GB841696A - A new antibiotic designated r 285 - Google Patents

Abstract

<PICT:0841696/IV(b)/1> <PICT:0841696/IV(b)/2> A new antibiotic designated R285 is produced by fermenting in submerged aerobic conditions Streptomyces R285. ATCC 13064 T in an aqueous nutrient medium containing a source of carbon, an assimilable nitrogen source and mineral salts at a temperature between 22 DEG and 37 DEG C., and preferably 22 DEG to 26 DEG C., for 48 to 120 hours, at a pH 6.0 to 7.5. Suitable nitrogenous substances are corn steep liquor, barley or wheat malt extract, casein enzymatic hydrolysates, peanut meal, soybean meal, cottonseed meal, ammonium sulphate and sodium nitrate. Carbon sources are glucose, maltose, lactose, galactose, glycerol, mannose, sodium succinate, dextrin and starch. Mineral salts are calcium carbonate, phosphate, sulphate and magnesium, and traces of cobalt, zinc, copper, manganese and iron ions. Preferred is 1 to 3% nitrogen source, 1 to 6% carbon source, 0.1 to 2% sulphates, 0.1 to 1.0% calcium carbonate and 0.0001-0.0005% trace elements. The antibiotic R285 is isolated by adjusting the pH to 1.5 to 3.0, filtering-off the mycelium, adjusting to pH 7.0 to 8.5 and extracting with a solvent such as ethyl acetate. The ethyl acetate extract may be dried, and concentrated in nitrogen to allow the antibiotic to precipitate. Alternatively, an aqueous extract of the ethyl acetate extract may be made at pH 2.0 to 2.5, the extract adjusted to pH 7.5 to 8.0 and, then re-extracted with ethyl acetate. The antibiotic is active against grain-positive bacteria such as mycobacteria, it is basic forming salts with inorganic and organic acids such as hydrochloric, picric, picrolonic, styphnic (trinitroresorcioul), phosphomolybdic acids and helianthin i.e. p-dimethylaminophenylazobenzene sulphuric acid; it is only slightly soluble in water and organic solvents in general; it is stable in acid or neutral solution; contains carbon 58,00%, hydrogen 6,8% and nitrogen 13,57%; empirical formula C25H35N5O7 melting point 165-167 DEG C.; [d]d 20 DEG C. + 122 DEG (C1 0,5 in. 0,1 N HCL); molecular weight 520; Rf by paper chromatography 0,70 (butanol acetic acid-water) 0,55 (3% aqueous ammonium chloride); ultraviolet spectrum in 0,1 N.HCl shows maxima at 256-258 mm (E1%c.m. 315) and 313-315 mm (E1%c,m. 276) minimum 282 mm (E1%c.m. 124); infrared spectrum shows maxima in cm-1 at the following frequencies: 3330, 1650, 1625, 1605, 1570, 1485, 1378, 1308, 1260, 1185, 1138, 1080, 1058, 1040, 992, 938, 845, 805, 788 and 760.