The choice of the culture medium is an important factor for the mass production of mycelia in submerged cultures. The influence of liquid medium on the mycelial dry weight of Paecilomyces tenuipes was investigated in this study. The regression equation is expressed as Y=-1292.94187+17.78612X1+18.92425X2+2.11464X3-0.019375X1X2-0.006276X1X3+0.008177X2X3- 0.070169X1 2-0.292175X2 2-0.008818X3 2, where Y represents the value of the mycelial dry weight (g/L), X1 is the particle size of wood sawdust in liquid medium (mesh), X2 is the concentration of the wood sawdust in liquid medium, and X3 is incubation time (h). The medium was optimized using a response surface methodology, and the optimal medium contained 30 g of wood sawdust (140 mesh), 20 g of glucose, and 10 g/L of peptone. Under these conditions, the mycelial dry weight reached 38.1 g/L (actual value). The culture medium containing wood sawdust is simple and easy to use, highly efficient, and eco-friendly, and its effectiveness in large preparations of P. tenuipes mycelia with low material costs has been demonstrated.
The cultivation of Sparassis crispa in the beginning of the 2000s in South Korea, and the cultivar ‘Neowul’ bred in the Chonbuk Agricultural Research and Extension Service were registered first in 2016. However, there is no manual for the cultivation of Sparassis crispa, and therefore, there remains a big difference in its harvest rate across farms. Herein, we aimed to study the primordium formation conditions of Sparassis crispa ‘Neowul’ according to the medium pH, medium moisture content, and inoculum volume of liquid spawn and develop a stable production technology. We found the annual yield per bottle relating to the cultivation period, harvest rate, and the weight of fruiting body to be the highest at 363.6 g in the area cultivated at pH 3.8. However, it is thought that cultivation by adjusting the pH to 3.9±1 would be necessary for stable production, considering that at pH 3.6, the yield sharply reduced to 189.5 g. Moreover, the culture period was shorter at pH 4.0 compared with that at pH3.8, and the cultivation period at pH 4.0 was the same as that at pH 3.8. No significant difference in the weight of the fruiting body at different conditions was recognized. Additionally, it is difficult to regulate the pH precisely in practical applications in the farms. It is thought that 341.8 g Sparassis crispa will be produced per bottle annually if the medium moisture content is adjusted to 65%, liquid spawn inoculum volume is equivalent to 4% of the medium volume, and the humidity in the culture room is set to below 50%.
