Bioemulsifier production by an oleaginous yeast Rhodotorula glutinis IIP30 (original) (raw)
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Bioemulsifier Production in Batch Culture Using Glucose as Carbon Source by Candida lipolytica
Applied Biochemistry and Biotechnology, 2001
The yeast Candida lipolytica IA 1055 produced an inducible extracellular emulsification activity while utilizing glucose at different concentrations as carbon source during batch fermentation at 27°C. In all glucose concentrations studied, maximum production of emulsification activity was detected in the stationary phase of growth, after pH reached minimal values. The bioemulsifier isolated was a complex biopolymer constituting proteins, carbohydrates, and lipids. The results obtained in this work show that the biosynthesis of a bioemulsifier is not simply a prerequisite for the degradation of extracellular hydrocarbon.
Lipid production for second generation biodiesel by the oleaginous yeast Rhodotorula graminis
Bioresource technology, 2012
The increasing cost of vegetable oils is turning the use of microbial lipids into a competitive alternative for the production of biodiesel fuel. The oleaginous yeast Rhodotorula graminis is able to use a broad range of carbon sources for lipid production, and is able to resist some of the inhibitors commonly released during hydrolysis of lignocellulosic materials. Using undetoxified corn stover hydrolysate as substrate, the yeast achieved a lipid productivity and lipid content of 0.21 g/L/h and 34% w/w, respectively. The corresponding results with crude glycerol as carbon source were 0.15 g/L/h and 54% w/w, respectively. Therefore, R. graminis appears to be a suitable candidate for fermentation processes involving renewable resources.► Rhodotorula graminis can use a broad range of carbon sources for lipid production. ► Yeast biomass with high lipid content can be obtained in fed-batch process. ► High lipid concentration and productivity can be obtained from sugars and glycerol. ► R. graminis can resist to inhibitors by the hydrolysis of lignocellulosic materials. ► R. graminis can be used to produce second generation biodiesel.
Growth and lipid production of Rhodotorula glutinis R4, in comparison to other oleaginous yeasts
J Biotechnol , 2020
Some Rhodotorula spp. have been characterized as oleaginous yeasts. Under certain culture conditions they can accumulate neutral lipids, which are mainly triglycerides (TAG). Microbial TAG that can be used as raw material for biodiesel synthesis are attractive for the biofuel industry. In this study, the ability to synthesize lipids of Rhodotorula glutinis R4, isolated in Antarctica, was compared with eight strains belonging to the genera Rhodotorula and Yarrowia with the aim of proposing a novel source of oils for biodiesel synthesis. All strains were cultured under nitrogen (N) limiting conditions and an excess of carbon (C) in the culture medium. We found that yeasts accumulated between 9-48.9 % (w/w) of lipids. Among them, R. glutinis R4 showed the highest growth (14 g L −1 , μmax 0,092 h −1) and lipid production (7 g L −1 ; 47 % w/w). Microbial oils produced by R. glutinis R4 are similar to vegetable oils, with 61 % of oleic acid, indicating that it is adequate for biodiesel synthesis. Our results demonstrate that biodiesel derived from R. glutinis R4 complies with international fuel standards ASTM D6751 and EN 14214. Therefore, this work demonstrates that Rhodotorula glutinis R4 is a novel and valuable source of microbial oils for biodiesel synthesis.
Isolation of a bioemulsifier from Candida lipolytica. Appl Environ Microbiol 48: 747-750
Applied and Environmental Microbiology
The yeast Candida lipolytica produced an inducible extracellular emulsification activity when it was grown with a number of water-immiscible carbon substrates. Negligible emulsification activity was produced by this yeast when it was grown with glucose as the carbon substrate. In hexadecane-supplemented cultures, emulsification activity was first detected after 36 h of growth, with maximum production after 130 h. A water-soluble emulsification activity was partially purified by repeated solvent extractions of the culture filtrate. This emulsifier, which we named liposan, was primarily composed of carbohydrate. Maximum emulsification activity was obtained when the ratio of hexadecane to liposan was 50:1. Maximum emulsification activity was obtained from pH 2 to 5. Liposan was heat stable to temperatures up to 70 degrees C, with a 60% loss in activity after heating for 1 h at 100 degrees C. Liposan effected stable oil-in-water emulsions with a variety of hydrocarbons.
Isolation of a bioemulsifier from Candida lipolytica
Applied and environmental microbiology, 1984
The yeast Candida lipolytica produced an inducible extracellular emulsification activity when it was grown with a number of water-immiscible carbon substrates. Negligible emulsification activity was produced by this yeast when it was grown with glucose as the carbon substrate. In hexadecane-supplemented cultures, emulsification activity was first detected after 36 h of growth, with maximum production after 130 h. A water-soluble emulsification activity was partially purified by repeated solvent extractions of the culture filtrate. This emulsifier, which we named liposan, was primarily composed of carbohydrate. Maximum emulsification activity was obtained when the ratio of hexadecane to liposan was 50:1. Maximum emulsification activity was obtained from pH 2 to 5. Liposan was heat stable to temperatures up to 70 degrees C, with a 60% loss in activity after heating for 1 h at 100 degrees C. Liposan effected stable oil-in-water emulsions with a variety of hydrocarbons.
