Oyster Mushroom – Pleurotus ostreatus

Japanese nameHiratake
Chinese namePing Gu

One of the principal culinary mushrooms, P. ostreatus fruiting bodies contain lovastatin in concentrations ranging from 0.7-2.8% dried weight depending on the strain.
P. ostreatus has also been commercialized as a source of polysaccharide extracts for immune support and shows promise for general health maintenance1,2.
Related species including Pleurotus eryngii, Pleurotus tuber-regium and Pleurotus citronopileatus show similar immune-modulating and cholesterol-lowering activity3-7.

CHOLESTEROL CONTROL – Dried P. ostreatus fed to hamsters at 2% of a high fat diet for six months is reported to have lowered VLDL by 65-80% and total serum lipid levels by 40% and to totally negate increases in triglyceride and liver cholesterol levels associated with chronic alcohol intake8-10. Multiple animal studies show P. ostreatus to produce improvements in blood lipid levels at 5% of diet11-17. Intake of more than 5% was seen to suppress appetite18.
Bobek et al reported reductions in cholesterol in humans from intake of 15-20g/day11 and Khatun et al reported P. ostreatus to reduce cholesterol levels in diabetic patients19. However, in a small clinical study on HIV patients with elevated non-HDL cholesterol (>160mg/dl) who were taking protease inhibitors no significant change was seen from supplementation with 15g/day freeze-dried P. ostreatus for 8 weeks (abnormalities in lipid metabolism are a common side effect of anti-retroviral treatment)20,21.

ANTI-AGEING -As well as having immunomodulatory, anti-cancer and hepatoprotective properties in common with those from other mushrooms, polysaccharides from P. ostreatus have been shown to increase activity of catalase, superoxide dismutase and glutathione peroxidase, as well as counter age-related reductions in levels of vitamins C and E22-27.

CLINICAL SUMMARY
Therapeutic Application – General health maintenance, especially in the elderly. Can be prescribed for cholesterol control, although Monascus purpureus products (Hong Qu Mi – Red Yeast Rice) usually give a more controlled dose of lovastatin.
Key Components – Lovastatin, polysaccharides.
Dose – 1-2g/day polysaccharide extract or 2-3g/day mycelial biomass for general health maintenance. 10-15g/day dried fruit body for cholesterol control.
Caution – Patients taking protease inhibitors such as ritonavir, indinavir etc., which have been shown to raise statin levels significantly through common use of the CYP3A4 enzyme system.

