Development and characterization of nanostructured pharmacosomal mesophases: An innovative delivery system for bioactive peptides

Purpose: To potentially enhance the bioavailability and extend the bioactivity effectiveness of Isoleucine-Proline-Proline (IPP, an antihypertensive bioactive peptide of dairy origin), a novel Lyotropic Liquid Crystalline Pharmacosomal Nanoparticle (LLCPNP) was synthesized, and its physicochemical and technological characteristics were studied. Methods: LLCPNPs precursors were developed using IPP and soy phosphatidylcholine via complex formation. Polarized light microscopy, small angle X-ray scattering, differential scanning calorimetry, dynamic light scattering and Fourier transform infrared spectroscopy were employed to characterize the physicochemical properties of the nanoparticles. The in-vitro release and its related mechanisms were also studied. Results: Fourier transform infrared spectroscopy confirmed the complexation between the components of LLCPNPs. Phase behavior evaluation by polarized light microscope showed the characteristic birefringent texture. These findings along with those of small angle X-ray scattering and differential scanning calorimetry proved the formation of lamellar LLCPNPs. These particles represented nanometric size (<100 nm), high incorporation efficiency (93.72%) and proper physicochemical stability during long-term storage. In-vitro studies demonstrated a sustained release behavior fitted to non-Fickian diffusion and Higuchi kinetic models. Conclusion: The present study results emphasized that LLCPNPs could be proposed as an unrivaled carrier to promote the bioavailability, stability and shelf-life of nutraceutical and biopharmaceutical formulations containing bioactive peptides

Properties of Dried Apricots Pretreated by Ultrasound-Assisted Osmotic Dehydration and Application of Active Coatings

Research background. The worldwide demand for healthy and sulphur-free dried vegetables and fruits has grown. Combined ultrasound-assisted osmotic dehydration (UOD) and application of active coatings incorporating natural preservatives represents an attractive alternative for sulphuring process to preserve the sensorial and nutritional quality of dried fruits. The aim of this study was to investigate the effect of osmotic dehydration (OD) and UOD and the use of pectin coatings (alone or with citric acid, CA or ascorbic acid, AA) on physical, textural and microstructural properties of hot air-dried apricot. Experimental approach. Fresh apricot cubes (1 cm3) were pre-treated with either OD at a temperature of 55 °C for 30 and 45 min or UOD at two ultrasonic frequencies of 25 and 35 kHz for 30 and 45 min followed by application of active coatings with pectin alone, pectin + CA or pectin + AA for 10 min. All pre-treated coated samples were then hot-air dried at a temperature of 60 °C until a final moisture content of 20 % (wet basis) was reached. Physical (shrinkage, apparent and bulk densities), chemical (browning value, water activity), textural (firmness and shrinkage), microstructure and microbial load of dried apricot was studied. Results and conclusions. Application of OD and UOD improved physical and textural properties of the dried apricots. Moreover, apparent and bulk densities, rehydration capacity of OD and UOD pre-treated samples were increased. While, shrinkage, water activity and microbial load were decreased. Firmness of UOD pre-treated samples was significantly (p < 0.05) lower than that of OD ones. Likewise, increasing ultrasound frequency from 25 to 35 kHz led to a significant decrease in Fmax values of dried apricots. Furthermore, coating of the OD and UOD processed samples with pectin + CA increased Fmax and decreased rehydration capacity of dried apricots. Scanning electron microscopy of both OD and UOD samples illustrated improvement of textural properties. The utilization of both OD pre-treatment and pectin edible coatings resulted in a decrease in browning values. However, UOD increased browning values of the dried apricots. Coating of UOD samples with pectin + AA resulted in substantial discoloration in hot air-dried apricot. Novelty and scientific contribution. This study advances the knowledge in the field of fruit drying by combined application of OD or UOD pre-treatments with post-treatments with active edible coatings on different properties of hot-air dried apricot

Physicochemical, thermal and rheological properties of pectin extracted from sugar beet pulp using subcritical water extraction process

