A method for the manufacture of products by biotechnological methods in bacterial cell culture is disclosed as well as products obtained, the use of certain additives to the media used in the manufacture of said products in bacterial cell culture media, and the use of said additives in reducing the detrimental effects of radicals in the manufacture of the products, as well as aspects related to these invention embodiments. The manufacturing process or method comprises adding one or more radical scavenging and/or antioxidative additive preferably selected from the group consisting of sterically hindered nitroxyls, sterically hindered hydroxylamines, sterically hindered hydroxylamine salt compounds, sterically hindered amino compounds and sterically hindered N-hydrocarbyloxyamines, benzofuranone compounds, as obligatory component(s) to the medium used during biosynthesis.