Dynamics of Bacterial Communities in Postharvested Eastern Oyster (Crassostrea virginica) Maintained Under Refrigeration

Abstract

The selective effect that refrigeration exerts on the autochthonous microbiota of the eastern oyster was investigated using culture-independent methods. Oysters from two different locations along the Gulf Coast of Mexico were analyzed concurrently during 2-week refrigeration. Ribosomal intergenic sequence analysis (RISA) generated complex bacterial community fingerprints that provided a strong association between RISA-defined clusters and sample date. Denaturing gradient gel electrophoresis (DGGE) profiles obtained with universal primers did not reflect any association based on date or geographic origin of the samples. During the storage period, Vibrio parahaemolyticus was replaced, at least in overall abundance, with other nonpathogenic Vibrio species better adapted to cold temperatures. This study shows that refrigeration itself does not limit the growth of the bacterial community nor reduces its richness.

Keywords:

• eastern oyster
• Vibrio
• Vibrio parahaemolyticus
• bacterial community
• refrigeration