Bacterial Strains and Growth Conditions for C. elegans Feeding

Escherichia coli OP50 was grown overnight at 37°C at 200 rpm in Luria-Bertani medium. The bacterial lawns used for the C. elegans studies were prepared by spreading 10 μl of the bacterial strain onto nematode growth media (NGM) agar (0.25% peptone) in 3.5-cm plates. The plates were incubated overnight in an incubator at 37°C. They were allowed to equilibrate to room temperature before they were seeded with C. elegans and incubated at 20°C throughout the experiment.

All the bifidobacterial strains cited in the Table ​Table11 (except E. coli) were grown as shown above. Bacterial lawns were made by spreading 10 μl of the bifidobacterial strains onto MRS agar in 3.5-cm plates. A similar procedure to that described above was followed, but C. elegans was fed different Bifidobacterial (B. longum and B. adolescentis) strains rather than E. coli OP50. B. longum and B. adolescentis were considered further for these studies as it is preferred by the C. elegans. The second generation of this bacteria is microaerophilic therefore they can grow in aerobic condition, where C. elegans also grows.