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Herein, a supercritical extraction plant (with a 6 L extraction cell) was successfully used to obtain ergosterol-enriched extracts from Lentinula edodes under the following conditions: a temperature of 40 °C, pressure of 225 bar, reaction time of 1-5 h, and the flow rate of 20 L h -1 for recirculated CO 2 . Moreover, ergosterol (ERG) and the SFE extract (SFE) with highest ergosterol concentration were microemulsified and submitted to in vitro digestion to study their ability to displace cholesterol from dietary mixed micelles (DMMs). ERG was also mixed with a β-glucan-enriched (33.5%) extract (BGE) obtained from L. edodes to investigate the synergies between them; the results indicated that all these extracts (including BGE without ERG) could reduce the cholesterol levels in the DMMs. However, when ERG and SFE were simultaneously administered to mice with a hypercholesterolemic diet, no significant differences in the serum cholesterol levels were detected as compared to the case of the control. However, when only BGE was administrated to another mice model previously induced with hypercholesterolemia, significant reduction in the cholesterol levels was noticed.

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.

An optimized PLE method was applied to several truffle species using three different solvent mixtures to obtain bioactive enriched fractions. The pressurized water extracts contained mainly (1 → 3),(1 → 6)-β-D-glucans, chitins, and heteropolymers with galactose and mannose in their structures. The ethanol extracts included fatty acids and fungal sterols and others such as brassicasterol and stigmasterol, depending on the species. They also showed a different fatty acid lipid profile depending on the solvent utilized and species considered. Ethanol:water extracts showed interesting lipids and many phenolic compounds; however, no synergic extraction of compounds was noticed. Some of the truffle extracts were able to inhibit enzymes related to type 2 diabetes; pressurized water extracts mainly inhibited the α-amylase enzyme, while ethanolic extracts were more able to inhibit α-glucosidase. Tuber brumale var. moschatum and T. aestivum var. uncinatum extracts showed an IC50 of 29.22 mg/mL towards α-amylase and 7.93 mg/mL towards α-glucosidase. Thus, use of the PLE method allows o bioactive enriched fractions to be obtained from truffles with antidiabetic properties. [ABSTRACT FROM AUTHOR]

Ergosterol-enriched extracts obtained from Agaricus bisporus were incorporated into lard, butter and white chocolate as food carriers to study their potential as ingredients with hypocholesterolemic properties to design functional foods. Lard was selected and supplemented with several concentrations of cholesterol and ergosterol, beta-sitosterol (as control) and two types of ergosterol-enriched extracts obtained by supercritical fluid extraction (SFE) and accelerated solvent extraction (ASE). The prepared food combinations were submitted to a specific in vitro digestion model, their dietary mixed micelle (DMM) fractions isolated and administrated to Caco2 cell cultures. Ergosterol was as effective as some phytosterols such as sitosterol, in the displacement of cholesterol from the DMMs when applied to the food matrix in a ratio (1:2, w/w, cholesterol:sterol). The ASE extract was not effective but addition of the SFE extract provoked a 67% reduction in the DMM cholesterol content. Lard supplementation with fungal beta-glucans able to bind bile-acids enhanced the cholesterol displacement from the DMMs induced by the sterols although it also reduced ergosterol incorporation. Fungal sterols also impaired proper cholesterol transport through Caco2 monolayers. [ABSTRACT FROM AUTHOR]

The combination of supercritical fluid extraction followed by UV-irradiation resulted in an interesting strategy to obtain ergosterol- and Vitamin D 2 -enriched extracts from Lentinula edodes to design novel functional food. Extractions carried out following a specific experimental design pointed out that extraction yields and ergosterol concentrations were more influenced by pressure than by the extraction temperature although, high temperatures (55–75 °C) might induce transformation of ergosta-7,22-dienol and fungisterol into ergosterol. After extraction, the ergosterol-enriched extracts should be dissolved in methanol or ethanol and irradiated (25 °C, 4 cm) to partially transform ergosterol into vitamin D 2 . Irradiation at 365 nm was less effective than at 254 nm. The fastest transformation was obtained using a UV lamp covering the complete UV spectrum for a maximum of 1 h. However, this lamp also induced vitamin D 4 formation although in lower amounts than vitamin D 2 or lumisterol 2 while with irradiation at 254 nm most of ergosterol was transformed into vitamin D 2 . [ABSTRACT FROM AUTHOR]

Ergosterol, ergosta7,22 dienol, ergosta 5,7 dienol, fungisterol, ergosta-4,7,2-trien-3-ona and ergosta-4,6,8(14),22-tetraen-3-ona were the fungal sterols detected in Agaricus bisporus mushrooms after optimization of a sterol extraction method. Their concentration ranged from 3.1 to 11.2mg/g dw depending on the strain, casing soil, flush number, developmental stage and sporophore tissue analyzed. Two methods were optimized to obtain sterol enriched extracts from A. bisporus fruiting bodies using pressurized liquid extraction (PLE) and supercritical fluid extraction (SFE). PLE using ethanol as solvent at 10.7MPa (50°C and 100°C) after 5cycles of 5min extraction (mixing in the extraction cell the sample with sand in a ratio 1:4) yielded extracts with respectively 5 and 2.9% sterols. Using SFE-CO2 at 40°C and 9 to 30MPa fractions containing 60% of sterols were obtained. Both technologies could be also utilized to extract sterols from mushroom by-products (the lower part of the stipe) as a method for their valorization. Industrial relevance: In this work, two environmentally friendly methods (SFE and PLE) to obtain sterol enriched fractions from Agaricus bisporus mushrooms were optimized. Extractions from both the complete fruiting body and the lower part of the stipe (usually discarded as a by-product during harvesting) yielded extracts with high ergosterol (and derivatives) content that could be used as functional ingredients to design novel foods with hypocholesterolemic properties since fungal sterols are able to reduce cholesterol levels in serum as plant phytosterols. Moreover, if the mushroom by-products are utilized as starting material, this application can be an interesting alternative method for the commercial valorization of this residue. [ABSTRACT FROM AUTHOR]

• Tuber melanosporum is a potential source of bioactive compounds. • PLE (16.7 MPa, 180 °C, 30 min) can extract polysaccharides and fungal sterols. • (1 → 3)-β-glucans and heteropolymers were identified in truffles. • Extracted polysaccharides reduced pro-inflammatory cytokines secretion. Truffles, besides the appreciated aromatic compounds, contain other molecules with interesting bioactive properties. A screening of fungal sterols and β-glucans within different truffle species and locations was carried out. These compounds were extracted with pressurized liquids (PLE) generating enriched fractions. Extraction efficiency was studied with a full-factorial experimental design (Response surface methodology, RSM), using water and ethanol as extraction solvents. Polysaccharides from truffle powder (TP) and the optimal PLE extract (EP) obtained were precipitated and analysed by NMR and GC–MS. THP-1 cell cultures were utilized to test immunomodulatory properties. With the optimal PLE conditions (16.7 MPa, 180 °C, 30 min) 64 and 22.5% yields were obtained respect, with water and ethanol, generating fractions containing respect, 9.1% β-glucan and 4.5% ergosterol. NMR analyses detected (1 → 3)-β-glucan structures in truffle. The EP induced a reduction of 40% IL-1β and 60% IL-6 pro-inflammatory cytokines secretion suggesting potential immunomodulatory activity. [ABSTRACT FROM AUTHOR]