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A novel antibiotic complex has been isolated from the fermentation broth of a new species of Actinomadura, A. kijaniata SCC 1256. The complex was separated from the broth by a solvent extraction procedure and consists of 1 major component, designated kijanimicin, and 3 minor components.Kijanimicin was isolated from the complex by column chromatography and/or preparative high pressure liquid chromatography.Structurally the compound is a unique, large acid enol antibiotic and possesses an unusual in vitro spectrum of activity against some Gram-positive and anaerobic microorganisms.In vivo it has also shown interesting activity against malaria.In the course of our screening for novel antibiotic producing organisms, a culture was noted that appeared distinct in pigmentation from cultures previously observed. This strain, designated SCC 1256, was found to be producing a complex of novel antibiotics from which the major component, designated kijanimicin (Sch 25663) was separated. These antibiotics were active against an unusual spectrum of microorganisms including anaerobes, particulary Propionibacterium acnes. In vivo activity against Plasmodium berghei and P. chabaudi in mice was also observed. This paper details the fermentation and isolation of the antibiotic complex, as well as purification, identification, characterization, 14C labelling, and biological activity of the major component, kijanimicin. Details of the taxonomic evaluation of the producing organism as well as chemical structure elucidation appear elsewhere1-3) . Producing CultureThe producing culture was isolated from a soil sample collected in Kenya. The culture has been identified as a new species of the genus Actinomadura, designated A, kijaniata'~. The strain has been deposited in the American Type Culture Collection, Rockville, Maryland, U.S.A. and has been assigned accession number ATCC 31588. Production of KijanimicinThe medium used for the preparation of the inoculum for antibiotic production consisted of 0.3 beef extract, 0.5% tryptose, 0.1% dextrose, 2.4% potato starch and 0.2% calcium carbonate. The pH of this medium was adjusted to 7.2 prior to sterilization. A 300 ml Erlenmeyer flask containing 70 ml of this medium was inoculated with 5 ml of the stock suspension of the producing strain maintained at -20°C.The flask was incubated at 30°C on a rotary shaker at 250 rpm for 48 hours.

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A new antibiotic, rosamicin, classified as a macrolide, has been isolated from the fermentation broth of a new species of Micromonospora, M. rosaria.The antibiotic is separated from the broth by a solvent extraction procedure and purified by column chromatography. Chromatographic studies indicate that rosamicin is different from all related macrolides and is a novel antibiotic. It has broad-spectrum activity, although it is more potent against gram-positive organisms. Rosamicinis also active against Mycoplasma.The first macrolide antibiotic to be isolated from a species of Micromonospora was megalomicin, produced by M. megalomicea.1} A new macrolide antibiotic unrelated to megalomicin and named rosamicin has now been isolated from the fermentation broth of another new species of the genus Micromonospora. This paper presents initial data on the taxonomyof this neworganism, and primary data concerning the chemical and biological properties of rosamicin. Materials and MethodsThe organism which produces rosamicin is a newspecies of Micromonospora, named M. rosaria and assigned NRRLNo. 3718. This culture was isolated from a. soil sample:obtained from Little Thicket, San Jacinto County, Texas.The colonial morphology of a 14-day old culture was determined after incubation at 24~26°C on an agar medium consisting of N-Z amine type A, 3%, dextrose, 1%; and agar, 1.5 %. Macroscopically, no aerial mycelia are evident; colonies are slightly raised, granular to weakly folded.Growth is fair, glistening, and no diffusible pigment is. produced. On an agar medium composed of yeast extract, 1% and glucose 1%, a rosecolored diffusible pigment is produced.The mycelia are regularly branched averaging 10~20 ju in length and 0.6 jjl in diameterNumerous chlamydospores are produced, up to 2ju in diameter. Conidia are not observed on the N-Z amine medium. The laboratory fermentation of M. rosaria is carried out in two stages, as follows: a) Germination stage: A loopful of M. rosariaculture from an agar slant is used to inoculate a 300-ml flask containing 100 ml of the following sterile medium: beef extract, 3 g; tryptose, 5g; yeast extract, 5g; dextrose, 1g; potato starch, 24g, calcium carbonate, 2g; tap water, 1,000ml. The flask and its contents are incubated for 72 hours at 35°C on a rotary shaker with 2-inch (5.1 cm) stroke at 280rpm. * Formerly named rosaramicin.

Verdamicin is a new aminoglycoside antibiotic isolated from fermentation broths of a species of the genus Micromonospora, M. grisea . It has been differentiated from other known related antibiotics by a variety of chemical and biological methods. Its in vitro and in vivo spectrum of activity appears to be similar to those of gentamicin and sisomicin.