The objective of this study was to characterize the properties of pectin extracted from sugar beet pulp using subcritical water (SWE) as compared to conventional extraction (CE). The research involved advanced modeling using response surface methodology and optimization of operational parameters. The optimal conditions for maximum yield of pectin for SWE and CE methods were determined by the central composite design. The optimum conditions of CE were the temperature of 90 °C, time of 240 min, pH of 1, and pectin recovery yield of 20.8%. The optimal SWE conditions were liquid-to-solid (L/S) ratio of 30% (v/w) at temperature of 130 °C for 20 min, which resulted in a comparable yield of 20.7%. The effect of obtained pectins on viscoamylograph pasting and DSC thermal parameters of corn starch was evaluated. The contents of galacturonic acid, degree of methylation, acetylation, and ferulic acid content were higher in the pectin extracted by SWE, while the molecular weight was lower. Similar chemical groups were characterized by FTIR in both SWE and CE pectins. Color attributes of both pectins were similar. Solutions of pectins at lower concentrations displayed nearly Newtonian behavior. The addition of both pectins to corn starch decreased pasting and DSC gelatinization parameters, but increased ΔH. The results offered a promising scalable approach to convert the beet waste to pectin as a value-added product using SWE with improved pectin properties.Axencia Galega de Innovación | Ref. IN607A2019 / 0

Adsorption of crystal violet dye using activated carbon of lemon wood and activated carbon/Fe3O4 magnetic nanocomposite from aqueous solutions: a kinetic, equilibrium and thermodynamic study

Activated carbon prepared from lemon (Citrus limon) wood (ACL) and ACL/Fe3O4 magnetic nanocomposite were effectively used to remove the cationic dye of crystal violet (CV) from aqueous solutions. The results showed that Fe3O4 nanoparticles were successfully placed in the structure of ACL and the produced nanocomposites showed superior magnetic properties. It was found that pH was the most effective parameter in the CV dye adsorption and pH of 9 gave the maximum adsorption efficiency of 93.5% and 98.3% for ACL and ACL/Fe3O4, respectively. The Dubinin–Radushkevich (D-R) and Langmuir models were selected to investigate the CV dye adsorption equilibrium behavior for ACL and ACL/Fe3O4, respectively. A maximum adsorption capacity of 23.6 and 35.3 mg/g was obtained for ACL and ACL/Fe3O4, respectively indicating superior adsorption capacity of Fe3O4 nanoparticles. The kinetic data of the adsorption process followed the pseudo-second order (PSO) kinetic model, indicating that chemical mechanisms may have an effect on the CV dye adsorption. The negative values obtained for Gibb’s free energy parameter (−20 < ΔG < 0 kJ/mol) showed that the adsorption process using both types of the adsorbents was physical. Moreover, the CV dye adsorption enthalpy (ΔH) values of −45.4 for ACL and −56.9 kJ/mol for ACL/Fe3O4 were obtained indicating that the adsorption process was exothermic. Overall, ACL and ACL/Fe3O4 magnetic nanocomposites provide a novel and effective type of adsorbents to remove CV dye from the aqueous solutions

Physical, mechanical, and antibacterial characteristics of bio-nanocomposite films loaded with Ag-modified SiO2 and TiO2 nanoparticles

In this study, starch-based films incorporating metal oxide (MO2) nanoparticles (NPs) of TiO2 and SiO2 (at a concentration of 1 to 4 wt. %) were produced by solution casting method. In order to exhibit antimicrobial properties, MO2 NPs were modified by synthesizing silver (Ag) ions over the NPs using cationic adsorption method. Ag ions were then reduced to metallic Ag by sodium borohydride solution. Scanning electron microscopy showed a smooth surface for the pure starch film. Incorporating MO2@Ag NPs in the films increased surface roughness with agglomerated NPs within starch matrix. Energy dispersive X-ray analysis exhibited a uniform dispersion of Ag-loaded MO2 NPs, which increases surface contact between these NPs and the biopolymer matrix leading to improved physical and mechanical properties of the resulting films. With increasing in the NPs concentrations, the tensile strength and elongation at break % of the films increased and decreased, respectively. Incorporating MO2@Ag NPs into starch matrix decreased solubility in water and water vapor permeability of the obtained films, and significantly inhibited the growth of Escherichia coli and Staphylococcus aureus. The most antibacterial effect was obtained for the films containing higher weight concentrations of Ag-loaded SiO2-NPs

