Chicken of the Woods- Medicinal Mycology
Laetiporus sulphureus [Bull.] Murill
Laetiporus comes from the Latin meaning “a wealth of pores;” sulphureus means “a bright yellow color.” The beautiful yellow-orange colored fruiting body can approach red in some specimens. This mushroom is known as chicken of the woods because of its overall flavor and texture.
This yellow-pored mushroom is widely found in eastern United States and Canada on hardwoods. The pigment color is due largely to laetiporic acid. There are other species in the genus. Fruiting bodies on conifers in the West are known as L. conifericola and L. gilbertsonii occurs on hardwoods (frequently eucalyptus); L. huronensis and L. perscinus are lesser encountered species in the Great Lakes and Southeast regions, respectively.
There is considerable taxonomic confusion with DNA and other work suggesting at least eight clades. Work by Lindner and Banik (2008) looked at North American species and suggested five major clades, including L. sulphureus sensu stricto (ss) isolates with yellow pores. Worldwide work by Vasaitis et al. (2009) concluded it is not possible to define L. sulphureus ss. Enough taxonomy. Let us move on.
Older specimens can smell like rotten eggs, but the younger specimens or the newer growths are very pleasant. Most species of the group are generally considered edible but there are reports in the literature about possible untoward effects. One case involved a six-year old girl who experienced hallucinations after nibbling on a sulfur shelf (Appleton et al., 1988). The Mycological Society of San Francisco toxicology committee reported one ingestion in which an adult experienced a tingling sensation in fingers, a floating sensation, dizziness and disorientation. It was not noted if it was growing on a hardwood or conifer. There is uncertainty whether the occasional bad reactions from consuming chicken of the woods are caused by old specimens, improperly cooked specimens, compounds coming from the host tree (Eucalyptus has been mentioned as a suspect host), or some other cause. Besides the variable and often garish colors, Laetiporus species are notable for the enormous size they can attain. One specimen discovered in England in 2003 measured more than sixteen feet in circumference and estimated to weigh, at that time, nearly 700 pounds.
Hordenine, tyramine, N-methyl tyramine, and two unidentified alkaloids have been reported from western specimens. A lectin, similar to the mosquito toxin MTX2 (from Bacillus sphaericus), and the insecticidal cyclodepsipeptide have been isolated from the polypore. I have smoldered a small piece of the dried mushroom as a mosquito repellant in my tent with good success. Egonol and derivates are used as melanin inhibitors and whitening agents to treat sunburned skin after UV irradiation, and skin pigmentation such as pregnancy mask.
The mushroom can be preserved for medicine by drying in thin slices and later decocting a tea, or by preparing a fresh decoction and preserving in minimum 25% alcohol. Large-scale commercial cultivation is now possible, suggesting the possibility of year round availability (Pleszczynska et al., 2013).
Ergosterol peroxide; cerevisterol; sulphureuines B-H; lanostanoid triterpenes including 3-oxosulfurenic acid; laetirobin; melanin; mannitol; trehalose; alpha-, gamma-, and delta- tocopherols; oxalic, citric, cinnamic and p-hydroxybenzoic acids; three mycophenolic acid derivatives; seven sulphureuines (B-H); beauvericin (cyclic peptide); laminarin; ergothioneine; GABA (gamma-aminobutyric acid); triterpenoids such as eburicoic acid, sulfurenic acid, acetyl eburicoic acid, acetyl tremaetenolic acid, and 15 alpha-hydroxytrametenolic acid; isoprenoid ubiquinone Q9; laetiporic acids (A-C); LSL (lectin); masutakeside 1; masutakin acid A; egonol; demethoxyegonol; egonol glucoside; egonol gentiobioside; sulphureuines B-H, agripilol A, 3beta-hydroxy-11,12-O-isopropyldrimene, and sulphurenic acid.
Chicken of the woods exhibits a number of health benefits. The antioxidant activity is similar to alpha tocopherol and the synthetic preservative BHA according to Turkoglu et al. (2007). The same study (Turkoglu et al., 2007) found it strongly inhibited gram-positive bacteria and Candida species. Earlier work identified activity against methicillin-resistant Staphylococcus aureus (MRSA) (Ershova et al., 2003). In submerged cultivation, Leuconostoc mesenteroides growth was suppressed. This bacterium is responsible for fermenting sauerkraut and pickles. It is probably not a good idea to try and pickle the mushroom and cabbage in same crockpot.
On the other hand, alcohol extracts help preserve foods against Aspergillus flavus (Petrovic et al., 2014), the source of the highly carcinogenic aflatoxin. A screening of 57 wood-damaging fungi found chicken of the woods the most active inhibitor of HIV-1 reverse transcriptase (Mlinaric et al., 2005). Eburicoic acid is a potent inducer of apoptosis in HL-60 human myeloid leukemia cell lines (León et al., 2004). Work by Kang et al. (1982) found hot water extracts suppressed the growth of Sarcoma 180 in mice, suggesting anti-carcinogenic activity. Egonol, demethoxyegonol and egonol glucoside all exhibited cytotoxicity against human stomach cancer KATO III cells (Yoshikawa et al., 2001). Egonol gentiobioside promotes the biosynthesis of estrogen by aromatase. Estrogen deficiency is associated with a variety of health concerns including osteoporosis, atherosclerosis and Alzheimer’s disease (Lu et al., 2012).
Exposure to radiation can deplete testosterone-binding globulin, which can affect androgen ligand binding. Lipid polyene preparations from this mushroom have been found to help restore radiation-induced changes (Popoff and Kapich, 2010). This may have application to restoration of hormone health after chemotherapy.
