A PROPOSED MODIFICATION OF EMMERIE'S IRON-DIPYRIDYL METHOD FOR DETERMINING THE TOCOPHEROL CONTENT OF OILS

1940 ◽  
Vol 18b (12) ◽  
pp. 405-409 ◽  
Author(s):  
W. E. Parker ◽  
W. D. McFarlane

By treating a petrol ether solution of wheat-germ oil with 85% sulphuric acid, centrifuging, and washing the supernatant petrol ether with dilute alkali, carotenoids and other substances that interfere with the iron-dipyridyl method for determining tocopherol are removed. Tocopherol is not affected by the treatment. The tocopherol content of the solution is finally determined by a modification of Emmerie's method.

2020 ◽  
Vol 58 (3) ◽  
pp. 348-355
Author(s):  
Derya Arslan ◽  
M. Kürşat Demir ◽  
Ayşenur Acar ◽  
Fatma Nur Arslan

Research background. Utilization of wheat germ (WG) and wheat germ oil (WGO) is limited due to high enzymatic activity and unsaturated fatty acids and therefore stabilization techniques are needed to overcome this problem. Experimental approach. In this study, the effects of stabilization methods (dry convective oven heating at 90 and 160 oC and microwave radiation under 180 W and 360 W output power, and steaming by autoclave) on both WG and WGO were evaluated. Results and conclusions. Steaming caused the most dramatic changes on lipoxygenase, free fatty acids (FFA), DPPH radical scavenging activity, tocopherols and tocotrienols. The lowest peroxide values (PVs) were measured in oils of convectional heating (160 oC) and steaming treatments which were performed at temperatures above 100 oC. However, para-anisidine values (pAVs) of samples treated at higher temperatures were considerably greater than those of stabilized at lower temperatures. Oven heating at 160 oC was also one of the most effective treatments on inactivation of lipoxygenase coming after steaming. Steaming also induced a significant reduction in total tocopherols which was directly associated with the greater lost in β-tocopherol content. On the contrary γ- and δ-tocopherols and tocotrienol homologs were abundant with higher amounts in steam applied samples. α-Tocopherol and γ-tocotrienol were the most resistant isomers to stabilization processes. Novelty and scientific contribution. This study shows that the high temperature oven heating method, which is widely used in the industry for thermal stabilization of wheat germ, does not provide an advantage in oxidative stability compared to steaming and microwave applications. Steaming delayed oxidation in germ, while further inhibiting lipoxygenase activity. Moreover, tocotrienols were more conservable. In industrial application, low power in microwave (180 W instead of 360 W), lower temperature in oven heating (90 instead of 160 oC) would be preferable.


Author(s):  
Hadeer Zakaria ◽  
Tarek M. Mostafa ◽  
Gamal A. El-Azab ◽  
Nagy AH Sayed-Ahmed

Abstract. Background: Elevated homocysteine levels and malnutrition are frequently detected in hemodialysis patients and are believed to exacerbate cardiovascular comorbidities. Omega-3 fatty acids have been postulated to lower homocysteine levels by up-regulating metabolic enzymes and improving substrate availability for homocysteine degradation. Additionally, it has been suggested that prevention of folate depletion by vitamin E consumption decreases homocysteine levels. However, data on the effect of omega-3 fatty acids and/or vitamin E on homocysteine levels and nutritional status have been inconclusive. Therefore, this study was planned to examine the effect of combined supplementation of fish oil, as a source of omega-3 fatty acids, with wheat germ oil, as a source of vitamin E, on homocysteine and nutritional indices in hemodialysis patients. Methods: This study was a randomized, double-blind, placebo-controlled trial. Forty-six hemodialysis patients were randomly assigned to two equally-sized groups; a supplemented group who received 3000 mg/day of fish oil [1053 mg omega-3 fatty acids] plus 300 mg/day of wheat germ oil [0.765 mg vitamin E], and a matched placebo group who received placebo capsules for 4 months. Serum homocysteine and different nutritional indices were measured before and after the intervention. Results: Twenty patients in each group completed the study. At the end of the study, there were no significant changes in homocysteine levels and in the nutritional indices neither in the supplemented nor in the placebo-control groups (p > 0.05). Conclusions: Fish oil and wheat germ oil combination did not produce significant effects on serum homocysteine levels and nutritional indices of hemodialysis patients.


