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White-button (Agaricus bisporus) and shiitake (Lentinula edodes) mushrooms are widely consumed worldwide because of their organoleptic properties but also their bioactive compounds such as β-glucans, ergosterol, and phenolic compounds. Although these mushrooms can be eaten as raw food, they are usually subjected to household cooking treatments, so their effect on the stability of these molecules was evaluated in this work. The results showed that frying reduced β-glucan and ergosterol content but protected mushrooms from the loss of phenolic compounds that were mainly affected by boiling, being this procedure able to increase β-glucans and ergosterol concentrations. It can be concluded that culinary treatments had differential effects depending on the specific molecule, so they should be applied or avoided considering the target compound. Moreover, further research is encouraged to fully understand the mechanisms involved in the content variations and the impact on the biological activity of these mushrooms. [ABSTRACT FROM AUTHOR]

Shiitake mushrooms (Lentinula edodes) contain compounds with hypocholesterolemic and immune-modulatory activities such as ergosterol and chitin that can be partially transformed into vitamin D and chitosan to yield extracts with enhanced bioactivities. A method was optimized to increase vitamin D2 levels by irradiating a non-soluble fraction obtained from shiitake mushrooms during 1 h with UV-light (254 nm) at 50 °C in methanol. After 1 h, almost all of the ergosterol was transformed into vitamin D2. The conversion ratio can be simply adjusted by reducing the irradiation time. A deacetylation treatment with 50% NaOH for 24 h at 95 °C was needed to generate chitosan and other water-soluble lower molecular weight derivatives from chitin. To obtain an extract enriched in both compounds, the defined methods can be combined, but the extracts should be firstly deacetylated and later irradiated. In this order, an extract is obtained containing vitamin D2 (4.65 mg/g) and chitosan (2.83%). [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the hypocholesterolemic, immune- and microbiota-modulatory effect of a mushroom extract in hypercholesterolemic subjects. Methods: A randomized, controlled, double-blind, and parallel clinical trial was carried out with subjects from 18 to 65 years old (n = 52) with untreated mild hypercholesterolemia. Volunteers consumed a β-d-glucan-enriched (BGE) mixture (10.4 g/day) obtained from shiitake mushrooms (Lentinula edodes) ensuring a 3.5 g/day of fungal β-d-glucans or a placebo incorporated in three different commercial creams. Results: This mixture showed hypocholesterolemic activities in vitro and in animal studies. After eight weeks intervention, no significant differences in lipid- or cholesterol-related parameters were found compared to placebo subjects as well as before and after the BGE mixture administration. No inflammatory or immunomodulatory responses were noticed and no changes in IL-1β, IL-6, TNF-α or oxLDL were recorded. However, consumption of the BGE mixture was safe and managed to achieve the dietary fibre intake recommended as cardiovascular protective diet. Moreover, the BGE mixture modulated the colonic microbiota differently compared to placebo. Microbial community composition varied from before to after the intervention with several genera being positively or negatively correlated with some biomarkers related to cholesterol metabolism. Conclusion: These results suggested a relation between cholesterol metabolism, microbiota and BGE administration. Nevertheless, the precise significance of this differential modulation was not fully elucidated and requires further studies. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of two extracts obtained from Agaricus bisporus on the mRNA expression of cholesterol-related genes. One of the extracts contained ergosterol and other fungal sterols (SFE) and the other contained β-glucans and fungal sterols (EβG). Methods: Firstly, the dietary mixed micelles (DMMs) generated after in vitro digestion of standards and SFE were applied to Caco2 cells. Then, the lower compartment after a Caco2-transport experiment was applied to HepG2 cells. The mRNA expression was assessed in both cell lines by low-density arrays (LDA). Mice received the extracts, ergosterol or control drugs after 4 weeks of a high-cholesterol diet. The lipid profile of plasma, liver and feces was determined. LDA assays were performed in liver and intestines. Results: The DMM fraction of SFE up-regulated the LDLR mRNA expression in Caco2 cells. The lower compartment after Caco2-transport experiments up-regulated LDLR and modulated several other lipid-related genes in HepG2 cells. In mice, SFE decreased TC/HDL ratio and reduced hepatic triglycerides paralleled with down-regulation of Dgat1 expression, while EβG did it without transcriptional changes. Addition of SFE or ergosterol induced in jejunum a similar transcriptional response to simvastatin and ezetimibe; they all down-regulated Srebf2 and Nr1h4 (FXR) genes. Conclusion: Ergosterol-containing extracts from A. bisporus lowered hepatic triglyceride and modify the mRNA expression of cholesterol-related genes although the transcriptional regulation was unrelated to changes in plasma lipid profile. These extracts may be useful limiting hepatic steatosis and as bioactive ingredients to design novel functional foods preventing lifestyle-related diseases such as non-alcoholic fatty liver disease. [ABSTRACT FROM AUTHOR]