Other Research on Nutrients in Mushrooms

Other Research on Nutrients in Mushrooms:
Selenium, B Vitamins, Potassium, Vitamin D, Carbohydrates,
Weight Control & Antioxidant Activity

Click here to learn about and order our new Health Products

Selenium
Selenium, an essential trace mineral, functions largely through its association with proteins, known as selenoproteins. Several selenoproteins defend against oxidative stress. The selenium content of food depends upon the selenium content of the soil in which the plant or animal food source was grown or raised.

Mushrooms accumulate selenium based on the soil content, with levels highest in those grown in the Midwest (Beelman). Mushrooms provide more selenium than other foods in the produce category and can be a source of this essential mineral for vegetarians. According to the Mushroom Council’s Nutrition Labeling Toolkit for Mushrooms (2002), white, brown and Portabella mushrooms are a “good” source of selenium, providing 10 percent of the Daily Value (70 micrograms) per serving (84-85 g). The Institute of Medicine’s Food and Nutrition Board in 2000 set the selenium Recommended Dietary Allowance (RDA) at 55 micrograms (mcg) day for both men and women. A serving of mushrooms has the potential to contribute significantly to the 55 mcg RDA for selenium although 70 mcg remains the Daily Value for labeling purposes. According to the National Health and Examination Survey, 1999-2000 for the U.S. population, the mean dietary intake of selenium for all ages and both genders is estimated to be 103 mcg – almost twice the RDA (Ervin).
[TOP]

Consumer awareness
The Council conducted market research to determine selenium awareness among consumers and whether information about selenium’s benefits motivates consumers to purchase mushrooms. According to research conducted by telephone in 2000 (Herrmann), a majority – 55 percent – claimed to have heard of selenium prior to the survey. Of these “selenium aware” respondents, 43 percent considered selenium to be nutritionally important. Consumers who were both aware of selenium and considered it important represented less than one-quarter of the survey respondents. The report suggested focusing on the selenium aware group. Although a niche market, the selenium-aware group had identifiable demographics, which could make them easier to reach.
Consumer research in 2004 determined the impact selenium claims on product labels might have to motivate consumers to buy fresh mushrooms (Stanton). In the overall sample, 37 percent of the respondents claimed some knowledge of selenium, which is lower than their awareness of some other less common nutrients (43 percent awareness of lycopene) and considerably lower than awareness of more common nutrients such as vitamin C (97 percent awareness level). However, of those that claim to be somewhat or very nutritionally aware, 84 percent claimed to be aware of selenium.
For the approximately one-third of the overall sample claiming knowledge of selenium, several sample product claims on selenium’s benefits had broad appeal. However, the population in general appears not interested in selenium. According to this purchase trigger research, inclusion of a selenium claim on a product may in fact be unfavorable for the general population, although such claims could be effective in targeted stores where selenium aware shoppers frequent.
[TOP]

Anticancer Activity
Selenium has received increasing attention as a possible cancer preventive trace mineral possibly through antioxidant protection and/or increased immune function. The anticancer activity of selenium has been shown in laboratory animals and cell lines. There is evidence from human studies to suggest that selenium may reduce the incidence of cancer when taken in higher doses than most diets provide – 200 micrograms a day usually as selenium yeast supplements.

Epidemiological studies suggest an inverse relationship between selenium intake and the incidence of certain cancers. Blood or plasma levels of selenium often are lower in patients with cancer than those without, but results of research based on toenail selenium values and the incidence of cancer have been inconsistent (Whanger). Nail clippings are thought to reflect nutritional status for up to a year prior to clipping and thus be an indication of long-term selenium intake compared to blood levels.
An update on the relationship of selenium to cancer (Whanger) and a thorough review of current literature on selenium and prostate cancer describing ongoing clinical trials and preclinical mechanistic studies of different forms of selenium have been published (Meuillet).
[TOP]

Prostate Cancer
A statistically significant inverse association between pre-diagnostic plasma selenium levels and subsequent risk of advanced prostate cancer was observed among men enrolled in the Physician’s Health Study (Li). Among men with increased PSA levels at baseline, higher levels of plasma selenium were associated with a reduced risk of all prostate cancer. This research suggests that selenium may affect tumor growth rather than premalignancy development (Taylor).

