Your morning multi-vitamin may not only help you maintain your health, it may also be essential for marine life. MSRC graduate student Caterina Panzeca is investigating essential trace organic growth factors – specifically vitamins B1 and B12 – of marine phytoplankton to determine how they influence production and species composition. She explained that most phytoplankton need an outside source of B complex vitamins, often from bacteria, and different phytoplankton species may require different complements of B vitamins.
Parts of the Southern Ocean surrounding Antarctica are characterized by low biomass and production despite high levels of nutrients. B vitamins play an important role in phytoplankton growth and one of the goals of Panzeca’ s research is to better understand the marine cycling of these vitamins in low production areas. On a recent month-long Antarctic cruise on board the Spanish research vessel BIO Hesperides , thirty-knot winds, 8 to 10 m seas. and a near dip in the Weddell Sea did not deter Panzeca from collecting the water samples to initiate this work The project builds on work from another MSRC Ph.D. student, Mussie Okbamichael, who worked to develop the water preconcentration and vitamin analytical methods. MSRC professors Sergio Saliudo-Wilhelmy and Gordon Taylor are coprincipal investigators on the three-year effort funded by the National Science Foundation.
In addition to the field sampling, Panzeca also worked on two sets of shipboard experiments. Fertilization experiments were conducted by incubating seawater with iron, B-vitamins, or a combination of both, in order to evaluate differences in productivity based on chlorophyll concentrations and bacterial composition. A second set of experiments with krill determined if their excretions contribute to productivity.
In order to form a more complete picture of B vitamin cycling in the ocean, Panzeca will be spending much of the next two months at sea surveying different marine environments. In April, she will join other MSRC researchers on the Center’s R/V Seawolf sampling coastal environments from New York’s East River to the race in eastern Long Island Sound. In May, she will board the R/V Seward Johnson in the Azores on a cruise of the North Atlantic that concludes in Iceland. The main objective of this cruise is to follow a phytoplankton bloom and measure changing vitamin concentrations throughout. Panzeca concluded, “Preliminary results (from the Antarctic) are promising and show that chlorophyll concentrations in incubations spiked with vitamins B1 and B12 increased over time relative to unfertilized controls. I’m looking forward to further investigation and future cruises.”