Abstract: New polyether antibiotic A80190, its acyl and alkyl ester, acyl ester and urethane derivatives, and salts thereof, are useful antibacterial and anticoccidial agents and increase feed-utilization efficiency in animals. Methods of making A80190 by culture of Actinomodura oligospora NRRL 15877 and synergistic compositions of the A80190 compounds with nicarbazin, 4,4'-dinitrocarbanilide, certain napthalenamine and benzenamine compounds and metichlorpindol are also provided.

Abstract: Antibiotic A47934 is produced by submerged, aerobic fermentation of new Streptomyces toyocaensis NRRL 15009. The antibiotic is active against gram-positive bacteria in vitro and in vivo. It promotes growth in poultry and swine and serves to enhance feed efficiency in ruminant animals having a developed rumen.

Abstract: Antibiotic A47934 is produced by submerged, aerobic fermentation of new Streptomyces toyocaensis NRRL 15009. The antibiotic is active against gram-positive bacteria in vitro and in vivo. It promotes growth in poultry and swine and serves to enhance feed efficiency in ruminant animals having a developed rumen.

Abstract: Antibiotic A-7413 complex, comprising a major microbiologically active factor A, and minor active factors B, C, and D, is produced by fermentation of Actinoplanes sp. NRRL 8122. The individual factors are isolated and separated by extraction and chromatography. The A-7413 antibiotics are antibacterial agents. The A-7413 complex and A-7413 antibiotic compounds are also useful as growth-promoting agents and in the control of dental caries and acne.

Abstract: Tylactone (20-dihydro-20,23-dideoxytylonolide), which has the formula: ##STR1## and specified acyl ester derivatives thereof are useful intermediates in the preparation of macrolide antibiotics.

Abstract: Tunicamycin is produced by the cultivation of Streptomyces chartreusis Calhoun and Johnson, 1956, NRRL 12338. Methods of recovering tunicamycin and for separating and isolating individual factors A.sub.1, A.sub.2, B.sub.1, B.sub.2, C.sub.1, C.sub.2, D.sub.1 and D.sub.2 from tunicamycin complex are described.

Abstract: Antibiotic A-21978 complexes, in particular the A-21978C complex, comprising microbiologically active, related factors, C.sub.0, C.sub.1, C.sub.2, C.sub.3, C.sub.4, and C.sub.5. A-21978 complex and A-21978C complex are produced by submerged aerobic fermentation of Streptomyces roseosporus NRRL 11379. The individual A-29178C factors are separated and isolated by chromatography. The A-21978 and A-21978C complexes, the A-21978C factors, and pharmaceutically acceptable salts thereof are antibacterial agents and improve growth promotion in poultry.

Abstract: Method and compositions for treatment of swine dysentery with antibiotic A-32887 (K-41). Antibiotic A-32887 is produced by submerged aerobic fermentation of Streptomyces albus NRRL 11109.

Abstract: The new microorganism Streptomyces lydicus DeBoer et al., NRRL 12034 and the fermentation process for preparing narasin by submerged aerobic fermentation of this organism.

Abstract: Methods and compositions for treatment of coccidiosis in poultry with antibiotic A-32887 (K-41). Antibiotic A-32887 is produced by submerged aerobic fermentation of Streptomyces albus NRRL 11109.

Abstract: Mycarosyltylactone (5-O-mycarosyl-20-dihydro-20,23-dideoxytylonolide) which has the formula: ##STR1## 3,4'-diacyl ester derivatives of mycarosyltylactone wherein each of said esters is an ester of a monocarboxylic acid or a hemi-ester of a dicarboxylic acid, each of 1 to 18 carbon atoms, and the corresponding 3-acyl ester derivatives of tylactone, are useful intermediates in the preparation of macrolide antibiotics. New methods for making tylactone and the 3-acyl ester derivatives of tylactone are provided.

