title: Improvement of ganoderic acid and Ganoderma polysaccharide biosynthesis by Ganoderma lucidum fermentation under the inducement of Cu2+.
abstract: The cell growth and total accumulation of bioactive metabolites were significantly improved by Cu(2+) addition during the submerged fermentation of medicinal mushroom Ganoderma lucidum. A mathematical model, constructed by response surface methodology combination with full factorial design, was applied to study the synergic effect of Cu(2+) addition concentration and addition time. The optimal Cu(2+) inducement strategy for the cell growth were different from those for the biosynthesis of ganoderic acid (GA) and Ganoderma polysaccharide. A multiple additions strategy of Cu(2+) by adding each 1 mM Cu(2+) on day 2, 6, 8 and 2 mM Cu(2+) on day 4 was developed to enhance total accumulation of GA and extracellular polysaccharides. The highest GA content reached 3.0 +/- 0.1 mg per 100 mg DW, which was increased by 76.5% and 33.9% compared with the control without Cu(2+) addition and the peak value predicted by the constructed mathematical model, respectively. While, relatively higher addition concentration of Cu(2+) (i.e., 5 mM) on the culture of day 4 led to higher content and total production of intracellular polysaccharides.
authors: Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei Provincial Key Laboratory of Industrial Microbiology, College of Bioengineering, Hubei University of Technology, Wuhan 430068, China. yajietang@hotmail.com
authors: Ya-Jie
authors: YJ
authors: Tang
authors: Li-Wen
authors: LW
authors: Zhu
mesh_terms: D000704:Analysis of Variance; D003300:Copper / Q000378:metabolism; D005285:Fermentation; D032902:Ganoderma / Q000737:chemistry* / Q000378:metabolism; D006538:Heptanoic Acids / Q000378:metabolism*; D008954:Models, Biological; D011134:Polysaccharides / Q000096:biosynthesis / Q000378:metabolism*; D013499:Surface Properties; D014315:Triterpenes / Q000378:metabolism*
chemical_list: D006538:Heptanoic Acids; D011134:Polysaccharides; D014315:Triterpenes; D003300:Copper