Culture Systems Incorporating Heterotrophic Metabolism for Biodiesel Oil Production by Microalgae

Abstract

The feasibility of using various culture systems incorporating heterotrophic metabolism for biodiesel oil production was compared. Heterotrophic culture can be used to achieve high cell concentration, and depending on the strain and organic carbon source employed, the introduction of light (mixotrophic culture) can enhance cell growth and oil accumulation. However, mixotrophic cultures also face the problem of light limitation, and depending on the relative concentrations of the organic carbon source and light intensity, the interaction between the heterotrophic and photoautotrophic metabolic activities can have negative effects on cell growth and oil accumulation. Systems that separate the two metabolic activities in time or space, such as cyclic photoautotrophic-heterotrophic cultures, sequential heterotrophic-photoautotrophic cultures, and sequential photoautotrophic-mixotrophic cultures, can all be used to improve oil productivity. However, the effectiveness of each system depends on the strain of microalgae and other culture conditions.

Effects of Carbon Source on Growth Characteristics and Lipid Accumulation by Microalga <i>Dictyosphaerium</i> sp. with Potential for Biodiesel Production

“…Lipid accumulation was not dependent on the initial medium glycerol contents in the present study. In the heterotrophic cultivation of algae for lipids, it has been reported that increasing the carbon substrates concentrations leads to increase in lipid accumulation [9] [10]. In the present study, lipid accumulation seemed to be uniform irrespective of the initial medium glycerol level.…”

“…Not all oils are suitable for biodiesel production de novo. Ogbonna and McHenry [9] and Ogbonna and Moheimani [10] reported that oil quality of heterotrophically cultivated algal cells is better than those under photoautotrophic…”

Evaluation of Oil Producing Potential of a New Isolate—<i>Chlorella lewinii</i> SUB3545914 for Biodiesel Production under Heterotrophic Cultivation

“…Similarly, lipid accumulation in heterotrophic cultures was significantly higher than the values obtained in photoautotrophic cultures. This also supports dome previous reports[9] [12][13] [14]…”

“…[10] [11] [14] [15] [34]. Similarly, lipid accumulation in heterotrophic cultures was significantly higher than the values obtained in photoautotrophic cultures.…”

Integration of microalgal cultivation system for wastewater remediation and sustainable biomass production

“…There are many benefits of heterotrophic/mixotrophic cultures over photoautotrophic cultures. These include the use conventional bioreactors which are simpler and easier to scale up, elimination of light requirements, higher cell densities, which reduce the cost of harvesting the cells (Ogbonna and McHenry 2015). Owing due to requirement of low light intensity, some mixotrophic strains have reduced photoinhibition and growth rates are higher as compared to photoautotrophic and heterotrophic Pahl et al (2013)] cultures.…”