Differences in the emission of protein-like fluorescence between groups of Phytoplankton

Author

Puig López, Maria

Abstract

The PEGASO project consisted of expeditions to the Antarctic Ocean to quantify the emission of trace gases and aerosols from marine plankton. In this context, it can be said that one of the main sources of organic matter in water comes from marine phytoplankton, which accounts for more than half of the annual net primary production worldwide. Most nonphotosynthetic marine life is supported by organic matter obtained from phytoplankton, so understanding its composition is crucial to understanding marine ecosystems. Phytoplanktonic organisms emit different fluorescence signals and produce fluorescent organic compounds that can be found dissolved in water (FDOM) depending on many biotic and abiotic factors. The results of the PEGASO project indicated that the relationship between the amount of fluorescent organic matter and phytoplankton biomass depended on the dominant phytoplankton functional groups. The main objective of this thesis (TFG) is to test experimentally in monospecific cultures, if there are significant differences in the production of fluorescent compounds between species of different functional groups of phytoplankton (Diatoms and non-Diatoms).
To assess the effects of phytoplankton on particle and FDOM composition, we compared phytoplankton community composition with organic matter fluorescence measurements in filtered and unfiltered samples. Two types of fluorescent chemicals, humic substances (peaks A, C and M) and proteins (peaks B and T) were identified using spectrofluorometric and spectrophotometric techniques. The computer language R was used to analyse the data.
The results obtained reflect a relationship between the emitted fluorescence and the type of phytoplankton group, and the proportion of the total fluorescence signal that is attributable to bacteria, phytoplankton and dissolved organic matter, of each phytoplankton species, was also calculated.

Director

Auset Vallejo, María
Marrassé, Cèlia; Cabrera, Miguel

Degree

IQS SE - Undergraduate Program in Biotechnology

Date

2022-09-18