Variation of substance content during growth cycle of cultured Ganoderma lucidum and its mechanism / 中草药

ABSTRACT

Objective: To study the variation of the substance content in the different fractions of matrix during the growth cycle of Ganoderma lucidum, and to explore the mechanisms by investigating the change regulation of extracellular enzyme activity in the matrix of G. lucidum. Methods: G. lucidum was adopted by bag cultivation with sterilized raw materials, the growth period was divided into eight stages, and the matrix was splided in four equal portions. The variation of the contents of total sugar, reducing sugar, water-soluble protein, and free amino acids in different fractions of the matrix was studied, and the variation of activities of lignin enzymes (laccase and manganese peroxidase), cellulase (carboxymethyl cellulase, hemicellulase, and filter paper enzyme), and acidic protease at different fractions of the matrix were studied in order to elucidate the mechanisms. Results: During the growth period of G. lucidum, the content of total sugar at different fractions of the matrix decreased, and the content of reducing sugar increased before the growth of primordium, then decreased after the growth of primordium. The contents of water-soluble proteins showed increasing tendency at different fractions of the matrix, and the content of amino acid decreased before sackful of mycelium, but increased during the stage of bud and reached the peak, then decreased again. The variation of laccase activity showed the shape of U, and the lowest activity was appeared in the primordium period. The activity of manganese peroxidase was slowly increased during vegetative growth period, and decreased after sackful of mycelium. The activities of cellulase enzyme and acid protease were totally increased. Conclusion: In the growth cycle of G. lucidum, the substance contents in different fractions of matrix present different change tendency with the growth and development of G. lucidum; The extracellular enzyme activity of G. lucidum could affect the content of substance in the matrix, and there is a certain correlation between the activity of extracellular enzyme and material content in matrix of G. lucidum.