The bioavailability of ergothioneine from mushrooms (Agaricus bisporus) and the acute effects on antioxidant capacity and biomarkers of inflammation

Background: Ergothioneine (ET) is a sulfur containing amino acid that functions as an antioxidant. Mushrooms are a primary source of ET containing from 0.4 to 2.0. mg/g (dry-weight). The bioavailability of ET from mushrooms in humans remains unclear. Objective: We evaluated the bioavailability of ET in healthy men (n = 10) in a pilot study, using a randomized, cross-over, dose-response, postprandial time-course design, conducted at the General Clinical Research Center at Pennsylvania State University in 2009. Method: ET was administered through a mushroom test meal containing 8g and 16g of mushroom powder. Postprandial red blood cell concentrations of ET were measured. Plasma glucose, triglycerides, HDL, LDL and total cholesterol also were monitored. Biomarkers of inflammation and oxidative stress were evaluated using C-reactive protein and ORAC _total. Results: ET was bioavailable after consuming mushrooms and a trend in the postprandial triglyceride response indicated that there was a blunting effect after both the 8g and 16g ET doses were compared with the 0g dose. Despite ET's antioxidant properties, ORAC _total values decreased after the 8g and 16g mushroom meal. Conclusions: Ergothioneine from A. bisporus mushrooms is bioavailable as assessed by red blood cell uptake postprandially, and consumption is associated with an attenuated postprandial TG response.