Gassed Biochemical Reactor constitutes an alternative to aerobic biochemical processes under enriched gas-atmosphere (air) at reactors of maximum volume of hundred liters, the works on labs and research purposes; the reactor is distinguished by pneumatic device to high-duty performances at processes environments of asepsis and isolation involving harmful products to the human health per substitution of higher costs mechanisms in analogous reactors; higher rates of oxygen-transfer at consistent theories and the repercussion at yields is foreseen; the safe and easy procedures at samplings and supplies and the breaking of unwanted foams distinguish the reactor performance; small compression units produce the sterile-air to the power supply and the oxygen to the cellular growing at reactors layouts in micro-plants; preliminary analysis of costs illustrates significant technical and economical profits; the calculus fundamentals are shown to a solved example for illustration. The book may concern to specialists of the pharmaceutical industry, engineers, students and professors at branches of bio-engineering.