The Netherlands Cohort Study observed an inverse association between toenail selenium level and prostate cancer risk
(van den Brandt). However, in a case-controlled study among British men, fingernail selenium concentration was not significantly associated with prostate cancer risk. Selenium concentration was not associated with localized or advanced disease although men in the highest quartile of selenium nail concentration had a non-significant reduced risk of developing advanced prostate cancer compared to men in the lowest selenium quartile (Allen). Another study compared toenail selenium levels of Austrian men with prostate cancer with that of controls and found that selenium levels did not differ significantly (Lipsky). The nail selenium concentration in both British and Austrian men is lower than that of typical North American populations. Lipsky observes that body selenium levels may not influence prostate cancer incidence noting that toenail selenium levels in North America are twice as high in the Austrian study, yet prostate cancer incidence in North America is greater than in Europe.

Given these and other important findings on selenium and prostate cancer risk, the National Cancer Institute has launched a randomized, double-blind, placebo-controlled prevention trial involving 32,000 men at 400 sites to compare the effect of selenium and vitamin E (SELECT, the Selenium and Vitamin E Cancer Prevention Trial) administered alone versus in combination on the clinical incidence of prostate cancer. The results of the SELECT Trial are years away (2013); recruitment began in 2001 and each man’s participation in the trial will last from 7 to 12 years.
[TOP]

Colorectal Cancer
Limited epidemiology published on the association between selenium and colorectal cancer has been mixed, inconclusive and based on small studies (Duffield-Lillico). However, by pooling study populations of large trials, researchers are able to analyze the effect of selenium on specific cancer endpoints with greater accuracy than in individual studies by themselves. A combined analysis of data from three completed clinical trials which tested the effects of various nutritional interventions (wheat bran fiber, low-fat, high-fiber diet or supplementation of vitamin C, E or beta-carotene) on the prevention of recurrence of colorectal cancer, found that the risk of recurrence of a new cancer was lower among those with high blood selenium levels. None of the dietary interventions in the pooled studies involved selenium supplementation – the analysis related blood levels of selenium to the recurrence of colorectal cancer (Jacobs et al). While each of the trials showed a lower risk of recurrence in subjects with the highest blood selenium level versus those with the lowest – and only one reached statistical significance – the pooled data did show a progressive decrease in the likelihood of colon cancer recurring with higher levels of selenium.

Summary
Since the causes of many types of cancer are largely unknown, it is usually not possible to recommend dietary changes aimed at prevention. However, nutrients such as selenium may offer a way to lower the risk of certain diseases or slow their progression. In different tumor models, different active forms of selenium may be more effective (Whanger) so information about the individual seleno-compound is important to assess potential health benefits. More research is needed to better understand the chemical species and metabolic activity of selenium in foods (Combs 2004). A mini review on the role of selenium in prostate cancer prevention suggested that the chemical form/s of selenium that can be metabolized to methylselenol are those that are thought to be most anticarcinogenically active (Combs 2004). Therefore, evaluating the results of studies on the effects of selenium on cancer and other health conditions requires information on the form of selenium used, the selenium status of the subjects, the biomarkers used such as nail clippings or blood levels and stage of the condition of the disease.

As a result of a contact made by President Minor at a selenium conference sponsored by the USDA ARS Human Nutrition Research Center in Grand Forks, ND, in November, research is underway to identify the specific form of selenium in mushrooms.

Cited and Additional References
·       Allen NE, Morris JS, Ngwenyama, RA, Key TJ. A case-control study of selenium in nails and prostate cancer risk in British men. British Journal of Cancer. 2004;90:1392-1396.

