Descriptions of Antibiotics 



A b i k o V i ro in vein 



Produced by: Strepiuiiiyces abikoensian (1 , 2), also 

 known as S. abikoensis (3). This culture also 

 produces a heptaene antifungal substance and 

 viomycin (7). S. rubescens (1, 2); S. reticidi var. 

 [atumcidicus (5), said to resemble <S'. abikocusnin 

 (6); Slreptomyces sp. (4). 



Synonyms: Latumcidin (6), virocidin (?). 



Method of extraction: I. Broth-filtrate treated 

 with ethyl acetate at neutrality. Extract con- 

 centrated and chromatographed on alumina after 

 addition of petroleum ether; column developed 

 with petroleum ether, then with ethyl acetate. 

 Exceedingly unstable; glucose must be added 

 before the solvent can be removed in vacuo (1, 2). 

 II. All procedures are carried out in the cold 

 luider N-i. Broth is adjusted to pH 8, and extracted 

 with methyl isobutyl ketone. Back-extraction into 

 water at pH 2.0. Extraction from water with ether 

 at pH 8, and re-extraction into water at pH 2.0. 

 Extraction of aqueous layer with methyl isobutyl 

 ketone at pH 8, followed by addition of concen- 

 trated H)S04 to precipitate the active substance. 

 Re-crystallized from methanol or ether (5). 



Chemical and physical properties: Unstable 

 basic substance (5). Sublimes during freeze-drying 

 (1, 2). The sulfate forms white needles, m.p. 

 U0-14O.5°C (decomposition) (5) or 120-125°C 

 (decomposition) (6). Soluble in water and meth- 

 anol. Slightly soluble in ethanol, butanol, and 

 acetone. Insoluble in other organic solvents (5). 

 Ultraviolet absorption spectrum maxima at 230 

 to 240 niM and 334 to 340 m^ in 0.1 N HCl; or at 

 244 to 246 niM and 280 to 291 m^ in 0.1 N NaOH 

 (6). Infrared spectra given in ref. 6. [a]p = +148.9° 

 (c = 0.1 per cent in 0.1 A'' NaOH). Positive diazo, 

 Bayer, and bromine tests (5). Conflicting reports 

 on Molisch and ToUen silver mirror tests. Nega- 

 tive FeCl.? , Fehling, Ehrlich, Sakaguchi, nin- 

 hydrin, biuret, and xanthoproteic tests, and tests 

 for primary, secondary, and amyl amines. Turns 

 red after decomposition (1, 2, 5). Most unstable at 

 pH 4 to 7 (5) and less stable in water and ethanol 

 than in other solvents. Readily auto-oxidizetl (1, 2). 

 CnHiaO-iNHeSOi- C = 46.6%; H = 5.13%; () = 

 31.18%; N = 4.99%; S = 12.10% (5). 



Biological activity: Active on western and 

 eastern equine encephalomyelitis viruses in con- 

 tact tests, but not on Venezuela equine encephalo- 

 myelitis or on Japanese B encephalitis viruses 

 (1, 2, 6). Weakly active on bacteria and myco- 

 bacteria. Conflicting reports on antifungal ac- 



tivity (1, 2, 5). Active on Tetrahymena at 5 )ug 

 per ml (5). 



Toxicity: LDoo (niice) 8 mg per kg (1, 2) or 17.3 

 mg per kg (5) intravenouslj', and 100 mg per kg 

 subcutaneously (1, 2). 



References : 



1. Umezawa, H. et al. Japan. Med. J. 4: 



331-346, 1951. 



2. Umezawa, H. et al. J. Antibiotics (Japan) 



5: 469-476, 1952. 



3. Okami, Y. J. Antibiotics (Jai)aii) o: 477- 



480, 1952. 



4. Umezawa, H. et al. Jajjan J. Med. Sci. & 



Biol. 6: 261-268, 1953. 



5. Sakagami, V. et al. J. Antibiotics (Japan) 



11 A: 6-13, 1958. 

 (). Sakagami, Y. et al. J. Antibiotics (Japan) 



11 A: 231-232, 1958. 

 7. Arai, T. et al. Antibiotics & Chemotherapy 



7: 435-442, 1957. 



Aburaniycin 



Produced by: Slreptomyces aburaviensis. 



Synonym: Similar to aureolic acid, but differs in 

 chemical tests. 



Method of extraction: Broth adjusted to pH 9.5 

 and filtered. Filtrate extracted at pH 2.0 with 

 ethyl acetate. Ethjd acetate back-extracted with 

 water at pH 9.0. Chromatography on alumina 

 and development with 80 per cent methanol. 

 Active fractions concentrated in vacuo. Addition 

 of water to concentrate precipitated aburamycin. 

 Re-crystallization from aqueous ethanol. 



Chemical and physical properties: Weakly acidic 

 substance. Yellow crystals; m.p. 163-165°C. Very 

 soluble in ethanol, acetone, ethyl acetate, butyl 

 acetate, butanol, and chloroform. Insoluble in 

 water, ether, benzene, ligroin, and petroleum 

 ether. C = 55.57%; H = 7.54%; O = 36.89%. 

 No N, S, or halogen. Positive Molisch, Fehling, 

 Benedict, Tollen, Seliwanoff, anthrone, and orcin 

 tests. Negative biuret, xanthoproteic, ninhydrin, 

 Tollen phloroglucine, FeCls , Folin, and tyrosine 

 reactions. [a]o = +24.56° (c = 1 per cent in 

 methanol). Ultraviolet absorption spectrum 

 maxima at 230, 276, and 410 m/i with weak maxima 

 at 320, 330, and 350 m/i (95 per cent ethanol); or 

 229, 276, and 410 ran with weak maxima at 316 and 

 330 niM (0.01 N HCl); or 234, 278, 316, and 410 m^ 

 (0.01 N NaOH). Infrared spectrum given in 

 reference 1. More stable at alkaline than acid pH. 



Biological activity: Active on gram-positive 



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