Factors Essential for Optimzing Solid Waste Degradation and Recycling Using Edible White Rot Fungi

Edible white rot fungi (EWRF) have been proposed for solid waste processing involving degradation of the lignocellulosic material and further recycling of food wastes and astronaut biosolids. Use of EWRF in solid waste processing is advantageous in that an edible product, the mushroom, is produced that adds variety to the restrictive diet of the astronaut during extended crewed missions. To optimize the efficiency of EWRF, key parameters (strains, N source, cropping pattern, growth medium/substrate amendment) controlling the biological process were examined under laboratory conditions. Various strains of Lentinula edodes and Grifola frondosa were evaluated in artificial culture media amended with human biosolid or food waste. Mycelial growth in strains of Pleurotus ostreatus and Lentinula edodes were measured on single and paired crop substrates. Enhancement of fungal growth by enriching the medium with KNO\d3, NH\d4Cl and urea and incorporation of solid thermophilic aerobic reactor (STAR) sludge in rice straw, as nitrogen sources, was determined. Significant growth differences were observed between G. frondosa strains in media added with either KNO\d3 or NH\d4Cl sources of nitrogen. P. ostreatus \u27Grey Dover\u27 was most prolific in growth and mushroom production in various crop residues. The use of EWRF may be a cost-effective way to accomplish solid waste processing in an ALS system that requires low-cost technologies applicable to the reduction of Equivalent System Mass (ESM), a major requisite for long- term space exploration or habitation