ARS | Publication request: Antimicrobial profiles of substrates monitored by volatile emissions of individual species and mixed consortia of bacteria

Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: October 9, 2008
Publication Date: October 21, 2008
Citation: Arnold, J.W., Edwards, J.V. 2008. Antimicrobial profiles of substrates monitored by volatile emissions of individual species and mixed consortia of bacteria. Industrial Fabrics Association International Conference.

Technical Abstract: Earlier we introduced diverse profiles of volatile compounds emitted from single bacteria and from mixed populations that demonstrated changes that occurred in response to changes in bacterial communities. Physiological responses of bacteria mediate the balance among the microorganisms within a consortium that determines the survival and growth of the resident bacteria. We have studied substrate utilization profiles and volatile emissions of individual bacterial species and mixed microbial communities (biofilm). The rapidity and frequency of utilization of individual and groups (i.e., polymers, carbohydrates, etc.) of substrates varied by changes in the microflora and changes in temperature. Differences occurred among the volatile compounds produced by the microbial consortia associated with samples stored at various temperatures. Substrates were monitored by enumeration of microbial load. Surface odors are noted when the bacterial counts reach about log10 6-7 cfu g-1; and, at storage temperatures of 10'C or lower, are caused primarily by species of Pseudomonas and Acinetobacter. Metabolism of groups of chemically related substrates followed the order polymers> carbohydrates> carboxylic acids>miscellaneous or amino acids>amides/amines at 13'C. Utilization of these substrate groups was not as variable at 4'C as the profile of volatile emissions. Although the frequency of metabolism of each individual substrate group varied only 3-16% between samples stored at 4 and 13'C, a difference of more than 30% in frequency of utilization of 17 individual substrates was noted. Such divergences may be useful in characterizing bacteria communities that affect quality of products. Understanding the metabolic processes of microorganisms from production and processing environments leads toward the ultimate goal of controlling these processes to prevent biofouling.