Friday, October 25, 2013

Chemically Defined Medium as a Set Standard for Growth of Leuconostoc

Leuconostoc is a non-pathogenic, aero-tolerant anaerobic bacterial genus that lives on vegetation.
Leuconostoc plays an important role in industrial and food fermentations. Leuconostoc is often used for physiological and genetic studies related to polymer production.  Typically, a complex nutrient source comprised of beef and yeast extracts is used to support the growth of Leuconostoc, however, the exact chemical composition of the nutrient source remains uncertain and therefore may result in less desirable growth patterns than a defined nutrient source.  WIU undergraduate student, Megan McGlone has risen to the challenge for her undergraduate honors research project to determine if a defined nutrient source can serve as a suitable alternative to a complex nutrient source for growth of Leuconostoc.  To accomplish the research goal, Megan will cultivate Leuconostoc species for 12 hours in a defined nutrient source and a complex nutrient source. Bacterial growth in each nutrient source will be determined through two methods called viable plate count (quantitative) and spectrophotometry (qualitative). Growth rates (m h-1) and bacterial colonies formed per milliliter of culture broth (CFU/ml) will be calculated from the quantitative viable plate count. Spectrophotometry will be used as a real-time growth assessment to monitor the progress of each growth experiment. Data indicating that there is no statistical difference in growth between each nutrient source would support the use of defined as a suitable alternative to complex. In addition, data indicating an increase in growth for the defined would also support its use as an alternative to complex.  Megan's research advisor is Dr. Scott Holt.