·       Beelman RB, Royse DJ,Chikthimmah N. Bioactive components in button mushroom Agaricus bisporus (J.Lge) imbach (agaricomycetideae) of nutritional, medicinal and biological importance. Review.
Int. J of Med Mushr. 2003;5:321-337.

·       Brooks JD, Metter EJ, Chan DW, Sokoll LF, Landia P, Nelson WG et al. Plasma selenium level before diagnosis and the risk of prostate cancer development. J Urol. 2001;166:2034-2038.

·       Broome CS, McArdle F, Kyle JAM, Andrews F, Lowe NM, Hart CA, Arthur JR, Jackson MJ. An increase in selenium intake improves immune function and poliovirus handling in adults with marginal selenium status.
Am J. Clin Nut.r 2004;80:154-62.

·       Clark LC, Combs Jr GF Turnbull BW, Slate EH, Chalker DK, Chow J, et al: Effects of selenium supplementation for cancer prevention in patients with carcinoma of the skin: a randomized clinical trial. JAMA. 1996;276:1957-1963.

·       Combs Jr GF. Status of selenium in prostate cancer prevention. British Journal of Cancer 2004; 91: 1950199.

·       DeVere White RW, Hackman RM, Soares, SE, Beckett, LA, Sun B. Effects of a mushroom mycelium extract on the treatment of prostate cancer.
Urology. 2002;60:640-644.

·       Duffield AJ, Thomson CD, Hill KE, Williams, S. An estimation of selenium requirements for New Zealanders. Am J Clin Nutr.1999;70:896-903.

·       Duffield-Lillico AJ, Shureiqu I, Lippman SM. Can selenium prevent colorectal cancer? A signpost from epidemiology. J. Natl Cancer Inst. 2004;92:1645-1647.

·       Ervin RB, Wang CY, Wright JD, Kennedy-Stephenson J. Dietary intake of selected minerals for the United States population 1999-2000. U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Health Statistics. April 27, 2004. No. 341.

·       Finley JW. Reduction of cancer risk by consumption of selenium-enriched plants: Enrichment of broccoli with selenium increases the anticarcinogenic properties of broccoli. J. Medicinal Food. 2003;6:19-26.

·       Food and Nutrition Board, Institute of Medicine, National Academy of Sciences, Panel on Dietary Antioxidants and Related Compounds, Subcommittees on Upper Reference Levels of Nutrients and Interpretation and Uses of Dietary Reference Intakes, and the Standing Committee on the Scientific Evaluation of Dietary Reference Intakes. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington DC: National Academy Press; 2000. www.nap.edu.

·       Herrmann RO. Fresh mushrooms 2000: report of a national telephone survey on mushroom usage and the marketing potential of selenium enrichment. Unpublished report to the Mushroom Council.

·       Jacobs ET, Jiang R, Alberts, DS, Greenberg ER, Gunter EW, Karagas MR, Lanza E, Ratnasinghe L, Reid ME, Schatzkin A, Smith-Warner SA, Wallace K, Martinez ME. Selenium and colorectal adenoma: Results of a pooled analysis.
J. Natl Cancer Inst. 2004, 96;1669-1675.

·       Li H, Stampfer MJ, Giovannucci EL, Morris JS, Willett WC, Gaziano JM, Ma J. A prospective study of plasma selenium levels and prostate cancer risk.
J. Natl Cancer Inst. 2004;96:696-703.

·       Lipsky K, Zigeuner R, Zischka M, Schips, L, Pummer K, Rehak, P, Hubner G. Selenium levels of patients with newly diagnosed prostate cancer compared with control group. Urology. 2004;63:912-916.

·       Meuillet E, Stratton S, Cherukuri DP, Goulet AC, Kagey J, Porterfield B, Nelson MA. Chemoprevention of prostate cancer with selenium: an update on current clinical trials and preclinical findings. J Cell Biochem. 2004;91:443-458.

