Use of Ganoderma lucidum grown on agricultural waste to remove antibiotics from water

Abstract

Antibiotic-rich effluents from farming and medical establishments into waterways pose a serious risk for antibiotics resistance, promoting a need for effective strategies of removal from the food chain and the environment. In this work, we show proof-of-concept laboratory-scale low-cost bioremediation experiments to remove antibiotics in synthetic wastewater. A white rot fungus, Ganoderma lucidum, was grown on biomass formed by agricultural waste from California (almond shells, cover crop stalks). Water containing or lacking Ganoderma lucidum was inoculated with twenty antibiotics from six different classes. The extent of antibiotic removal was measured at baseline and after 3 days with ultra-high pressure liquid chromatography coupled to tandem mass-spectrometry. The data were analyzed with a two-way repeated ANOVA for 17 antibiotic data sets meeting residuals' normality, and a mixed-effects model for 3 antibiotics that did not. Treatment with mycelial biomass for 3 days caused a statistically significant reduction, compared to the baseline, in the concentration of 3 quinolones and 1 sulfonamide. There were similar non-significant trends or neutral results in the other 16 antibiotics within those 3 days. Within the limitations of our work, our findings provide a first proof-of-concept on the potential to bioremediate certain antibiotics, particularly quinolones and sulfonamides, in synthetic wastewater and with repurposed agricultural waste.