Increasing production of β-carotene from rhodotorula glutinis by high hydrostatic pressure

Rh. glutinis RG5 high-producing β-carotene was treated by ultra high pressure (UHP) of 100-500 MPa for 10-30 min. The shape of the survival curve was saddle after 10 minutes of treatment, which shows that the result of UHP treatment maybe a cumulation of many biological effects. The biomass of mutant RG5-3(obtained by 250 MPa for 10 min) was decreased by 9.25% related to the untreated RG5, but its β-carotene content was increased by 68.60% compared to RG5,and its genetic quality was proved to be stable by experiments. The DNA fragments cut by Hind III and BamH I were different, and this result proved that UHP made Rh. glutinis RG5 both changed in exterior characters and in nucleic acid level.