Overview【1】
Hydroxytyrosol is one of the metabolites of dopamine in animal brains. It is also a polyphenolic compound with strong antioxidant properties in olive oil.
A large number of studies have shown that hydroxytyrosol has good biological effects, including broad-spectrum antimicrobial activity, preventing direct damage from various free radicals and oxidative stress (protein oxidation and DNA damage) induced by ultraviolet rays, preventing The occurrence of diabetes and improving the sensitivity of adipose tissue to insulin, reducing the risk of smoke-induced age-related macular degeneration, reducing the area of atherosclerotic lesions and resisting myocardial ischemia/reperfusion injury, protecting against nitrification stress-induced neurotoxicity and iron ion-induced liver cell damage, improve the symptoms of Alzheimer’s disease induced by β-amyloid (Aβ) and Huntington’s disease induced by 3-nitropropionic acid, prevent and treat osteoporosis, and relieve osteoporosis. Muscle damage caused by excessive exercise, prolongs the temporal lifespan of normal human fibroblasts, inhibits tumor proliferation, etc.
Source
Hydroxytyrosol is a hydrolyzate of oleuropein and is mainly found in virgin olive oil. The measurement results of Owen et al. show that hydroxytyrosol is one of the trace components in virgin olive oil, with a content of approximately 14.4g/kg, which changes with the maturity of the olive fruit and the oil extraction process. Research shows that hydroxytyrosol is also contained in olive fruits, leaves and olive oil extraction waste liquid. The hydroxytyrosol content in olive oil extraction waste liquid is about 1.1225g/L, and the hydroxytyrosol content in olive leaves is about 1.1225g/L. 0.058% ~ 0.768%, which are relatively cheap raw materials for extracting hydroxytyrosol.
Physical and chemical properties【2】
Hydroxytyrosol is a phenolic compound, its chemical name is 3, 4-dihydroxyphenylethyl alcohol, its molecular formula is C 8 H 10 O 3 , its relative molecular weight is 154.16, and it has good fat solubility and water solubility. , easily soluble in water and dimethyl sulfoxide, the solubility in water can reach 5g/100mL, and has a maximum absorption value at 280nm. Hydroxytyrosol uses phenolic hydroxyl groups as hydrogen donors, which can reduce singlet oxygen to less active triplet oxygen and reduce the generation of oxygen free radicals; hydroxytyrosol can react with more active free radicals to generate less active polypeptides. Phenol free radicals interrupt the free radical chain reaction; in addition, the ortho-position phenolic hydroxyl group of hydroxytyrosol can chelate with metal ions to reduce the catalysis of oxidation reactions by metal ions.
Absorption metabolism and tissue distribution【2】
The absorption of hydrophobic phenolic compounds in mammals is dose-dependent. After oral administration of hydroxytyrosol to rats, it enters the small intestinal epithelial cells through passive diffusion, reaches the highest plasma concentration in 5 to 10 minutes, and then decreases quickly. Five minutes after intravenous injection of hydroxytyrosol, it is mainly concentrated in the kidneys, with a concentration about 10 times higher than in the liver, skeletal muscles, and lungs. The excretion method is mainly through the kidneys and urine. Different animals have different absorption rates of hydroxytyrosol. For example, the absorption of hydroxytyrosol in the human body is linear, reaching the highest concentration 32 minutes after ingestion, and the elimination half-life is 2.43 hours.
Hydroxytyrosol can pass through the blood-brain barrier, and it is theoretically speculated that it also has a certain distribution in brain tissue. Since the body itself can synthesize trace amounts of hydroxytyrosol from dopamine as a precursor, the influence of endogenous hydroxytyrosol needs to be considered when detecting the concentration of hydroxytyrosol in brain tissue. In the body’s circulation, hydroxytyrosol exists in low amounts in the free monomeric form and mainly in the glucuronic acid-conjugated form. Although hydroxytyrosol is well absorbed in the body, it has a significant first-pass effect.
Toxicity studies【2】
Rat was given a one-time injection of hydroxytyrosol at a dose of 2g/kg. The rats did not show obvious poisoning or pathological changes in the organs. Only piloerection on the body surface was observed. In a toxicity test using olive pulp extract, it was found that the dose of hydroxytyrosol reached 2.5-3.5g/kg. After feeding mice continuously for 90 days, no obvious poisoning was observed. It is speculated that the toxicity of hydroxytyrosol halfHas potential anti-cancer activity. Hydroxytyrosol inhibits cyclooxygenase-2 (COX-2) and 5-lipoxygenase, and reduces the synthesis of prostaglandin E2, thus inhibiting the occurrence of cancer and other diseases.
In addition, hydroxytyrosol can alter the biosynthesis of eicosanoids in tumors, thereby exhibiting broad-spectrum anticancer activity, inhibiting the proliferation and promoting apoptosis of human tumor cell lines through multiple mechanisms.
References
[1]Luo Cheng, Liu Jiankang. Research progress on the anti-tumor mechanism of hydroxytyrosol[J]. Science China: Life Sciences, 2014, 44(01):14-20.
Amino resin
[2] Zhang Yanqin, Cao Jian. Research progress on the new natural active substance hydroxytyrosol [J]. Journal of Chengdu Medical College, 2016, 11(02): 270-272.
[3] Liu Xiangping, The Preparation and assessment of protection against oxidative stress of the active ingredient from syringa oblata lindl, China Agricultural University Press, 2015.09, pp. 24 pages
