فهرست مطالب mohammad hassan eikani

The application of carriers is a proper means of improving the transfer and increasing the bioavailability of bioactive compounds. α-lactalbumin is the second major component of whey protein nutritionally consisted of Trp, Lys and Cys residues which can be employed as nutraceutical carriers. Oleuropein is a bioactive compound with pharmaceutical and antioxidant properties which is found abundantly in olive leaves and at lower levels in olive oil. The current study was undertaken to explore the interaction of α-lactalbumin-oleuropein complex at 25, 50 and 72 ˚C at pH 7 by using fluorescent, UV and circular dichroism spectroscopy techniques together with molecular docking. The results from UV and fluorescent studies demonstrate that site and binding constant are increased as the temperature increased due to the change in conformation and rearrangement of protein structure. Moreover, circular dichroism results depicted that α-helix and β-sheet structures are decreased and increased respectively as a result of temperature increase up to 72 ˚C. Ultimately, the molecular docking findings revealed that the best binding energy for complex formation was about -6.3 kCal/mol and the best binding site was between the α-helix and β-sheet cleft. The findings give us useful information regarding the interaction of oleuropein and α-lactalbumin which can be further used to produce functional foods.

Supercritical fluid extraction (SCFE) is a promising technique that has been attracted by some scientist recently due to the moderate operational condition. Moreover، SCFE products are pure and free of residual solvents. Mathematical modeling of supercritical extraction is a useful tool for deducing the SCF extraction systems، prediction of optimum operational conditions and system design variables، and scale-up to the pilot and industrial scales. A new mathematical model modified by Sovova، based on the concept of broken and intact cells، has been applied to understand the variables effect on extraction efficiency in a SCF extraction system. System was made in order to extract the essential oil from orange peel. This model simulates the experimental data points adequately for two separate time using combined pattern of phase equilibrium equations، solute/matrix interaction and internal diffusion rules in the solid particles. Model equations for plug flow are ordinary differential equations and are solved by matlab using numirical method. A number of physical parameters have been determined by experimental data fitting. Extraction curves have been presented on the form of extraction yield versus relative amount of passed solvent. The effect of operational parameters including grinding efficiency، bed void fraction، number of mixers and external mass transfer coefficient have been also investigated. The most desirable result is obtained from grinding efficiency and external mass transfer coefficient of 0. 7 and 0. 011 respectively، within 20 mixers. The model results present a good agreement with the experimental results. Average absolute deviation between experimental data and the modeling results is about 6%.