The effect of fatty acid unsaturation on the antioxidant activity of β-carotene and α-tocopherol in hexane solutions

1995 ◽  
Vol 18 (5) ◽  
pp. 943-948 ◽  
Author(s):  
Paola Palozza ◽  
Chiara Luberto ◽  
Gianna Maria Bartoli
1998 ◽  
Vol 80 (1) ◽  
pp. 67-73 ◽  
Author(s):  
Gerard S. Oostenbrug ◽  
Ronald P. Mensink ◽  
Monique D. M. Al ◽  
Adriana C. van Houwelingen ◽  
Gerard Hornstra

During pregnancy, maternal plasma concentrations of the peroxidation-susceptible polyunsaturated fatty acids (polyenes) increase. In addition, the proportion of polyenes is higher in neonatal plasma than in maternal plasma. To study whether these increased amounts of polyenes affect antioxidant levels, we measured lipid-soluble antioxidants in maternal and neonatal plasmas obtained during thirty-five normal pregnancies. These values were then related to the degree of phospholipid-fatty acid unsaturation. Maternal plasma levels of tocopherols and lutein increased during pregnancy, as assessed at 14, 22, and 32 weeks of gestation. However, β-carotene levels decreased, and levels of other carotenoids remained unchanged. Retinol levels were only decreased at 32 weeks of gestation. The value for α-tocopherol: phospholipid-polyene unsaturation index (UI) also increased during pregnancy, despite the observed increase in UI. Corresponding ratios for several carotenoids and retinol, however, decreased during pregnancy. After delivery, maternal plasma levels of δ-tocopherol and β + γ-tocopherol, as well as β + γ-tocopherol: UI values, were lower than values at 32 weeks of gestation. Umbilical-cord plasma antioxidant levels and antioxidant: UI values, except retinol: UI, were significantly lower than maternal values. Significant and consistent cord ν. maternal correlations were observed for plasma levels of β + γ-tocopherol, lutein and β-carotene, but not for δ-tocopherol, α-tocopherol, lycopene, α-carotene, and retinol. In conclusion, although during pregnancy maternal plasma tocopherol levels increased concurrently with, or more than, fatty acid unsaturation in plasma phospholipids, the decrease in carotenoid: UI values during gestation, the decrease in maternal plasma levels of δ-tocopherol and β + γ-tocopherol after delivery, and the low neonatal antioxidant levels merit further investigation.


Author(s):  
Erhan Kaplaner ◽  
Mehmet Hüseyin Singeç ◽  
Mehmet Öztürk

Edible mushrooms are one of the important food source because of their tastes, and having high concentration of fatty acids and the other nutrients. In this study, fatty acid composition and antioxidant properties of Tricholoma imbricatum and T. focale were determined. The fatty acids were analysed by GC, and GC-MS while the antioxidant activity was tested using five complimentary methods; namely, β-carotene-linoleic acid, DPPH scavenging, ABTS scavenging, CUPRAC and metal chelating assays. Eight fatty acids were determined in hexane extract, and oleic acid was the major fatty acid with 46.4% and 35.0%, respectively. Palmitic acid (12.8%, and 5.12%) and lineloic acid (28.2% and 31.0%) were also detected in high amounts. In DPPH.scavenging and ABTS·+ scavenging assays, the methanol extract of T. imbricatum (IC50: 0.12±0.01 mg/mL for both assay) showed better antioxidant activity than those of T. focale (IC50>0.8±0.01, and IC50: 0.21±0.01 mg/mL). All extracts of T. focale exhibited good activity in β-carotene-linoleic acid assay while only the hexane extract of T. imbricatum showed activity. Both mushroom indicated moderate in cupric reducing power. Since the mushrooms are nontoxic and edible, both can be used in food industry as preservatives.


Antioxidants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1081
Author(s):  
Matilda Rădulescu ◽  
Călin Jianu ◽  
Alexandra Teodora Lukinich-Gruia ◽  
Marius Mioc ◽  
Alexandra Mioc ◽  
...  

