Automated method for selecting microbial strains which can degrade or emulsify oil

An automated method for selecting a microbial strain from within a microbial strain library which can degrade or emulsify a target oil substrate, said method comprising in no particular order, unless specified:

• (a) providing a plurality of receptacles adapted to receive a liquid microbial cell culture as part of a multi-well culture plate wherein the internal surface(s) of the receptacles are coated, at least in part, with a layer of the target oil substrate;
• (b) applying to each of said oil-coated receptacle a sample of one of the members of the strain library, wherein a plurality of members of the strain library are applied to the plate;
• (c) culturing said samples in a liquid cell culture medium and monitoring said oil layer coating at least part of the internal surface(s) of said receptacles for a change in its appearance, wherein a change in the appearance of said oil layer coating at least part of the internal surface(s) of said receptacles is indicative of degradation or emulsification of said target oil substrate;
• (d) selecting those samples from step (c) which caused degradation or emulsification of the oil substrate;
• (e) separately culturing either (i) all the members of the library applied in step (b) or (ii) the library members selected in step (d) in the presence of an n-alkane and monitoring for degradation of said n-alkane;
• (f) separately culturing either (i) all the members of the library applied in step (b) or (ii) the library members selected in step (d) in the presence of a polycyclic aromatic hydrocarbon (PAH) and monitoring for degradation of said PAH;
• (g) subjecting either (i) all the members of the library applied in step (b) or (ii) the library members selected in step (d) to environmental tolerance testing, wherein said testing comprises culturing the library members under varying environmental conditions and determining the limits of these conditions at which colony viability ceases, wherein said environmental conditions tested comprising temperature, pH and ionic concentration, and optionally further comprising O2 concentration or pressure;
• (h) optionally repeating steps (a) to (c) with the library members selected at step (d);
• and
• (i) selecting a microbial strain on the basis of its performance in steps (c), (e), (f), (g) and optionally (h).