Monitoring of Hazelnut oil quality during thermal processing in comparison with extra virgin olive oil by using ATR-FTIR spectroscopy combined with chemometrics

Hazelnut oil (HO), which is not widely used because its healthy properties are not fully known yet, is an excellent nutrient due to its high content of monounsaturated fatty acids and antioxidants. In this study, the effects of thermal processing on the quality of HO in comparison to extra virgin olive oil (EVOO), which is one of the healthiest and heat-resistant oils, were investigated using Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy. Oil samples were heated at a frying temperature (180 degrees C) for 24 h in periods of 8 h per day and alterations in the spectra of these oils sampled every 2 h were evaluated. The heating process caused decreases in the areas of the bands at 3007 and 722 cm(-1) and the area ratios of 3007/2854 and 722/2854 cm(-1) and increases in the areas of the bands at 987 and 965 cm(-1) and the area ratio of 965/2854 cm(-1) in both oils suggesting the conjugation and cis-trans isomerization of unsaturated fatty acids. In addition, heating caused increases in the areas of the bands at 3475 and 1744 cm(-1) and the ratios of 3475/2854 cm(-1) and 1744/2854 cm(-1), a shift to a lower value in the wavenumber and a broadening of the 1744 cm(-1) band indicating the formation of primary and secondary oxidation products in the heated oils, which were also supported by chemical studies. Most of these changes began earlier in EVOO and all occurred to a higher extent, revealing that HO has a higher thermal stability than EVOO. Principal component analysis and hierarchical cluster analysis confirmed that HO is more resistant to heat than EVOO. These results showed that HO is superior to EVOO and it could be used for frying as a healthier and cheaper oil alternative. This study also indicated that oil oxidation could be monitored easily and rapidly via ATR-FTIR spectroscopy. (C) 2021 Elsevier B.V. All rights reserved.WOS:0007122193000042-s2.0-85116882426PubMed: 3464912

The effects of radioprotectant and potential antioxidant agent amifostine on the structure and dynamics of DPPC and DPPG liposomes

Agents capable of scavenging ROS have attracted attention recently because of their potential use as anti oxidative agents. Amifostine, a ROS scavenger, has the potential to be used as an antioxidant in therapeutic applications. In this study, the effect of amifostine on neutral zwitterionic dipalmitoylphosphatidylcholine (DPPC) and anionic dipalmitoylphosphatidylglycerol (DPPG) model membranes' structure and dynamics is aimed to be examined by Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). Our results revealed that amifostine at concentrations used (1-24 mol%) does not induce any important alteration in the shape of phase transition curve and phase transition temperature in the DPPC and DPPG membranes. High concentrations of amifostine slightly increased the acyl chain flexibility of DPPC membranes in the liquid crystalline phase and DPPG membranes in the gel phase. A lessening in the dynamics of DPPC liposomes was observed for all concentrations of amifostine in both phases but slight dual effect was observed only in the gel phase as a decrease in dynamics at low concentrations and an increase at higher concentrations of amifostine in DPPG liposomes. Additionally, strong hydrogen bonding was observed for both C=O and PO2- groups in case of DPPC and for PO2- groups in case of DPPG. Dehydration around the C=O regions occurred in case of DPPG. Accordingly, amifostine is proposed to be interacting strongly with zwitterionic and negatively charged membrane head groups and glycerol backbone in all concentrations and because of this interaction it causes some changes in lipid order and dynamics especially at high concentrations

An Evaluation of Damages Caused by Doxorubicin in Liver Tissue and Potential Protective Effect of Propolis on These Damages

