Abstract: The invention relates to the use of microjet reactor for processing biomass. The cell lysis of flowable biomass is thereby carried out by means of multiple high-speed liquid jets which collide with one another, wherein the liquid jets contain the cells or consist wholly of the flowable cell mass, wherein intact or wholly or partially lysed biomass is added to at least one of the colliding high-speed liquid jets, and an extraction takes place simultaneously with the collision of the liquid jets or subsequently thereto. The lysis of the cells is initiated or facilitated by the forces that occur on acceleration, introduction of the acceleration, collision of the jets and mixing of the jet constituents.