Robert B. Beelman

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 2.0mg/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 8 g and 16 g 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 8 g and 16 g ET doses were compared with the 0 g dose. Despite ETs antioxidant properties, ORAC(total) values decreased after the 8 g and 16 g 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.

Selenium-enriched Agaricus bisporus mushrooms suppress 7,12-dimethlybenz[a]anthracene bioactivation in mammary tissue.

The present studies compared dietary Se (1.0 microg/g) when provided as either fortified Agaricus bisporus mushrooms, or sodium selenite on the in vivo metabolism of 7,12-dimethylbenz(a)anthracene (DMBA). Dietary addition of Se unenriched A. bisporus mushrooms at 2% did not alter the occurrence of DMBA induced DNA adducts or the activity of glutathione S-transferase (GST). However, the addition of Se as enriched mushrooms, or as selenite, significantly increased both liver and mammary GST activity. Providing sodium selenite, or enriched mushrooms also significantly reduced total and anti-3,4-dihydrodiol-1,2-epoxide-deoxyguanosine adducts compared to feeding the basal diet (P < 0.05). These investigations provide evidence that Se enriched mushrooms can be used as an effective method to retard chemically induced tumors.

Changes in soluble sugars in various tissues of cultivated mushrooms,Agaricus bisporus, during postharvest storage*

Abstract Soluble sugar contents in various tissues of two hybrid strains (U1 and U3) of cultivated mushrooms, Agaricus bisporus , were determined during 10 days of storage at 12°C. No significant differences in mannitol, trehalose and ribose contents were observed between these two hybrid strains at harvest. Mannitol content decreased in the cap and lower stipe throughout the storage period, while it remained steady in gills and increased slightly in upper stipes. No significant changes in trehalose contents were observed. Ribose was continuously accumulated in all tissues of the two hybrid strains during postharvest storage.

Effects of Postharvest Pulsed UV Light Treatment of White Button Mushrooms (Agaricus bisporus) on Vitamin D2 Content and Quality Attributes

Pulsed UV light (PUV) was investigated as a means to rapidly increase vitamin D(2) (D(2)) content in fresh button mushrooms (Agaricus bisporus). D(2) was found to increase to over 100% RDA/serving following 3 pulses (1 s). Following 12 pulses, D(2) began to approach a maximum concentration of 27 μg/g DW. The D(2) produced with 3 pulses decreased from 11.9 to 9.05 μg/g DW after 3 days of storage; however, D(2) levels remained nearly constant after this point throughout an 11-day shelf life study. PUV treated sliced mushrooms produced significantly more D(2) than whole mushrooms, and it was also observed that brown buttons generated significantly less D(2) than white buttons. Several quality attributes were assessed, and no significant differences between control and PUV treated mushrooms were observed. These findings suggest that PUV treatment is a viable method for rapidly increasing the D(2) content of fresh mushrooms without adversely affecting quality parameters.

The Cancer Preventive Effects of Edible Mushrooms

An increasing body of scientific literature suggests that dietary components may exert cancer preventive effects. Tea, soy, cruciferous vegetables and other foods have been investigated for their cancer preventive potential. Some non-edible mushrooms like Reishi (Ganoderma lucidum) have a history use, both alone and in conjunction with standard therapies, for the treatment of various diseases including cancer in some cultures. They have shown efficacy in a number of scientific studies. By comparison, the potential cancer preventive effects of edible mushrooms have been less well-studied. With similar content of putative effective anticancer compounds such as polysaccharides, proteoglycans, steroids, etc., one might predict that edible mushrooms would also demonstrate anticancer and cancer preventive activity. In this review, available data for five commonly-consumed edible mushrooms: button mushrooms (Agaricus bisporus), A. blazei, oyster mushrooms (Pleurotus ostreatus), shiitake mushrooms (Lentinus edodes), and maitake (Grifola frondosa) mushrooms is discussed. The results of animal model and human intervention studies, as well as supporting in vitro mechanistic studies are critically evaluated. Weaknesses in the current data and topics for future work are highlighted.

Evaluation and Bacterial Populations Associated with Fresh Mushrooms (Agaricus Bisporus)

