Förderung der β-Carotinsynthese durch Licht bei Phycomyces blakesleeanus Bgff.

Abstract

Phycomyces blakesleeanus was cultured in permanent darkness, permanent white blue(< 550 nm) and red (> 550 nm) light. In blue and white light, the β -carotene content was three times as high as that achieved in permanent dark and permanent red light. This increased β -carotene content can also be achieved by exposing dark cultures to white light. Then the carotene synthesis rises increasedly after 30 min time lag. By adding streptomycin and chloramphenicol to the culture solution, the light induction of the β -carotene synthesis in dark cultures is completely inhibited. The increased β -carotene synthesis of light cultures as compared to dark cultures is also a function of different enzyme activity. For example, an enzymes system extracted from light cultures transforms about twice as much mevalonic acid to β -carotene than enzymes extracted from dark cultures. A succession of light induced formation of β -carotene is discussed.