Evaluation of sample shipping, handling, and storage on algal pigments (chlorophyll a and phycocyanin)
Citation:
Shivers, S., J. Hollister, AND J. Stankoski. Evaluation of sample shipping, handling, and storage on algal pigments (chlorophyll a and phycocyanin). ASLO 2024, Madison, WI, June 02 - 07, 2024.
Impact/Purpose:
Cyanobacteria are found naturally in freshwater ecosystems and can form blooms under favorable conditions. These harmful algal blooms (cHABs) may be toxic and can affect human and environmental health. Chlorophyll and phycocyanin are widely used indicators of cHABs and understanding how handling and holding times affect degradation of these pigments during storage are needed in order to monitor cHABs more effectively.
Description:
Large scale (i.e. continental United States) aquatic resource surveys often collect samples and ship to a centralized processing laboratory. The rigors and chosen methods of shipping and handling as well as holding time could impact the integrity of algal pigments. This study examined the effects of a variety of simulated handling approaches and holding times on the degradation of chlorophyll and phycocyanin. An equal mixture of two green algae and two cyanobacteria cultures were filtered onto 370 GF/F filters and were assigned to treatments (five replicates per treatment). Treatments were used to evaluate holding time effects on filters stored at -20 °C, placed on or sandwiched between ice in a shipping cooler, and number of days in the shipping cooler. Pigments were extracted using a solvent-based extraction (90% acetone for chlorophyll a and 50 mM phosphate buffer for phycocyanin) and analyzed using a Turner Trilogy fluorometer. Preliminary analysis indicated a 15% loss of chlorophyll a and a 375% increase in phycocyanin after 60 days of holding at -20 °C. No significant differences between handling treatments were observed for chlorophyll a, whereas significant decreases were observed for all phycocyanin handling treatments. These results indicate that chlorophyll a on filters can be held with minimal loss for 60 days before analysis, and shipping and handling does not affect pigment degradation. Conversely, phycocyanin on filters were strongly affected suggesting that more research is needed to explain the increases during storage as well as the losses during shipping.
