250 



DESCRIPTIONS OF ANTIBIOTICS 



lymphosarcoma (69), and Eagles KB epidermoid 

 carcinoma (76). Moderately inhiliits Bashford 

 carcinoma 63, adenocarcinoma E 0771, carcinoma 

 1025, Wagner and Ridgeway osteogenic sarcomas, 

 Harding-Passey melanoma, Flexner-Jobling car- 

 cinoma (69), and RC mammary carcinoma (70). 

 Slight inhibition of Crocker sarcoma 180 in mice 

 (32). Inhibition (at 1 mg per day) of weight in- 

 crease in mice inoculated with Ehrlich ascites 

 carcinoma, an effect which ceases with withdrawal 

 of the drug (40). In plants: Cycloheximide con- 

 trols: Powdery mildew of: beans {Erysiphe poly- 

 goni) (3) ; dewberry (Sphaerotheca humuli) (20) ; 

 onion (17); squash {Erysiphe cichoracearum) (19); 

 rose {Sphaerotheca pannosa var. rosae) (5); grape 

 {Uncimula necator) (49); and cherry {Podosphaero 

 oxyacanthae) (46). Leaf spot of cherry (9) and ar- 

 tificial infections with Coccomyces hiemalis of 

 cherry trees (34). Smut (covered) of oats {Ustilago 

 kolleri) (21) and wheat {Tillctia sp. (30) and T. 

 foetida (75)). Rust of: wheat (Puccinia graminis 

 var. tritici) (43); mint (Puccinia menthae) (17); 

 turf (stem rust, Puccinia graminis) (48) ; safflower 

 {P. carthami) (54) ; red cedar {Gymnosporangium 

 juniperi-virginianae) (45); white pine (63); apple 

 leaf (cedar rust) (42) ; and asparagus (semicar- 

 bazone used) (74). Turf diseases: Sclerotinia ho- 

 meocarpa and Hehninthosporium sp. infections 

 (18, 28); "fading out" {Curvularia lunata) (35); 

 leaf spot phase of "melting out" {Helmintho- 

 sporium vagans) (59). Miscellaneous: Sphacelotheca 

 sorghi infections of sorghum (38); Rhizoctonia and 

 V erticillium infections of potato stems (36) ; brown 

 rot of peach {Sclerotinia fructicola) (49) ; rot of 

 Delicious apples (73); oak wilt (Endoconidiophora 

 fagacearum) (44); wood-rotting fungi, including 

 Poria microspora (16); cucumber scab iCladospo- 

 rium cucunierinuin) (10); l)lack leg of cabbage 

 {Phoma lingam) ((iO) ; derrite disease of coffee 

 {Phyllosticta coffeicola) (61); Dactylium dendroides 

 mildew infection of mushrooms (56); post-harvest 

 decay {Botrytis and Rhizopus) of strawberries 

 (64). Other activity: At very low concentrations, 

 increases seed germination of oats and Madrid 

 sweet clover, sprout growth of oats, and top 

 growth of l)oth oats and clover. Added to soil, 

 increases bacterial and actinomycete population 

 and nodules on sweet clover, but decreases the 

 fungal population (33). Holds down mold count 

 on harvested black raspberries (27). 



Toxicity: LDso (mice) 150 to 160 mg per kg in- 

 travenously (1) and subcutaneously (31); 375 mg 

 per kg orally (31). LD50 (guinea pigs) (iO mg per 

 kg subcutaneously; (rabbits) 17 mg per kg in- 

 travenously^; (cats) 4 mg per kg intraperitoneally; 



(rats) 2.7 mg per kg subcutaneously, 5 mg per kg 

 oralh-, and 2.5 mg per kg intravenously (12, 31). 

 Intravenous injection of 1 mg per kg in dogs is 

 followed by vomiting within a few minutes (7). 

 Cycloheximide was found to be very repellent to 

 rats (12). Plants: Inhibits germination of the 

 following seeds b}' soaking for 4 hours (ppm) : 

 radish (100), pea (>100), wheat (100). Soaking for 

 30 minutes at 100 ppm has no effect on seed ger- 

 mination of cantaloupe, spinach, or cucumber 

 seeds (6). Toxic to tomato and bean plants at 1 

 ppm, wheat at 10 ppm, geranium and peach at 100 

 ppm; not toxic to strawberry at 1000 ppm (applied 

 as sprays) (14, 30). Stunts alfalfa seedlings at 0.4 

 yug per ml in a soil solution (29). pH of the spray 

 was found to be a factor in to.xicity of cyclohexim- 

 ide (37). Nontoxic when applied to cantaloupe 

 plants as a 4-ppm spray (47). Use of chlorophyll in 

 cycloheximide sprays reduces the toxicity of the 

 antibiotic on beans without affecting antifungal 

 activity (65). Injurious to roses at concentrations 

 of 0.1 to 0.4 ppm when sprayed on the young leaves 

 (42). Produces cytological aberrations, including 

 prophase inhibition, in Pisum sativum (39) and 

 Allium cepa (11) root cells, as well as in HeLa 

 cells at 12.5 /xg per ml (57). Human beings: Nausea 

 observed following cycloheximide injections in 

 human beings (7). Toxic by intrathecal route, but 

 not intravenously (23). Crystalline cycloheximide 

 and its concentrated solutions are highly irritating 

 to the skin, producing a reddening and sloughing 

 (62). 



Utilization: Plant disease. Used commercially 

 for control of turf diseases and cherry leaf spot 

 (62). Usefulness of cycloheximide is reduced by 

 the fact that at effective therapeutic levels it is 

 often toxic to the host plant (55). Sweet wine 

 preservation (31). Therapeutic effect in one case 

 of cryptococcic meningo-encephalitis, and gave a 

 remission in one ca.se of coccidioidal meningitis 

 (24). 



sTEREOisoMER.s OF CYCLOHEXIMIDE: Cyclohe.xim- 

 ide has four centers of asymmetry permitting 

 isomers. 



Naramycin B 



Produced by: Streptomyces sp. differing from S. 

 griseus. This culture also produced cycloheximide 



'(71). 



Chemical and physical properties: Colorless 

 plates; m.j). 109-1 10°C. Ultraviolet absorption 

 spectrum maximum at 292.5 m^u (log e, 1.49) and 

 a shoulder at 232 m/i (methanol). Infrared data 

 given in reference 71. [alo" = +50.2° (c = 2 per 



