Abstract: A mixing device, especially for a fermenter, capable of dispersing gas in a broth therein, in which a number of propeller mixers are provided on a vertically extending shaft. The lower propeller mixer is a gas dispersing mixer having a hollow hub and open channels on the blades extending from this hub and tapering outwardly. At least one intermediate propeller mixer has some blades shorter than others and of reverse flow direction, some blades having baffle bars on trail edges thereof. The upper propeller mixer has the longer blades without channels and flow modifying elements.

Abstract: Complex mixing system with stages consisting of propeller mixers of high diameter ratio, where the blades are provided with flow modifying elements, whereby the energy proportions spent on dispersion of the amount of gas injected into the reactor, homogenization of the multi-phase mixtures, suspension of solid particles, etc. and the properties corresponding to the rheological properties of the gas-liquid mixtures and to the special requirements of the processes can be ensured even in extreme cases. Open channels (5) opposite to the direction of rotation are on the blades (4) of the dispersing stage (2a) of the propeller mixers (2) fixed to a common shaft, where the channels (5) are interconnected with gas inlet (7). The angle of incidence of a certain part of the blades (4) of mixing stages (2b, 2d) used for homogenization and suspension is of opposite direction and the length is shorter and/or the angle of incidence is smaller than those of the other blades.

Abstract: The invention relates to a microbial process for the production of immunosuppressive cyclosporine antibiotic complex or of its components, cyclosporine A, cyclosporine B and cyclosporine C, by the aerobic fermentation of a filamentous fungus strain biosynthesizing the above antibiotic(s) in a nutrient medium containing utilizable carbon and nitrogen sources as well as mineral salts, and by isolating the products formed, which comprises culturing a strain of the novel Tolypocladium varium fungus species producing the cyclosporine antibiotic complex, preferably tolypocladium varium sp. nov. CY/93, deposited at the National Collection of Agricultural and Industrial Microorganisms, Budapest, Hungary under the number NCAIM(P)F 001005, on a nutrient medium containing carbon sources, organic and inorganic nitrogen sources as well as mineral salts, under aerobic conditions, at 25.degree. to 30.degree. C., and, if desired, isolating and purifying the cyclosporine antibiotic complex or its components produced.