Growth and lipid production of Rhodotorula glutinis R4, in comparison to other oleaginous yeasts

Abstract

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. Additionally, the production of these lipids starts at the end of the exponential growth phase and is more intense during the stationary phase.

Coupling azo dye degradation and biodiesel production by manganese-dependent peroxidase producing oleaginous yeasts isolated from wood-feeding termite gut symbionts

“…The highest values of biomass (13.28 ± 0.57 to 15.78 ± 0.45 g/L), lipid production (4.51 ± 0.88 to 7.10 ± 0.85 g/L), lipid content (33.96 ± 5.72 to 47.25 ± 1.84%, w/w), Y L/x (0.340 ± 0.07 to 0.473 ± 0.03 g/g), Y x/s (0.40 ± 0.005 to 0.50 ± 0.03 g/g), Y L/s (0.17 ± 0.02 to 0.23 ± 0.01 g/g), Q x (0.10 ± 0.007 to 0.15 ± 0.004 g/L/h) and Q L (0.04 ± 0.005 to 0.08 ± 0.003 g/L/h) were reached by the oleaginous yeast strains Meyerozyma caribbica SSA1654, Meyerozyma guilliermondii SSA1547, Debaryomyces hansenii SSA1502, and Vanrija humicola SSA1514 (Table 1 ). Our findings are in agreement with those reported by Maza et al [ 54 ] who found that Rhodotorula glutinis R4, Rhodotorula toruloides Y-1091, Rhodotorula toruloides Y-6987, and Rhodotorula toruloides Y-6985 revealed the highest values of biomass (14–16 g/L), lipid production (6.8–7.3 g/L), lipid content (43.9–48.9%, w/w), Y L/x (0.45–0.50 g/g), Y x/s (0.40–0.47 g/g), Y L/s (0.18–0.22 g/g), Q x (0.119–0.134 g/L/h) and Q L (0.057–0.061 g/L/h). On the other hand, Candida viswanathii Y-E4 showed the highest lipid yield (3.55 g/L).…”

“…As depicted in Table 2 , various other oleaginous yeast genera, such as Cryptococcus , Cyberlindera , Candida , Cystobasidium , Rhodotorula , Rhodosporidium , and Yarrowia , have been reported to have comparable values of biomass, lipid content and lipid productivity in case of glucose or biomass waste used as a carbon source. Meyerozyma caribbica SSA1654, isolated from termite gut symbionts, showed higher lipid productivity and comparable with Rhodotorula toruloides Y-1091 [ 54 ], Rhodotorula glutinis R4 [ 54 ], Candida viswanathii Y-E4A [ 56 ], Cystobasidium oligophagum JRC1 [ 57 ], Rhodosporidium kratochvilovae HIMPA1 [ 58 ], Cryptococcus curvatus [ 59 ] , and Rhodosporidium toruloides Y4 [ 60 ].…”

Advanced mono‐ and multi‐dimensional gas chromatography–mass spectrometry techniques for oxygen‐containing compound characterization in biomass and biofuel samples

“…An oleaginous feedstock is generally used for the production of biodiesel and jet fuel. Low‐quality lipids are preferred, such as (i) crude vegetable oils (soybean, palm, rapeseed, and sunflower); (ii) used vegetable oils; (iii) wasted animal fats; (iv) non‐edible oils [16–19]. Currently, algae and marine organisms have been more intensively investigated as a source of TGs [20–23].…”

Levaduras adaptadas al frío: el tesoro biotecnológico de la Antártica

“…La Antártica posee una fuente importante de levaduras oleaginosas, con adaptaciones que permiten acumular cantidades considerables de lípidos con interés biotecnológico a temperaturas entre los 15 y 25 °C (Rossi et al, 2009;Amaretti et al, 2010;Viñarta et al, 2016). Recientemente, se reportó que algunas levaduras aisladas del suelo de la Antártica contienen un alto porcentaje de ácido linoleico (omega-6) y oleico (omega-9), sugiriendo que estos microorganismos podrían tener un uso potencial en la producción de lípidos con valor comercial (Villarreal et al, 2018;Maza, Viñarta, Su, Guillamón & Aybar, 2020). Entre las levaduras oleaginosas de la Antártica, destacan las especies pertenecientes al género Rhodotorula, las cuales son excelentes productoras de ácidos grasos en forma de TAGs (Tabla II).…”

“…Entre las levaduras oleaginosas de la Antártica, destacan las especies pertenecientes al género Rhodotorula, las cuales son excelentes productoras de ácidos grasos en forma de TAGs (Tabla II). De hecho, ya se ha considerado que los TAGs de algunas cepas de Rhodotorula podrían resultar de gran utilidad como materia prima alternativa para la producción de biodiésel (Viñarta et al, 2016;Viñarta, Angelicola, Nieuwenhove, Aybar & de Figueroa, 2020;Maza et al, 2020). A pesar de que el género Rhodotorula se encuentra en varios ambientes, existen pocos estudios comparativos entre especies psicrofílicas y/o psicrotolerantes provenientes de distintos hábitats.…”