Process Biochemistry, 2018
Lipid was produced by Rhodosporidiobolus fluvialis DMKU-SP314 from a mixture of low-cost substrates: sugarcane top hydrolysate (STH) and biodiesel-derived crude glycerol. The optimized lipid production medium for shaking flask cultivation contained STH supplemented with 59 g/L crude glycerol, 0.21 g/L soybean powder, 0.9 g/L (NH 4) 2 SO 4 , 0.4 g/L KH 2 PO 4 , 2.0 g/L MgSO 4 •7H 2 O and pH 6.1 (C/N ratio 60), while the optimal cultivation temperature was 28°C. Batch cultivation in a 2 L stirred-tank fermenter at an agitation speed of 300 rpm and an aeration rate of 2 vvm achieved the maximum lipid quantity of 18.2 g/L, which was 75.0% of dry biomass (24.3 g/L biomass), after 240 h of cultivation. These represent a 5.4-fold and 1.7-fold improvement in the lipid concentration and lipid content, respectively, compared to non-optimized shaking flask cultivation. Under optimal conditions, the lipid produced had a high monounsaturated fatty acid content (36.6% of oleic acid), which is suitable for biodiesel production. Thus, R. fluvialis DMKU-SP314 is capable of producing large quantities of lipid from low-cost raw materials in a process that can be readily scaled up for industrial production.
Energy, 2013
This study investigated the production of microbial lipids for biodiesel production and high-value carotenoids by Rhodotorula glutinis combined with the use of brewery wastewater as carbon source for three treatments: (raw wastewater) WW raw , (glucose supplemented raw wastewater) WW glu and a (synthetic sugar medium) WW synth . The collected brewery effluents showed high contents of sugars (maltose 24.34 g L À1 ; glucose 5.77 g L À1 ), but the low utilization of maltose led to a limitation of carbon in WW raw and WW glu . Since nitrogen was still available, carbon was channeled into cell growth instead of lipid formation, reaching an overall biomass production of 5.22 g L À1 , 7.38 g L À1 , and 9.55 g L À1 , respectively. Carotenoids were synthesized in all treatments with total average carotenoid contents between 0.6 and 1.2 mg L À1 and with high proportions of b-carotene (w50%) in the wastewater treatments. Suboptimal culture conditions (pH; aeration) have been identified as obstacles for higher lipid and carotenoid yields. Nevertheless, brewery wastewaters can be considered as carbon source for microbial fermentation, since they can be assumed to be an adequate source of nitrogen and other nutrients, whereas the utilization of maltose needs to be increased to achieve considerable amounts of lipid and carotenoid production.
Rhodotorula glutinis T13 as a potential source of microbial lipids for biodiesel generation
Journal of Biotechnology, 2021
Single cell oils (SCO) are a promising source of oils that could be exploited in different industrial areas. SCO for biodiesel production circumvents the controversy food vs. fuel, does not require large land areas for culture, and is independent of climate and seasonal variations, among other advantages in comparison to vegetable oils. In this study, a red yeast isolated from a mountain water source, identified as Rhodotorula glutinis T13, showed high potential for lipid production (40% w/w) with suitable growth parameters, yields, and fatty acids profile. Yeast lipids showed a high content of unsaturated fatty acids (56.44%; C18:1, C18:2), and the fuel properties (cetane number, iodine value, density, kinematic viscosity, etc.) of yeast oil analysed were in good agreement with international biodiesel standards. The results show that R. glutinis T13 can be used in the future as a promising microorganism for the commercial production of biodiesel.
New bioemulsifiers produced by Candida lipolytica using D-glucose and babassu oil as carbon sources
Brazilian Journal of Microbiology, 2003
Candida lipolytica IA 1055 produced extracellular biosurfactants with emulsification activity by fermentation using babassu oil and D-glucose as carbon sources. Natural seawater diluted at 50% supplemented with urea, ammonium sulfate, and phosphate was used as economic basal medium. The best results were achieved with the YSW-B2 medium, which contained urea, ammonium sulfate, and babassu oil and with YSW-B3 medium, which contained urea, ammonium sulfate, phosphate, and babassu oil, kept under fed batch fermentation for 60 hours with 5% of babassu oil. For the two media, the maximum specific growth rates were 0.02 h -1 and 0.04 h -1 ; the generation times were 34.6 h -1 and 17.3 h -1 , and the emulsification activities were 0.666 and 0.158 units, respectively. The molecules of these new bioemulsifiers were contituted of carbohydrates, proteins and lipids.
3 Biotech, 2017
Rhodotorula kratochvilovae (syn, Rhodosporidium kratochvilovae) SY89, an oleaginous yeast, isolated from Ethiopian soil, was grown under nitrogen-limited media. The capacity this with respect to biomass production, lipid yield and lipid content was evaluated. The influence of inoculum size, carbon sources, variations in glucose concentration, nitrogen sources, C/N ratio, pH, temperature, agitation, and aeration rate and incubation period were investigated. Inoculum size of 10% v/v, glucose as a carbon source at 50 g/L glucose, 0.50 g/L yeast extract and 0.31 g/L (NH4)2SO4, C/N ratio of 120, pH 5.5, incubation temperature of 30 °C, 225 rpm, 0.2 as aeration ratio and 144 h of incubation were found to be optimum conditions for lipid production. Then the yeast was grown in a batch bioreactor by combining the different optimized parameters together. Under the optimized conditions, the yeast gave maximum biomass (15.34 ± 1.47 g/L), lipid yield (8.60 ± 0.81 g/L) and lipid content (56.06 ± ...