Co-culture of myxobacteria and
The subject invention provides microbe-based products and efficient methods of producing them. In specific embodiments, methods are provided for enhanced production of microbial biosurfactants, the methods comprising co-cultivating Myxococcus xanthus and Bacillusamyloliquefaciens . In preferred embodiments, co-cultivation is carried out continuously for an indefinite period of time. Microbe-based products produced according to the subject methods are also provided, as well as their uses in, for example, agriculture, oil and gas recovery, and health care.
1. A method for enhanced production of one or more microbial growth by-products, the method comprising co-cultivating a first microorganism and a second microorganism in a fermentation reactor,
wherein the first microorganism is a myxobacterium and the second microorganism is B. amyloliquefaciens NRRL B-67928, and
wherein a greater concentration of the one or more microbial growth by-products is achieved than would be achieved if the first and second microorganisms were cultivated individually.
2. The method of claim 1 , wherein the myxobacterium is a Myxococcus spp.
3. The method of claim 2 , wherein the Myxococcus is M. xanthus.
4. The method of claim 1 , wherein the one or more growth by-products are biosurfactants.
5. The method of claim 4 , wherein the biosurfactants are lipopeptides.
6. The method of claim 5 , wherein the lipopeptides are surfactin, iturin and/or fengycin.
7. The method of claim 5 , wherein the biosurfactants are glycolipids and/or fatty acid esters.
8. The method of claim 1 , wherein a greater cell biomass is achieved for the first and/or second microorganism than if the first and second microorganisms were cultivated separately.
9. The method of claim 1 , wherein co-cultivating the first and the second microorganisms comprises:
inoculating the fermentation reactor with the first microorganism and inoculating the fermentation reactor with the second microorganism, wherein the fermentation reactor comprises a liquid nutrient medium;
incubating the first and second microorganisms under conditions favorable for growth and production of the one or more microbial growth by-products;
extracting the one or more growth by-products from the reactor;
collecting the one or more growth by-products in a collection container; and, optionally,
purifying the one or more growth by-products.
10. The method of claim 9 , wherein the liquid nutrient medium comprises a particulate anchoring carrier suspended therein as a site for nucleating microbial growth.
11. The method of claim 9 , carried out continuously for 1 week or longer, wherein the one or more growth by-products are extracted and collected on a consistent basis, and wherein the liquid nutrient medium is continuously replenished.
12. The method of claim 9 , wherein the one or more growth by-products are produced in the form of a foam layer.
13. The method of claim 1 , wherein the first microorganism stimulates enhanced production of the one or more growth by-products by the second microorganism.
14. The method of claim 1 , wherein the growth by-products are produced at a concentration that is at least 0.01% to at least 90% greater than if the first or the second microorganisms were cultivated separately.