Tramesan, a novel polysaccharide from Trametes versicolor. Structural characterization and biological effects

Abstract

Mushrooms represent a formidable source of bioactive compounds. Some of these may be considered as biological response modifiers; these include compounds with a specific biological function: antibiotics (e.g. plectasin), immune system stimulator (e,g, lentinan), antitumor agents (e.g. krestin, PSK) and hypolipidemic agents (e.g. lovastatin) inter alia. In this study, we focused on the Chinese medicinal mushroom “yun zhi”, Trametes versicolor, traditionally used for (cit.) “replenish essence and qi (vital energy)”. Previous studies indicated the potential activity of extracts from culture filtrate of asexual mycelia of T. versicolor in controlling the growth and secondary metabolism (e.g. mycotoxins) of plant pathogenic fungi. The quest of active principles produced by T. versicolor, allowed us characterising an exo-polysaccharide released in its culture filtrate and naming it Tramesan. Herein we evaluate the biological activity of Tramesan in different organisms: plants, mammals and plant pathogenic fungi. We suggest that the bioactivity of Tramesan relies mostly on its ability to act as pro antioxidant molecule regardless the biological system on which it was applied.

Tramesan Elicits Durum Wheat Defense against the Septoria Disease Complex

“…We hypothesize that Tramesan is recognized by specific receptors that, in turn, activate pathways leading to an antioxidant response in the host. Tramesan acts in several organisms (mammals, fungi, and plants) as an activator of antioxidant defenses [20]; when employed against mycotoxigenic fungi, it switches off aflatoxin synthesis-a process closely related to the antioxidant system of the cell-in Aspergillus section Flavi [42]. Therefore, along with inducing plant defenses, Tramesan can lower circulating reactive oxygen species (ROS) at the plant-pathogen interface, thus creating a less favorable environment for the necrotrophic growth of plant pathogens such as P. nodorum.…”

“…The entire mass (liquid medium + mycelium) was then homogenized using a Waring blender (speed 5 for 3 pulses of 2 min each) and added at 5% v/v to PDB medium and grown over 14 days. Tramesan was purified as described by [20], then 2.3 g of lyophilized Tramesan were dissolved in 1 L of distilled sterile water. This solution was used to spray wheat plants in a greenhouse environment.…”

“…This solution was used to spray wheat plants in a greenhouse environment. Plants were treated with Tramesan at 3.3 µM as previously described [20]. Tramesan was formulated with 0.1% v/v of Tween 20 as surfactant to increase its adhesion to leaves.…”

“…In this study, we explore the ability of purified Tramesan, a 23 kDa α-heteropolysaccaride secreted by the basidiomycete Trametes versicolor [20], to act as an elicitor of durum wheat defenses for SLBC. Tramesan has demonstrated biological activity on fungal, plant, and animal cells [19,20]. Tramesan appears to act as a pro-antioxidant by inducing the expression of oxidative stress response-related genes, thus triggering a biological response.…”

Antibacterial Activity of Essential Oils and Trametes versicolor Extract against Clavibacter michiganensis subsp. michiganensis and Ralstonia solanacearum for Seed Treatment and Development of a Rapid In Vivo Assay

“…For this reason, many scientific works have focused on developing alternative environmentally friendly measures to the use of pesticides for managing crop diseases [19][20][21][22]. A very promising approach consists in the use of natural compounds such as plant or fungal extracts and their active principles (alkaloids, phenols, monoterpenes and sesquiterpenes, isoprenoids), which have been studied for their various antimicrobic and antioxidant properties [23][24][25][26][27]. EOs (essential oils) are secondary metabolites accumulated by aromatic or medical plants and extracted from leaves, flowers, roots, and barks.…”