Effect of aeration on the novobiocin fermentation.

A direct relationship has been shown between the maximum cell concentration and aeration efficiency with aerobic microorganisms (Maxon and Johnson, 1953; Smith and Johnson, 1954). Since the antibiotic titer generally varies directly with the weight of mycelium in streptomycete fermentations, it is imperative to define the dependence of antibiotic and mycelial syntheses on the aeration efficiency in the particular fermentation under study. Relationships amonig novobiocin synthesis, mycelial production, and aeration lev,el in shake flask fermentations have been investigated and the results are presented in this publicationi. In a previous report (Smith, 1956), it was showvn that aeration was probably not a limiting factor in the novrobiocin fermentation under certain shake flask conditions. It has since been observed that the addition of various nitrogenous materials to a distillers' solubles medium depresses novobiocin synthesis. This depression appears to be due in part to an induced oxygen deficiency, as described in this publication. A simplified ultraviolet (UV) assay procedure for novobiocin is also presented.