Das Lehrgebiet BioVT veröffentlicht zusammen mit der Tanta University (Ägypten) und dem Fraunhofer IGB (Stuttgart) in der Zeitschrift „Marine Drugs“ den Artikel „Characterization and Cytotoxic Activity of Microwave-Assisted Extracted Crude Fucoidans from Different Brown Seaweeds”.

Microwave-assisted extraction (MAE) is recognized as a green and relatively novel method for extraction of natural products. The current research aimed to explore the MAE for fucoidans extraction from different brown seaweeds, including Fucus vesiculosus, F. spiralis, and Laminaria saccharina. Following several solvent-extraction pre-treatment steps and MAE optimization, the algal biomasses were extracted in a ratio of 1:25 in 0.1 M HCl containing 2 M CaCl₂ for 1 min before neutralization and precipitation with three volumes of ethanol. The results showed that L. saccharina’s fucoidan was different from the others, regarding the highest sugar content reached 0.47 mg glucose equivalent/mg extract and the lowest fucoidan content and sulfation degree at 0.09 mg F. vesiculosus fucoidan equivalent/mg extract and 0.13, respectively. Moreover, these findings were confirmed by tentative structural elucidation based on Fourier-transform infrared spectrometry (FT-IR) which showed also different spectrum compared with other fucoidans. However, the MAE enhanced melanoidins formation in products, which was confirmed by the intense band at 1420 cm^-1. Interestingly, the results of monomeric composition showed that fucoidan extract by MAE from F. vesiculosus belonged to sulfated galactofucans which are known for their potential bioactivities. Furthermore, the cytotoxic activity of the four fucoidans in concentrations ranging from 4.9 g/mL to 2.500 µg/mL was investigated and correlated with the chemical characterization showing that F. vesiculosus_MAE fucoidan was the most potent and safest. The current research revealed the chemical heterogeneity of fucoidans with regard to taxonomical class and used greener extraction method of fucoidans from marine sources toward the achievement of the UN sustainability goals.

Zayed, A.; Finkelmeier, D.; Hahn, T.; Rebers, L.; Shanmugam, A.; Burger-Kentischer, A.; Ulber, R.; Characterization and Cytotoxic Activity of Microwave-Assisted Extracted Crude Fucoidans from Different Brown Seaweeds. Mar. Drugs 2023, 21, 48. https://doi.org/10.3390/md21010048