The ocean contains ice nucleating substances (INSs), some of which can be emitted to the atmosphere where they can influence the formation and properties of clouds. A possible source of INSs in the ocean is exudates from sea-ice diatoms. Here we examine the concentrations and properties of INSs in supernatant samples from dense sea-ice diatom communities collected from Ross Sea and McMurdo Sound in the Antarctic. The median freezing temperatures of the samples ranged from approximately -17 to -22 °C. Based on our results and a comparison with results reported in the literature, the ice nucleating ability of exudates from sea-ice diatoms is likely not drastically different from the ice nucleating ability of exudates from temperate diatoms. The number of INSs per mass of DOC for the supernatant samples were lower than those reported previously for the sea surface microlayer and bulk sea water collected in the Arctic and Atlantic. The INSs in the supernatant sample collected from Ross Sea were not sensitive to temperatures up to 100 °C, were larger than 300 kDa, and were different from ice shaping and recrystallization inhibiting molecules present in the same sample. Possible candidates for these INSs include polysaccharide containing nanogels. The INSs in the supernatant sample collected from McMurdo Sound were sensitive to temperatures of 80 and 100 °C and were larger than 1000 kDa. Possible candidates for these INSs include protein containing nanogels.
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Int J Biol Macromol
January 2025
College of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310014, China; Zhejiang Key Laboratory of Green, Low-carbon and Efficient Development of Marine Fishery Resources, Hangzhou 310014, China; National R&D Branch Center for Pelagic Aquatic Products Processing (Hangzhou), Hangzhou 310014, China. Electronic address:
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Department of Biochemical Engineering, School of Chemical Engineering and Technology, State Key Laboratory of Synthetic Biology, Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), Tianjin University, Tianjin 300350, China.
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Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, CNRS, UMR 5223, Ingénierie des Matériaux Polymères, F-69621 Villeurbanne Cédex, France.
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View Article and Find Full Text PDFiScience
November 2024
Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
Largely varied anti-icing performance among superhydrophobic surfaces remains perplexing and challenging. Herein, the issue is elucidated by exploring the roles of surface chemistry and surface topography in anti-icing. Three superhydrophobic surfaces, i.
View Article and Find Full Text PDFInt J Pharm
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Institute of Energy and Process Engineering, ETH Zurich, 8092 Zurich, Switzerland. Electronic address:
Numerous commercially available biopharmaceuticals are frozen or freeze-dried in vials. The temperature at which ice nucleates and its distribution across vials in a batch is critical to the design of freezing and freeze-drying processes. Here we study experimentally how the level of particulate impurities - a key parameter in pharmaceutical manufacturing - affects the ice nucleation behavior.
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