Decoration of Citrus limon wood carbon with Fe3O4 to enhanced Cd2+ removal: A reclaimable and magnetic nanocomposite

In the present study, the activated carbon of lemon (ACL) was generated from Citrus limon wood waste and composited with Fe3O4 nanoparticles. The ACL/Fe3O4 magnetic composite was effectively used to eliminate Cd2+ from an aqueous solution. The active surface area values for ACL and ACL/Fe3O4 magnetic composite were 25.99 m2/g and 38.70 m2/g, respectively indicating the effectiveness of Fe3O4 nanoparticles in improving ACL active surface area. The response surface methodology with central composite design (RSM-CCD) was used to determine optimal values of pH, ACL/Fe3O4 dose, contact time, and Cd2+ concentration on the decontamination efficiency. The Langmuir and Freundlich isotherm models had more potential to describe the adsorption process using ACL and ACL/Fe3O4, respectively. The Langmuir-based adsorption capacity was obtained as 28.2 mg/g (ACL) and 39.6 mg/g (ACL/Fe3O4). A pseudo-second order (PSO) model was successfully applied to evaluate the adsorption process kinetic behavior. A higher value of α parameter for ACL/Fe3O4 (5.7 mg/g.min) than that of ACL (3.5 mg/g.min) indicated that the magnetic composite had a greater tendency to absorb Cd2+. In addition, the Weber–Morris model showed that various mechanisms such as intraparticle diffusion and boundary layer effects may have a role in the adsorption process. The study of ad(de)sorption behavior showed that the adsorbents have a good ability to adsorb Cd2+ and no significant change in their performance has been made up to 4 times of reuse. Our results showed that ACL modification using Fe3O4 nanoparticles improved the adsorption efficiency of ACL to remove Cd2+ from the aqueous solutions. © 2021 Elsevier Lt

Cadmium ion removal from aqueous media using banana peel biochar/Fe3O4/ZIF-67

In the present study, banana peel waste was used as a suitable source for biochar production. The banana peel biochar (BPB) was modified using Fe3O4 magnetic and ZIF-67 nanoparticles. The modification of the BPB surface (4.70 m2/g) with Fe3O4 and Fe3O4/ZIF-67 significantly increased the specific surface of the nanocomposites (BPB/Fe3O4: 78.83 m2/g, and BPB/Fe3O4/ZIF-67: 1212.40 m2/g). The effect of pH, temperature, contact time, adsorbent dose, and concentration of Cd2+ on the efficiency of the Cd2+ adsorption was explored. Maximum adsorption efficiencies for BPB (97.76%), BPB/Fe3O4 (97.52%), and BPB/Fe3O4/ZIF-67 (99.14%) were obtained at pH 6, Cd2+ concentration of 10 mg/L, times of 80 min, 50 min, and 40 min, and adsorbent doses of 2 g/L, 1.5 g/L, and 1 g/L, respectively. Thermodynamic measurements indicated that the process is spontaneous and exothermic. The maximum capacity of Cd2+ adsorption using BPB, BPB/Fe3O4, and BPB/Fe3O4/ZIF-67 were obtained 20.63 mg/g, 30.33 mg/g, and 50.78 mg/g, respectively. The Cd2+ adsorption using magnetic nanocomposites followed the pseudo-first-order kinetic model. The results showed that studied adsorbents especially BPB/Fe3O4/ZIF-67 have a good ability to adsorb-desorb Cd2+ and clean an effluent containing pollutants

Development of new magnetic adsorbent of walnut shell ash/starch/Fe3O4 for effective copper ions removal: Treatment of groundwater samples