The investigation aimed to study the in vitro and in silico antioxidant properties of Melissa officinalis subsp. officinalis essential oil (MOEO). The chemical composition of MOEO was determined using GC–MS analysis. Among 36 compounds identified in MOEO, the main were beta-cubebene (27.66%), beta-caryophyllene (27.41%), alpha-cadinene (4.72%), caryophyllene oxide (4.09%), and alpha-cadinol (4.07%), respectively. In vitro antioxidant properties of MOEO have been studied in 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging, and inhibition of β-carotene bleaching assays. The half-maximal inhibitory concentration (IC50) for the radical scavenging abilities of ABTS and DPPH were 1.225 ± 0.011 μg/mL and 14.015 ± 0.027 μg/mL, respectively, demonstrating good antioxidant activity. Moreover, MOEO exhibited a strong inhibitory effect (94.031 ± 0.082%) in the β-carotene bleaching assay by neutralizing hydroperoxides, responsible for the oxidation of highly unsaturated β-carotene. Furthermore, molecular docking showed that the MOEO components could exert an in vitro antioxidant activity through xanthine oxidoreductase inhibition. The most active structures are minor MOEO components (approximately 6%), among which the highest affinity for the target protein belongs to carvacrol.


2014 ◽  
Vol 955-959 ◽  
pp. 387-389 ◽  
Author(s):  
Bao Qing Wang

Antioxidant activities of acetone and ethyl acetate extracts from Metaplexis japonica Makino, one of famous medicine plants in the eastnorth region of China, named luomo in Chinese, were examined by a DPPH (1,1-Diphenyl-2-picrylhydrazyl) radical-scavenging assay and a β-carotene-linoleic acid test. In DPPH, the antioxidant activity of the acetone extracts, ethyl acetate extracts and derivative were IC50 were 313.21, 266.92 and 118.78μg/mL, respectively. In the β-carotene-linoleic acid test, IC50 were 285.09, 351.57 and 123.89μg/mL. It was concluded that Metaplexis japonica Makino and its derivatives might be a potential natural source of antioxidants .


2009 ◽  
Vol 2 (2) ◽  
pp. 99-106 ◽  
Author(s):  
Nurten Ozsoy ◽  
Eda Candoken ◽  
Nuriye Akev

In order to demonstrate whether the known biological effects ofAloe vera(L.) Burm. fil. could correlate with the antioxidant activity of the plant, the antioxidant activity of the aqueous leaf extract was investigated. The present study demonstrated that the aqueous extract fromA. veraleaves contained naturally occuring antioxidant components, including total phenols, flavonoids, ascorbic acid, β-carotene and α-tocopherol. The extract exhibited inhibitory capacity against Fe3+/ascorbic acid induced phosphatidylcholine liposome oxidation, scavenged stable DPPH•, ABTS•+and superoxide anion radicals, and acted as reductant. In contrast, the leaf inner gel did not show any antioxidant activity. It was concluded that the known beneficial effects ofAloe veracould be attributed to its antioxidant activity and could be related to the presence of phenolic compounds and antioxidant vitamins.


2020 ◽  
Vol 82 (6) ◽  
pp. 71-78
Author(s):  
Zita Letviany Sarungallo ◽  
Budi Santoso ◽  
Risma Uli Situngkir ◽  
Mathelda Kurniaty Roreng ◽  
Meike Meilan Lisangan

Refining of crude red fruit oil (CRFO) through the degumming and neutralization steps intended to produce oil free of impurities (non triglycerides) such as phospholipids, proteins, residues and carbohydrates, and also reducing the amount of free fatty acids (FFA). This study aims to determine the effect of red fruit oil purification through degumming and neutralization stages on chemical properties, fatty acid composition, carotenoid content and tocopherol of red fruit oil (RFO). The results showed that degumming of CRFO did not affect the decrease in water content, FFA levels, peroxide numbers, iodine values, carotenoids and tocopherols content; but decrease in levels of phosphorus, β-carotene and α-tocopherol. Neutralization of degummed-RFO (DRFO) did not affect the decrease in water content, iodine value, carotenoid, tocopherol and α-tocopherol; but the FFA levels, peroxide number, phosphorus and β-carotene levels decreased significantly. The fatty acid composition of RFO was dominated by unsaturated fatty acids (± 75%), which increases through degumming and neutralization stages. β-carotene is more sensitive than α-tocopherol during refining process of crude oil, but in general, this process can improve the RFO quality.


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