Ganoderma tsugae, commonly referred to as Hemlock varnish shelf in North America, is a flat polypore mushroom from the genus Ganoderma found on decaying hemlock wood and used in traditional Chinese medicine for health-promoting properties. A close relative to true reishi (Ganoderma lucidum), but only growing on eastern hemlock trees instead of hardwood trees where true reishi typically grows throughout China and parts of Europe; recent research studies have demonstrated its antitumor, anti-inflammatory, immunomodulatory, hepatoprotective and antilipogenic effects compared to their counterparts.

Studies demonstrate the mushrooms’ neuroprotective effects, such as protecting neuronal morphology from being damaged by an oxidative stressor, reducing Alzheimer’s and Parkinson’s diseases, improving cognitive function in rats, and improving locomotion and spatial memory in mice. Their effectiveness may be attributed to increasing antioxidant enzyme production such as superoxide dismutase and catalase while decreasing expressions of pro-inflammatory cytokines such as malonaldehyde.

Researchers have also demonstrated that GTDE, derived from G. tsugae, protects against memory loss and attenuates cognitive decline in D-galactose-induced aging of Long Evans rats by alleviating oxidative stress. GTDE significantly enhances SOD and heme oxygenase-1 activity while decreasing concentrations of Age-Associated Genes in their brains and improving spontaneous behavior and spatial memory in rats exposed to D-galactose.

GTDE also increases production of BDNF by neurons and promotes dendritic branching in these cells, suggesting that its combination with other compounds found in fungus could help prevent aging and enhance memory.

To prepare tea from Ganoderma Tsugae mushrooms, first remove its cap and stems before grinding or chopping with a kitchen tool or knife. Boil for 30 minutes at medium temperature before straining out any liquid that accumulates – this should produce a pleasant tasting tea that should improve general health among most adults. A few teaspoons should suffice daily; beware however of overdoing any medicinal fungus use as too much can cause digestive discomfort; store correctly afterwards! This article was contributed by one of our Mushrooms of Field and Forest course students!