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Traditional use of the tiger milk medicinal mushroom, Lignosus rhinocerus, to treat various illnesses has been recorded for > 4 centuries. Successful cultivation of L. rhinocerus using proprietary solid-state fermentation (SSF) technology by LiGNO Biotech has enabled large-scale production of L. rhinocerus sclerotia (termed L. rhinocerus TM02) and further investigations into its medicinal properties. Pharmacological activities of L. rhinocerus TM02, including its antioxidant, anti-inflammatory, anticancer, and immunomodulatory effects and the bioactive components responsible, have been validated by various scientific studies. In this study, we assessed the consistency of the bioactive components in 11 batches of L. rhinocerus TM02 produced over a 9-year period. The different batches of L. rhinocerus TM02 consisted of stable protein, polysaccharide, and glycoprotein contents, and all tested samples were comparable to the wild type. L. rhinocerus TM02 had greater protein, carbohydrate, and glycoprotein contents, which were mostly bioactive compared to another cultivar from a different cultivation technology (TM-UN). Together with previous scientific validations, L. rhinocerus TM02 produced using SSF cultivation is of optimal quality with high consistent bioactive contents, which can be an appropriate indicator for quality validation of the much sought-after medicinal mushroom, L. rhinocerus.

The Tiger Milk Mushroom (Lignosus spp.) is an important medicinal mushroom in Southeast Asia and has been consumed frequently by the natives as a cure for a variety of illnesses. In this study, we hypothesized that Lignosus tigris (cultivar E) sclerotium may contain high nutritional value and antioxidant properties, is nontoxic and a potential candidate as a dietary supplement. The chemical and amino acid compositions of the sclerotium were evaluated and antioxidant activities of the sclerotial extracts were assessed using ferric reducing antioxidant power; 1,1-diphenyl-2-picrylhydrazyl; and superoxide anion radical scavenging assays. Acute toxicity of the L. tigris E sclerotium was assessed using a rat model study. The sclerotium was found to be rich in carbohydrate, protein, and dietary fibers with small amounts of fat, calories, and sugar. The amino acid composition of the protein contains all essential amino acids, with a protein score of 47. The sclerotial extracts contain phenolics, terpenoids, and glucan. The ferric reducing antioxidant power values of the various sclerotial extracts (hot water, cold water, and methanol) ranged from 0.008 to 0.015 mmol min(-1) g(-1) extract, while the 1,1-diphenyl-2-picrylhydrazyl and superoxide anion radical scavenging activities ranged from 0.11 to 0.13, and -2.81 to 9.613 mmol Trolox equivalents g(-1) extract, respectively. Acute toxicity assessment indicated that L. tigris E sclerotial powder was not toxic at the dose of 2000 mg kg(-1). In conclusion, L. tigris E sclerotium has the potential to be developed into a functional food and nutraceutical.

Background Genome mining facilitated by heterologous systems is an emerging approach to access the chemical diversity encoded in basidiomycete genomes. In this study, three sesquiterpene synthase genes, GME3634, GME3638, and GME9210, which were highly expressed in the sclerotium of the medicinal mushroom Lignosus rhinocerotis, were cloned and heterologously expressed in a yeast system. Results Metabolite profile analysis of the yeast culture extracts by GC–MS showed the production of several sesquiterpene alcohols (C15H26O), including cadinols and germacrene D-4-ol as major products. Other detected sesquiterpenes include selina-6-en-4-ol, β-elemene, β-cubebene, and cedrene. Two purified major compounds namely (+)-torreyol and α-cadinol synthesised by GME3638 and GME3634 respectively, are stereoisomers and their chemical structures were confirmed by 1H and 13C NMR. Phylogenetic analysis revealed that GME3638 and GME3634 are a pair of orthologues, and are grouped together with terpene synthases that synthesise cadinenes and related sesquiterpenes. (+)-Torreyol and α-cadinol were tested against a panel of human cancer cell lines and the latter was found to exhibit selective potent cytotoxicity in breast adenocarcinoma cells (MCF7) with IC50 value of 3.5 ± 0.58 μg/ml while α-cadinol is less active (IC50 = 18.0 ± 3.27 μg/ml). Conclusions This demonstrates that yeast-based genome mining, guided by transcriptomics, is a promising approach for uncovering bioactive compounds from medicinal mushrooms. Electronic supplementary material The online version of this article (doi:10.1186/s12934-017-0713-x) contains supplementary material, which is available to authorized users.