A Method for Injecting Insect Tracheae Permanently

By the use of an alcohol insoluble dye (trypan blue), acetic acid, and a detergent (“Santomerse No. 3”), a resulting dye solution is obtained which will completely penetrate the tracheal system of an insect. The dye is injected by the use of a vacuum and by the pressure produced when the air is allowed to re-enter the dye vessel. The dye itself is permanently fixed in the tracheae by means of a fixing solution containing alcohol, acetic acid and barium chloride as its components. The material must be properly preserved after staining. It may be stored indefinitely in 70% alcohol, xylol, cedar oil or clove oil, depending on whether the material is to be used for sectioning or for whole mounts. Injected material may be sectioned in either celloidin or paraffin, or may be cleared and mounted in toto.     

Analysis of microbial exopolysaccharides from industrial water systems

Summary The monosaccharide composition of exopolysaccharides extracted from mixed microbial slimes from cooling towers and process waters of paper machines was determined. Gas chromatographic evidence demonstrated that the microbial slimes found in these industrial systems were heteropolysaccharides, each composed of more than one monosaccharide. Monosaccharides identified in deposit samples were glucose, mannose, galactose, rhamnose, fucose, and glucuronic acid. The methods reported allow efficient extraction and analysis of microbial exopolysaccharides, and the results have implications for slime control strategies in industrial systems.