Feeding Techniques

Feeding experiments have been carried out either in situ or on organisms cultured in the laboratory. Many marine invertebrates, such as sponges, are filter feeders, digesting bacterial and other particular debris from the seawater.

Soft corals are carnivorous, feeding on microorganisms. Corals contain photosynthetic algae and, therefore, also take nutrients through this source. Thus, marine invertebrates may be herbivorous, carnivorous even omnivorous. In several biosynthetic experiments, precursors are fed in aqueous solutions, using either physiological saline or sterile seawater, except where the precursors are insufficiently soluble. Sterol precursors are fed in alcoholic solutions. The addition of Tween 80, perhaps, facilitates the transport of precursors across cell barriers. Labelled precursors can be injected into corals, sponges, star fish, molluscs or fish. Slow release techniques, such as liposomes or implants (e.g. gelatin capsule and osmotic pumps), embedded directly in cell tissues, are now being employed. Organisms can be maintained in an environment that contains the precursor or is provided with a labelled food source, such as microalgae grown on 14CO2. The nutrient levels in the oceans are normally of the micrograms per litre. The high concentrations of labelled precursors may overload the metabolic pathway. Besides, the concentration of precursor may prove toxic to organisms. The use of cell free extracts technique in marine biosynthetic studies is not very common, although it may resolve some of the problems such as uptake and transport of precursors, effects of symbiotic associations, etc. However, this technique is best suited where a reasonable rate of synthesis of metabolites is observed.

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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