Triple Sugar Test in Microbiology Essay Example for Free

Triple Sugar Test in Microbiology EssayTriple sugar-iron (TSI) agar test- designed to differentiate among the different groups or genera of the Enterobacteriaceae, which are all gram-negative bacilli capable of fermenting glucose with the exertion of venereal infection a. Differentiation is made on the basis of differences in moolah fermentation patterns and hydrogen sulphide production. To facilitate observation of carbohydrate utilization patterns- TSI agar slants contain lactose and sucrose (1%) concentrations and glucose (0.1%) concentration which permits catching of the utilization of this substrate only. The acid base indicator phenol red- also incorporated to detect carbohydrate fermentation that is indicated by a change in color of the culture medium from orange-red to yellow in the aim of acids. a. Method to inoculate slant stab and streak procedure which requires insertion of sterile straight molest from the base of the slant into the butt. Upon withdrawal, the slanted surface of the medium is streaked. Determining activities of the organisma. Alkaline slant (red) and acid butt (yellow) with or without gas production (breaks in the agar butt) Only glucose fermentation has occurred. Glucose was degraded first. Since this substrate is minimally present, the small amount of acid produced on the slant surface is oxidized rapidly. Peptones in the medium are used in production of alkali. In the butt the acid reaction is maintained because of reduce O2 tension and slower growth of the organism.b.Acid slant (yellow) and acid butt (yellow) with or without gas production lactose and or sucrose fermentation has occurred. Since these substances are present in higher concentrations, they serve as the substrates for keep fermentative activities with maintenance of an acid reaction in both slant and butt.c.Alkaline slant (red) and alkalescent butt (red) or no change (orange-red) butt- No carbohydrate fermentation has occurred. Instead peptones are ca tabolized under anaerobic and or aerobic conditions resulting in an base-forming pH due to production of ammonia. If only aerobic degradation of peptones occur, the alkaline reaction is evidenced only on the slant surface. If there is aerobic and anaerobic utilization of peptone, the alkaline reaction is present on the slant and the butt.