Proceedings of the 7 th International Conference on Mushroom Biology and Mushroom Products (ICMBMP7) 2011 EDIBLE MUSHROOMS AS POTENTIAL SOURCES OF NEW HYPOCHOLESTEROLEMIC COMPOUNDS ALICIA GIL-RAMIREZ 1 , CRISTINA CLAVIJO 2 , MARIMUTHU PALANISAMY 1 , CRISTINA SOLER-RIVAS 1 , ALEJANDRO RUIZ-RODRIGUEZ 1 , FRANCISCO R. MARÍN 1 , GUILLERMO REGLERO 1 , MARGARITA PÉREZ 2 1 Department of Production and Characterization of New Foods. CIAL -Research Institute in Food Science (UAM+CSIC). Madrid. Spain. 2 Centro Tecnológico de Investigación del Champiñón de La Rioja (CTICH). Autol. Spain cristina.soler@uam.es ABSTRACT Coronary heart disease (CHD) is the leading cause of death in the Western world after cancer according to World Health Organization. Many studies have established that high total- cholesterol levels and low-density lipoprotein (LDL) cholesterol levels are risk factors for CHD and mortality. Many investigations have been carried out to explore the possibility of increasing components which have hypocholesterolemic effects in the diet. Two particular groups of substances phytosterols and β-glucans gained much attention in the last decade and there are already commercialized functional food products supplemented with plant sterols and/or derivatives (sterol-esters, stanols, etc) and specific polysaccharides mainly obtained from cereals which are able to inhibit the absorption of exogenous cholesterol. Edible mushrooms are good sources of phytosterol-like structures such as ergosterol, fungisterol and other derivatives since they were present in all mushrooms because they are constitutive compounds of the hyphae membranes. On the other hand, edible mushrooms contained polysaccharides and depending on the specie, they showed high levels of β-glucans. Apart from these compounds, some mushroom species included certain molecules that were different than lovastatin (since statins were not detected) able to impair the synthesis of endogenous cholesterol by inhibiting the HMGCoA reductase (3-hydroxy-3-methyl-glutaryl CoA reductase) the key enzyme in the cholesterol metabolism. Keywords: cholesterol, statins, glucans, sterols, HMGCoA reductase INTRODUCTION Maintenance of cholesterol homeostasis is one of the major issues in the human body since it is a key constituent of the cell membranes. Thus, if the molecule is not obtained from diet liver synthesizes it by a specific metabolic pathway. When cholesterol enters the lumen of the small intestine it is coming from 3 different sources: diet, bile and intestinal epithelial sloughing. Nowadays in industrialized countries, the average daily intake is approximately 300 – 500 mg. Bile provides 800 mg – 1200 mg cholesterol per day to the intraluminal pool. The turnover of intestinal mucosal epithelium is approximately 300 mg cholesterol per day. The synthesized cholesterol can reach ca. 1000-1600 mg per day. When an excess of exogenous cholesterol is absorbed and reach the liver, it induces several regulation effects such as inhibition of cholesterol biosynthetic pathway and of the LDL-R (low density lipoproteins-receptor) gene expression [1, 2]. Section Posters 110