Lipid production from sugar beet molasses under non-aseptic culture conditions using the oleaginous yeast Rhodotorula glutinis TR29

Evaluation of the process conditions for the production of microbial carotenoids by the recently isolated Rhodotorula mucilaginosa URM 7409

“…Similar behaviour was observed for the cell growth of Rhodotorula glutinis in a medium such as beet molasses supplemented with ammonium sulphate (Taskin et al, 2016).…”

“…Yeast extract and peptone were shown to be the variables with the greatest influence, with a negative effect on carotenoid production, followed by pH (positive effect). This inhibitory effect of the yeast extract and peptone can be explained by the excess of nitrogen source or a low C:N ratio, which limits the accumulation of carotenoids in oleaginous microorganisms, including the Rhodotorula strains (Taskin et al, 2016). The microorganismproducing carotenoids require minimal amounts of nitrogen, serving as maintenance for their development, allowing the excess carbon in the culture medium to be used for the synthesis of pigments (Spier et al, 2015), a fact observed in this work, for R. mucilaginosa, which requires smaller amounts of nitrogen.…”

“…Considering that the other variables were significant, such as malt extract (10 g/L) and glucose (30 g/L) and exerted little influence on carotenoid production, they were fixed at their highest level (+1), for a high C/N ratio. In short, the strategy adopted was to reduce the nitrogen sources to better absorb the excess of available carbon sources in the culture medium, as observed in other studies (Spier et al, 2015;Taskin et al, 2016).…”

Effect of carbon and nitrogen source concentrations on the growth and lipid accumulation of yeastTrichosporon oleaginosusin continuous and batch culture

“…Considerable savings in microbial lipid production could be achieved by using inexpensive agro and industrial residues for growing microorganisms and lipid accumulation. Oleaginous yeasts could be cultivated on different low‐cost substrates including waste glycerol from biodiesel production, lignocellulosic biomass (hydrolysates from corn stover, corn cobs and wheat straw), raw materials from the food industry (olive pomace oil, stearin, N‐acetylglucosamine from shrimp processing waste), wastewaters (cheese whey, wastewaters from confectionary industries, olive mill wastewater, palm oil mill effluent, and sewage sludge), food waste hydolysate, molasses (sugar cane molasses waste and sugar beet molasses), organic acids and waste spent yeast from the brewing industry . Considerable research work has been done on studying the effect of culture conditions as well as carbon and nitrogen sources impact on the growth and lipid synthesis in oleaginous microorganisms mostly during batch or fed‐batch culture .…”

Conversion of sugar beet residues into lipids by Lipomyces starkeyi for biodiesel production

“…Sugar beet re nery produces a huge amount of residues in the form of molasses and sugar beet pulp (SBP), whose worldwide production in 2018/2019 has been estimated to be about 65 and 4 million tonnes, respectively [10]. Molasses can be used as animal feed and as a feedstock for bioethanol production; its high carbon (mostly sucrose) and poor nitrogen content makes molasses also a promising substrate for microbial lipids, but its utilization requires the addition of external nitrogen sources [11][12][13][14]. SBP can be used as animal feed but it is considered a potential feedstock for microbial productions because the high fraction of carbohydrates (24-32 % hemicellulose, 22-30 % cellulose and 38-62 % pectin) [15,16] can promote microbial growth and the low lignin content (<2 %) can reduce the costs of pre-treatment, compared to most other lignocellulosic biomasses.…”