Abstract: The present invention relates to a new microbial process for the preparation of compound of formula (I) from a compound of general formula (II) wherein R stands for an alkali metal or ammonium ion, by the submerged culture of a strain which is able to 6?-hydroxylate the compound of formula (II) in aerobic fermentation and by the separation and purification of the product of formula (I) formed in the course of the bioconversion. The latter comprises the cultivation of a Micromonospora strain which is able to 6?-hydroxylate a compound of general formula (II)—wherein R is as defined above—at 25-32° C. on a nutrient medium containing available carbon—and nitrogen sources and mineral salts, thereafter feeding the substrate to be transformed into the developing culture, then hydroxilating the substrate until finishing of the bioconversion, then separating the compound of formula (I) from the culture broth and, if desired, purifying the same.

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.