Species disparity response to mutagenesis of marine yeasts for the potential production of biodiesel

Biotechnology for Biofuels

Thomas Breuck¹  Saloua Sadok²  Boutheina Bessadok³  Andrea Santulli⁴ 

[1] 0000000123222966, grid.6936.a, Fachgebiet Industrielle Biokatalyse, IBK Technische Universität München, Lichtenbergstraße 4, 85748, Garching, Germany;Blue Biotechnology and Aquatics Bioproducts Laboratory (B3Aqua), Institut National des Sciences et Technologies de la Mer – INSTM-Annexe La Goulette, 60 Port de Pêche, 2060, La Goulette, Tunisia;Blue Biotechnology and Aquatics Bioproducts Laboratory (B3Aqua), Institut National des Sciences et Technologies de la Mer – INSTM-Annexe La Goulette, 60 Port de Pêche, 2060, La Goulette, Tunisia;0000 0001 2156 2481, grid.424653.2, Institut National Agronomique de Tunisie (INAT), 43 Avenue Charles Nicolle, 1082, Tunis, Tunisia;Consorzio Universitario della Provincia di Trapani (CUPT), Lungomare Dante Alighieri, 91016, Casa Santa, TP, Italy;

关键词: Oleaginous yeast;    Lipid;    Fatty acid;    Biomass;    Biodiesel;    Mutagenesis optimization;    Ethyl methanesulfonate;   

DOI  :  10.1186/s13068-019-1459-y

来源: publisher

【 摘 要 】

BackgroundAmong the third-generation biodiesel feed stock, oleaginous marine yeasts are the least studied microorganisms for such purpose.ResultsWild strains yeasts were isolated from various Tunisian marine sources including fish waste (Candida tenuis CtTun15, Debaryomyces hansenii DhTun2015, Trichosporon asahii TaTun15 and Yarrowia lipolytica YlTun15) and seawater (Rhodotorula mucilaginosa RmTun15). Following incubation with ethyl methanesulfonate (EMS: 75 mM) for various periods of time (T15, T30, T45, T60 min), the cell viability of these strains responded differentially according to yeast species. For instance, mutated CtTun15 did not survive after 30 min of EMS treatment; higher resistances were observed in DhTun2015 (45 min), in YlTun15, RmTun15 and in TaTun15 (60 min) but with significant decreased cell viabilities (survival rate: 6.02, 3.16, 11.22, 11.58, 7.70%, respectively). For all surviving mutated strains, the optima of biomass and lipid yields were detected after 96 h in YPD culture; but derived from strains submitted to different period of EMS incubation. In most mutated strains, the maximum biomass (BP) and lipid (LP) productivities coincided and were observed after 30 min of EMS incubation. Only CtTun15 showed different optima of BP and LP (after 30 min and 15 min, respectively). The fatty acids (FA) compositions considered essential in the prediction of biodiesel criteria; were highly affected by EMS mutagenesis. Essentially, 30- and 45-min EMS incubation induced the highest levels of PUFA and MUFA in YlTun15, RmTun15 and TaTun15 with non-significant differences in the different times. However, CtTun15 and DhTun2015 mutant strains responded differently, with the highest levels of MUFA observed following 15 and 45 min; and that of PUFA after 30 and 45 min, respectively.ConclusionThe methyl-esterification of FA from the three mutated yeast strains (30 min—YlTun15, RmTun15 and TaTun15) yielded biodiesel with physical proprieties consistent with the International Standard System. However, investigations are needed for up-scaling biodiesel production.

【 授权许可】

CC BY