Microbial biodiesel production: novel method of utilizing sago wastewater for lipid production using oleaginous yeast, Candida tropicalis ASY1

Abstract Background Crude glycerol as a promising feedstock for microbial lipid production contains several impurities that make it toxic stress inducer at high amount. Under stress conditions, microorganisms can accumulate l-proline as a safeguard. Herein, l-proline was assessed as an anti-stress agent in crude glycerol media. Results Crude glycerol was converted to microbial lipids by the oleaginous yeast Rhodosporidium toruloides CGMCC 2.1389 in a two-staged culture mode. The media was supplied with exogenous l-proline to improve lipid production efficiency in high crude glycerol stress. An optimal amount of 0.5 g/L l-proline increased lipid titer and lipid yield by 34% and 28%, respectively. The lipid titer of 12.2 g/L and lipid content of 64.5% with a highest lipid yield of 0.26 g/g were achieved with l-proline addition, which were far higher than those of the control, i.e., lipid titer of 9.1 g/L, lipid content of 58% and lipid yield of 0.21 g/g. Similarly, l-proline also improved cell growth and glycerol consumption. Moreover, fatty acid compositional profiles of the lipid products was found suitable as a potential feedstock for biodiesel production. Conclusion Our study suggested that exogenous l-proline improved cell growth and lipid production on crude glycerol by R. toruloides. The fact that higher lipid yield as well as glycerol consumption indicated that l-proline might act as a potential anti-stress agent for the oleaginous yeast strain.

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Engineering an oleaginous yeast Candida tropicalis SY005 for enhanced lipid production

Applied Microbiology and Biotechnology ◽

10.1007/s00253-020-10830-6 ◽

2020 ◽

Vol 104 (19) ◽

pp. 8399-8411

Author(s):

Atrayee Chattopadhyay ◽

Anuja Gupta ◽

Mrinal K. Maiti

Keyword(s):

Candida Tropicalis ◽

Oleaginous Yeast ◽

Lipid Production

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Microbial Lipid Production from Corn Stover by the Oleaginous Yeast Rhodosporidium toruloides Using the PreSSLP Process

Energies ◽

10.3390/en12061053 ◽

2019 ◽

Vol 12 (6) ◽

pp. 1053 ◽

Cited By ~ 11

Author(s):

Xiaozan Dai ◽

Hongwei Shen ◽

Qiang Li ◽

Kamal Rasool ◽

Qian Wang ◽

...

Keyword(s):

Corn Stover ◽

Oleaginous Yeast ◽

Lipid Production ◽

Rhodosporidium Toruloides ◽

Biodiesel Production ◽

Advanced Technology ◽

Lignocellulosic Materials ◽

Microbial Lipid ◽

Lipid Yield ◽

Microbial Lipid Production

Dry acid pretreatment and biodetoxification (DryPB) has been considered as an advanced technology to treat lignocellulosic materials for improved downstream bioconversion. In this study, the lipid production from DryPB corn stover was investigated by the oleaginous yeast Rhodosporidium toruloides using a new process designated prehydrolysis followed by simultaneous saccharification and lipid production (PreSSLP). The results found that prehydrolysis at 50 °C and then lipid production at 30 °C improved lipid yield by more than 17.0% compared with those without a prehydrolysis step. The highest lipid yield of 0.080 g/g DryPB corn stover was achieved at a solid loading of 12.5%. The fatty acid distribution of lipid products was similar to those of conventional vegetable oils that are used for biodiesel production. Our results suggested that the integration of DryPB process and PreSSLP process can be explored as an improved technology for microbial lipid production from lignocellulosic materials.

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Harnessing pongamia shell hydrolysate for triacylglycerol agglomeration by novel oleaginous yeast Rhodotorula pacifica INDKK

Biotechnology for Biofuels ◽

10.1186/s13068-020-01814-9 ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Kukkala Kiran Kumar ◽

Farha Deeba ◽

Sauraj ◽

Yuvraj Singh Negi ◽

Naseem A. Gaur

Keyword(s):

High Throughput Screening ◽

Oleaginous Yeast ◽

Lipid Production ◽

Cetane Number ◽

Nile Red ◽

Major Fatty Acid ◽

Biodiesel Production ◽

Microbial Lipid ◽

Dry Cell Weight ◽

Pre Treatment

Abstract Background To meet the present transportation demands and solve food versus fuel issue, microbial lipid-derived biofuels are gaining attention worldwide. This study is focussed on high-throughput screening of oleaginous yeast by microwave-aided Nile red spectrofluorimetry and exploring pongamia shell hydrolysate (PSH) as a feedstock for lipid production using novel oleaginous yeast Rhodotorula pacifica INDKK. Results A new oleaginous yeast R. pacifica INDKK was identified and selected for microbial lipid production. R. pacifica INDKK produced maximum 12.8 ± 0.66 g/L of dry cell weight and 6.78 ± 0.4 g/L of lipid titre after 120 h of growth, showed high tolerance to pre-treatment-derived inhibitors such as 5-hydroxymethyl furfural (5-HMF), (2 g/L), furfural (0.5 g/L) and acetic acid (0.5 g/L), and ability to assimilate C3, C5 and C6 sugars. Interestingly, R. pacifica INDKK showed higher lipid accumulation when grown in alkali-treated saccharified PSH (AS-PSH) (0.058 ± 0.006 g/L/h) as compared to acid-treated detoxified PSH (AD-PSH) (0.037 ± 0.006 g/L/h) and YNB medium (0.055 ± 0.003 g/L/h). The major fatty acid constituents are oleic, palmitic, linoleic and linolenic acids with an estimated cetane number (CN) of about 56.7, indicating the good quality of fuel. Conclusion These results suggested that PSH and R. pacifica INDKK could be considered as potential feedstock for sustainable biodiesel production.

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