Fabrication of nanostructured mesoporous starch encapsulating soy-derived phytoestrogen (genistein) by well-tuned solvent exchange method.

The present research was concerned with preparation of mesoporous starch (MPS) as a carrier for genistein, a model of poorly water-soluble phytoestrogen isoflavone; and exploration of the impact of different fabrication parameters on structural and loading properties. MPS is considered as a highly porous biomaterial which typically possesses nanometer-sized porous microstructure and low density, providing a large effective specific surface area (SSA) and hydrophilic surface to improve solubility, stability and bioavailability of poorly water-soluble active agents. To fabricate MPS, various concentrations (8-14% w/v) of starch from different sources (corn, potato and tapioca) was used for gel formation and the successive solvent exchange process was performed with use of various ethanol concentrations (40-70% v/v), which were then dried by different techniques (rotary vacuum evaporation, microwave and freeze drying). MPS quality attributes such as SSA, total porous volume, BJH pore diameter and swelling ratio were determined and effects of the fabrication parameters were investigated using L9-Taguchi orthogonal array design. The results indicate that second order polynomial regression models were well fitted for all response variables. Interestingly, the starch components greatly influenced physical properties of MPS. Also, the drying type and ethanol concentration altered significantly the model equations. The overall best fabrication condition (14% corn starch, 100% ethanol concentration in aging step and rotary vacuum drying) resulted in favorable MPS preparation with mean size of 105.4 nm and unimodal distribution. In the next step, genistein was encapsulated in MPS microstructure at different ratios, resulting in high loading capacity and efficiency (44.71% and 79.9%, respectively) at 1:1 weight ratio. Equilibrium adsorption isotherm of genistein was evaluated also by four different kinetics models including Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin isotherms. The experimental data were found to be fitted well to the Langmuir model (R2 = 0.989). According to the electron microscopy and XRD analysis, the degree of genistein crystallinity lowered remarkably after the impregnation in to MPS, indicating improved solubility. In-vitro release profile of genistein from MPS in the simulated gastrointestinal buffer solutions (pH 1.2 and 6.8) demonstrated that incorporating genistein into the MPS enhanced the dissolution rate compared with genistein powder. Release kinetic data were fitted to the Higuchi model (R2 = 0.98), indicating diffusion-controlled release mechanism. Altogether, well-tuned MPS fabrication method can be utilized for an efficient encapsulation and dissolution enhancement of poorly soluble phytochemicals, such as genistein.

Physicochemical and functional properties of oleaster (Elaeagnus angustifolia L.) polysaccharides extracted under optimal conditions.

This research aimed to optimize the polysaccharides extraction of oleaster fruit and then to investigate the physicochemical and functional properties of extracted polysaccharides. Temperature, water to dry matter ratio, time, and alcohol ratio were considered as variables. Purity of extracted polysaccharides was considered as the response. Optimization of polysaccharides extraction from full grain oleaster showed that all variables had effects on the purity of extracted polysaccharides alone or by interacting with other variables. The results showed that the temperature, 60 °C; water to dry matter ratio, 53:1 (V/W); time, 5 h; and alcohol ratio of 2.9 (V/V) were the best conditions for achieving the highest purity in extracted polysaccharides. The extracted polysaccharides had the potential of emulsion formation with high stability; however, foamability was not observed in this polysaccharide. In addition, the solubility of polysaccharide powder was high, and it increased with an increase in temperature, which resulted in a decrease in water absorption indicating the effect of heat on the structure and the amount of water absorption of extracted polysaccharides. The results obtained from FTIR confirmed the polysaccharide nature of extracted powder, and the X-ray diffraction pattern of extracted polysaccharides showed its semi-crystalline structure.

Investigation of stability, consistency, and oil oxidation of emulsion filled gel prepared by inulin and rice bran oil using ultrasonic radiation.

