Enhancement of Lipids and Carotenoids Produced in Phycomyces blakesleeanus by Different Genetic Tools

摘要

The Phycomyces blakesleeanus strain used in this work was light yellow fungus and (-) sexual type. It was excreted total lip-ids; 5.5 g/l in emerged culture and 23.5 g/l in intracellular. It also was excreted carotenoid (Phytoene) 310 mg/l in emerged culture and 600 mg/l in intracellular, while main carotenoid (Carotene) was 380 mg/l in emerged culture and 750 mg/l in intracellular. After mutagenic treatment with different concentrations of Acriflavine (Ac); 100, 200 and 300 μg/ml., all selected mutants have been opposite sexual type (+). They were selected depends on yellow colour as a visible variation. In addition, the mutants included variable morphological and biochemical requirement e.g., leucine, lysine and asparagine. The results of lipids and carotenoid production showed that, there are correlation between dark colours and high production of them. On the other hand, there are no correlation between any of the obtained biochemical mutants and production capacity. Furthermore, there is positive correlation between production and positive mating type. The normal fusion between the two different mating types resulted in limited increasing in the production of both lipids and carotenoid. However, the protoplast fusion resulted in high production capacity of both lipids and carotenoid. An evidence for genetic changes is obtained by RAPD-PCR. The comparison between polymorphic fragments amplified by PCR for opposites mating type parents and fusants indicated different patterns, i.e different size of fragments.