Seasonal variability of phytoplankton at Varna Bay (Black Sea)

• Published in: Phytochemical analysis Vol. 14; no. 4; pp. 245 - 250
• Main Authors: Moncheva, S, Gorinstein, S, Shtereva, G, Toledo, F, Arancibia, P, Booth, W.A, Goshev, I, Weisz, M, Trakhtenberg, S
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.07.2003
• Subjects: algae and seaweeds; Bacillariophyceae; biomass; Bulgaria; carbohydrate content; carbohydrates; Carbohydrates - analysis; Carbohydrates - isolation & purification; Dinophyceae; Electrophoresis; Electrophoresis, Polyacrylamide Gel; Fluorescence; phytoplankton; Phytoplankton - chemistry; Phytoplankton - growth & development; plant communities; plant extracts; plant proteins; Plant Proteins - analysis; Plant Proteins - isolation & purification; polyacrylamide gel electrophoresis; protein content; proteins; qualitative analysis; quantitative analysis; seasonal changes; seasonal variation; Seasons; fluorescence; Bulgaria; MED, Black Sea; MED, Bulgaria, Varna, Varna Bay
• ISSN: 0958-0344; 1099-1565
• DOI: 10.1002/pca.711

Intrinsic fluorescence and SDS‐PAGE analysis were employed to study the seasonal qualitative and quantitative changes of phytoplankton composition at Varna Bay (Black Sea). Variation in the maximum emission wavelength (λmax) of the phytoplankton proteins (398 nm in the summer and 340 nm in the spring) was observed. In addition, a decrease in fluorescence intensity, and a shift in λmax as a result of changes in phytoplankton protein stability, according to the season, was noted. Similarly, SDS‐PAGE analysis showed different protein patterns for each season, for example in summertime the major protein constituents were of 14, 37, 48 and 70 kDa, while in the springtime the sizes ranged between 38 and 48 kDa. In general, higher carbohydrate and protein contents correlated with larger phytoplankton biomass found during the summer. The dominant species, the Bacillariophyceae and Dinophyceae, were found to be present in the water body in an alternate pattern. All of these changes could be accounted for by the adaptation of the organism to seasonal variations that modify the sea environment at Varna Bay. Copyright © 2003 John Wiley & Sons, Ltd.