Mass cultivation of the marine diatom Porosira glacialis: Method development and comparison of pigment composition in response to irradiance wavelenght

Abstract

In 2015, UiT The Arctic University of Norway and a local smelting plant initiated a project aiming to reduce the carbon footprint by mass cultivation of microalgae. The ability of the microalgae to directly capture industrially emitted CO2 and utilize wastewater as alternative nutrient sources to produce high value biomass, causes the bio-carbon recycling to represent both an environmental and economical feasible strategy. The produced microalgal biomass composes value-added products as lipids, proteins and pigments, and has the potential to ensure macronutrient quality as supplements in aquaculture fish-feed. The main goals of this thesis were to develop a method for pigment analysis and investigate the pigment composition in response to irradiance wavelength.

The polar diatom Porosira glacialis was cultivated under three different wavelength irradiances, red, blue and white light. Pigments were extracted from lyophilized algal biomass by utilization of a developed pigment extraction protocol and analyzed through HPLC-MS with positive ESI ionization. Data dependent acquisition (DDA) methods were used in order to create an in-house AMRT database, acquire identification information and determine relative pigment abundance. The identification and relative quantification were performed both manually and with the assistance of the software Compound Discoverer™.