title: Optimization of the medium composition of a biphasic production system for mycelial growth and spore production of Aschersonia placenta using response surface methodology.
abstract: The culture media for mycelial growth and sporulation of the entomopathogenic fungus Aschersonia placenta were optimized using the response surface method (RSM). Interactions of medium components and the optimization of a biphasic production system were studied using Box-Behnken design (BBD) with three levels of three variables. Experimentation confirmed that the model developed based on RSM and BBD successfully predicted mycelia production (R(2) = 0.9336) and conidia production (R(2) = 0.9532). In the first phase, mycelial dry weight was highest (2.14 ± 0.17 g per 100ml of culture, mean±SE) when the concentrations (g/l) of glucose, vitamin B(6), and MgSO(4)·7H(2)O were 31.4, 11.5, and 0.64, respectively. In the second phase, conidia production was highest (9.31 ± 0.48 × 10(7)sporespercm(2)) after 18d of cultivation in the medium containing 33.8 g/l of millet, 1.11 g/l of KH(2)PO(4), and 0.37 g/l of MgSO(4). Mycelial and conidial yields were 3.6- and 10-fold greater, respectively, with the optimized media than with the non-optimized basal media. The results indicate that RSM and BBD methods are effective for increasing the production of A. placenta mycelia and conidia.
authors.affiliation: Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, PR China. junzhiqiu@126.com
authors.forename: Junzhi
authors.initials: J
authors.lastname: Qiu
authors.forename: Feifei
authors.initials: F
authors.lastname: Song
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Qiu
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Li
authors.forename: Xiong
authors.initials: X
authors.lastname: Guan
mesh_terms: D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism*; D005285:Fermentation / Q000502:physiology*; D006999:Hypocreales / Q000254:growth & development*; D008954:Models, Biological; D025282:Mycelium / Q000254:growth & development*; D010572:Pest Control, Biological / Q000379:methods; D013170:Spores / Q000502:physiology*
chemical_list: D003470:Culture Media