REFERENCES
1. IImmunomodulatory effect of pleuran (β-glucan from Pleurotus ostreatus) in children with recurrent respiratory tract infections. Jesenak M, Majtan J, Rennerova Z, Kyselovic J, Banovcin P, Hrubisko M. Int Immunopharmacol. 2013;15(2):395–399.
2. Anti-allergic effect of Pleuran (β-glucan from Pleurotus ostreatus) in children with recurrent respiratory tract infections. Jesenak M, Hrubisko M, Majtan J, Rennerova Z, Banovcin P. Phytother Res. 2014;28(3):471–474.
3. Evaluation of mushroom dietary fiber (nonstarch polysaccharides) from sclerotia of Pleurotus tuber-regium (Fries) singer as a potential antitumor agent. Zhang M, Cheung PC, Zhang LJ. Agric Food Chem. 2001;49(10):5059–5062.
4. Optimization for the production of water-soluble polysaccharide from Pleurotus citrinopileatus in submerged culture and its antitumor effect. Wang JC, Hu SH, Liang ZC, Yeh CJ. Appl Microbiol Biotechnol. 2005;67(6):759–766.
5. Hypolipidemic effect of Pleurotus eryngii extract in fat-loaded mice. Mizutani T, Inatomi S, Inazu A, Kawahara E. J Nutr Sci Vitaminol. 2010;56(1):48–53.
6. Dietary effect of Pleurotus eryngii on biochemical function and histology in hypercholesterolemic rats. Alam N, Yoon KN, Lee JS, Cho HJ, Shim MJ, Lee TS. Saudi J Biol Sci. 2011;18(4):403–409.
7. Antitumor activity of a polysaccharide from Pleurotus eryngii on mice bearing renal cancer. Yang Z, Xu J, Fu Q, Fu X, Shu T, Bi Y, Song B. Carbohydr Polym. 2013;95(2):615–620.
8. Effect of mushroom Pleurotus ostreatus and isolated fungal polysaccharide on serum and liver lipids in Syrian hamsters with hyperlipoproteinemia. Bobek P, Ginter E, Kuniak L, Babala J, Jurcovicova M, Ozdín L, Cerven J. Nutrition. 1991;7(2):105–108.
9. Cholesterol-lowering effect of the mushroom Pleurotus ostreatus in hereditary hypercholesterolemic rats. Bobek P, Ginter E, Jurcovicová M, Kuniak L. Ann Nutr Metab. 1991;35(4):191–195.
10. Effect of oyster fungus (Pleurotus ostreatus) on serum and liver lipids of Syrian hamsters with a chronic alcohol intake. Bobek P, Ginter E, Jurcovicová M, Ozdín L, Mekinová D. Physiol Res. 1991;40(3):327–332.
11. Dose-dependent hypocholesterolaemic effect of oyster mushroom (Pleurotus ostreatus) in rats. Bobek P, Ozdín L, Kajaba I. Physiol Res. 1997;46(4):327–329.
12. Dose- and time-dependent hypocholesterolemic effect of oyster mushroom (Pleurotus ostreatus) in rats. Bobek P, Ozdín L, Galbavý S. Nutrition. 1998;14(3):282–286.
13. Hypocholesterolemic activity of the genus Pleurotus (Jacq.: Fr.) P. Kumm. (Agaricales s. I., Basidiomycetes). Gunde-Cimerman N, Plemenitas A. Int J Med Mushrooms. 2001;3(4).
14. Evidence for the anti-hyperlipidaemic activity of the edible fungus Pleurotus ostreatus. Opletal L, Jahodár L, Chobot V, Zdanský P, Lukes J, Brátová M, Solichová D, Blunden G, Dacke CG, Patel AV. Br J Biomed Sci. 1997;54(4):240–243.
15. Dietary mushroom (Pleurotus ostreatus) ameliorates atherogenic lipid in hypercholesterolaemic rats. Hossain S, Hashimoto M, Choudhury EK, Alam N, Hussain S, Hasan M, Choudhury SK, Mahmud I. Clin Exp Pharmacol Physiol. 2003;30(7):470–475.
16. Role of oyster mushroom (Pleurotus florida) as hypocholesterolemic/ antiatherogenic agent. Bajaj M, Vadhera S, Brar AP, Soni GL. Indian J Exp Biol. 1997;35(10):1070–1075.
17. Cholesterol-lowering effect of Pleurotus species (Agaricomycetideae) (Abstracts of papers published in 1991-1999). Int J Med Mushrooms. 1999;1(4):371–380.
18. A lectin from the edible and medicinal mushroom Pleurotus ostreatus (Jacq.: Fr.) Kumm. as a food intake suppressing substance. Kawagishi H, Yokoyama S, Nakamura H, Tokuyama S. Int J Med Mushrooms. 2001;3(2-3):168.
19. Oyster mushroom reduced blood glucose and cholesterol in diabetic subjects. Khatun K, Mahtab H, Khanam PA, Sayeed MA, Khan KA. Mymensingh Med J. 2007;16(1):94–99.
20. Antihyperlipidemic effect of Pleurotus ostreatus in HIV: results of a pilot proof-of-principle clinical trial. Abrams DI, Couey P, Shade SB, Kelly ME, Kamanu-Elias N, Stamets PE. Int J Med Mushrooms. 2007;9(3):204.
21. Antihyperlipidemic effects of Pleurotus ostreatus (oyster mushrooms) in HIV-infected individuals taking antiretroviral therapy. Abrams DI, Couey P, Shade SB, Kelly ME, Kamanu-Elias N, Stamets P. BMC Complement Altern Med. 2011;11:60.
22. Effect of oyster mushroom (Pleurotus ostreatus) on pathological changes in dimethylhydrazine-induced rat colon cancer. Bobek P, Galbavy S, Ozdin L. Oncol Rep. 1998;5(3):727–730.
23. Cytotoxic effect of oyster mushroom Pleurotus ostreatus on human androgen-independent prostate cancer PC-3 cell. Gu YH, Sivam G. J Med Food. 2006;9(2):196–204.
24. Effects of Lentinus edodes, Grifola frondosa and Pleurotus ostreatus administration on cancer outbreak and activities of macrophages and lymphocytes in mice treated with a carcinogen N-butyl-N-butanolnitrosamine. Kurashige S, Aleusawa Y, Endo F. Immunopharm Immunodetox. 1997;19(2):175–183.
25. Antioxidant activity of the oyster mushroom, Pleurotus ostreatus, on CCl(4)-induced liver injury in rats. Jayakumar T, Ramesh E, Geraldine P. Food Chem Toxicol. 2006;44(12):1989–1996.
26. Protective effect of an extract of the oyster mushroom, Pleurotus ostreatus, on antioxidants of major organs of aged rats. Jayakumar T, Thomas PA, Geraldine P. Exp Gerontol. 2007;42(3):183–191.
27. An extract of the oyster mushroom, Pleurotus ostreatus, increases catalase gene expression and reduces protein oxidation during aging in rats. Jayakumar T, Thomas PA, Isai M, Geraldine P. Zhong Xi Yi Jie He Xue Bao. 2010;8(8):774–780.