Blending of Soybean Oil with Selected Vegetable Oils: Impact on Oxidative Stability and Radical Scavenging Activity

This study was designed to determine the polyphenolic contents of Eucommia ulmoicles Oliv leaf extracts and evaluate their antioxidant activities in vitro. All the extracts were evaluated for their radical scavenging activity by the DPPH method and their oxidative-retarding efficiency in vegetable oils. It was observed that the highest values were found in 70% MeOH extracts for total phenolic content as gallic acid. A good correlation between antioxidant activity and total phenol content in the extracts was found. The extraction yield, total phenol content and radical scavenging activity were increased and peroxide formation in vegetable oils were decreased with the graded solvent concentration of MeOH. The phenolic compound yield ranged from 2.45 to 11.35% and the total phenol content increased from 34.51 mg/g to 47.68 mg/g. DPPH scavenging activity increased from 56.32% to 90.37% as MeOH concentration increased. Compared to the control (70.45 meq/kg), 70% MeOH fraction with 47.68 mg/g phenolic compounds shows much stronger antioxidant ability (30.12 meq/kg) in vegetable oil system.

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Smartphone-based colorimetric determination of DPPH free radical scavenging activity in vegetable oils

10.22616/rrd.26.2020.016 ◽

2020 ◽

Author(s):

Sanita Vucane ◽

◽

Martins Sabovics ◽

Lauris Leitans ◽

Ingmars Cinkmanis ◽

...

Keyword(s):

Free Radical ◽

Vegetable Oils ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Free Radical Scavenging ◽

Biologically Active ◽

Free Radical Scavenging Activity ◽

Scavenging Activity ◽

Dpph Method

Free radicals can rapidly and irreversibly oxidize various structures, including unsaturated fatty acids in vegetable oils, which affect the sensory properties. Spectrophotometry is the most widely used method for the determination of free radical scavenging activity (RSA) using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Barrier to the further use of classical analytical methods to analyze biologically active compounds in foodstuffs is that equipment requires high cost and has limited mobility. One of solutions is to replace classical methods, such as spectroscopy, with smartphonebased colorimetry. Huawei P30 Lite smartphone was used for colorimetric detection. The free radical scavenging activity (RSA) in vegetable oil was detected using an application ‘Color Picker’, with image matching algorithm for red, green, and blue (RGB) model. RSA was expressed as percentage and measured by the DPPH method. The aim of the study was to determinate the total free radical scavenging activity with smartphone-based colorimetry. For the data comparison and accuracy spectrophotometer as analytical optical instrument was used. Eleven vegetable oils: sea buckthorn, sunflower, rice, macadamia nut, hemp, corn, grape, linseed, rapeseed, olive and milk thistle oils were selected for analysis. The best results with no significant differences (p>0.05) compared to smartphone-based colorimetry from spectrophotometry were determined using RG values. The poor results were detected by using B value (p<0.05) and were not suitable for determination of RSA. Smartphone-based colorimetry can be used in the determination of the RSA in vegetable oils.

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Free Radical Scavenging Activity of Carbonyl-Amine Adducts Formed in Soybean Oil Fortified with Phosphatidylethanolamine

Molecules ◽

10.3390/molecules25020373 ◽

2020 ◽

Vol 25 (2) ◽

pp. 373

Author(s):

Jana Goritschnig ◽

Klaudia Tadus ◽

Jürgen König ◽

Marc Pignitter

Keyword(s):

Oxidative Stability ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Free Radical Scavenging ◽

Scavenging Activity ◽

Reaction Products ◽

Dpph Assay ◽

Amine Adducts ◽

Lipid Aldehydes ◽

Cold Pressed

Non-enzymatic browning reactions between lipid aldehydes and aminophospholipids might play an important role in the oxidative stability of cold-pressed vegetable oils. We, therefore, aimed to study the Maillard-type reaction between hexanal, a lipid oxidation product of linoleic acid, and phosphatidylethanolamine (PE (16:0/18:1)) at a ratio of 2:1 at conditions representative of the extraction of cold-pressed soybean oils (CPSBO) and determine the radical scavenging activity of the carbonyl-amine adducts with the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The reaction product, 2-pentyl-3,5-dibutyl-dihydropyridine, could be identified by means of LC-ESI-QTOF-MS/MS. The formation of this nitrogen-containing heterocycle significantly increased with time and temperature (p < 0.05). The products formed during the carbonyl-amine reaction between PE (16:0/18:1) and hexanal at 60 °C showed a radical scavenging activity of approximately 20% (p < 0.05). The fraction, containing 2-pentyl-3,5-dibutyl-dihydropyridine, contributed to, but was not solely responsible for, the radical scavenging activity (p < 0.05). Incubation of CPSBO fortified with PE (16:0/18:1) at 60 °C for 60 min had the strongest radical scavenging activity of 85.1 ± 0.62%. Besides 2-pentyl-3,5-dibutyl-dihydropyridine, other carbonyl-amine adducts might impact the radical scavenging activity of CPSBO as well. The oxidative stability of CPSBO might be increased by promoting the formation of carbonyl-amine reaction products, such as 2-pentyl-3,5-dibutyl-dihydropyridine.

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Antioxidants on Radical-Scavenging Activity of Vegetable Oil

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.781-784.1776 ◽

2013 ◽

Vol 781-784 ◽

pp. 1776-1779

Author(s):

Li Qin Jiang

Keyword(s):

Soybean Oil ◽

Olive Oil ◽

Vegetable Oil ◽

Radical Scavenging Activity ◽

Virgin Olive Oil ◽

Radical Scavenging ◽

Total Phenol Content ◽

Scavenging Activity ◽

Comparable Activity ◽

The Stability

The aim of this study was to investigate the effect of antioxidants of soybean oil and virgin olive oil during heating. Tocopherol and total phenol content in oils were determined by HPLC and Folin test, respectively. Antioxidant activity was measured with scavenging-activity (RSA) of free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH·) by spectrophotometer. Among the antioxidants studied, comparable activity was found between Trolox and tocopherol, while activity of phenol was low in the study. Tocopherol compounds contribute the RSA of soybean oil, and the RSA of virgin olive oil was from phenol compound as well as tocopherols. Our study showed the variety and content of antioxidants influence RSA of vegetable oils, which concerned the stability and nutrition quality of vegetable oil.

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