Showing 3 results for Emtyazjoo
Volume 6, Issue 1 (Spring 2022)
Abstract
Research Subject: In this study, Thiourea-functionalized super-paramagnetic nanoparticles were used as a heterogeneous catalyst in the Petasis-Borono Mannich reaction.
Research approach: In the first stage of this study, Fe3O4@SiO2 nanoparticles were synthesized as spherical core-shell nanoparticles such that Fe3O4 particles were considered as the core. Then in the next step, the characteristics of surface functional groups, crystal structure, magnetic properties, size and surface appearance of nanoparticles and the process of functionalizing the structure in layers, using infrared spectroscopy (FT-IR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) were examined, identified and analyzed. Then, to evaluate the efficiency of the structure, it was used as a catalyst in the Borono-Mannich reaction of potassium potash. Infrared spectroscopy (FT-IR) and hydrogen nuclear magnetic resonance spectroscopy (HNMR) were used to investigate the structure of the products.
Main results: The IR spectroscopy results showed that the peaks appearing in 568 cm-1 and 670 cm-1 were related to iron-oxygen bond, the peaks in 1092 and 800-950 cm-1 were related to silicon-oxygen bond, which indicates the formation of silicon layer on nanomagnetic particles and the validity of the reaction products. The results also showed that the amount of saturated magnetite in about 23 emu/g increased with increasing complex ligand. X-ray diffraction analysis showed that the index peaks of (2θ= 21.25˚, 37.29˚, 43.73˚, 52.56˚, 65.09˚, 69.73˚, 76.81˚) were realized and for certainty of the formation of the desired magnetic nanoparticles in crystalline phase were used. The results of SEM analysis showed the structure of nanoparticles in a spherical shape and EDX analysis confirmed the presence of elements in the structure which included sulfur. Also, the thermogravimetric analysis index showed approximately 7% decomposition coefficient. The first, second and third decomposition were observed 1% by weight (60°C), 5% by weight (200 to 300°C) and 1% by weight (350 to 700° C), respectively. The highest yield of 68% was measured with 40 mg catalyst in acetonitrile. The structure of thiourea was properly stabilized in a magnetic nanocatalyst.
Volume 14, Issue 1 (FALL 2023)
Abstract
Enriching human food using new technology such as lipid nanocarriers is a simple and accessible tool. Accordingly, the present study aimed to evaluate the sensory and production of healthy and useful food products to evaluate the enrichment of milk with zeaxanthin lipid nanocapsules and to evaluate its cryoprotectants. During experimental-laboratory research, zeaxanthin extraction from Spirulina platensis, and nanocarriers produced for milk enrichment were used as a food model system. Three samples of milk, milk enriched with lipid nanocarriers containing zeaxanthin, and milk enriched with lipid nanocarriers were examined (at similar concentrations of nanocarriers). In order to check the efficiency of produced nanocarriers, cold protective compounds (glucose, sorbitol, glycerin, lactose, and sucrose) were added to milk. Sucrose was recognized as the best cryoprotectants. Sensory evaluation of enriched milk was performed on a five-degree hedonic scale and different sensory parameters were examined. Data were analyzed using Minitab (v. 2016). Results No significant difference was observed between the sensory characteristics of control milk and milk enriched with nanocarriers (P<0.05). The lowest particle size and dispersion index were obtained in the coating of nanocarriers with cold protective compounds, respectively, 320.82 and 0.26 to 0.31. Zeta potential was reported as -6.03. By enriching milk with zeaxanthin-containing nanocarriers, in addition to visual and skin health, problems related to the lack of useful natural additives and insolubility of food products can be eliminated.
Mahrokh Mozafari, Mozhgan Emtyazjoo, Amir Ali Anvar,
Volume 20, Issue 138 (August 2023)
Abstract
The aim of the present study was to evaluate the viability of Lactobacillus rhamnosus IBRC-M 10754 in milk as a probiotic in cold storage and to evaluate its anti-diabetic effects. After bacterial culture in MRS medium and addition to milk, treatments containing 107, 108 and 109 cfu / ml of probiotic milk were prepared. Bacterial viability was performed for 5 days by sequential dilution and extensive culture in three replicates. Then, gavage containing probiotic-containing milk to Balb/C male rats that were infected with Streptozotocin was compared with anti-diabetic rats fed L. rhamnosus milk by measuring their blood glucose and weight. The results showed that the highest number of live bacteria in milk at 4Cº ,belonged to the first day of storage and there was no significant difference from the second day until the end of storage period. Overall, the bacterial population in milk decreased significantly (p≤0.05) over time. Addition of 109 cfu/ml primary inoculum showed that at the end of the fifth day the bacterial population in the milk was as high as that in the probiotic milk by the end of the cold storage. Mice weighing showed that the weight of control rats increased during the storage period, but diabetic rats decreased during this time. Milk with Lactobacillus inoculated in diabetic rats at different doses of inoculation resulted in a significant (P <0.05) decrease in blood glucose during their 21-day storage period. The decline of the fourteenth day of feeding probiotics is more evident.
