FUNGI AND MODERN AFFAIRS — RAMSBOTTOM 325 



isolation. It was indeed a strange chance which led to the contamina- 

 tion of a laboratory culture by an apparently uncommon mold (origi- 

 nally described from decaying hyssop in Norway) ; and that the 

 laboratory should be that of one who was curious in antibiotic phenom- 

 ena and who, convinced of the value of his discovery, kept not only 

 the original plate but also maintained the mold in culture. Further, 

 it was fortunate that the original Oxford isolation of crude penicillin 

 contained little if any toxic substances, with the result that Florey 

 and the Oxford team were so soon able to announce almost undreamed- 

 of achievements. This general freedom from association with harm- 

 ful products incidentally has also characterized home-grown cultures 

 of penicillin. 



Penicillin is the most active bacteriostatic substance so far known ; 

 but the difficulty of obtaining sufficient quantities and its unstable 

 quality have led to the search for similar mold products, and has also 

 stimulated general research. There are many such products known, 

 but few are sufficiently nontoxic for use. Flavicin from Aspergillus 

 flavus and gigantic acid from A, giganteus are most similar to peni- 

 cillin in their chemical and biological properties. 



Raistrick and his colleagues have tested many of the compounds 

 they had isolated and all new substances which were obtained. The 

 product of the fermentation of Penicillium patulum (originally iso- 

 lated from sheep dung in France) was considered promising and was 

 sent to W. E. Gye, who is studying the effects of various substances on 

 cancer cells. As he was suffering from a cold, he used it on himself 

 with most satisfactory results. Extended trials show that it is able 

 to cure a promising number of cases of one form of the common cold. 

 It has since been shown that patulin is identical with clavacin and 

 clavatin obtained from Aspergillus clavatus, and claviformin, from 

 Penicillium clavifonne and Aspergillus giganteus. It is not surpris- 

 ing that the same chemical substance should be formed by several 

 fungi — indeed, this is what one would expect. What is of greater 

 interest is that it is also produced by Penicillium expansum. Van 

 Luijk in 1938, studying the diseases of grasses caused by species of 

 Pythium, found a difference in plants grown in sterilized and non- 

 sterilized soil. He isolated a number of fungi from the soil and 

 from the air and tested their influence on the growth of Pythium,. 

 He found that Penicillium expamsum was the most markedly anti- 

 biotic, and adopting Fleming's procedure, obtained sterilized filtrates : 

 these inhibited the growth of Pythium debaryanum at dilutions of 

 1 : 1,280. He did not isolate the antifungal substance, which Anslow, 

 Raistrick, and G. Smith (1943) have shown to be patulin. When 

 the fungus was added to garden soil infected with Pythiwn, seedlings 

 remained healthy instead of damping off. 