The goal of this investigation was to develop a new magnetic nanocomposite of walnut shell ash (WSA)/starch/Fe3O4 to remove Cu (II) present in groundwater samples. The desired nanocomposites were successfully synthesized by the chemical deposition method. The specific active surface area for pristine WSA and WSA/starch/Fe3O4 magnetic nanocomposites was determined to be 8.1 and 52.6 m2/g, respectively. A central composite design for the response surface method was utilized to study the influence of pH, adsorbent quantity, initial content of Cu (II), temperature, and contact time. This method showed the success of the model to design process variables and to estimate the appropriate response. The P- and F-value determined for the quadratic polynomial model showed the significance and accuracy of the proposed model in examining experimental and predicted data with R2 and Adj.R2 of 0.994 and 0.991, respectively. The Cu adsorption onto WSA and WSA/starch/Fe3O4 obeyed the Freundlich and Langmuir models, respectively. The highest Cu (II) sorption capacity of 29.0 and 45.4 mg/g was attained for WSA and WSA/starch/Fe3O4, respectively. The free energy of Gibbs had a negative value at 25–45 °C indicating that the adsorption process is spontaneous. Also, negative ΔH values for copper adsorption showed that the processes are exothermic. The kinetic adsorption data for WSA and WSA/starch/Fe3O4 followed the pseudo-second order (PSO) model. The ability of the composite adsorbent to remove copper from three groundwater samples showed that it could be reused at least 3 times with appropriate efficiency, depending on the water quality

Generation of biodiesel from edible waste oil using ZIF-67-KOH modified Luffa cylindrica biomass catalyst

To produce biodiesel from edible waste oil, a new heterogeneous catalyst based on Luffa cylindrica biomass was used. For this purpose, first, Luffa cylindrica carbon was modified using zeolite imidazole metal-organic framework (ZIF-67) and KOH and used in the biodiesel production. Fourier-transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-ray Powder Diffraction (XRD), Brunauer–Emmett–Teller (BET), Transmission Electron Microscopy (TEM), Raman, and Thermogravimetric Analysis (TGA) techniques were used to investigate the properties of the synthesized catalyst. BET values for activated carbon of Luffa cylindrica (ACL), ZIF-67, ACL/ZIF-67, and ACL/ZIF-67/KOH samples were determined to be 99.714, 1695.7, 956.99, and 2.322 m2/g, respectively, indicating that modification of biomass using ZIF-67 improved its specific active surface, which can retain more KOH in the pores of catalyst. To evaluate the ability of the synthesized catalyst, the effect of various parameters such as reaction time, temperature, amount of catalyst, the molar ratio of oil to methanol, and mixing speed were investigated. The results showed good catalytic activity in converting edible waste oil to biodiesel and maximum efficiency of biodiesel production (98.31%) in laboratory conditions such as a temperature of 65 °C, a catalyst concentration of 3 wt%, a reaction time 3 h, a methanol: oil ratio of 15:1 and a mixing speed of 600 rpm. After determining the optimal laboratory conditions, the study of regeneration and reuse of the catalyst showed that the catalyst had a suitable catalytic activity and can use more than 4 steps in the biodiesel production process. The properties of biodiesel obtained under optimal conditions were evaluated according to the international standards (ASTM D6751 and EN-14214). The results showed that the produced biodiesel possess suitable properties and can replace fuels derived from fossil fuels

Properties and application of multifunctional composite polypropylene-based films incorporating a combination of BHT, BHA and sorbic acid in extending donut shelf-life

To extend the shelf-life of packaged donut without the addition of preservative, polypropylene-based active composite films loaded with a combination of sorbic acid, BHA and BHT were prepared by the extrusion moulding method: T1 (Control-pure PP-film), T2 (PP-BHT1%-SA2%), T3 (PP-BHA3%-SA2%) and T4 (PP-BHT1%-BHA1%-SA2%). The incorporation of active additives enhanced water vapour permeability (WVP) and increased oxygen permeability of films. Active films had higher antioxidant activity than pure PP in the order T4 > T2 > T3 (89.11, 83.40 and 79.16%). In vitro examinations demonstrated a significant antibacterial effect on Escherichia coli and S. aureus growth. Overall migration was not significantly different for watery food simulants, while in acidic and fatty foods increased it significantly. The effect of the active films on the fried and packaged donut samples showed significantly higher moisture contents and peroxide values, while acidity was lower. T2 film is proposed due to the preservation of the intrinsic properties of the film, increasing the storage period up to 25 to 50 days