%0 Journal Article
%T NMR evaluation of total statin content and HMG-CoA reductase inhibition in red yeast rice (Monascus spp.) food supplements
%A Dirk W Lachenmeier
%A Yulia B Monakhova
%A Thomas Kuballa
%A Sigrid L£¿bell-Behrends
%A Sibylle Maixner
%A Matthias Kohl-Himmelseher
%A Asja Waldner
%A Christian Steffen
%J Chinese Medicine
%D 2012
%I BioMed Central
%R 10.1186/1749-8546-7-8
%X The total statin content was determined by a 400 MHz 1H NMR spectroscopic method, based on the integration of the multiplet at ¦Ä 5.37-5.32 ppm of a hydrogen at the hexahydronaphthalene moiety in comparison to an external calibration with lovastatin. The activity of HMG-CoA reductase was measured by a commercial spectrophotometric assay kit.The NMR detection limit for total statins was 6 mg/L (equivalent to 0.3 mg/capsule, if two capsules are dissolved in 50 mL ethanol). The relative standard deviations were consistently lower than 11%. The total statin concentrations of five red yeast rice supplements were between 1.5 and 25.2 mg per specified daily dose. A dose-dependent inhibition of the HMG-CoA reductase enzyme activity by the red yeast rice products was demonstrated.A simple and direct NMR assay was developed to determine the total statin content in red yeast rice. The assay can be applied for the determination of statin content for the regulatory control of red yeast rice products.The fermentation products of Monascus, have been used as food and traditional Chinese medicine for over 1000 years [1]. The products are called "Hong Qu", "Hon-Chi", "Anka" or "Ang-kak" in China and Taiwan, "Beni Koji" or "red Koji" in Japan. In Europe, the products are called "red yeast rice", "red rice", "red mould rice" or "red Chinese rice". It should be noted that the designation "yeast" is taxonomically not correct [1]. Red yeast rice is used as an additive for the colouring, flavouring and preservation of foods, which may be permitted in some Asian countries but not in Europe. Currently red yeast rice products are predominantly marketed as food supplements, primarily sold through the Internet [2].Monacolin compounds are formed by Monascus during the fermentation process. They cause a reversible competitive inhibition of the microsomal hydroxymethyl-glutaryl coenzyme A (HMG-CoA) reductase; thus, they prevent the reduction of HMG-CoA to mevalonic acid and the formation of cholest
%U http://www.cmjournal.org/content/7/1/8