·       Spolar MR, Schaffer EM, Beelman RB, Milner JA. Selenium-enriched Agaricus bisporus mushrooms suppress 7,12-dimethlybenz(a)anthracene bioactivation in mammary tissue. Cancer Letters 1999; 138:145-150.

·       Stanton JL. Mushroom purchase trigger concept test. Unpublished report to the Mushroom Council 2004. Department of Food Marketing, St. Joseph’s University, PA.

·       Taylor PR, Parnes HL, Lippman SM. Science peels the onion of selenium effects on prostate carcinogenisis. J Nat. Cancer Inst. 2004;96: 645-647.

·       van den Brandt PA, Zeegers, MPA, Bode P, Goldbohm, RA. Toenail selenium levels and the subsequent risk of prostate cancer. Cancer Epidemiol Biomark & Prev. 2003:12 866-871.

·       Whanger. Selenium and its relationship to cancer: an update. British Journal of Nutrition. 2004;91:11-28.

·       Yoshizawa K. Willett WC, Morris JS, Stampfer MJ, Spiegelman D, Rimm ED. Study of prediagnostic selenium level in toenails and the risk of advanced prostate cancer. J Natl Cancer Inst. 1998; 90:1219-24.

·      Zhao L, Zhao G, Zhao Z, Chen P, Tong J, Hu X. Selenium distribution in a Se-enriched mushrooms species of the genus Ganoderma. J. Agric. Food Chem 2004; 52:3954-3959.

[TOP]

B Vitamins
Mushrooms are a “good” or “excellent” source of several B vitamins involved in the release of energy from fat, protein and carbohydrate in food, or in other essential biochemical processes. According to the Mushroom Council’s Nutrition Labeling Toolkit for Mushrooms (2002), a Nutrition Facts serving (84 g) of white mushrooms is an “excellent source” (provides 20 percent of the Daily Value DV) of riboflavin, and a “good source” (10 percent of more of the DV) of pantothenic acid. A Nutrition Facts serving of brown mushrooms (84 g) or a Portabella mushroom (85 g) is a “good source” of riboflavin, niacin and pantothenic acid.

Cited References
·       Nutrition Labeling Toolkit for Mushrooms. Mushroom Council. www.mushroomcouncil.org.
[TOP]

Potassium
Potassium’s role as an essential mineral is well established. Potassium helps maintain normal heart rhythm, fluid balance, muscle, and nerve function. The Dietary Approaches to Stop Hypertension (DASH) Trial and the subsequent DASH-Sodium Trial looked at the effect of eating patterns rich in fruits, vegetables, fiber and low fat dairy products on the reduction of morbidity and mortality related to high blood pressure in the general population (Obarzanek).

The Food and Nutrition Board in 2004 set the Recommended Dietary Allowance for potassium at 4700 milligrams daily to lower blood pressure, offset the effects of salt intake and lower the risk of kidney stone formation. According to the National Health and Examination Survey, 1999-2000 for the U.S. population, the mean dietary intake of potassium for all ages and both genders is estimated to be 2628 mgs – only slightly more than half of the RDA (Ervin).

Mushrooms may be an under recognized source of potassium. White, crimini and Portabella mushrooms provide about 300 mg potassium per three ounce serving (Mushroom Council Nutrition Labeling Toolkit) and can help consumers increase their intake of this important nutrient. The Institute of Medicine’s report on the Dietary Reference Intakes for Water, Potassium, Sodium, Chloride and Sulfate identified mushrooms among high potassium foods with 550 mg per 1 cup cooked serving.
[TOP]

Cited and Additional References
·       Food and Nutrition Board, Institute of Medicine, National Academy of Sciences Dietary Reference Intakes; Water, potassium, sodium chloride, sulfate. 2004. http://www.nap.edu.

