Mutant Yarrowia lipolytica strains producing citric acid from glucose

Citric Acid Production by Yarrowia lipolytica Yeast on Different Renewable Raw Materials

“…The mutant strain Y. lipolytica NG40/UV5 was obtained as described previously [9,24]. Chemicals, the manufacturer of the carbon sources, and their characteristics were presented in our published articles [7,9,15,17].…”

Enhancing citric acid production of Yarrowia lipolytica by mutagenesis and using natural media containing carrot juice and celery byproducts

“…It is known that the mutant citric acid producers display a low activity of aconitate hydratase, the enzyme transforming citric acid to isocitric acid in the cells (2). Most strains of Y. lipolytica grow very efficiently on acetate as sole carbon source (18).…”

“…It is reported that citric acid has been produced microbiologically in all of the developed countries. The annual world citric acid production is reported as 800,000 tons and increases annually by 5% (2). While Aspergillus niger is the primary organism used for citric acid production, the yeast Yarrowia lipolytica is also known to produce high yields of citric acid (3).…”

“…Since citric acid is an intermediate of energy metabolism, its concentration can rise to appreciable amounts under conditions of metabolic imbalances (2). As strategies to increase yield and reduce production cost, optimization of fermentation conditions, and obtaining hyper-producing mutants are of primary importance (1).…”

“…From the colonies analyzed, those with smaller size were selected predominantly (2). Those strains unable to grow in acetate medium or displaying a retarded growth on this medium were selected as potential mutant strains and the cultures of these strains on YM agar were used for making stock cultures and kept at 4 o C until use.…”