» Prospective Students » Current Students » Faculty & Staff » Alumni & Visitors » About Us » Diversity » Policies » Calendar
Engineering

Example Abstract for Engineering

1st Position, Eighteenth Annual Graduate Exhibition

KATHIRAVAN KRISHNAMURTHY

College: Agricultural Sciences
Department: Agricultural and Biological Engineering
Title: Pulsed UV-Light Sterilization for inactivation of Staphylococcus aureus
Abstract:

The Centers for Disease Control and Prevention (CDC) estimate that there are 76 million illnesses, 325,000 hospitalizations, and 5,000 deaths per year in the United States alone as the result of consumption of food contaminated with pathogenic microorganisms. Staphylococcus aureus is one of the common food-borne pathogen responsible for major outbreaks. Staphylococcus aureus is capable of producing several toxins which cause food-borne illnesses. Pulsed UV-light sterilization is a emerging technology, which can be used to inactivate microorganisms effectively by destroying their ability to grow. Pulsed UV-light sterilization is a cost effective alternate for several other preservation techniques available. This method can be very effective in reducing the microbial population in a short time without affecting the quality considerably. In this study, we evaluated the efficacy of pulsed UV-light treatment on cell suspension and agar seeded S. aureus. A 12, 24, or 48 ml of cell suspension of S. aureus in buffer was treated with pulsed UV-light for 1, 2, 3, 4, 5, 10, 15, or 30 seconds. A 0.1 ml of treated and untreated samples was surface plated on Baird-Parker agar and incubated at 37'C for 24 h. The colonies were enumerated and the log reduction was estimated. Also, a 0.1 ml of cell suspension of S. aureus in peptone water was surface plated on Baird-Parker agar plates and the plates are treated under pulsed UV-light for 1, 2, 3, 4, 5, 10, 15, or 30 seconds. The treated and untreated plates are incubated at 37'C for 24 h and colonies were enumerated. After 5 second treatment, no growths were observed in both direct plate treatment and phosphate buffer treatment. The corresponding reduction obtained after 5 second was 7 to 8 log CFU/ml in both cases.