·       Ervin RB, Wang CY, Wright JD, Kennedy-Stephenson J. Dietary intake of selected minerals for the United States population 1999-2000. U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Health

·       Obarzanek E, Sacks Statistics. April 27, 2004. No. 341.
FM, Vollmer WM, Bray GA, Miller III, RE, Lin P-H, Karanja NM, Most-Windhauser MM, Moore TJ, Swain JS, Bales CW, Proschan MA. Effects on blood lipids of a blood pressure-lowering diet: The Dietary Approaches to Stop Hypertension (DASH) Trial. Am J Clin Nutr. 2001;74:80-9.

·       Vetter J. Data on sodium content of common edible mushrooms. Food Chemistry. 2003;81: 589-593.

Vitamin D
Vitamin D’s primary function is to regulate calcium metabolism and is recognized for its role in muscle and bone health and in the prevention of osteoporosis. However, there is increasing evidence for other potential health benefits of vitamin D with respect to cardiovascular health, cancer prevention, regulation of immune function and decreased risk of autoimmune diseases such as type 1 diabetes (Holick).

Vitamin D (calciferol) comprises a group of sterols and is termed the sunshine vitamin because it is produced in the skin of higher animals upon exposure to sunlight. Vitamin D comes in many forms, but the two important physiologically ones are vitamin D2 (ergocalciferol, originating from ergosterol, a plant and fungal sterol) and vitamin D3 (cholecalciferol, originating from a precursor of cholesterol in animals). Few foods are naturally rich sources of the vitamin – cod liver oil and oily fish such as salmon, mackerel and sardines. Milk, orange juice and some breads and cereals are fortified with vitamin D. White button mushrooms provide 64 IU of vitamin D per 84 gram serving (USDA National Nutrient Database for Standard Reference). The RDA for vitamin D is 5 micrograms (200 IU) a day for adults male and female to age 50. The RDA increases with age to 10 micrograms (400 IU) for adults 51-70 and 15 micrograms (600 IU) for adults 70 plus.

Because of the emerging role of vitamin D in health, vitamin D analysis was included in the research compositional research conducted at the University of Illinois described previously (Dikeman). This research could help clarify or verify existing information including:

·       The 1999 USDA value for vitamin D in mushrooms

·       References to wild mushrooms as a source of vitamin D2in the international literature (Mattila 2000 and 2002)

·       Mushrooms as contributing to the vitamin D intake of elderly Japanese (Nakamura)
[TOP]

However, research at the University of Illinois on cultivated mushrooms did not detect vitamin D as ergocalciferol in all samples although traces were identified in some samples. No ergocalciferol was detected in enoki or raw forms of 2nd stage crimini or Portabellas both stages.

The Council’s Nutrition Research Advisory Panel recommended that the questions about the presence of vitamin D2 in mushrooms be resolved. The USDA Nutrient Analysis of Mushrooms project described previously will again analyze for vitamin D2 in white button mushrooms to compare to the University of Illinois data.

Cited and Additional References
·       Dikeman CL, Bauer LL, Flickinger EA, Fahey GC Jr. Effects of stage of maturity and cooking on chemical composition of selected mushroom varieties with emphasis on carbohydrates, dietary fiber, chitin and vitamin D. 2004. Unpublished report to the Mushroom Council.

·       Holick MF. Vitamin D: importance in the prevention of cancers, type 1 diabetes, heart disease, and osteoporosis. Am J Clin Nutr. 2004;79:362-371.

·       Food and Nutrition Board, Institute of Medicine National Academy of Sciences Dietary Reference Intakes for calcium, phosphorus, magnesium vitamin D and fluoride. 2000. http://www.nap.edu.

·       Mattila P, Lampi AM, Ronkainen R,Toiva J, Piironen V. Sterol and vitamin D2 contents in some wild and cultivated mushrooms. Food Chemistry. 2002;76:293-298.

·       Mattila P, Suonpaa K, Piironen V. Functional properties of edible mushrooms. Nutrition. 2000. 16:694-696.

