scholarly journals Potentials of enhancing the physicochemical and functional characteristics of Nigella sativa oil by using the screw pressing technique for extraction

2017 ◽  
Vol 68 (2) ◽  
pp. 188 ◽  
Author(s):  
S. F. Hamed ◽  
H. A. Shaaban ◽  
A. A. Ramadan ◽  
A. E. Edris
Keyword(s):  
Crude Oil ◽  
Oxidative Stability ◽  
Nigella Sativa ◽  
Stability Index ◽  
Volatile Oil ◽  
Biological Evaluation ◽  
Total Phenolic ◽  
Screw Pressing ◽  
Oil Fraction ◽  
Oxidative Stability Index

In the current investigation the crude oil of Nigella sativa was extracted from seeds using hydraulic and screw pressing techniques. Different parameters were evaluated in order to find out the appropriate technique to enhance the physicochemical and functional-related characteristics of the extracted crude oil. Results showed that the acid and peroxide values were significantly lower in the screw pressed oil (SPO) than in the hydraulic pressed oil (HPO). The total phenolic content of the SPO was significantly higher than that of HPO. Evaluation of the oxidative stability using the Rancimat test showed that SPO recorded a much higher oxidative stability index (40.07 h) than HPO (0.51 h). The yield of the volatile oil fraction and its contents of thymoquinone isolated from the SPO were higher than that from the HPO. Biological evaluation revealed that the SPO had significantly higher antimicrobial activity than HPO against Listeria monocytogenes and Staphylococcus aureus at 40 μL/well.

scholarly journals Selenium in Germinated Chickpea (Cicer arietinum L.) Increases the Stability of Its Oil Fraction

Plants ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 113 ◽  
Author(s):  
Daniela Guardado-Félix ◽  
Sergio O. Serna-Saldivar ◽  
Janet A. Gutiérrez-Uribe ◽  
Cristina Chuck-Hernández
Keyword(s):  
Sodium Selenite ◽  
Seed Oil ◽  
Stability Index ◽  
Selenium Concentration ◽  
Acid Value ◽  
Cicer Arietinum L ◽  
Oil Fraction ◽  
Oxidative Stability Index ◽  
The Stability ◽  
Excellent Source

Selenium is an essential mineral in human nutrition. In order to assess its effect on the stability of chickpea oil, seeds were germinated and tested with different amounts of sodium selenite (0.0, 0.5, 1.0 and 2.0 mg/100g seeds) for four days. Oil was extracted from sprouted chickpea and its physical properties, fatty acid profile (FAME), oxidative stability index (OSI), lipase and lipoxygenase (LOX) activities, cellular antioxidant activity (CAA), and phenolics and carotenoids were assessed and compared to chickpea seed oil. The amount of chickpea oil and its acid value (AV) increased during germination. The OSI increased by 28%, 46% and 14% for 0.5, 1.0 and 2.0 mg/100g compared with non-selenium treated sprouts. Phenolics increased up to 36% and carotenoids reduced by half in germinated sprouts with and without selenium compared to seeds. Carotenoids increased by 16% in sprouts treated with 1.0 mg/100 g selenium compared to their counterparts without selenium. FAME was not affected by treatments but samples with the highest selenium concentration increased lipase activity by 19% and decreased lipoxygenase activity by 55% compared with untreated sprouts. The CAA of oils increased by 43% to 66% in all germinated treatments compared with seeds. Results suggest that Se-enriched chickpea sprouts could represent an excellent source of oil with a high OSI and CAA, associated with a reduction in LOX activity and an increase in phenolics, respectively.

scholarly journals Preliminary Study: Comparison of Antioxidant Activity of Cannabidiol (CBD) and α-Tocopherol Added to Refined Olive and Sunflower Oils

Molecules ◽  
2019 ◽  
Vol 24 (19) ◽  
pp. 3485 ◽  
Author(s):  
Matilde Tura ◽  
Mara Mandrioli ◽  
Tullia Gallina Toschi
Keyword(s):  
Antioxidant Activity ◽  
Free Radicals ◽  
Oxidative Stability ◽  
Stability Index ◽  
Model Systems ◽  
Analytical Scheme ◽  
Oxidative Stability Index ◽  
Scavenging Capacity ◽  
Sunflower Oils ◽  
Forced Oxidation

This study evaluates the antioxidant activity of cannabidiol (CBD), added to model systems of refined olive (ROO) and sunflower (SO) oils, by measuring the peroxide value, oxidative stability index (OSI), electron spin resonance (ESR) forced oxidation, and DPPH• assays. Free acidity, a parameter of hydrolytic rancidity, was also examined. CBD was compared using the same analytical scheme with α-tocopherol. CBD, compared to α-tocopherol, showed a higher scavenging capacity, measured by DPPH• assay, but not better oxidative stability (OSI) of the oily systems considered. In particular, α-tocopherol (0.5%) showed an antioxidant activity only in SO, registered by an increase of more than 30% of the OSI (from 4.15 ± 0.07 to 6.28 ± 0.11 h). By ESR-forced oxidation assay, the concentration of free radicals (μM) in ROO decreased from 83.33 ± 4.56 to 11.23 ± 0.28 and in SO from 19.21 ± 1.39 to 6.90 ± 0.53 by adding 0.5% α-tocopherol. On the contrary, the addition of 0.5% CBD caused a worsening of the oxidative stability of ROO (from 23.58 ± 0.32 to 17.28 ± 0.18 h) and SO (from 4.93 ± 0.04 to 3.98 ± 0.04 h). Furthermore, 0.5% of CBD did not lower dramatically the concentration of free radicals (μM) as for α-tocopherol, which passed from 76.94 ± 9.04 to 72.25 ± 4.13 in ROO and from 17.91 ± 0.95 to 16.84 ± 0.25 in SO.

scholarly journals Prediction of Walnut Deterioration Using Kernel Oxidative Stability

Foods ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1207
Author(s):  
Filipa Simoes Grilo ◽  
Yanisa Srisaard ◽  
Selina C. Wang
Keyword(s):  
Oxidative Stability ◽  
Stability Index ◽  
Operating Parameters ◽  
Operational Parameters ◽  
Oxidation Method ◽  
Accelerated Oxidation ◽  
Oxidative Markers ◽  
Kernel Quality ◽  
Oxidative Stability Index ◽  
Parameters Analysis

Monitoring walnut oxidation is essential to control walnut quality during storage. An accelerated oxidation method for differentiating the oxidative stability index (OSI) of walnut kernels was examined and the effects of instrument operational parameters such as temperature and airflow were evaluated. Four cultivars, Chandler, Solano, Durham, and Howard were analyzed at 110, 120, and 130 °C with 15, 20, and 25 L h−1 airflow. Analysis using 110 °C with 25 L h−1 yielded the lowest coefficients of variance (4.4) than other operational parameters; analysis using the same temperature at lower airflow, 15 L h−1, yield the highest coefficient of variance (10.5). Kernel OSI values were independent of airflow, however, dependence of temperature coefficient and Q10 were demonstrated. The results from selected parameters were correlated with fat and moisture content, peroxide value, UV absorbances, oil oxidative stability, hexanal, and rancidity to establish the relationships between OSI values and quality changes during storage. Using 0.5 g of ground kernels, at 110 °C with 25 L h−1 airflow gave a lower coefficient of variance and higher correlation with kernel quality and oxidative markers comparing to other combinations of operating parameters.

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