Objective: Doxorubicin (DOX), one of the chemotherapeutic drugs utilized in cancer treatment, has limited clinical use due to its serious toxic effects on non-target organs. The purpose of this study is to reveal the harmful effects of DOX in rat liver and the possible protective effect of propolis (PRPLS), a mixture of various herbal products collected by honeybees, on these damages by Attenuated Total Reflection-Fourier Transformation Infrared (ATR-FTIR) spectroscopy. Methods: Sprague dawley rats were separated into 4 groups; control, DOX (cumulative dose: 15 mg/kg), PRPLS (200 mg/kg) and DOX + PRPLS. The rats were given 200 mg/kg PRPLS by oral gavage daily for 20 consecutive days and 2.5 mg/kg DOX intraperitoneally on days 10, 12, 14, 16, 18 and 20 of the experiment. 24 hrs after the last administrations, liver samples were collected and examined by ATR-FTIR spectroscopy. Results: DOX caused a decrease in the amount of glycogen and nucleic acids, an increase in the amount of lipids and proteins and some important changes in the metabolism, structure and conformation of these molecules in the liver. DOX also induced lipid peroxidation, an increase in membrane fluidity, a decrease in membrane order and protein denaturation. PRPLS did not induce any toxic effect on the liver when it was given alone and PRPLS administered before DOX was not effective to eliminate these harmful effects of DOX. Conclusions: DOX caused significant structural and compositional changes in liver tissue and PRPLS was inadequate to prevent these changes at the dose and time used here.Duzce University-Research Fund, BAP [2019.05.01.936]This work was supported by the Duzce University-Research Fund, BAP (2019.05.01.936)

Crystallization of CaAl4O7 and CaAl12O19 powders

Calcium is always present in alumina systems as an unintentional (or intentional) dopant, and yet the fundamental effect of its incorporation into the aluminas is not well understood, and is further complicated by the presence of Si. The synthesis of powders of two calcium aluminate phases (CaAl4O7, which is also known as CaO 2Al2O3 or CA2, and CaAl12O19, which is also known as CaO 6Al2O3 or CA6) has been investigated using low-temperature chemical-processing techniques. The crystallization of these powders from the amorphous precursor has been examined using various characterization techniques. The precursors for the powders were prepared by mixing stoichiometric proportions of the nitrate salts into a 5 wt% aqueous solution of poly(vinyl alcohol). Conversion of the amorphous precursors to crystalline powders and the subsequent phase transitions were monitored using differential thermal analysis (DTA), thermogravimetric analysis (TGA) and powder X-ray diffractometry (XRD). While powders with CA2 stoichiometry crystallized directly at 883C, amorphous powders with CA6 stoichiometry first crystallized into an intermediate structure without partitioning and then transformed into CA6 at 1175C. Fully and partially crystallized powders were analyzed using transmission electron microscopy and electron energy-loss spectroscopy (EELS). Measured near-edge structures (Al-L2,3, Ca-L2,3 and O-K) are presented for the CA2, -Al2O3 and CA6 phases. The intermediate phase, identified as -Al2O3, was found to accommodate a significant concentration of Ca

Acute effects of ultrafiltration on aortic mechanical properties determined by measurement of pulse wave velocity and pulse propagation time in hemodialysis patients

Objective: The effects of acute hemodialysis session on pulse wave velocity are conflicting. The aim of the current study was to assess the acute effects of ultrafiltration on the aortic mechanical properties using carotid-femoral (aortic) pulse wave velocity and pulse propagation time

Characterizing CA(2) and CA(6) using elnes

Calcium aluminates, compounds in the CaO-Al2O3 phase system, are used in high-temperature cements and refractory oxides and have wide range of potential technological applications due to their interesting optical, electrical, thermal, and mechanical properties. They are used in both crystalline and glassy form; the glass is an isotropic material while the crystalline materials may be highly anisotropic. This paper will consider two particular crystalline materials, CA(2) and CA(6), but the results should be applicable to all calcium aluminates. Although CA(2) and CA(6) crystals contain the same chemical species, Ca, Al, and O, the coordination and local environments of these species are different in the two structures and hence they show very different energy-loss near-edge structures (ELNES) when examined by electron energy-loss spectroscopy (EELS) in the TEM. The data obtained using ELNES can effectively provide a fingerprint for each compound and a map for their electronic structure. Once such fingerprints are obtained, they can be used to identify nano-sized particles/grains or material at interfaces and grain boundaries. In the present study, the local symmetry fingerprints for CA(2) and CA(6) structures are reported combining experimental spectra with electronic-structure calculations that allow the different features in the spectra to be interpreted. Al-L-2,L-3 and O-K edge core-loss spectra from CA(2) and CA(6) were measured experimentally using electron energy-loss spectroscopy in a monochromated scanning transmission electron microscope. The near-edge structures were calculated for the different phases using the orthogonalized linear combination of atomic-orbitals method, and took account of core-hole interactions. It is shown that CA(2) and CA(6) structures exhibit distinctive experimental ELNES fingerprints so that these two phases can be separately identified even when present in small volumes