·       Nakamura K, Nashimoto BA, Okuda Y, Ota T, Yamamoto M. Fish as a major source of vitamin D in the Japanese diet. Nutrition. 2002;28:415-416.

·       Outila TA, Mattila PH, Piironen VI, Lamberg-Allardt, CJE. Bioavailability of vitamin D from wild edible mushrooms (Cantharellus tubaeformis) as measured with a human bioassay. Am J. Clin Nut. 1999;69:95-98.

·       U.S. Department of Agriculture, Agricultural Research Service. 2004. USDA National Nutrient Database for Standard Reference, Release 17. Nutrient Data Laboratory Home Page, http://www.nal.usda.gov/fnic/foodcomp.
[TOP]

Carbohydrates
The major dietary carbohydrates – mono- and disaccharides, sugar alcohols, oligosaccharides and polysaccharides – in selected mushroom varieties have been identified and quantified by the research at the University of Illinois. Polysaccharides have different structures and different properties, but the polysaccharides in mushrooms of interest are high molecular weight beta-glucans (Borchers 1999). However, the compositional analysis conducted by the University of Illinois determined that beta-glucan concentrations were low in all mushrooms regardless of raw or cooked or stage of maturity (Dikeman). Polysaccharides particularly in medicinal mushrooms are thought to be potent antitumor-active compounds. Most clinical evidence for antitumor activities comes from the commercial polysaccharides isolated from shiitake (Lentinus edodes) and maitake (Grifola frondosa) (Borchers 1999, Wasser). Lentinan, a beta-glucan polysaccharide from Lentinus edodes, has been approved for clinical use in Japan where studies (although not placebo-controlled and double blind) have been conducted (Borchers 1999)

The mechanisms by which polysaccharides in whole mushrooms and isolated mushroom compounds might modulate the immune system and potentially exert antitumor effects have been reviewed (Borchers 1999 and 2004). Some evidence indicates that the antitumor activities of mushroom polysaccharides may be attributed to the enhancement of the numbers and/or functions of macrophages, natural killer (NK) cells, and subsets of T cells, that is, the ability to affect both innate and adaptive immunity (Borchers 2004).

Cited and Additional References
·       Borchers AT, Stern JS, Hackman RM, Keen CL, Gershwin ME. Mini review: Mushrooms, tumors and immunity. Proc Soc Exp Biol Med. 1999;221:281-293.

·       Borchers AT, Keen CL, Gershwin ME. Mini review: Mushrooms, tumors and immunity: an update. Proc Soc Exp Biol Med. 2004; 229:393-406.

·       Cheung PCK, Lee MY. Fractionation and characterization of mushroom dietary fiber (Nonstarch polysaccharides) as potential neutraceuticals from sclerotia of Pleurotus tuber-regium (Fries) singer. J Agric Food Chem. 2000;48:3148-3151.

·       Dikeman CL, Bauer LL, Flickinger EA, Fahey GC Jr. Effects of stage of maturity and cooking on chemical composition of selected mushroom varieties with emphasis on carbohydrates, dietary fiber, chitin and vitamin D. 2004. Unpublished report to the Mushroom Council.

·      Wasser SP. Medicinal mushrooms as a source of antitumor and immunomodulating polysaccharides. Appl Microbiol Biotechnol 2002;60:258-274.

Weight Control
Carbohydrates
The popularity of low-carbohydrate diets like Atkins and South Beach has skyrocketed during the past few years and consumers are making a conscious effort to cut back on high-carbohydrate foods. Mushrooms are well positioned to benefit from the low-carb phenomenon. White, brown and Portabella mushrooms provide three grams of total carbohydrates per serving, including one gram of dietary fiber.

