CYANOBACTERIA

Cyanobacteria

Cyanobacteria.

Introduction

Algae are very simple chlorophyll-containing organisms. In general, simple organisms composed of one cell, or grouped together in colonies, or as organisms with many cells, sometimes collaborating together as simple tissues. Phytoplankton is a form of algae and it is known to provide food for fish, this phytoplankton grows in vast numbers in both fresh and marine waters. Algae are extremely important for releasing oxygen formed during the process of photosynthesis.

In areas where there are a lot of brown algae, the plants are ground and used to fertilize the soil. Some algae are used in special foods and it is also produced commercially to provide a source of protein for both humans and domestic animals. The largest forms of algae are seaweeds that can be 100 m from the ocean bottom to the water's surface.

Although most algae grow in fresh water or seawater, they also grow on soil, trees, and animals, and even under or inside porous rocks, such as sandstone and limestone. Algae tolerate a wide range of temperatures and weather conditions such as; in hot springs, on snow banks, or deep inside polar ice. (Sutton 1998 12 )

Discussion

These cyanotoxins include cyclic peptides and alkaloids. Among the cyclic peptides are the microcystins and the nodularins. The alkaloids include anatoxin-a, anatoxin-a(S), cylindrospermopsin, saxitoxins (STXs), aplysiatoxins and lyngbyatoxin. Both biological and chemical methods are used to determine cyanotoxins. Bioassays and biochemical assays are nonspecific, so they can only be used as screening methods.

HPLC has some good prospects. For the subsequent detection of these toxins different detectors may be used, ranging from simple UV-spectrometry via fluorescence detection to various types of MS. The main problem in the determination of cyanobacterial toxins is the lack of reference materials of all relevant toxins. (South & Whittick 1987 14)

Water that is polluted with organic matter or sewage provides an ideal environment for the growth of many algae and as a result of this blooms are formed, these blooms are a good indication of water pollution.

These blooms can occur when the algae die and decompose, depleting the dissolved oxygen in the water. There are many different types of algae and one type of algae is blue-green algae, cyanobacteria,Cyanobacteria are a much simpler type of cell, compared with the eukaryotic cells which are typical to the majority of species, as it lacks organelles. This type of cell is considered to be a prokaryotic cell. Prokaryote means 'before the nucleus' stating that the DNA is not enclosed by a membrane. Prokaryotes contain characteristics different to a eukaryotic cell which help aid the function of the cell, these featured characteristics are; plasmids, flagellum, capsule, genetic material, thylakoids, nucleoid and mesosomes. However unlike most algae cyanobacteria do not contain a flagellum for movement, it can move by gliding over surfaces or creating gas vesicles. (Roberts 1986 16)

Cyanobacteria are part of the oxygen-producing bacteria group and formed rocklike structures called stromatolites. Due to Cyanobacteria being able to perform oxygenic photosynthesis, it is thought to have changed the early ...