Bioactive Properties of Commercial Reishi Mushroom Products in Powder Form

Abstract

Ganoderma lucidum (Reishi mushroom) has well known history of use with regards to ensuring health effects and longevity in Asian countries. Besides, it has an antioxidative protection system to protect the living organism from the action of free radicals. This study examines the bioactive properties of powder form of G. lucidum as a natural functional agent and the antimicrobial effects of the 5 different commercially sold powder of the G. lucidum mushrooms were investigated against various pathogenic bacteria and molds. For this purpose, the phenolic content, antioxidant capacity of G. lucidum samples were determined. The antimicrobial effects of the 5 different G. lucidum mushrooms against various food-related pathogenic bacteria (Escherichia coli ATCC 25922, Listeria monocytogenes ATCC 7644, Salmonella enterica subsp. enterica serovar Enteritidis ATCC 13076, Staphylococcus aureus ATCC 2592, Vibrio parahaemolyticus ATCC 17802) and molds (Aspergillus parasiticus NRRL 2999 and Aspergillus parasiticus NRRL 465) were expressed as a diameter (mm) of the inhibition zone. The values of total phenolic content of different G. lucidum samples ranged from 2.35 to 10.46 mg GAE g(-1). The scavenging activity of DPPH radicals of G. lucidum samples did not show any significant difference for samples 2, 4, and 5. The same trend was observed between for ABTS+ results of these samples. The highest total phenolic content and antioxidative activity were observed in the sample 1. The extracts of different G. lucidum samples demonstrated statistically significant antibacterial activity against E. coli ATCC 25922. Regarding the antifungal activity of G. lucidum samples, there were not found any significant differences when compared different samples. The results demonstrated that G. lucidum can be used as a functional food ingredient to improve the bioactive properties of foods.