Despite the proliferation of “low-carb” products in the marketplace, most carbohydrate claims such as “low in carbs” or “carbohydrate free” are not currently permitted because they were not authorized by FDA when mandatory nutrition labeling was enacted in 1993. Specific to mushrooms, the statement “THREE GRAMS OF CARBOHYDRATES” can be used because it is a simple statement of fact. However, this statement cannot be modified to imply that the number of carbohydrates is low. For example, the claim “Only Three Grams of Carbs” would not be permitted because the word “only” suggests that the mushrooms are low in carbohydrate. Both the food industry and consumer groups have petitioned the FDA to establish nutrient content claims for carbohydrates and guidance regarding the use of the term “net carbs” on food packages.

The Council has funded a study on “The role of mushrooms included in a low carbohydrate diet on weight loss, blood lipids and satiety” Mark Kern, PhD, RD, San Diego State University, San Diego, CA. described previously.
[TOP]

Fat and calories
Other nutrient attributes of mushrooms, about 20 calories and less than a gram of fat per 84 g Nutrition Facts serving, also contributes to mushrooms role in weight loss and maintenance. Research completed in 2003 (Mushrooms: More than just another fungus) calculated the calorie and fat savings if males substituted a 4-ounce grilled Portabella mushroom for a 4-ounce grilled beef patty every time that they ate a grilled beef patty for one year. According to the calculation, they would experience an annual calorie savings of 18,400 calories, or a potential weight loss of 5.3 pounds and a yearly reduction of 2,725 grams of fat, assuming they did not compensate by eating other foods. The Council has funded research under the direction of Lawrence Cheskin, MD, Johns Hopkins University, to determine the effect of substituting white button mushrooms for higher calorie/fat foods on short and long term compensation. In addition, mushrooms’ high water content (over 90 percent), which can contribute to a feeling of fullness, and low calorie density help promote weight maintenance.

Cited and Additional References
·       Nutrition Labeling Toolkit for Mushrooms. Mushroom Council. www.mushroomcouncil.org.
·      Rolls BJ, Roe LS, Meengs JS. Salad and satiety: energy density and portion size of a first-course salad affect energy intake at lunch. J Am Diet Assoc. 2004; 104:1570-6.
[TOP]

Antioxidant Activity
Plant-based foods generally are considered important sources of antioxidants in the diet. Antioxidants help protect cells from potentially damaging physiological process known as “oxidative stress” (damage to healthy cells or DNA by unpaired electrons known as free radicals). Oxidative stress is thought to be associated with the development of chronic diseases including cancer, heart disease, conditions of aging including neurodegenerative diseases such as Parkinson’s and Alzheimer’s disease.

There are a variety of plant antioxidants with different chemical structures. There are the antioxidant nutrients such as vitamins C, E, beta-carotene and the mineral selenium (found in mushrooms) for which there are Recommended Dietary Allowances. However, there are thousands of other bioactive compounds in foods that have antioxidant activity but are not classified as “nutrients.” These “non-nutrient antioxidants” include phenolic compounds, secondary metabolites in plants that contribute to the plant’s color or taste, or in some way function for the plant’s benefit to attract pollinators or detract predators. There are no Recommended Dietary Allowances for these “non-nutrient” antioxidants.

The United States Department of Agriculture’s National Nutrient Database for Standard Reference contains information on several antioxidant nutrients (manganese, selenium, zinc, vitamins C and E, beta-carotene) and phytonutrients that function as antioxidants including lutein, lycopene, beta cryptoxanthin. Raw mushrooms are not a source of flavonoids according to the USDA Database for the Flavonoid Content of Selected Foods 2003. USDA in 2004 published a separate database for the proanthocyanidin content of selected foods (http://www.nal.usda.gov/fnic/foodcomp/Data/PA/PA.html.)

