Biosynthesis of citric acid by Yarrowia lipolytica repeat-batch culture on ethanol

Abstract

After analysis of batch culture and identification of the ways for prolongation of citric acid active synthesis by yeast, repeat-batch (RB) cultivation was suggested. Yarrowia lipolytica strain RB cultivation was studied and optimal conditions for cultivation selected. It was shown that when applying RB cultivation, better results were obtained than for batch cultivation. The activity of the culture remained stable after cultivation for more than 700 h. Comparative analysis of enzyme activities confirmed the regularity of the effect described, as the activity of practically of all the enzymes participating in ethanol oxidation and citric acid biosynthesis remained stable over time during RB cultivation. Advantages of RB cultivation for the production of citric acid by yeast are discussed.

An Experimental Study on Citric Acid Production by Aspergillus niger Using Gelidiella acerosa as a Substrate

“…Further increase in incubation period does not enhance the citric acid production. It may be due to the age of fungus used and depletion of sugar contents in the culture broth [17]. Actually, the acid production starts with the initial stage idiophase (between 80 and 120 h) of fungal growth.…”

Optimization of Culture Conditions Using One-Factor-at-Time Methodology and Partial Purification of Amylase from Aspergillus niger of DTO: H5 under Solid State Fermentation

“…The reduction in yield may be because the culture has entered death phase of growth, reduction of nutrient (Arzumanov et al, 2000), the build-up of by-products and different toxins and also deterioration in the enzyme system (Sikander et al, 2003). This result is in contrast with the reports of Chimata et al, (2010), Farid and Shata (2011) and Puri et al, (2013), where other amylase producing fungi gave maximum yield at a period of 5 days.…”

Valorization of raw glycerol for citric acid production by Yarrowia lipolytica yeast

“…Batch-biosynthesis of citric acid has been studied extensively by many authors (Arzumanov et al 2000;Kamzolova et al 2003;Papanikolaou et al 2006;Moeller et al 2007). In batch cultures, carbon source concentrations usually range from 10 to 15%, since higher concentrations (200-300 g·L -1 ) of the substrate are likely to prolong the lag-phase, which has been observed in the processes of citric acid biosynthesis from glucose by the strain of Candida oleophila ATCC 20177 (Anastassiadis and Rhem, 2006).…”