DESCRII'TIOXS OF ANTIBIOTICS 



325 



70°C" for U) iniiuites, then extracted with methanol, 

 bvitanol, ethanol, n- or isopropaiiol, or methanol - 

 ethanol (1:1) (5). Fractional precipitation with 

 ethyl acetate. Fractional precipitation from 

 methanol with ether (1). II. Methanolic or ace- 

 tone extracts of mycelium concentrated in. vacuo. 

 Residue suspended in 0.85 per cent NaCl-butanol 

 (1:1). Precipitate at interface washed with saline, 

 dissolved in warm methanol, cooled, and repre- 

 cipitated with saline. Precipitated from methanol 

 with ethyl acetate (30). III. Purified by treat- 

 ment with hot ethyl acetate, then extracted with 

 warm 70 per cent aqueous acetone. Slow cooling 

 gives an amorphous precipitate, followed by active 

 needles. Distribution of material in a biphasic 

 system (butanol-methanol-water-hexane, 50:50: - 

 35:15) and air evaporation yield crystals at the 

 interface with little inactivation (2). IV. Forms a 

 complex with CaCU in methanol, giving separation 

 from impurities. Addition of water to this CaCli- 

 methanol solution precipitates crystalline nysta- 

 tin (25, 34). V. Broth and mycelium extracted 

 with n-butanol. Extract distilled off in vacuo at 

 <45°C. Residue extracted with nuMlianol as in 

 Step I (30). VI. Isopropanol added to whole 

 l)roth; pH adjusted to 5 with H:iP()4; stirred; pH 

 adjusted to 7 with NaOH; and mixture filtered. 

 Isopropanol evaporated off in riicuo at <30°C to 

 orecipitate nystatin (29). Precipitate slurried in 

 20 per cent aqueous isopropanol containing 0.5 per 

 cent sodium hexametapyrophosphate (weight per 

 voliune) at 60°C, and cooled to 10°C with mild 

 agitation to precipitate nystatin (34). 



Chemical and physical properties: Amphoteric 

 conjugated tetraene. Pale yellow microcrystals 

 (9) or needles (26). Gradual decomposition above 

 160°C. No melting up to 250°C (2). Soluble in 

 pyridine, propylene glycol, dimethylformamide, 

 and dimethylacetamide (2, 9). Soluble with in- 

 activation in glacial acetic acid, 0.05 A' methanolic 

 HCl, or NaOH. Solubility in polar solvents in- 

 creased in presence of 10 to 20 per cent water. 

 Slightly soluble in methanol, ethanol, butanol, and 

 dioxane. Insoluble in water, ether, chloroform, 

 hexane, and acetone (2, 12) . Ultraviolet absorption 

 spectrum maxima (methanol) at 235, 291, 304, and 

 319 mfx (E = 298, 536, 754, and 596, respectively) 

 (30). Infrared spectrum given in reference 30. 

 [al'ti" = +21° (pyridine) or —10° (glacial acetic 

 acid) (2). Positive Benedict, Molisch, and car- 

 bazole tests. KMn04 , iodine-KI, and Bro-CCU 

 decolorized. Slowly positive Schift' test. Negative 

 FeCls , biuret, ninhydrin, Millon, phenol, Fehling, 

 Tollen, and 2,4-dinitrophenylhydrazine tests. 

 Blue color with FeCl3-K.3Fe(CN)6. In concentrated 

 H2SO4 , color changes from violet to blue to black 



(2, 12, 30). I'ink in phosphoric acid; yellow in 

 hydrochloric acid (30). Withstands 55°C for 1 hour 

 at pH 5 to 8 in a methanolic solution. Inactivated 

 by heat, light, oxygen, and excessively high or 

 low pH (2, 30). Neutral equivalent, 956 (glacial 

 acetic-perchloric acids) (2). Potassium and so- 

 divuii salts insoluble in water and iuistal)le; hy- 

 drochloride is water-soluble and stable (2). 

 Nitrogen-containing moiety, which is also present 

 in amphotericin B, is mycosamine (27). Nystatin 

 C46H77N()ic, : C = 58.5%i H = 8.23%; N = 1.64%; 

 C — CH:i = 5.86%. Contains no methoxyl, acetyl, 

 or N — CH3 groups. Contains the same chro- 

 mophore as methyl-^-parinarate. Contains a diene 

 system in addition to its tetraenic chromophore, 

 carboxyl, and lactone functions (12, 25). 



Biological activili/: In ritro: Active on fungi and 

 yeasts (1, 30), including a variety of plant patho- 

 gens (33). Iiuictive on bacteria (1). Molhiscacide 

 (10). Active on Endamoeba histolytica (9). Activity 

 reversed by cysteine (2). Development of resist- 

 ance is negligible. Cross-resistance with other 

 polyenic antibiotics (15). In vivo: Active on 

 moniliasis in mice, ral)bits, and chickens (3, 13, 24) 

 and on histoplasniosis, coccidioidomycosis, sporo- 

 trichosis, cryptococcosis, blastomycosis, and 

 Mucor pusilliis infections, all in mice (4, 7, 8, 32). 

 In plants: Protects beans from anthracnose 

 (Colletotrichum lindcinu/hiainnn) and partially 

 protects them from lust [I' roinyces phaseoli var. 

 typica). Reduces post -harvest decay of straw- 

 berries (Botrytis and Rhizopus) (22) and peaches 

 (19). Activeon downy mildew of cucumber (Pseudo- 

 peronospora cubensis) (21) and broccoli (Perono- 

 spora parasitica) (23). Active on jjeach brown rot 

 (Sclerotinia fructicola) (20). Active on Botrytis 

 infection of orchids (Cattlcya) (38), roses (35), and 

 tulips (36). Some control of pink snow mold 

 {Fusarium nivali) (31). 



Toxicity: Crude nystatin: LD,5o (mice) 20 to 26 

 mg per kg intraperitoneally. Subcutaneously, 2 

 gm per kg is tolerated, but with necrosis and 

 induration at site of inoculation (1). Ten fig per 

 ml is nontoxic to HeLa, monkey kidney, and 

 normal human epithelial cells (11). Purified ny- 

 statin: LD.Mi (mice) 8 to 14 mg per kg intraper- 

 itoneally; (rats) 24.2 to 24.6 mg per kg. Mice 

 tolerate 2.3 to 3.5 gm per kg orally (9). 



Utilization: Proj^hylaxis against yeast over- 

 growth during administration of antibacterial 

 antibiotics (6). Moniliasis. Intestinal amebiasis 

 (9). Coccidioidomycosis (16). Trichophytosis and 

 epidermophytosis (14). Does not give rise to 

 resistant Candida strains during treatment (18). 

 Some effect in j)reventing moniliasis in poultry 

 (39). 



