Micro-algae

Agar occurs as a cell-wall constituent of the red marine algae Rho ophyceae, from which it is extracted by hot water, and marketed as a dry powder, flakes, or strips. It dissolves in hot water and sets on cooling to a jelly at a concentration as low as 0-5%. Its chief uses are as a solid medium for cultivating micro-organisms, as a thickener, emulsion stabilizer in the food industry and as a laxative. 

Other Microorganisms. There are several other microorganisms that affect the corrosion of metal directly or indirectly. Some examples are yeasts and molds, algae and protozoa. For the present purposes it is sufficient to realize that there are other micro-... 

Single cell protein, normally called simply SCP, is the term used to describe microbial cells, or proteins from them, which are used as food (food for humans) or feed (food for farm animals or fish). Although the term micro-organisms covers viruses, bacteria, fungi, algae and protozoa, viruses and protozoa are not considered suitable for SCP production. 

Micro-organisms are rich in protein. Microbial cells can contain as much protein as conventional foods. Bacteria can contain 60-65% (as a % of dry weight) protein whereas fungi and algae contain about 40%. In addition, microbial cells can be a rich source of fibre, unsaturated fats, minerals and vitamins. They are low in saturated fats and sodium. 

Item (1) is not always true. Some micro-organisms are easier to digest than plants, whereas others (such as algae) are more difficult to digest than many plant foods. 

Ecotoxicity assessment of water samples was carried out, in parallel to chemical analysis, using three standardized bioassays based on the micro-crustacean Daphnia magna, the algae Pseudokirchneriella subcapitata, and the bioluminescent bacteria Vibrio fischeri. 

Biofilms are a complex mixture of bacteria, algae and other organisms (Fig. 11). In well-illuminated environments, micro-algae (phytobenthos) make up the largest fraction of the biofilm biomass, which plays a vital role as a primary producer. However, in non-lit environments, heterotrophs (bacteria, protozoa) account for the greatest proportion within the biofilm. The composition and abundance of phytobenthos (periphyton or autotrophic biofilm) have a recognised role by the WFD. 

Fargasova, A. (1998). Accumulation and toxic effects of Cu2+, Cu+, Mn2+, VC>4, Ni2+ and M0O4- and their associations influence on respiratory rate and chlorophyll a content of the green alga Scenedesmus quadricauda, J. Trace Micro. Tech., 16, 481-490. 

Hydrogen metabolism investigations of micro-algae in daylight and darkness. 

Smith, V. J., Desbois, A. P., and Dyrynda, E. A. (2010). Conventional and unconventional antimicrobials from fish, marine invertebrates and micro-algae. Mar. Drugs 8,1213-1262. 

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