Abstract Doores, Stephanie, Kramer, Michael, and Beelman, Robert. 1986. Evaluation of bacterial populations associated with fresh mushrooms ( Agaricus bisporus ) Proc. Int. Symp. Tech Aspects Cult. Edible Fungi Total aerobic bacterial counts on mushrooms were determined for the first six flushes of the crop cycle and the casing material and water were sampled at selected intervals. Total bacterial numbers ranged from 2. 1 to 16 × 10 6 CFU/g; numbers were relatively constant through the fifth flush of the crop cycle and decreased slightly by flush 6. Counts from casing material were considerably higher, between 1. 7 and 2. 9 × 10 8 CFU/g and also were relatively constant over the cycle. Bacterial counts from tap water were lower and did not appear to contribute to overall microbial populations. The majority (54. 0%) of bacteria isolated from the individual flushes were identified as fluorescent pseudomonads with flavobacteria comprising the second largest group (10. 0%). The proportions of these two organisms remained relatively constant; however, the pseudomonads decreased between the fifth and sixth flush while the flavobacteria increased. Bacterial populations during postharvest storage at 13°C increased from an initial load of 10 7 CFU/g to almost 10 11 CFU/g. The same two groups predominated but the proportion of flavobacteria increased during later storage. A third group of pseudomonads having mucoidal colonies appeared during storage in a biphasic manner. Deterioration of mushroom quality as indicated by maturity and color measurement appeared concomitant with bacterial growth indicating that darkening is related to increased bacterial numbers. However, phytopathogenic strains of microorganisms responsible for blotch occurred in very low numbers during storage.

Mushrooms and Health Summit Proceedings

The Mushroom Council convened the Mushrooms and Health Summit in Washington, DC, on 9-10 September 2013. The proceedings are synthesized in this article. Although mushrooms have long been regarded as health-promoting foods, research specific to their role in a healthful diet and in health promotion has advanced in the past decade. The earliest mushroom cultivation was documented in China, which remains among the top global mushroom producers, along with the United States, Italy, The Netherlands, and Poland. Although considered a vegetable in dietary advice, mushrooms are fungi, set apart by vitamin B-12 in very low quantity but in the same form found in meat, ergosterol converted with UV light to vitamin D2, and conjugated linoleic acid. Mushrooms are a rare source of ergothioneine as well as selenium, fiber, and several other vitamins and minerals. Some preclinical and clinical studies suggest impacts of mushrooms on cognition, weight management, oral health, and cancer risk. Preliminary evidence suggests that mushrooms may support healthy immune and inflammatory responses through interaction with the gut microbiota, enhancing development of adaptive immunity, and improved immune cell functionality. In addition to imparting direct nutritional and health benefits, analysis of U.S. food intake survey data reveals that mushrooms are associated with higher dietary quality. Also, early sensory research suggests that mushrooms blended with meats and lower sodium dishes are well liked and may help to reduce intakes of red meat and salt without compromising taste. As research progresses on the specific health effects of mushrooms, there is a need for effective communication efforts to leverage mushrooms to improve overall dietary quality.

Effect of 10-oxo-trans-8-decenoic acid on growth of Agaricus bisporus

Abstract 10-Oxo- trans -8-decenoic acid (ODA) was found to stimulate mycelial growth and stipe elongation in Agaricus bisporus . Higher mushroom yield at the first flush resulting from supplementation of the casing layer with ODA in the form of mushroom powder suggested that ODA may be involved in the initiation of fruiting.

Antifungal Activity of 10-Oxo-trans-8-decenoic Acid and 1-Octen-3-ol against Penicillium expansum in Potato Dextrose Agar Medium

In mushrooms, 10-oxo-trans-8-decenoic acid (ODA) and 1-octen-3-ol are secondary metabolites produced naturally by the enzymatic breakdown of linoleic acid. Both compounds were determined to inhibit the mycelial growth of Penicillium expansum PP497A, a common food spoilage organism, when added to potato dextrose agar medium. ODA and 1-octen-3-ol were inhibitory at concentrations of > 1.25 mM (230 microg/g for ODA and 160 microg/g for 1-octen-3-ol). At pH 5.6, 1-octen-3-ol was more inhibitory than ODA. However, at pH 3.5, both compounds (especially ODA) were more inhibitory than they were at pH 5.6. This finding indicates that the undissociated carboxyl of ODA was important for inhibition. At a concentration of 2.5 mM and a pH of 3.5, ODA and 1-octen-3-ol inhibited growth by 43.1 and 41.9%, respectively. An additive effect was observed when both compounds were added at a combined concentration of > or = 1.25 mM; when both were added at a combined concentration of 2.5 mM, mycelial growth was inhibited by 48.8 and 72.8% at pHs of 5.6 and 3.5, respectively. Although the antifungal activity levels for these two compounds were lower than those observed for equal molar concentrations of sorbate, a common antifungal compound, these findings indicate that further investigation of the potential of ODA and 1-octen-3-ol for use as natural food preservatives is warranted.

Inducing malolactic fermentation in wines

Malolactic fermentation (MLF) in wine can be accomplished by relying on the natural microflora or by inducing through inoculation of a specific strain(s) of malolactic bacteria, primarily strains of Leuconostoc oenos. Problems with inducing MLF include intrinsic factors of the grape must such as pH, presence of sulfur dioxide, and ethanol in addition to antagonism of malolactic bacteria by wine yeast. Current methods and new technology to improve the predictability of MLF are discussed.