Affiliation:
1. Department of Food Science, University of Georgia Agricultural Experiment Station, Experiment, Georgia 30212
Abstract
Propionibacterium shermanii
and
Lactobacillus acidophilus
were grown in batch mixed culture in a 5-liter fermenter under controlled conditions of pH 5.8 and 35°C on a semisynthetic medium with glucose as an energy source. Cellular efficiencies and fermentation balances were developed for this pair and compared with
P. shermanii
grown in pure culture on glucose, lactate, and a mixture of these substrates and with
L. acidophilus
grown on glucose.
P. shermanii
had ATP yield coefficient values of 17 for each substrate alone but had an average value of 30 for substrate mixtures. Growth rates were similar for
P. shermanii
on glucose or lactate but higher cell yields were observed for glucose.
P. shermanii
used both lactate and glucose in mixed substrate until lactate was exhausted, and growth rates slowed thereafter.
L. acidophilus
had a similar ATP yield coefficient of 15 but produced lower cell yields than did
P. shermanii
on glucose. Mixed culture of both microorganisms on glucose resulted in much faster and nearly equal growth rates for both and no lactate accumulation in the medium. Acetic acid production rates per generation were lower in mixed culture, suggesting use by the growing culture. The cause of the synergistic effect was not determined but may be due to the rapid production and removal of lactate or CO
2
enhancement in mixed culture.
Publisher
American Society for Microbiology
Subject
Ecology,Applied Microbiology and Biotechnology,Food Science,Biotechnology
Reference15 articles.
1. Generation of ATP during cytochromelinked anaerobic electron transport in propionic acid bacteria;de Vries W.;J. Gen. Microbiol.,1973
2. End-products. fermentation balances and molar growth yields of homofermentative lactobacilli;Dirar H.;J. Gen. Microbiol.,1972
3. Growth and acid production by Lactobacillus (L.) delbrueckii in a dialysis culture system;Friedman M. R.;Biotechnol. Bioeng.,1970
4. Hausler W. J. 1972. Standard methods for the examination of dairy products 13th ed. American Public Health Association Washington D.C.
5. The propionic acid bacteria-a review;Hettinga D. H.;II. Metabolism. J. Milk Food Technol.,1972
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