Bioprospecting marine plankton

Abstract

The ocean dominates the surface of our planet and plays a major role in regulating the biosphere. For example, the microscopic photosynthetic organisms living within provide 50% of the oxygen we breathe, and much of our food and mineral resources are extracted from the ocean. In a time of ecological crisis and major changes in our society, it is essential to turn our attention towards the sea to find additional solutions for a sustainable future. Remarkably, while we are overexploiting many marine resources, particularly the fisheries, the planktonic compartment composed of zooplankton, phytoplankton, bacteria and viruses, represents 95% of marine biomass and yet the extent of its diversity remains largely unknown and underexploited. Consequently, the potential of plankton as a bioresource for humanity is largely untapped. Due to their diverse evolutionary backgrounds, planktonic organisms offer immense opportunities: new resources for medicine, cosmetics and food, renewable energy, and long-term solutions to mitigate climate change. Research programs aiming to exploit culture collections of marine micro-organisms as well as to prospect the huge resources of marine planktonic biodiversity in the oceans are now underway, and several bioactive extracts and purified compounds have already been identified. This review will survey and assess the current state-of-the-art and will propose methodologies to better exploit the potential of marine plankton for drug discovery and for dermocosmetics.

Figure 1

Number of articles per keyword query by year (analysis done on 26 August 2013 using PubMed.gov).

Figure 2

Culturing methods for microalgae developed at Greentech. (a) “Bag” culture system, very efficient at producing biomass at a low cost in batches. From left to right: Red algae (two bags), Green algae (two bags), Green algae in optimal conditions for β-carotene production, hence the yellow color (two bags); (b) “Annula” photobioreactor where the artificial light source is inside the culture. This system is optimal for controlling culture conditions and mixing, which generally allows for the highest final biomass yield in batch cultures; (c) 2500 L “Tubular” photobioreactor. This system is best for continuous culture conditions while maintaining the bulk of the culture in exponential growth phase; (d) Bench photobioreactor used by Greentech for culture condition optimization; (e) Samples from a culture collection in liquid or solid media; (f) “Fermentor” culture system for heterotrophic microalgae growth.

Figure 3

From cultivable plankton strains to drugs on the market: A long-term adventure.