ARS | Publication request: Vitamin D and sterol composition of ten types of mushrooms from retail suppliers in the United States

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 13, 2011
Publication Date: June 13, 2011
Citation: Phillips, K.M., Ruggio, D.M., Horst, R.L., Minor, B., Simon, R., Feeney, M., Byrdwell, W.C., Haytowitz, D.B. 2011. Vitamin D and sterol composition of ten types of mushrooms from retail suppliers in the United States. Journal of Agricultural and Food Chemistry. 59(14):7841-7853.

Interpretive Summary: Vitamin D has been well established as critical for bone health, and more recently its potential role in immune function, prevention of some types of cancer, and in other diseases has received increasing attention. Vitamin D in foods occurs naturally primarily in animal products. Milk, fortified cereals, and an increasing number of other foods, including juices, processed cheese, yogurt, margarine, and ice cream, are fortified with vitamin D. Mushrooms are probably the richest natural non-animal food source of vitamin D, which occurs as vitamin D2. Analogous to the photochemical reactions taking place in skin exposed to sunlight, where exposure to ultra-violet (UV) light converts 7-dehydrocholesterol (7-DHC) to vitamin D3, in mushrooms vitamin D2 is produced from ergosterol present on the surface of the mushroom upon exposure to sunlight or other sources of UV light. Recently, some mushroom producers have taken advantage of this fact and have produced vitamin D-enhanced mushrooms by processing with intentional exposure to UV light; these mushrooms are now available in some U.S. retail markets. The content of vitamin D in mushrooms can vary due to conditions of UV exposure, and to loss of vitamin D over time in UV-exposed mushrooms. The vitamin D content of different types of mushrooms in the U.S. retail market had not been determined prior to this work. To provide vitamin D and sterol composition data for the USDA National Nutrient Database for Standard Reference (SR), ten types of mushrooms, including commercially produced UV-treated portabella, were sampled as part of the National Food and Nutrient Analysis Program (NFNAP) in cooperation with the Mushroom Council (San Jose, CA) and analyzed for vitamin D2, ergosterol and ergosterol metabolites, and phytosterols. Sterols were analyzed by GC-FID with mass spectrometric confirmation of components. Vitamin D was assayed using HPLC with a [3H]-vitamin D3 internal standard. Ergosterol was highest in shiitake and maitake (mean, 79-85 mg/100g) and lowest in morel and enoki (26-36 mg/100g); the range was <10 mg/100g among white button composites but 20-50 mg/100g for samples of other types. Only morel contained brassicasterol (28-29 mg/100g) and campesterol (<1-5.7 mg/100g). Vitamin D was low (0.1-0.3 µg/100g) in Agaricus bisporus (white button, crimini, portabella) and enoki, moderate in shiitake and oyster (0.5-0.9 µg/100g), and high in morel, chanterelle, maitake (5.3-29.5 µg/100g), and UV-treated portabella (3.4-20.9 µg/100g), with significant variability among composites for some types. A unique finding was the presence of another vitamer, possibly D4, which would be the product of UV irradiation of ergosta-5,7-dienol that is present in mushrooms. The level of this vitamer was correlated with the D2 concentration and was highest in the UV-treated mushrooms (up to up to 35.4 µg/100g). Further work is underway to identify this component. SR is the primary source of U.S. food composition data for estimation of nutrient intake from food consumption data, and the vitamin D data from this study were incorporated in Release 22 of SR (USDA, 2009). These values will be added to the Food and Nutrient Dataset for Dietary Surveys, used in the What We Eat in America component of National Health and Nutrition Examination Survey (USDA, 2010), facilitating research requiring knowledge of the vitamin D content of the U.S. diet.

Technical Abstract: Vitamin D, ergosterol, ergosterol metabolites, and phytosterols were analyzed in ten mushroom types sampled nationwide in the U.S. to update the USDA Nutrient Database for Standard Reference. Sterols were analyzed by GC-FID with mass spectrometric confirmation of components. Vitamin D was assayed using HPLC with a [3H]-vitamin D3 internal standard. Ergosterol was highest in shiitake and maitake (mean, 79-85 mg/100g) and lowest in morel and enoki (26-36 mg/100g); the range was <10 mg/100g among white button composites but 20-50 mg/100g for samples of other types. Only morel contained brassicasterol (28-29 mg/100g) and campesterol (<1-5.7 mg/100g). Vitamin D was low (0.1-0.3 µg/100g) in Agaricus bisporus (white button, crimini, portabella) and enoki, moderate in shiitake and oyster (0.5-0.9 µg/100g), and high in morel, chanterelle, maitake (5.3-29.5 µg/100g), and UV-treated portabella (3.4-20.9 µg/100g), with significant variability among composites for some types. Samples high in D2 contained another vitamer, possibly D4, up to 35.4 µg/100g.