The compound (+/-)-laertirobin was isolated from Laetiporus sulphureus growing on black locust tree. Early studies found it enters tumor cells, blocks cell division at a late stage of mitosis, and invokes apoptosis, or programmed cell death (Lear et al., 2009). It has been synthesized and is presently being investigated by Xenobe Research Institute in California for possible treatment on various human cancers.
Mycophenolic acids and sulphureuines have been isolated from the polypore. Moderate cytoxicity has been noted against HL-60 (leukemia), SMMC-7721 (hepatoma), A-549 (lung) and MCF-7 (breast) cancer cell lines (Fan et al., 2014; He et al., 2015). Eburicoic acid showed moderate activity against five cancer cell lines; HL-60, SMMC-7721, A-549 and MCF-7, mentioned above, as well as SW-480 (colorectal) cell lines were inhibited by this compound (He et al., 2015).
Lanostanoid triterpenes induced apoptosis on HL-60 (leukemia) cell lines over ten years ago (León et al., 2004). Work by Ríos et al. (2012) identified lanostanoid triterpenes with potential anti-cancer activity.
Cell wall preparations from the fruiting body effectively induce mutanase that helps remove Streptococcus mutans biofilm from teeth and dentures. A water soluble glucan produced by the bacterium, stimulates cariogenic pathogens causing dental disease. Mutanase and dextranase, found in chicken of the woods, hydrolyze and remove dental and denture plaque (Wiater et al., 2008). These two compounds are found in Biotene, a commercial dental product used by individuals suffering dry mouth.
Polysaccharides produced by Laetiporus have been shown to inhibit the expression of pro-inflammatory mediators by suppressing NF-kB activity (Jayasooriya et al., 2011). This suggests anti-inflammatory activity.
Melanin has been isolated from mycelium of chicken of the woods, yielding about 2.49% of fresh weight. Melanin is not only a free radical scavenger, but may play a role in pineal gland health and production of melatonin.
Chicken of the woods contains laminarin, a water insoluble polysaccharide more commonly found in seaweed and algae. The linear (1>3)-linked beta glucan laminaran inhibited formation of human melanoma SK-MEL-28 and colon cancer DLD-1 cell lines (Menshova et al., 2014). Earlier work by Park et al. (2013) found laminarin induced apoptosis in HT-29 colon cancer cells and inhibited the heregulin-stimulated phosphorylation of ErbB2. ErbB2 is also known as HER2 and is a human epidermal growth factor receptor. An over-expression of this oncogene has been shown to play an important role in development of 15-30 % of aggressive breast cancers. It is also implicated in ovarian, stomach and uterine cancers. HER2 is the target of Herceptin, which increases p27, a protein that halts cell proliferation. One-third of patients respond well to Herceptin cancer treatment.
Type 2 diabetes is a growing health epidemic. Syndrome X, also known as diabesity is a complex mixture of insulin resistance, high blood sugar, high cholesterol, cardiovascular risk, and obesity. The compound dehydrotrametenolic acid acts as an insulin sensitizer in glucose tolerance tests (Sato et al., 2002). It induces adipose conversion, activates peroxisome proliferator-activated receptor gamma (PPAR gamma), and reduces hyperglycemia in animal models of non-insulin dependent diabetes. This compound is also found in Poria cocos, a polypore widely used in traditional Chinese medicine. Submerged mycelial cultures produce an extracellular polysaccharide (EPS) with insulinotropic properties. Researchers found the proliferation of animal insulinoma cells increased by 152%, suggesting both cell proliferation and insulin secretion (Hwang et al., 2008). The same study found EPS protected the cells against strepatzocin-induced apoptosis.
The key enzyme in the metabolism of fat is lipase. In one study an extract of chicken of the woods inhibited pancreatic lipase by 83%, comparable to the commercially available lipase inhibitor Orlistat (Slanc et al., 2004).
Lovastatin is naturally found in oyster mushroom (Pleurotus species), and helps block cholesterol synthesis with the side effects of statin drugs. Work by Lee et al. (2006) found mycelial extracts of oyster mushroom and chicken of the woods showed the highest inhibition rates of HMG-CoA reductase, the limiting enzyme in biosynthesis of cholesterol, by 37.2% and 29.1%, respectively. Chicken of the woods showed high inhibition activity even though it had a lower level of lovastatin. The authors suggest there may be a compound in mushroom, with synergistic activity. Statin drugs (Crestor and Lipitor) decrease blood plasma levels of coenzyme Q10, and can lead to rhabdomyolysis, a rare but serious side-effect. Coenzyme Q10 has been reported to reverse this condition and associated acute renal failure (Wang et al., 2015). It is interesting to note that many of the North American studies on the connection between muscle related symptoms, statin use and Q10 show no correlation. One study of 50 patients treated with statins, and reporting muscle pain, was conducted by Skarlovnik et al. (2014). One group of 25 patients received 100 mg of Q10 daily and the other group of 25 got a placebo, for 30 days. The supplementation effectively reduced the mild to moderate statin-induced muscular symptoms. Pain Severity scores and Pain Interference scores in placebo group did not change.
Chicken of the woods contains CoQ9. Research in mice found a reduction of CoQ9 led to brain specific impairment, leading to mitochondrial encelphalomyopathy (Garcia-Corzo et al., 2013).
The mushroom also exhibits anti-thrombin activity. An unusual study fused chicken of the woods with the edible mushroom Hypsizygus marmoreus (=H. tesselatus; common name beech mushroom and buna shemiji) resulting in a thrombin time of only 170.5 seconds (Okamura et al., 2000).
Some things to think about the next time you sit down to a meal of chicken of the woods. Bon apetit!