PVA increased the emulsion viscosity and improved both loading capacity (77.56 to 84.68%) and encapsulation efficiency (81.54 to 87.82 %) of the essential oil within the structure of the Balangu gum nano-capsules. Field emission scanning electron microscopy (FESEM) indicated that by increasing the amount of the gum (from 0.25 to 0.5%) and PVA (from 1 to 2%), the process could be made to produce nanofibers. The Mentha longifolia L. essential oil was entrapped in nanostructures without any chemical interaction with encapsulant material, this was demonstrated by Fourier transform infrared spectroscopy and differential scanning calorimetry. The release mechanisms and kinetics of loaded Mentha longifolia L. essential oil were evaluated in different simulated food models (aqueous, acidic, alcoholic or alkalic and oily food models) and release profiles data were fitted to first order, Kopcha, Korsmeyer-Peppas, and Peppas-Sahlin models. The essential oil release profiles fitted well to the Peppas-Sahlin model for a range of simulated foods. The release mechanism of the essential oil from the nanostructure of the Balangu seed gum is mainly controlled by the Fickian diffusion phenomenon

Millifluidic-assisted ionic gelation technique for encapsulation of probiotics in double-layered polysaccharide structure

A unique double-layered vehicle was fabricated for the first time based on a millifluidic/direct gelation to encapsulate probiotics. Free probiotic bacteria are usually very sensitive to severe gastrointestinal conditions and maintaining their survival when passing through the digestive tract is essential. The effects of alginate concentration (20–30 g/L), flow rates of alginate (0.8–1.2 mL/min), and W/O emulsion (0.5–0.7 mL/min) on encapsulation efficiency (EE), size, and sphericity of core–shell millicapsules were optimized for encapsulation of Bifidobacterium animalis subsp. lactis and Lactobacillus plantarum. The optimized calcium-alginate millicapsule was spherical (0.97 ± 0.01 SF), with an average diameter of 4.49 ± 0.19 mm, and encapsulation efficiency of 98.17 ± 0.5 %. Two strains were encapsulated separately in W/O emulsion as a core of the millicapsule. After coating with chitosan, the encapsulation yield of the bacteria, survival rates under simulated gastrointestinal (GI) conditions, and viability during storage were determined. Survival efficiency of B. animalis subsp. lactis and L. plantarum after millifluidic encapsulation were found to be 92.33 and 90.81 %, respectively. Cell viability of encapsulated probiotics after passing through the GI system was improved (7.5 log CFU mL−1 for both strains). Although the viability of the encapsulated probiotics stored at −18 °C for five months significantly decreased (p<0.05), the number of live cells was approximately in accordance with the standard definition of long-term probiotic survival (6 log CFU/g). This work provides a pathway for the construction of an innovative delivery system with high efficiency and protective effects for probiotics

Efficient Removal of Pb(II) and Cr(III) Ions from Aqueous Solutions Using Modified Cellulose Nanocrystals into the Polyamide Nanofiltration Membrane

Nowadays, discharge of toxic heavy metals through industrial, domestic, and agricultural effluents into the environment, in this study, the efficiency of thin-layer nanocomposite (TFN) nanofiltration membranes made using surface polymerization in combination with modified cellulose nanoparticles (mNC) was assessed for the removal of lead and chromium ions from aqueous solutions. In so doing, after modification of MNCSNCs, fabrication of membrane substrate and also PA selective layer, and then testing the performance of the membrane, the physical properties of the modified nanoparticles and nanocomposite membranes were also investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), atomic force microscopy (AFM), and zeta potential. Based on the Results obtained, the water flux of TFN2 membranes increased from 42 to 125 l/m2/h. Also, at pH = 8.5, the removal rate of Pb(II) and Cr(III) was 93% and 100%, respectively. Moreover, under these conditions, the adsorption process followed the Langmuir adsorption isotherm and the pseudo-second-order kinetic models. In general, the results showed that the synthesized nanofiltration nanocomposite membrane by embedding modified cellulose nanocrystals can be used to effectively remove Pb(II) and Cr(III) ions from aqueous solutions

Performance Evaluation of Titanium Dioxide Nanocomposite Membrane in Removal of Lead from Aqueous Solutions

Among the methods used to remove heavy metals are membrane processes that, with less use of chemicals, are able to quickly produce high-quality penetration. In this study, a nanocomposite membrane with the ability to separate lead was used. The black titanium dioxide nanoparticle was synthesized using the pyrolysis method. Adsorption experiments were performed using a nanofiltration unit. The results of lead adsorption isotherms showed that the lead adsorption process using the membrane follows the Langmuir model with a correlation coefficient of 0.995. The results of the study of lead metal adsorption kinetics showed that the process of adsorption of lead by the adsorbent follows the quasi-second order kinetics so that the correlation coefficient of the second-order quasi-model is equal to 0.999 which is compared with the quasi-correlation coefficient. The maximum and minimum fluxes between different membranes were related to 0.1 mg/l of titanium dioxide nanoparticles in terms of time and pressure for 50 and 600 minutes and pressures of 45 and 145 bar, with increasing the initial concentration of pollutants, the percentage of adsorption decreases. This can be due to the delay in balancing the adsorbent and the contaminant

Protein-based halochromic electrospun nanosensor for monitoring Trout fish freshness

In the present study, a protein- based halochromic nanosensor was designed to assess the quality of rainbow trout fillets. Zein nanofibers containing alizarin as the indicator dye were electrospun. The sensors were characterised using SEM, FT-IR, DSC, XRD, dye leaching, response time experiments and colorimetric analysis. TVB-N, TVC and pH of fish fillets were also measured over 12 days of storage at 4°C. FT-IR results showed that the alizarin was incorporated in the zein matrix by intermolecular hydrogen bonding. DSC graphs of zein based samples showed that the temperature of dehydration, glass transition and protein unfolding in the halochromic nanofibers were lower than in powdered zein. The amorphous structure of the zein samples was confirmed by XRD analysis. No color changes were occurred in the first 4 days of storage, but later, a light purple color could be observed in the sensor by the naked eye. The color of sensor became magenta by the 10th and 12th day of cold storage indicating spoilage. This fabricated halochromic nanosensor can monitor fish freshness in real time through color changes. The colorimetric results correlated well with microbial and chemical changes in the fish

Designing a colorimetric nanosensor based on dithizone and cholesteric liquid crystals loaded in electrospun cellulose acetate nanofibers: Monitoring the quality of pistachio as a case study

We describe colorimetric electrospun nanosensors designed to work at temperatures of 35–36�C. The mode of operations is based on a combination of the ability of dithizone to exhibit appropriate color and cholesteric liquid crystals presenting a wide range of melting points at various mixing ratios. To this end, different levels of dithizone (IUPAC name 1-anilino-3-phenyliminothiourea), different ratios of cholesteric liquid crystals to cellulose acetate and cholesteryl oleyl carbonate to cholesteryl nanoate were defined as independent variables and the total color difference was considered as the response in the response surface methodology approach. The results showed that the range of color palette changes of the designed samples was diverse and could be applied to different products. As a case study, the applicability of the sensor was evaluated on the 4-month shelf life of pistachio nuts at 35�C whilst the spoilage criteria were reconciled with the color changes in the designed senso