Assessment of fuel properties on the basis of fatty acid profiles of oleaginous yeast for potential biodiesel production

Abstract

A B S T R A C TOver the last decade, there has been a huge upsurge of interest in sustainable production of biomass-based biofuels to fulfill the existing energy demand and simultaneously reducing the environmental deterioration. Earlier, vegetable oils and animal fats were utilized for biodiesel production, but due to food crisis and environmental sustainability, renewable sources such as neutral lipid derived from microbes are gaining much attention for budding biodiesel industries. Among various types of microorganisms, oleaginous yeasts are more promising feedstock to accomplish the current demand of biodiesel production and utilize a large number of cost-effective renewable substrates for their growth and lipid accumulation. However, biodiesel obtained from oleaginous yeasts have certain restrictions regarding their commercial utilization due to their unstable fuel properties such as oxidative stability, cetane number, viscosity and low-temperature performance etc. Numerous articles have been published in the public domain describing the fatty acid profiles of oleaginous yeast as feedstock for biodiesel production. However, the evaluation of quality parameters of biodiesel obtained from oleaginous yeasts is still in infancy. Although there is a huge disparity in a number of papers published for biodiesel production yet the reporting performance on diesel engines need to be verified in details. In this review article, attempt has been made to assess the important biofuel properties on the basis of the fatty acid profile of oleaginous yeast. Thus this evaluation would provide a guideline to the biodiesel producer to improve the production plans related to feedstocks for oleaginous yeast, culture conditions and biodiesel blending.

Lipids from yeasts and fungi: physiology, production and analytical considerations

“…other hexoses, disaccharides, glycerol, polysaccharides, etc. ;Ratledge 1988;Aggelis 2011a, 2011b;Patel et al 2017a). Lipids produced by the above-men tioned micro-organisms, addressed also as single cell oils (SCOs), present a continuously increasing interest concerning aspects of both applied and basic research (Moreton 1988; Ratledge and Wynn 2002;Ratledge and Cohen 2008;Aggelis 2011a, 2011b;Xu et al 2013).…”

“…sugars, glycerol, etc.) are considered as potential and important candidates for the production of this lipid that would result in the generation of the second-generation lipid-based biofuels (Huang et al 2013;Meeuwse et al 2013;Xu et al 2013;Koutinas et al 2014a;Muniraj et al 2015a;Patel et al 2016Patel et al , 2017aQin et al 2017). It is evident that concerning the production of liquid biofuels with the aid of oleaginous micro-organisms, only the hydrophilic carbon sources should be used as substrates for this purpose; it would evidently not make sense to proceed to fermentation of a fatty substrate in order to create cellular lipid that would subsequently be converted into biofuel (biodiesel or renewable diesel), while the initial fat substrate could have already been directly converted into biofuel without the step of fermentation being implicated.…”

“…cheese whey, various fractions of molasses, solid waste streams containing carbohydrates like waste sugars and waste bread, expired juices, olive-mill wastewaters, wastewaters deriving from confectionary facilities, etc. ), low-molecular weight organic acid resources, equally deriving from several agro-industrial and agro-chemical processes and, finally, lignocellulosic sugars or hydrolysates or wastewaters containing these types of sugars (Huang et al 2013;Koutinas et al 2014a;Leiva-Candia et al 2014;Tsakona et al 2014Tsakona et al , 2016Arous et al 2016Arous et al , 2017Patel et al 2016Patel et al , 2017aPatel et al , 2017bQin et al 2017). It is noted that the removal of nontoxic and nonhazardous wastes materials derived from food-processing facilities (i.e.…”

Economic assessment of biodiesel production from wastewater sludge

“…It implied that the greatest contributor to the final cost was utilities followed by raw materials. It was different from other studies which reported that the cost was mainly from the raw materials (up to 50-70% of the total cost) (Madani et al, 2017;Patel et al, 2017;Živković et al, 2017). It would be due to that the lipid source in the study was wastewater sludge which was cost free.…”

“…In addition, without taking credit, the biodiesel production cost was 1.08 US $/kg (0.94 US $/L) with 17.07% from raw materials, 30.73% from equipment, 6.39% from labor, 0.96% from lab/QC/QA, 44.47% from utilities, and 1.38% from waste treatment. The cost was higher than the commercial biodiesel derived from soybean which was 0.92 US $/kg biodiesel (Patel et al, 2017). Compared to the biodiesel produce from the lipid directly extracted from the sludge (0.67 US $/kg biodiesel), the cost of biodiesel production from the lipid accumulated in the microorganism cultivated with sludge was higher.…”