Hericium coralloides

Hericium coralloides, commonly known as the coral tooth or bear's head fungus, is a striking white-rot fungus that grows as a branched, coral-like or delicately antler-shaped cluster up to about 30 cm across. Short spines hang downward in rows along the upper sides of its branches. It fruits on dead and dying broadleaf trees — oak, beech, maple, walnut, sycamore and other hardwoods — most often on logs and stumps in temperate forests across North America, Europe, China and Japan. As a saprotroph it helps decompose dead wood and recycle forest nutrients. It is both edible and choice, with a crab- or lobster-like texture when cooked, and is studied for its neurotrophic compounds.

History

Hericium coralloides belongs to the tooth-fungus family Hericiaceae in the order Russulales. The genus name Hericium derives from the Latin for hedgehog, a reference to the spiny, downward-hanging teeth shared across the genus, while the epithet coralloides means "coral-like." It is closely related to the better-known lion's mane (H. erinaceus) and to H. abietis, and is reliably distinguished from H. erinaceus by its branching habit: in H. coralloides the spines fork and arise from a many-branched body, whereas in H. erinaceus the spines cascade individually from a single unbranched mass. The species is uncommon enough in parts of Europe that it appears on national Red Lists, where its wild fruit bodies are protected.

Overview

Hericium coralloides is valued both as a gourmet edible and as a subject of medicinal-mushroom research. Chemically it is best characterized by the corallocins — corallocins A–C, isolated by Wittstein and colleagues in 2016, are nerve-growth-factor (NGF) and brain-derived neurotrophic factor (BDNF) inducing metabolites isolated specifically from this species, and the related corallocins D–E were later described from its fruiting bodies. Like other members of the genus it also contains bioactive polysaccharides studied for antitumor and immunomodulating activity. Much of the popular health literature on "lion's mane" neurotrophic compounds (hericenones and erinacines) refers chiefly to H. erinaceus; H. coralloides shares the same neurotrophic compound class through its own corallocins rather than being identical to it. As a saprotrophic species it is comparatively easy to cultivate on sterilized hardwood sawdust or by the traditional log method, making it accessible to growers as well as foragers.