Trend in Microbiology – 2011
Microbiology, inconceivably, goes molecular. The development of scientific knowledge in food microbiology has long touched the molecular level. Analysis and mapping of functional DNA from microorganisms that are pathogenic or useful to the modern society have been widely available. Technology of identification and recombination of DNA, e.g. PCR, has also been developed and accepted as a standard. To date, to confirm a doubtful species or a sub-strain requires DNA analysis.
These conditions are present. So, in what direction the development of microbiology will be next?
The use of recombinant DNA allows certain DNA sequences, or markers, embedded in observed species. Plasmids with protein translational codes of green fluorescent (GFP), yellow (YFP) and red (RFP), accelerate the development of microbiology to understand more complicated physiological processes, such as successive fermentation. Additional benefit of employing this fluorescent protein is inexpensive requirement of observational tools, i.e. Fluorescence Activated Cell Sorting which also can provide live observation.
Implementation of the fluorescent protein in food related world can be exemplified in the four stages of cocoa fermentation: initial growth of proteolytic bacteria/mold, alcohol-producing yeast, acetic acid bacteria, and another growth cycle of proteolytic microorganisms. In detail, analyzes of microbial growth in each cycle have been reported with conventional isolation techniques. But a finding leads to thousand questions, i.e. to what extent compound produced by each group of microbes play a role in cocoa bean flavor? In conjunction with the use of transfection fluorescent protein as a marker for protein production in cells, the optimum production of proteolytic compounds from fungi/bacteria involved in fermentation of cocoa can be observed.
Fermentation with mixed culture techniques also benefit by the existence of this fluorescent protein technology. As for example, obtaining the growth curve of each Lactobacilli species in course of milk fermentation is not an impossible task. Further, the result can improve standardization of fermented milk.
Another anticipated trend in microbiology in coming years is the analysis of microorganism and cell secretions associated with symptoms of certain diseases. Increased production of pro-inflammatory cytokine, tumor necrosis factor alpha (TNF-α), and nitric oxide (NO) is established as an early symptom of inflammation in living organisms. Therefore, the production of these compounds are sought to be down regulated. Baker yeast can act as a model microorganism that produces TNF-α in the initial selection of antioxidants and functional components of prospective food. This new study, in general, is an intersection of molecular microbiology, pharmacology, and functional foods.
To sum up, the science of microbiology will put more efforts in molecular levels. It is expected that greater knowledge will be obtained with respect to optimization of fermentation quality, health improvement, and the discovery of new drugs. The current technology in PCR-based isolation and identification of strain level microorganisms has been established as the approved standard.