Bioconversion of agro wastes for the cultivation of the culinary-medicinal lion's mane mushrooms Hericium erinaceus (Bull.: Fr.) Pers. and H. laciniatum (Leers) Banker (Aphyllophoromycetideae) in Taiwan

Four different agro wastes, that is, rice hull, rice straw, sugarcane bagasse, and soybean dregs, were used to partially replace the sawdust of substrate components for the cultivation of Hericium erinaceus and H. laciniatum in order to explore their influence on biological efficiency, bioconversion rate, and yield. Among 10 experimental substrates, the biological efficiencies of those with the addition of 250 g kg-1 or 500 g kg-1 (dry wt) of sugarcane bagasse were 78.1% or 80.4% for H. erinaceus and 74.8% or 77.5% for H. laciniatum, respectively, whereas that of the control was 80.7% or 76.7% in the second flush. Both species of Hericium displayed higher cellulolytic and ligninolytic capabilities in the two above-mentioned substrates than in other experimental substrates during cultivation, and the bioconversion rates of the substrates that had formed fruiting bodies were near that of the control. The response surface methodology (RSM) was used to determine the optimal conditions, including temperatures, inoculation levels, aeration conditions, and equilibrium relative humidity (ERH), for the cultivation of the two species of Hericium on a substrate containing 500 g kg^-1 sugarcane. The highest yields and biological efficiencies of these mushrooms were obtained by cultivation at 23°C, inoculation level of 30-mg dry mycelium weight, no-forced aeration, and 90% ERH. The results showed that it is feasible to use some agro wastes to partially replace sawdust in the cultivation of the two species of Hericium. H. erinaceus exhibited higher biological efficiency and yield than H. laciniatum.