A bioreactor arrangement has a bioreactor and an illuminating body for illuminating a medium in a reactor interior. The illuminating body has at least one emission surface via which light, reflected by at least one end surface into the reactor interior, is emitted. The bioreactor is formed as a container having a transparent wall. The illuminating body is outside the reactor interior, next to at least one subregion of the transparent wall. The illuminating body forms a support surface for the bioreactor with its emission surface. A shaking device has a reactor holder that can be in oscillated, for a bioreactor with a transparent wall. The reactor holder has a two-dimensional illuminating body, the emission surface of which forms a support surface for the bioreactor, via which light can be reflected into the reactor interior of the bioreactor.