Hyperoside hawthorn

In addition to the induction of anthocyanin biosynthesis, chilling stress has also been shown to promote the formation of colorless flavonoids. Cold treatments (and drought stress) caused increases in levels of (—)-epicatechin and hyperoside (quercetin 3-galactoside) in two species of hawthorn, Crataegus laevigata and C. monogyna. Such treatments also enhanced the antioxidant capacity of the shoot extracts, and this may be the primary function of these cold-inducible flavonoids. 

HAWTHORN, Cmtaesi folium cum /lore, fructus. A draft monograph on Hawthorn leaf with flower has been published by the European Pharmacopoeia which defines the drug as the dried whole or cut flower-bearing branches, up to 7 cm long, of Cmtae [us mon iyna Jac., Cmtae ius laevi iata, (Poir.) D.C. (C. oxyacantha, L.) or their hybrids or more rarely other Cmtae ius species. Hawthorn contains not less than 1.5% of flavonoids calculated as hyperoside. 

Lane 1 reference substances with ascending hRf values rutoside, chlorogenic add, hyperoside, lane 2 early golden rod herb DE, lane 3 horsetail herb DE, lane 4 birch leaves DE, lane 5 hawthorn leaves and flowers DE... 

Hawthorn extracts purportedly dilate coronary blood vessels, decrease blood pressure, increase myocardial contractility, and lower serum cholesterol (Anonymous, 1999). Benefits have been demonstrated in heart failure patients (Iwamoto et al., 1981). In patients with Stage II New York Heart Association (NYHA) heart failure, doses of 160-900 mg/d of the aqueous-alcoholic extract for up to 56 d showed an increase in exercise tolerance, decrease in rate/pressure product, and increased ejection fraction (Blumenthal, 1998). The active principles are thought to be flavonoids, including hyperoside, vitexin, vitexin-rhamnose, rutin, and oligomeric procyanidins (dehydrocatechins catechins and/or epicatechins) (Tyler, 1993 Blumenthal, 1997 Blumenthal, 1998 Bigus, 1998). 

Compounds associated with cardiotonic activity include hyperoside, vitexin, vitexin-2 -rhamnoside, oligomeric procyanidins, and (—)-epicatechin. Tbe flavonoids and oligomeric procyanidins have a tonic effect on tbe cardiac muscles, are negatively cbronotropic and dromotropic, and also show tbe bradycar-diac effect commonly noted for Crataegus (list and horhammer)/ Flavonoids may also be the major constituents responsible for the hypolipidemic effect of hawthorn by regulating lipoprotein lipases expression. ... 

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