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Showing 4 results for Fourier Transform Infrared Spectroscopy

A.a. Pourbabaee ‎, M.a. Amoozegar ‎, S. Tavakoli , M. Rasooli ‎,
Volume 9, Issue 1 (1-2018)
Abstract

Aims: Carotenoids are a vast group of lipid-soluble pigments, which are produced by variety of microorganisms. The aim of this study was to compare the production of carotenoid pigments by prokaryotic isolates of Iranian saline ecosystems and identify superior isolate.
Materials & Methods: In this the experimental study, isolates were purified by culture-based methods and carotenoid extracts were analyzed by spectrophotometry in wavelength region of 400nm to 600nm. The total carotenoid content was estimated by spectrophotometry at λmax (490nm). Identity of bands was detremined by purification of bands by Thin Layer Chromatography (TLC) and analysis by High Pressure Liquid Chromatography (HPLC) and Fourier Transform Infrared Spectroscopy (FTIR).
Findings: Fourty-three isolates were obtained. Eight isolates were halotolerant bacteria, 8 isolates were moderately halophile, and 27 isolates were extremely halophile. All of the strains were capable of producing carotenoid compounds. Isolate M24 with 2054μg/g production was selected as superior isolate. Thin layer chromatography exhibited 6 colored bands in colored extract of this strain and the most concentrated band was purified. After purification by TLC and HPLC, spectrophotometry in UV range showed two pics at 530nm and 465nm as the highest absorbances, which were similar to UV absorbance of α-bacterioruberin. Phylogenetic analysis of 16S rRNA gene sequence of strain M24 showed that this strain had 98% similarity with Haloarcula amylolytica BD-3.
Conclusion: From Iranian Saline Ecosystems, 43 isolates are obtained. Eight isolates are halotolerant bacteria, 8 isolates are moderately halophile, and 27 isolates are extremely halophile. All of the isolates are capable of producing carotenoid compounds. Strain M24 is superior isolate, having 98% similarity with Haloarcula amylolytica BD-3.

Volume 19, Issue 126 (8-2022)
Abstract

Proteins are one of the most important food constituents due to their unique functional properties and health benefits. Among plant proteins, fenugreek seed protein is of great interest due to its high content of essential amino acids. The current study was carried out to optimize ultrasound-assisted extraction of fenugreek seed protein and evaluation of its functional, structural and antioxidant properties. The optimal conditions for protein extraction were ultrasonic power of 80 W and sonication time of 28.39 min which under these conditions, the predicted extraction yield was 8.65% which was in good agreement with the experimental value (8.57%). Amide A, amides type I, II, and III bands were observed in Fourier transform infrared spectrum. The solubility was pH-dependent. The water and oil absorption capacity was 6.24 and 2.72 mL/g, respectively. The lowest (44.66%) and highest (92.49%) foaming capacities were observed at pH 4.5 and 10, respectively. The highest emulsifying capacity (84.53%) was observed at pH 10, while the lowest (54.82%) was at isoelectric point. At the constant pH, the foam and emulsion stability decreased over time. The results revealed that ultrasound can be applied effectively to reduce the time of protein extraction process from fenugreek seeds. In addition, the fenugreek seeds extracted by using ultrasound have desirable functional and antioxidant properties that make it feasible for utilization in the food industry.

Volume 20, Issue 4 (10-2018)
Abstract

Poor organoleptic and physicalproperties of Low Fat Cheese (LFC) suggest the use of some hydrocolloids in its production. In this study, the effect of addition of Basil Seed Gum (BSG (into the structure of low-fat white brined cheese was investigated. To obtain a good view about the protein and polysaccharide interactions in cheese, Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared (FTIR) spectroscopy were also used. The results indicated that the incorporation of BSG into the cheese matrix and the creation of new interactions caused some changes in the cheese properties. There was considerable slump in the hardness value of the cheese samples containing BSG throughout ripening. The addition of BSG in the cheese matrix weakened its microstructure due to a decrease in the electrostatic attraction between the macromolecules, which was mainly a result of high salt concentration. Thermal properties and FTIR spectra of cheese samples were altered with polysaccharide incorporation as well as the ripening period.
 

Volume 25, Issue 2 (2-2023)
Abstract

 Malt beverage is one of the most popular drinks in the world. Recently, consumption of non-alcoholic beverages has expanded significantly in many countries. The permitted level of alcohol in malt beverage is less than 0.5% by Iranian National Standards. In this study, a method was developed to determine ethanol content in malt beverages by FTIR, equipped with Horizontal Attenuated Total Reflectance (H-ATR). Here, the Limit Of Detection (LOD) and Limit Of Quantification (LOQ) were 0.07% and 0.23%, respectively. The correlation coefficient of calibration curve was higher than 0.999. Fifty commercial malt beverages from six brands (five Iranian and one imported brand) and three types of flavored malt beverage (classic, equatorial, and lemon) were assessed. The average detected ethanol amount in samples was 0.19%, varying between 0.00-1.47percent. The results showed that the amount of ethanol in lemon malt drinks was more than the maximum permitted limit; that could be attributed to the usage of ethylene glycol for extraction of lemon flavor.

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