Inulin, rice bran oil and rosemary essential oil were used to produce high quality emulsion filled gel (EFG) using ultrasonic radiation. Response surface methodology was used to investigate the effects of oil content, inulin content and power of ultrasound on the stability and consistency of prepared EFG. The process conditions were optimized by conducting experiments at five different levels. Second order polynomial response surface equations were developed indicating the effect of variables on EFG stability and consistency. The oil content of 18%; inulin content of 44.6%; and power of ultrasound of 256 W were found to be the optimum conditions to achieve the best EFG stability and consistency. Microstructure and rheological properties of prepared EFG were investigated. Oil oxidation as a result of using ultrasonic radiation was also investigated. The increase of oxidation products and the decrease of total phenolic compounds as well as radical scavenging activity of antioxidant compounds showed the damaging effect of ultrasound on the oil quality of EFG.

Basil seed mucilage as a new source for electrospinning: Production and physicochemical characterization.

In this study nanofibers were prepared via the electrospinning technique by basil seed mucilage (BSM) as a new source of hydrocolloid. Polyvinyl alcohol (PVA) was used as an aiding agent. Viscosity and electrical conductivity of BSM/PVA solutions of different volume ratios (100:0, 80:20, 60:40, 40:60, 20:80 and 0:100) were in the range of 790-1300cP and 745-2140µS/cm, respectively. Morphology of nanofibers were investigated using scanning electron microscopy (SEM) that showed an average diameter range of 179-390nm. Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) studies were used to analysis chemical composition, crystalline structure and thermal characteristics of nanofibers. The characteristic picks of basis seed mucilage were found in BSM/PVA nanofibers. The crystalline index of BSM, PVA and BSM/PVA nanofibers were 54, 35 and 43%, respectively. The BSM based nanofibers can be used for different applications such as bioactive encapsulation and packaging film production.

Encapsulation optimization of lemon balm antioxidants in calcium alginate hydrogels.

Calcium alginate hydrogel beads were used to encapsulate lemon balm extract. Chitosan layer was used to investigate the effect of hydrogel coating. To determine the interactions of antioxidant compounds of extract with encapsulation materials and its stability, microstructure of hydrogel beads was thoroughly monitored using scanning electron microscopy and Fourier transform infrared (FTIR). Total polyphenols content and antiradical activity of lemon balm extract were also evaluated before and after encapsulation. Three significant parameters (lemon balm extract, sodium alginate, and calcium chloride concentrations) were optimized by response surface methodology to obtain maximum encapsulation efficiency. The FTIR spectra showed no interactions between extract and polymers as there were no new band in spectra of alginate hydrogel after encapsulation of active compounds of lemon balm extract. The antioxidant activity of lemon balm extract did not change after encapsulation. Therefore, it was found that alginate is a suitable material for encapsulation of natural antioxidants. Sodium alginate solution concentration, 1.84%, lemon balm extract concentration, 0.4%, and calcium chloride concentration, 0.2% was determined to be the optimum condition to reach maximum encapsulation efficiency.

Patterns of pre-treatment drug abuse, drug treatment history and characteristics of addicts in methadone maintenance treatment in Iran.

BACKGROUND: Opiates are the main drugs of abuse, and Methadone Maintenance Treatment (MMT) is the most widely administered drug addiction treatment program in Iran. Our study aimed to investigate patterns of pre-treatment drug abuse, addiction treatment history and characteristics of patients in MMT in Tehran. METHODS: We applied a stratified cluster random sampling technique and conducted a cross-sectional survey utilizing a standard patient characteristic and addiction history form with patients (n = 810) in MMT. The Chi-square test and t-test served for statistical analyses. RESULTS: A clear majority of the participants were men (96%), more than 60% of whom were between 25 and 44 years of age, educated (89% had more than elementary education), and employed (>70%). The most commonly reported main drugs of abuse prior to MMT entry were opium (69%) and crystalline heroin (24%). The patients' lifetime drug experience included opium (92%), crystalline heroin (28%), cannabis (16%), amphetamines (15%), and other drugs (33%). Crystalline heroin abusers were younger than opium users, had begun abusing drugs earlier, and reported a shorter history of opiate addiction. CONCLUSION: Opium and crystalline heroin were the main drugs of abuse. A high rate of addiction using more dangerous opiate drugs such as crystalline heroin calls for more preventive efforts, especially among young men.