No abstract

Oleaginous microorganisms, such as yeast, fungi, microalgae and bacteria, represent a key segment of second generation feed‐stock materials and are considered to synthesize a wide range of industrially important chemical compounds. Oleaginous microorganisms possess a broad varieties of chemical compounds such as carotenoids, pigments, carbohydrates, chlorophyll, and storage‐material lipids. Oleaginous microorganisms have been recognized as promising sources for the synthesis of unsaturated, especially polyunsaturated fatty acids (PUFA). So far, a variety of high‐throughput screening methodologies (HTMs) have been employed for the development of bioprocessing of oleaginous microorganisms for sustainable production of industrially valuable compounds. Of HTMs, flow cytometry (FC) and sorters (FACS) have received substantial interest as better HTMs because of their ability to screen large numbers of cells within seconds, and interrogate and isolate living cells at single‐cell level. Forward and side scattering signals of FC are used to determine the physiological state of the cell while different channels available in the FC facilitate the detection of signals produced from fluorophores. Simultaneous measurement of physiological characteristics along with specific compound accumulation at single‐cell level enables the possibility of separating a particular phenotype with specific properties from a population. Different microbial strain development strategies in combination with FACS produced improved phenotypes with desired properties. This review first summarizes the FACS methodologies suitable for oleaginous microorganisms and the significant progress that has been achieved in oleaginous microorganisms using FACS, and highlights the important, advanced and future prospects of FACS methodologies that are suitable for the development of bioprocessing in oleaginous microorganisms. © 2018 Society of Chemical Industry

Symbiosis naturally provides an opportunity for microorganisms to live together by mutual or one-way benefit. In symbiotic relationships, the microorganisms usually overcome the limitations of being free-living. Understanding the symbiotic relationships of oleaginous microorganisms provides potential route for the sustainable production of microbial-based alternative fuels. So far, several studies have been conducted in oleaginous microorganisms for the production of alternative fuels. However, some oleaginous microorganisms require high quantity of nutrients for their growth, and high level of energy and chemicals for harvest and separation of lipid bodies. Symbiotic associations can successfully be applied to address these issues. Of symbiotic associations, lichens and selective species of oleaginous endosymbiotic mucoromycotina have received substantial interest as better models to study the evolutionary relationships as well as single-cell oil production. Construction of artificial lichen system composed of cyanobacteria and oleaginous yeast has been achieved for sustainable production of lipids with minimum energy demand. Recently, endosymbiotic mucoromycotina species have been recognized as potential sources for biofuels. Studies found that endohyphal bacterium influences lipid profiling in endosymbiotic mucoromycotina species. Studies on the genetic factors related to oleaginous characteristics of endosymbiotic mucoromycotina species are scarce. In this regard, this review summarizes the different forms of symbiotic associations of oleaginous microorganisms and how symbiotic relationships are impacting the lipid formation in microorganisms. Further, the review also highlights the importance of evolutionary relationships and benefits of co-culturing (artificial symbiosis) approaches for sustainable production of biofuels.