Water Quality Parameters


What is Phycoerythrin and What Does it Do?

Phycoerythrin is a light absorbing protein found in both Rhodophyta and cyanobacteria; or red and blue-green algae, respectively. Phycoerythrin is similar to phycocyanin - the protein responsible for creating a blue-green pigment in cyanobacterial algal blooms. Conversely, phycoerythrin is distinguished by its red hue and is characteristic of Rhodophyta blooms. Both belong to the chemical family phycobilin, the photosynthetic pigment which absorbs and directs energy from the sun to chlorophyll.

What is Phycoerythrin and What Does it Do?

Not quite like the oxygen we breathe, dissolved oxygen (DO) refers to the amount of oxygen present in a body of water. DO levels are one of the primary conditions that determine an aquatic environment’s ability to host flora and fauna, making it an essential indicator of water quality. The surrounding atmosphere and photosynthetic process of aquatic plants introduce DO into water systems, but living organisms like fish aren’t the only force depleting or consuming this DO. Bacteria also require DO to thrive, and in water with an overabundance of nutrients in the water, algal blooms can signal an upset in the ecological balance. With DO playing such a crucial role in the world’s water systems, accurately measuring DO levels is imperative for scientists who study aquatic ecosystems.

An overabundance of phycoerythrin can indicate a problematic nutrient imbalance within a water body. Harmful algal blooms associated with Rhodophyta are sometimes referred to as the toxic “red tide,” but phycoerythrin has also been a positive force in the field of water research. Fluorescent dyes like that which have been derived from phycoerythrin are crucial tools for ecological researchers. Other fields have begun investigating the pigment as an antioxidant for nutritional or medicinal uses.

Since chlorophyll fluorescence cannot be used to accurately determine cyanobacterial presence, analyzing phycobilin concentrations is essential for detecting, quantifying and monitoring cyanobacterial levels. Optical kits are used to quickly and easily detect this portion of the phytoplankton population.

How Do We Measure Phycoerythrin in Water?

Using a fluorescence method, PME’s Interchangeable C-FLUOR Logger and Fixed Cyclops-7 Logger are both capable of measuring phycoerythrin concentrations in waterbodies. The C-FLUOR logger boasts a measurement capacity ranging from 0 to 700 ppb (parts per billion) at a minimum detection limit of 0.1 ppb. The Cyclops-7 Logger also features a minimum detection limit of 0.1 ppb and can detect phycoerythrin concentration up to 750 ppb for projects studying heightened concentrations.

Products Measuring Phycoerythrin

Interchangeable C-FLUOR Logger

Fixed Cyclops-7 Logger