The various methods to measure a food’s antioxidant activity against specific oxidative radical species are beyond the purpose and scope of this Annual Report. Consensus as to the preferred method or methods is yet to be developed, although a 2004 international conference on antioxidant methods has sought some standardization. There are advantages and disadvantages to the different antioxidant capacity assays (tests) and there will be different antioxidant capacity values depending on the assay used. The same food item can be ranked differently depending on the assay used. This makes comparing total antioxidant capacities of foods difficult at present. However, an antioxidant capacity database is planned for posting on the USDA Nutrient Data Laboratory website (http://www.nal.usda.gov/fnic/foodcomp.). (Wu).
[TOP]

Table 1: Antioxidant Capacity of Selected Mushrooms by Different Assay Methods

Mushroom Type Antioxidant Assay^# and Value Reference

Unspecified as eaten in Italy FRAP
16.39 (mmol Fe²⁺/kg fresh weight Pellegrini

Unspecified as eaten in Italy TRAP
6.26 mmol Trolox/kg fresh weight Pellegrini

Unspecified as eaten in Italy TEAC
4.93 mmol Trolox/kg fresh weight Pellegrini

Button mushrooms DPPH
700 Trolox equivalents (TE)/100 grams Miller

White button ORAC
400 mmol Trolox equivalents (TE) /100 grams. Mushroom Council unpublished data from Brunswick Laboratories

Crimini ORAC 500 Trolox equivalents (TE) /100 grams Mushroom Council unpublished data from Brunswick Laboratories

Portabella ORAC 400 Trolox equivalents (TE) /100 grams Mushroom Council unpublished data from Brunswick Laboratories

Oyster ORAC 700 Trolox equivalents (TE) /100 grams Mushroom Council Unpublished data from Brunswick Laboratories

Shiitake ORAC 200 Trolox equivalents (TE) /100 grams Mushroom Council unpublished data from Brunswick Laboratories

Selected Indian Medicinal Mushrooms DPPH, FRAP, ORAC and ABTS Lakshmi

#Antioxidant Assays:

ORAC: The oxygen radical absorbance capacity (ORAC) assay used in early testing
has been made more robust (ORAC _fl) to allow for the measurement of the antioxidant
capacity of both water and fat soluble compounds in a given sample and thus
determine total antioxidant capacity (TAC).

TEAC: Trolox equivalent antioxidant capacity

TRAP: Total radical-trapping antioxidant parameter

FRAP: Ferric-reducing ability of plasma

DPPH: 2,2'-(4-tert-octylphenyl)-1-picrylhydraazyl)

Cited and Additional References
·       Mau JL, Lin HC, Song SF. Antioxidant properties of several specialty mushrooms.
Food Research International 2002;35:519-526.

·       Lakshmi B, Tilak JC, Adhikari S, Devasagayam TPA, Janardhanan KK. Evaluation of antioxidant activity of selected Indian mushrooms. Pharmaceutical Biology 2004; 42: 179-185.

·       Miller HE, Rigelhof, R, Marquart L, Prakash A, Kanter M. Antioxidant content of whole grain breakfast cereals, fruits and vegetables. J Am Col Nutr. 2000;19:312S-319S.

·       ORAC Certificate of Analysis, Brunswick Laboratories 2000. Unpublished report to the Mushroom Council.

·       Pellegrini N, Serafini, M, Colombi B, Del Rio, D, Salvatore S, Bianchi M, Brighenti F. Total antioxidant capacity of plant foods, beverages and oils consumed in Italy assessed by three different in vitro assays.
J. Nutr. 2003;133: 2812-2819.

·       U.S. Department of Agriculture, USDA Nutrient Database for Standard Reference, Release 17. and Flavonoids. Nutrient Data Laboratory Home Page http://www.nal.usda.gov/fnic/foodcomp.

·       Wu X, Beecher G, Holden JM, Haytowitz DB, Gebhardt S, Prior RL.   Lipophilic and hydrophilic antioxidant capacities of common foods in the United States. J Agric Food Chem. 2004;52:4026-4037.

Click here to learn about and order our new Health Products

[TOP]

Selenium | Consumer Awareness | Anti-Cancer Activity | Prostate Cancer | Colorectal Cancer |
B Vitamins | Potassium | Vitamin D | Carbohydrates | Weight Control | Antioxidant Activity

Back to Health & Nutrition