돈분뇨를 이용한 버섯 균사체 생물전환 기술

Abstract

Bioconversion technology with utilization of high-strength organic wastes as resources for bioproducts was developed. Especially, swine wastewater contains high organic matter, animal nitrogen, and also malodorous compounds (Spoelstra, 1978). However, there are certain difficulties in dealing with swine manure because of the high proportion of suspended solids resistant to biological degradation (Beaudet, 1990). Consequently, it is necessary to find new methods to treating swine wastewater. One possible solution to this problem is to use this potential pollutant as a growth substrate for economically valuable products. The study for the fundamental improvement of bioconversion efficiency using statistical models and biotechnologies was performed. A novel approach to utilize swine wastewater by cultivating mycelia of the three mushroom Ganoderma lucidum, Hericium erinaceum, and Pleurotus ostreatus are described. A central composite in cube design for the experiments was used to develop empirical model providing a quantitative interpretation of the relationships among the three variables, which were substrate concentration, pH, and temperature. Response surface analysis was successfully applied to determine the optimal conditions where the maximal mycelial growth occurred for bioconversion of swine wastewater. The condition predicted to maximize the radial extension rate of G. lucidum (10.7 ± 0.4 mm/d) was determined to be pH 5.3, temperature 28.2oC, and substrate concentration 12.3g COD/L. The maximal radial extension rate (3.0 ± 0.1 mm/d) of H. erinaceum was determined under the condition of 12.1 g COD/L, pH 4.6, and temperature 25.7oC. In this manner, the condition determined as providing maximal mycelial growth rate of P. ostreatus was 10 COD g/L substrate concentration, pH 5.6, and temperature 27.0oC. Maximum radial extension rate under these conditions was estimated to be 11.8 ± 0.4 mm/d. The results of this study suggest that swine wastewater could be utilized as a growth substrate for the cultivation of mushroom mycelia enhancing to utilize this by-product of the livestock industry.