Tocotrienol

Tocotrienols ( T3 short or TCT) hot four forms of vitamin E. They correspond to the tocopherols in the function group ( alpha, beta, gamma, delta ) but have a triunsaturated rest on. Tocotrienols always act like vitamin E and as an antioxidant. They also have some functions are not found in tocopherols.

Occurrence

Tocotrienols are widely distributed in plants and appear mostly in combination with other vitamin D analogs.

Foods containing high levels of tocotrienols are:

  • Cranberry (170 mg/100 g as alpha -tocotrienol )
  • Annattosaat (143 mg/100 g, mainly as a delta -tocotrienol )
  • Chinese horse chestnut (96 mg/100 g)
  • Palm oil ( Red) ( 40-140 mg/100 g)
  • Barley oil ( 23-92 mg/100 g)
  • Grape seed oil ( 33-75 mg/100 g)
  • Rice bran oil (30 mg/100 g)
  • Macadamia nut oil (5-9 mg/100 g)
  • Wheat germ oil (4 mg/100 g)
  • Coconut oil (3.9 mg/100 g)

In annatto seeds, red palm oil, and grapeseed oil tocotrienols make even from the vast amount of vitamin E, while many other vegetable oils have only a relatively small percentage of tocotrienols.

Due to the prevalence occurrence in barley ( also grapes, annatto oil and palm oil ) were tocotrienols for millennia normal part of the diet.

Construction

Tocotrienols include a hydroxylated at position 6 of the chroman ring, is linked to position 2, with an unsaturated side chain. The derivatives are classified depending on the methylation of the chroman nucleus in an α -, β -, γ - or δ - form. Tocotrienols are natural hand still in a RRR configuration.

Differences of tocotrienols to tocopherols

Chemically be tocotrienols differ only in the side chain of the tocopherols. While it is completely saturated at the latter, tocotrienols have a tri-unsaturated side chain. These unsaturated double bonds lead to a substantially increased vitamin activity in the tocotrienols. This is explained by:

  • A faster reactivation of chromanoxyl radicals,
  • A more uniform distribution in the membrane layers,
  • Greater integration into the membrane lipids that allows more effective interaction of chromanols with the lipid radicals.

Antioxidant effect

Alpha -tocotrienol, in comparison to alpha -tocopherol in vitro, a 40 - to 60 -fold higher activity as an antioxidant against the lipid peroxidation in cell membranes.

Bioavailability

When taken orally, tocotrienols are absorbed only about 30% as good as tocopherol in the body. They are also excreted faster. Tocotrienols are but much better than absorbed through the skin .. The intake of alpha- tocopherol, dl- α in particular synthetic -tocopheryl acetate, tocopherols, blocks the absorption of tocotrienols in the diet and accelerates the degradation rate in the tissue.

Technical recovery

Tocotrienols are currently being produced in large scale from red palm oil, rice germ oil and from annatto seeds. The concentrated Vitamin oil is called TRF ( Tocotrienol Rich Fraction ). The composition of the isomers varies considerably depending on the source part.

Effect on NF-kappaB

Tocotrienols have a significant impact on the transcription factor NF-KB which is also called a redox- sensitive transcription factor. NF -kB regulates genes that play a central role in inflammation, apoptosis and aging. In the current state of research is this property, which is predominantly found in the isomer gamma- tocotrienol and delta -tocotrienol, brought the action in the area of ​​inflammation and cancer.

Tocotrienols in chemotherapy

A number of studies in recent years has shown that gamma- tocotrienol and delta -tocotrienol could cause an increase in activity of different drugs to chemotherapy ( gemcitabine, erlotinib and gefitinib, doxorubicin, and paclitaxel and others).

Tocotrienols in radioactive radiation and UV radiation

In 2008, 2010 and 2012, it was found that high doses of delta -tocotrienol can exert a significant protective effect against ionizing radiation. Mice were subcutaneously treated with delta-tocotrienol survived an otherwise lethal to 80% load with gamma radiation. Mice that were fed a tocotrienol mixture suffered by UVB light less skin damage (sunburn and tumor development ) than mice that received only alpha- tocopherol.

Further effects

Since 1991, reported further biological functions of tocotrienols, which are mostly not found in tocopherols: These are antiproliferative, neuroprotective, cholesterol-lowering and anti-inflammatory properties. These effects, however, were largely not been demonstrated in humans, but only seen in cell cultures or in animal experiments.

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