Micro Lan Unknown Bacteria Salmonella Essays

Micro Lan Unknown Bacteria Salmonella Essays Micro Lan Unknown Bacteria Salmonella Essay Micro Lan Unknown Bacteria Salmonella Essay Title: â€Å"Identification of Unknown #1† Purpose:Discovering and studying new bacteria can lead to new innovations and possible cures for existing or future diseases. The investigation of bacteria can also help incubate ourselves or act quickly in response to an invasive strain. The commercial food industry has a great need in identifying Salmonella to prevent disease in consumers. As well as being the cause of enteric (typhoid) fever, an important infectious disease, Salmonella is perhaps best known as a cause of bacterial food poisoning. Although typhoid fever has been largely eradicated in the developed world, Salmonella food poisoning has long been, and continues to be, an important global public health problem. In much of Europe and North America, Campylobacter is now the most frequent cause of foodborne human infections, but Salmonella remains a very important and widespread pathogen. It is a major cause of concern for the food industry, where its control is vital for products ranging from cooked meats to chocolate and from fresh produce to peanut butter. Given the long history of foodborne salmonellosis, it is not surprising that the need for microbiological testing of food ingredients and food products is very significant. A substantial number of methods, both traditional and rapid, have been developed over the years for the detection and identification of Salmonella. Salmonella, a small, gram-negative bacillus, are relatively resistant to stomach acids. Feces of patients that have symptoms of food poisoning or typhoid fever are cultured for Salmonella. Often, the preliminary diagnosis is first suggested by recognition of an outbreak (multiple patients having symptoms of a disease all at about the same time and often from the same food or water source). Again, many organisms and toxins can cause food poisoning, so it is sometimes difficult to determine the outbreaks cause. Usually, the laboratory needs to be notified that S. spp. is suspected as the cause so they will choose the correct testing media (selective agar media such as SS agar plates) to distinguish Salmonella from other potential bacterial pathogens such as E. oli, Shigella strains, Staphylococcus food poisoning, or from toxins like botulism or pesticides. The majority of Salmonella isolates come from the feces of the infected person. Occasionally, Salmonella can be cultured from blood samples. Serovars are identified by serotyping (detecting bacterial proteins by using specific immunological tests). Definitive diagnosis usually requires that the bacteria be isolated and identified by these techniques. PCR tests also have been used to distinguish between bacterial strains. Treatment for food poisoning is controversial. Some doctors recommend no antibiotics since the disease is self-limited, while others suggest using antibiotics such as ciprofloxacin for 10-14 days. Some medical investigators believe antibiotics prolong the carrier state. However, patients identified as immunosuppressed should receive antibiotics; they may need to be hospitalized and have some of their care managed by an infectious disease consultant. Supportive therapy for both enteritis and enteric fevers consists mainly of preventing dehydration and electrolyte abnormalities (for example, abnormal levels of potassium and sodium ions) with fluids containing electrolytes (for example, IV fluids or oral fluids like sports drinks). Materials and Methods:See attached Results and Observations: See attached Conclusion:I am fairly confident that my unknown, number 1, is Salmonella typhimureum. All results from the vast experiments performed, with the exception of the Voges-Prosekauer during the MR-VP test, which may have been read incorrectly when I thought that the indicating result was red/brown in color, pointed me in the direction of the detection of this particular bacterium out of the fifteen possible organisms. I knew that the Methyl Red portion of the MR-VP confirmed that the pH was less than or equal to 4 making this quite an alkaline agent, and reconfirmed alkalinity with the final experiment with the use of the litmus milk broth turning blue. The Gram negative stain and rod shape eliminated six of the possibilities. The SIM (Sulfur Motility and Indole) testing proved that the organism was motile, was a gas producer, did not produce indole, and Triple Sugar Iron-Agar Slant produced a black butt and red slant indicating glucose fermentation and confirmed sulfur gas production, leaving only Proteus vulgaris as another possible outcome. Casein, gelatin, and urease testing were needed to conclude my results, as only P. vulgaris would be found to ossess the enzymes casease, gelatinase, and urease, which, none of those were found in my unknown organism. Both of the two organisms were negative to hydrolyze starch, and neither can metabolize oxygen. Most infections with Salmonella are traced back to dairy, poultry and meat products, but Salmonella can grow on just about any food. Chickens and eggs are particular high risk foods. Proper storage with the use of cool temperatures in a refrigerator, proper handling including cooking t emperatures that are hot enough to kill the bacteria are vital to prevent the disease.