Effect of the ratio of (+) and (-) mating type of Blakeslea trispora on carotene production from cheese whey in submerged fermentation

The effect of the ratio of (+) and (-) mating type of Blakeslea trispora on carotene production from deproteinized hydrolysed whey in shake flask culture was investigated. Also, the inoculum ratio of the two mating types on the morphology of the microorganism and the relationship between morphological changes of the fungus and product formation were studied. The concentration of carotenes was significantly affected by the ratio of (+) and (-) mating type of B. trispora. A ratio of 1:10 up to 1:100 of (+) and (-) type was found to achieve the highest carotene yields. The optimum ratio of the (+) and (-) mating types for the maximum pigment production (175.0 mg/g dry biomass at 8 days of fermentation) was found to be 1:10. The carotene content in B. trispora consisted of beta-carotene, gamma-carotene, and lycopene. At the maximum concentration of carotenes the proportion of beta-carotene, gamma-carotene, and lycopene (as percent of total carotenes) was 80, 12, and 8%, respectively. B.trispora growing in submerged fermentation is able to develop complex morphologies which have been classified into three major groups: freely dispersed hyphae, clumps and pellets. These parameters are strongly influence the production of carotenes.