2021 ◽  
Author(s):  
Anam Khalid ◽  
Muhammad Sohaib ◽  
Muhammad Tahir Nadeem ◽  
Farhan Saeed ◽  
Ali Imran ◽  
...  

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 662
Author(s):  
Sabrin Abdelrahman Morshedy ◽  
Ahmed M. Abdelmodather ◽  
Mohamed M. Basyony ◽  
Soliman A. Zahran ◽  
Mohamed A. Hassan

Vegetable oils are a source of natural antioxidants, including tocopherols, sterols, phenolic compounds, coenzymes, and polyunsaturated fatty acids that provide nutritional value, organoleptic properties, and significantly delay or prevent lipid oxidation. Eighty-four V-line rabbits at 5 weeks of age with an initial body weight (BW) of 535.60 ± 13.48 g were assigned randomly to four experimental groups (seven replicates in each group with three rabbits each). The first group served as a control and received 0.3 mL/kg BW of distilled water (CON), while the second and third groups received 0.3 mL/kg BW of rocket seed oil (RSO) and wheat germ oil (WGO), respectively. The fourth group received a mixture of oils consisting of 0.15 mL of RSO and 0.15 mL of WGO/kg BW (MOs). The experiment lasted 7 weeks. The study investigated the effects of RSO, WGO, and their mixture on growth performance, feed utilization, antioxidant status, and immune response of growing rabbits. The results indicated that the rabbits that were administered orally with RSO and WGO or their mixture had higher (p ≤ 0.05) final BW, weight gain, and average daily gain when compared to the control group. In addition, the feed conversion ratio improved significantly with RSO, WGO, and MOs treatments. Different oil treatments improved nutrient digestibility, nutritive value, and nitrogen balance. Moreover, the rabbits that received RSO, WGO, and their mixture had an improvement the meat fatty acid composition compared to the control rabbits. Oral administration of RSO, WGO, and their mixture significantly improved serum protein fractions, decreased blood urea nitrogen, and had a positive effect on serum total lipids, HDL-c, and LDL-c. Furthermore, the treatments of RSO, WGO, and MOs had a significant improvement in the antioxidative status and immune response.


1962 ◽  
Vol 40 (3) ◽  
pp. 371-374 ◽  
Author(s):  
Claude Ritchot ◽  
J. E. McFarlane

Lipid other than sterol improves the growth and development of nymphs of Acheta domesticus (L.), as shown by the effect of adding wheat germ oil and linoleic acid to the diet. Such lipid is also necessary for reproduction: the effect appears to be on the male, but may also be on the female.


Science ◽  
1936 ◽  
Vol 83 (2157) ◽  
pp. 421-421
Author(s):  
Oliver H. Emerson ◽  
Gladys A. Emerson ◽  
Herbert M. Evans

2021 ◽  
Vol 24 (6) ◽  
pp. 706-715
Author(s):  
Raghda Zakaria ◽  
Raad J. Musa ◽  
Jabar Faraj ◽  
Zead H. Mahmoud ◽  
Hamdoon A. Mohamme

1951 ◽  
Vol 29 (2) ◽  
pp. 71-79 ◽  
Author(s):  
A. Lemonde ◽  
R. Bernard

A purified diet suitable for the study of the qualitative amino acids requirements of the larvae of the Coleoptera Tribolium confusum is presented. The composition of the diet is as follows: amino acid mixture 20%, cornstarch 75.5%, cholesterol 1%, wheat germ oil 1.5%, salt mixture No. 2 U.S.P. XII 2%, yeast 0.5%, vitamin mixture M.V.–II. In presence of amino acids, glucose cannot be used as a source of hydrocarbon. The mixture is very hygroscopic, develops a brown color, and is apparently toxic to the larvae. The importance of choline as a growth factor is demonstrated. Wilson's Liver Fraction L or Liver Concentrate 1: 20 cannot replace this vitamin. Yeast appears to contain unknown factors for it improves growth when added to a diet already supplemented with vitamins known to be essential for the larvae. A mixture of 19 crystalline amino acids known to occur in casein satisfies the nitrogen requirements of the larvae of T. confusum equally as well as purified casein.


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