Safety Evaluation of Sclerotium from a Medicinal Mushroom, Lignosus cameronensis (Cultivar): Preclinical Toxicology Studies

Abstract

Twenty-eight days subacute toxicity studies performed in rats using sclerotial powder of Lignosus cameronensis cultivar was conducted to assess its safety for consumption prior to other scientific investigations on its medicinal benefits, nutraceutical or pharmaceutical application of the mushroom. The study was conducted at 250, 500, and 1000 mg/kg sclerotial powder of L. cameronensis cultivar (n = 5 for each respective dose, on both male and female groups) while control groups received only distilled water. At the end of the study (29th day), the animals were sacrificed followed by blood and organs collection for analysis. Subacute toxicity studies done shows that sclerotial powder of L. cameronensis cultivar at 250, 500, and 1000 mg/kg did not induce treatment related changes on behavioral patterns, gross physical appearance, growth pattern, body weight gain, values of hematological and clinical biochemical panels as well as histopathological findings on kidney, spleen, heart, lung and liver of the experimental rats. The no-observed-adverse-effect level dose for sclerotial powder of L. cameronensis cultivar in 28-days sub-acute toxicity study is determined to be 1000 mg/kg.

Nutritional evaluation on Lignosus cameronensis C. S. Tan, a medicinal Polyporaceae

“…Tetramic acids, indole diterpenoids, pyridines, diketopiperazines and 2,4,6‐tri acetylenic octane diacid are among the secondary metabolites produced in sclerotia of fungi that act as their chemical defence system against fungivorous predators . Yet, from this study and previous studies with animals , no accumulation of toxic elements and heavy metals were found in the cultivated sclerotia of Lignosus mushrooms. This makes cultivated L. cameronensis , L. rhinocerus and L. tigris safe materials, an important cornerstone of health food for human consumption.…”

“…Earlier oral administration of sclerotial powder from all three species; L. tigris E, L. rhinocerus and L. cameronensis to Sprague Dawley rats in 28‐day acute and sub‐acute toxicity assessments showed no mortality or signs of toxicity . As mushrooms collected in the wild could accumulate certain concerning levels of heavy metal pollutants , an assessment on the level of heavy metals in cultivated fungal materials was also carried out in this study to provide solid evidence that the overall safety of cultivated Lignosus materials (all three species) is not compromised by the presence of heavy metals, which are tolerated only at very low safety levels in food and herbal medicine .…”

“…Bhd. (Selangor, Malaysia) on sterilised substrate containing brown rice using proprietary formulation and left incubated in the dark at 24 °C for 3 months (duration for the formation of sclerotia) . The sclerotia were then harvested, without subjecting them to triggers that would lead to the next developmental stage of fruiting body.…”

“…Much of the carbohydrate in sclerotia of both species is starch . The closely related L. cameronensis with its origin from tropical forest in Lata Iskandar (4°17.46′N 101°34.41′E), Pahang, located over 1,000 m (3,300 ft) above sea level on the Titiwangsa Range could contain similar nutrient composition. L. cameronensis like its other close relatives in the wild could have adapted to absorb, produce and store different amount of nutrients from poor soils for growth and reproduction.…”