Mixed cultures strains

Eortnagel P, H Harms, R-M Wittich, S Krohn, H Meter, V Sinnwell, H Wilkes, W Erancke (1990) Metabolism of dibenzofuran by Pseudomonas sp. strain HH 69 and the mixed culture HH27. Appl Environ Microbiol 5C. 1148-1156. 

Some studies have demonstrated the ability of mixed bacterial cultures to promote azo-dye conversion. The main advantage of mixed cultures is the ability to cope with conversion of both the dye and the main products of dye degradation. Characterization of individual strains in consortia has seldom been accomplished during continuous tests. Only a few attempts have been made to characterize the morphology of bacteria during continuous operation of bioreactors and to relate process efficiency to the bacterial population [32, 33]. 

Other preharvest techniques include the development of more resistant crops (e.g., Becker, 1999 Guo et al., 1998), and biological control with atoxigenic A. flavus strains (Cotty, 1990 Dorner et al., 1998). Atoxigenic A. jiavus competed successfully with a toxic isolate when they were grown in mixed culture, obtaining a reduction of the aflatoxin content by 82 to 100%. This is a worthwhile approach for control, however possible side effects caused by a preemptive application of A. jiavus in the environment must be studied to determine potential risks to human and animal health. 

Table 1 Fragments of Ecoflex after degradation with isolated pure strain (Tests 1-3) and with pure and mixed cultures from compost...

Vitamins and Minerals. Milk is a rich source of vitamins and other organic substances that stimulate microbial growth. Niacin, biotin, and pantothenic acid are required for growth by lactic streptococci (Reiter and Oram 1962). Thus the presence of an ample quantity of B-complex vitamins makes milk an excellent growth medium for these and other lactic acid bacteria. Milk is also a good source of orotic acid, a metabolic precursor of the pyrimidines required for nucleic acid synthesis. Fermentation can either increase or decrease the vitamin content of milk products (Deeth and Tamime 1981 Reddy et al. 1976). The folic acid and vitamin Bi2 content of cultured milk depends on the species and strain of culture used and the incubation conditions (Rao et al. 1984). When mixed cultures are used, excretion of B-complex vita-... 

Kemp, P., Lander, D.J. 1984. Hydrogenation in vitro of alpha-linolenic acid to stearic-acid by mixed cultures of pure strains of rumen bacteria. J. Gen. Microbiol. 130, 527-533. 

When both strains are growing at their maximum rate and contain about 4 X 10 cells/ml, they are mixed in the desired proportion. At the same time the strains are growing, the chemostats are filled with fresh medium and the flow of fresh medium started. The flow is adjusted and the chemostats equilibrated. For inoculation, 2 ml of freshly mixed culture is... 

Antibacterial activity has also been observed in P. pentosaceus and in one strain of L. plantarum that strongly inhibits the growth of O. oeni, L. mesenteroides and L. hilgardii. The discovery of these molecules gives only an indication of the true situation in wine. These could be species or strain-specific, so further studies are required to understand these relationships better. Fernandez and Manca de Nadra (2006) recently studied the interaction between a proteolitic strain of O. oeni and a non-proteolitic strain of P. pentosaceus and found a mutualism in the mixed culture, providing new knowledge about the metabolic interaction between LAB. 

Favale, S., Pietromarchi, R, Ciolfi, G. (2007) MetaboUc activity and interactions between two strains, Saccharomyces cerevisiae r.f. bayanus (SBC2) and Saccharomyces cerevisiae T.f.uvarum (S6u), in pure and mixed culture fermentations. Vitis, 46, 39-43. 

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