Calcium-free Seawater
Calcium-free Seawater - Related Videos
08:23
Seawater Sampling and Collection
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Cited by 13 •
2009
This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass concentration, nucleic acid purification, cell abundance, nutrient and trace gas analyses.
05:58
Large Volume (20L+) Filtration of Coastal Seawater Samples
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Cited by 16 •
2009
This video documents large volume (≥20 L) filtration of microbial biomass, ranging between 0.22μm and 2.7μm in diameter, from the water column.
04:21
Small Volume (1-3L) Filtration of Coastal Seawater Samples
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Cited by 7 •
2009
This video documents small volume (~1 L) filtration of microbial biomass from the water column.
03:07
Selective Enrichment and Isolation of Oil-Degrading Marine Bacteria from Seawater Samples
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2025
Source: Villela, H. D. M., et al. Prospecting Microbial Strains for Bioremediation and Probiotics Development for Metaorganism Research and Preservation. J. Vis. Exp. (2019)This video demonstrates the selective isolation of oil-degrading marine bacteria by enriching seawater samples on oil-based media, enabling the recovery of pure strains with potential applications in crude oil bioremediation and environmental cleanup.
08:43
Aerobic Biodegradation Testing of Materials Using a Natural Marine Seawater Inoculum and Closed Loop Respirometer
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2025
The protocol describes standard operating procedure for testing potentially biodegradable materials both synthetic and natural under aerobic conditions using a natural seawater inoculum and automated closed loop respirometry system.
FAQs
It reduces calcium entry, calcium binding, and calcium-dependent signaling outside the cell. A response that weakens in the calcium-free condition can therefore be associated with extracellular calcium dependence, while a response that persists suggests involvement of other ions or calcium-independent mechanisms. This comparison helps separate calcium-specific effects from broader effects of the seawater environment.
Maintaining salinity and pH limits unwanted changes in the experimental environment. If these conditions remain comparable to normal seawater, differences in cell or tissue behavior can be interpreted more specifically in relation to calcium availability. This controlled comparison is especially important when examining membrane permeability, ion regulation, or signaling in marine organisms.
Processes that depend on coordinated cellular signaling or mechanical activity can show pronounced changes when extracellular calcium is reduced. Muscle contraction, fertilization, neurotransmitter release, and membrane-related responses provide distinct readouts of calcium involvement. Examining several processes allows researchers to determine whether calcium affects communication, force generation, reproductive events, or ion movement in a particular system.
The experiment uses seawater in which dissolved calcium ions are either removed or omitted, while relevant seawater conditions such as salinity and pH are maintained. Biological samples are then evaluated under the calcium-free condition and compared with samples in normal seawater. The resulting contrast provides a basis for identifying responses associated with extracellular calcium.
Researchers choose it when they need to test whether a marine biological response requires extracellular calcium. The approach is useful for isolating calcium-dependent components of membrane behavior, contraction, fertilization, neurotransmitter release, or ion regulation. Normal seawater supplies the comparison condition, allowing the experimental outcome to be interpreted as a change linked to calcium availability.
Such comparisons can show how calcium contributes to cellular communication, mechanical activity, and physiological adaptation. In marine organisms, the findings may indicate whether a tissue or cell relies on extracellular calcium for a specific response or can maintain that response when calcium-dependent pathways are reduced. This supports broader studies of marine physiology and experimental cell biology.