Abstract: Tunicamycin is co-produced with antibiotic A-23187 by the cultivation of Streptomyces chartreusis NRRL 3882. Methods of recovering tunicamycin and for separating and isolating individual factors A, B, C, and D from tunicamycin complex are described.

Abstract: Antibiotic A-21978 complexes, in particular the A-21978C complex, comprising microbiologically active, related factors C.sub.0, C.sub.1, C.sub.2, C.sub.3, C.sub.4, and C.sub.5. A-21978 complex and A-21978C complex are produced by submerged aerobic fermentation of Streptomyces roseosporus NRRL 11379. The individual A-29178C factors are separated and isolated by chromatography. The A-21978 and A-21978C complexes; the A-21978C factors; and pharmaceutically acceptable salts thereof are antibacterial agents and improve growth promotion in poultry.

Abstract: Deoxynarasin antibiotic complex, comprising 20-deoxynarasin and 20-deoxy-epi-17-narasin, is produced by submerged aerobic fermentation of Streptomyces aureofaciens NRRL 11181. 20-Deoxynarasin and 20-deoxy-epi-17-narasin are separated and isolated by chromatography. The deoxynarasin complex, 20-deoxynarasin and 20-deoxy-epi-17-narasin are antibacterial and anticoccidial agents and also increase feed-utilization efficiency in ruminants.

Abstract: Deoxynarasin antibiotic complex, comprising 20-deoxynarasin and 20-deoxy-epi-17-narasin, is produced by submerged aerobic fermentation of Streptomyces aureofaciens NRRL 11181. 20-Deoxynarasin and 20-deoxy-epi-17-narasin are separated and isolated by chromatography. The deoxynarasin complex, 20-deoxynarasin and 20-deoxy-epi-17-narasin are antibacterial and anticoccidial agents and also increase feed-utilization efficiency in ruminants. 20-Deoxynarasin and its salts are cardiotonic agents.

Abstract: Antibiotic A-7413 complex, comprising a major microbiologically active factor A, and minor active factors B, C, and D, is produced by fermentation of Actinoplanes sp. NRRL 8122. The individual factors are isolated and separated by extraction and chromatography. The A-7413 antibiotics are antibacterial agents. The A-7413 complex and A-7413 antibiotic compounds are also useful as growth-promoting agents and in the control of dental caries and acne.

Abstract: A method for the topical treatment of acne with antibiotic A-201A and A-201A compositions for acne are disclosed.

Abstract: Deoxynarasin antibiotic complex, comprising 20-deoxynarasin and 20-deoxy-epi-17-narasin, is produced by submerged aerobic fermentation of Streptomyces aureofaciens NRRL 11181. 20-Deoxynarasin and 20-deoxy-epi-17-narasin are separated and isolated by chromatography. The deoxynarasin complex, 20-deoxynarasin and 20-deoxy-epi-17-narasin are antibacterial and anticoccidial agents and also increase feed-utilization efficiency in ruminants.

Abstract: Antibiotic A-21978 complexes, in particular the A-21978C complex, comprising microbiologically active, related factors C.sub.0, C.sub.1, C.sub.2, C.sub.3, C.sub.4, and C.sub.5. A-21978 complex and A-21978C complex are produced by submerged aerobic fermentation of Streptomyces roseosporus NRRL 11379. The individual A-29178C factors are separated and isolated by chromatography. The A-21978 and A-21978C complexes; the A-21978C factors; and pharmaceutically acceptable salts thereof are antibacterial agents and improve growth promotion in poultry.

Abstract: Antibiotic A-21978 complexes, in particular the A-21978C complex, comprising microbiologically active, related factors C.sub.0, C.sub.1, C.sub.2, C.sub.3, C.sub.4, and C.sub.5. A-21978 complex and A-21978C complex are produced by submerged aerobic fermentation of Streptomyces roseosporus NRRL 11379. The individual A-29178C factors are separated and isolated by chromatography. The A-21978 and A-21978C complexes; the A-21978C factors; and pharmaceutically acceptable salts thereof are antibacterial agents and improve growth promotion in poultry.