Methods of culturing microorganisms in combinations of phototrophic, mixotrophic, and heterotrophic culture conditions are disclosed. A culture of microorganisms may be transitioned between culture conditions over the life of a culture in various combinations, utilizing various conditions in a sequential manner to optimize the culture for growth or product accumulation.

The invention relates to an aqueous composition for the suppression of dust, comprising 1) an anionic surfactant; 2) an amphoteric surfactant; 3) a Bacillus species; and 4) a carbohydrate-based feedstock on which the Bacillus can grow. The composition is capable of forming a foam. When mixed with dust, the composition, in particular the foam thereof, is effective in preventing the dust from becoming airborne. Further, when applied before grinding or milling a material, the spreading of dust during and after the grinding or milling is effectively prevented.

The invention relates to an aqueous composition for the suppression of dust, comprising 1) an anionic surfactant; 2) an amphoteric surfactant; 3) a Bacillus species; and 4) a carbohydrate-based feedstock on which the Bacillus can grow. The composition is capable of forming a foam. When mixed with dust, the composition, in particular the foam thereof, is effective in preventing the dust from becoming airborne. Further, when applied before grinding or milling a material, the spreading of dust during and after the grinding or milling is effectively prevented.

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.

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.

The invention provides an assay for identifying a bacterium capable of binding elemental heavy metal, comprising the following steps: cultivating a test bacterium in a suitable first culture medium; immersing at least a surface portion of a test tool into the first culture medium for a second predetermined period of time, said surface portion being coated by elemental heavy metal, respectively; removing said test tool from said first culture medium and optionally rinsing the test tool; contacting a second culture medium with the surface portion coated by elemental heavy metal of said test tool removed in the previous step; and identifying the test bacterium as being capable of binding elemental heavy metal from growth of the test bacterium in said second culture medium.

The invention provides an assay for identifying a bacterium capable of binding elemental heavy metal, comprising the following steps: cultivating a test bacterium in a suitable first culture medium; immersing at least a surface portion of a test tool into the first culture medium for a second predetermined period of time, said surface portion being coated by elemental heavy metal, respectively; removing said test tool from said first culture medium and optionally rinsing the test tool; contacting a second culture medium with the surface portion coated by elemental heavy metal of said test tool removed in the previous step; and identifying the test bacterium as being capable of binding elemental heavy metal from growth of the test bacterium in said second culture medium.

Microfluidic gradient generators that can create robust platforms that can not only be used for creating co-cultures of cells with various ratios, but also can simultaneously generate gradients of mechanical and chemical stresses. A chip utilizes microchambers embedded within channels to provide space for 3D cell culture and exposes these cells to gradients of mechanical shear stress and a chemical treatment.

Microfluidic gradient generators that can create robust platforms that can not only be used for creating co-cultures of cells with various ratios, but also can simultaneously generate gradients of mechanical and chemical stresses. A chip utilizes microchambers embedded within channels to provide space for 3D cell culture and exposes these cells to gradients of mechanical shear stress and a chemical treatment.

The invention provides a process of isolating or enriching a heavy metal present in a liquid medium. The process comprising the following steps: (a) incubating a suspension containing (i) particulate scrap metal, household waste and/or industrial waste containing a heavy metal in elemental form and (ii) biomass comprising a bacterium, or a combination of two or more bacteria, capable of binding the heavy metal; (b) separating the biomass having bound heavy metal from the suspension of step (a); and (c) isolating the heavy metal from the biomass separated in step (b).