Survival of the fattest

Abstract

Liquid fuels have excellent properties in terms of storage, logistics and energy density compared to gaseous fuels or electricity. A major disadvantage of liquid fuels is that a vast majority of them is derived from fossil resources. Currently, the consumption rate of fossil fuels by far outcompetes the natural production rate, resulting in elevated atmospheric CO 2 concentrations. Photosynthetic organisms (plants and algae) xate atmospheric CO 2 using solar energy. CO 2 consumption and emission would be balanced if liquid fuels would be derived from plants or algae. However, growing terrestrial plants for biofuel production means less agricultural land and fresh water remains available for food production. Microalgae can grow under marine conditions and outcompete terrestrial plants in terms of areal productivity. On the other hand, cultivation of microalgae introduces new challenges. Species control is, compared to terrestrial plants, much more difficult. Any cultivation system is prone to contamination by undesired algal species threatening stable production. In this study we show that we can overcome this hurdle by creating a selective environment. Our approach allows for large scale, stable production of biofuel precursors and is therefore a substantial step forward in the production of renewable fuels.

Starch productivity in cyclically operated photobioreactors with marine microalgae—effect of ammonium addition regime and volume exchange ratio

“…2). These findings are in line with the behaviour observed under freshwater conditions in previous work (Mooij et al 2013). The yield of biomass on starch during the dark period was 0.62± 0.19 mg X mg −1 starch (or 0.56±0.17 mg X mg −1 glucose).…”

“…Sustainable large-scale microalgae cultivation will therefore most likely involve the use of marine microalgae (Vasudevan et al 2012). Previously, we have described a cultivation strategy to enrich and sustain a community of storage compoundproducing freshwater algae based on the ecophysiological role of storage compounds (Mooij et al 2013). This strategy enriches microalgae with high levels of internal storage compounds, which make the overall process economically more interesting (Borowitzka 1992).…”

Gravimetric enrichment of high lipid and starch accumulating microalgae

“…Cultivation of microalgae in pure culture will require an aseptic process condition resulting in a high investment and operating cost. Such preparations present serious barriers to large scale application (Mooij et al 2013). In addition, even in specific environmental conditions such as high salinity for Dunaliella Salina cultivation, where contamination likelihood is low, strain evolution remains as a great threat, since mutated strains with higher growth rate are able to outcompete the desired strain leading to a drop in productivity (Mooij et al 2015).…”

“…Screening mixed culture based on ecological role of product, would be a good solution to overcome cultivation contamination risk (Mooij et al 2013). Exploring microbial diversity and operation in various conditions are the main advantages of using mixed culture under selective environment (Johnson et al 2009, Kleerebezem andvan Loosdrecht 2007).…”

“…Selecting an appropriate species of microalgae is the first and most important step through the whole process of production of storage compounds (Mooij et al 2013 andTalebi et al 2014). …”