Hi colleges. I was working in inhibition of pyoverdine expression in P. aeruginosa and performed swarming inhibition tests in semi-solid media too. I saw the results of swarming inhibition on the plate and exposed the plate under UV light for qualitative examination of pyoverdine expression. The results were a good inhibition of pyoverdine expression when were saw under UV light, but when I performed the inhibition of pyoverdine experiment in broth the results were more discrete, showing a poor inhibition of pyoverdine compared with the results in semi-solid media. Somebody have an idea why of these results? Thanks.