Single cell oil production from a newly isolated Candida viswanathii Y-E4 and agro-industrial by-products valorization

Abstract

Microbial lipids have drawn increasing attention in recent years as promising raw materials for biodiesel and added-value compounds production. To this end, new oleaginous yeast, Candida viswanathii Y-E4 was isolated, characterized and used for single cell oil (SCO) production. Physiologic and nutritional parameters optimization was carried out for improved biomass and lipid production. Y-E4 strain was able to use a wide range of substrates, especially C5 and C6 sugars as well as glycerol and hydrophobic substrates. The fatty acid profile analysis showed that oleic acid was the main component produced using different substrates. Batch and fed-bath fermentation were conducted using glucose as carbon source. Lipid production rate is twice higher in fed-batch culture providing a lipid content of 50 % (w/w). To minimize the SCO production cost, C. viswanathii Y-E4 was evaluated for its capacity to use different agro-industrial by-products for microbial oil production and changes in the fatty acid profile were monitored.

Isolation, identification and screening of yeasts towards their ability to assimilate biodiesel‐derived crude glycerol: microbial production of polyols, endopolysaccharides and lipid

“…In most cases, yeast strains performing the previously mentioned conversions (Gly conversion into polyols or SCO) are either mutants or are wild‐type strains originated from official culture collections (Koganti et al ; Tomaszewska et al ; Koganti and Ju ; Mirończuk et al ; Uprety et al , b). Although, in the last years there is a continuous growing interest regarding the potential of using natural new yeast isolates from different environments which may owe important attributes such as genetic stability, environmental adaptation and biotechnological characteristics that maybe used to different applications (Spadaro and Gullino ; Gil‐Serna et al ; Liu et al ; Ayadi et al , ; Arous et al ; Maina et al ). Moreover, concerning several types of fermentation processes (i.e.…”

Utilization of Wheat Bran Acid Hydrolysate by Rhodotorula mucilaginosa Y-MG1 for Microbial Lipid Production as Feedstock for Biodiesel Synthesis

“…Cultivation of the yeast using synthetic media for lipid production was in 0.5 L Erlenmeyer flasks containing 100 mL of culture. e synthetic medium composition was the same as described in our previous work [23] e carbon sources were commercial sugars such as glucose, xylose (alone or in mixtures), arabinose, sucrose, lactose, and polyol (glycerol). Culture samples were withdrawn regularly, and at the end of fermentation, the yeast cells were centrifuged at 3000 ×g for 5 min and harvested for the biomass determination and lipid extraction.…”

“…Besides glucose, other substances like disaccharides, polyols, and hydrophobic substrates could also serve as substrates for single cell oil production by oleaginous yeasts [34]. In addition, the fatty acids profile of accumulated lipids has been shown to be largely dependent on the nature of the carbon source used [23] which will determine the potential application of these lipids. To this end, the effect of carbon sources on cell growth, lipids accumulation, and relative fatty acids composition of R. mucilaginosa Y-MG1 was investigated and the results are shown in Table 1.…”

“…Lipid production was improved only in 3-liter bioreactor batch fermentation using glucose/xylose 2 : 1 combination [36]. On the other hand, the use of the glucose/ xylose combination as a carbon source significantly improves the lipids production by other oleaginous yeast strains such as C. viswanathii Y-E4 and T. cutaneum CTM-30125 (4.28 g/L and 4.58 g/L, respectively) [9,23]. Also, we noticed that Y-MG1 was able to assimilate and synthesize lipids when grown on glycerol (lipid content of 27.08%).…”

Optimization of parameters to increase the xylose reductase production from Candida tropicalis strain LY15 using corn cob as hemicellulose waste substrates

“…The optimization of the fermentation medium by one factor at a time (OFAT) is not only a time intense technique but also may lead to imprecise results and conclusions. This standard way of optimization is unable to detect the interaction amongst two factors responsible for upgraded enzyme production (Ayadi et al, 2016). Response surface methodology (RSM) a statistical approach helps to maximize the enzyme yield by designing limited tests for several parameters .…”