452 ANNUAL REPORT SMITHSONIAN INSTITUTION, 194 5 



as penicillic acid (C s H 10 O 4 ) from P. cyclopium and P. puberulum; 

 kojic acid (C 6 H G 4 ) ; puberulic acid (C 8 H 5 6 ) ; and puberulonic acid 

 (C 8 H 4 6 ). 



CLAVACIN 



A significant ketone antibiotic is clavacin, which has many aliases, 

 such as patulin, claviformin, and clavatin. Obtained from Aspergil- 

 lus clavatus, P. patulwm, and P. claviforme, it has the formula 

 C T H 6 4 . Great enthusiasm was evidenced at one time in Great Britain 

 because of its reported value against both gram-positive and gram- 

 negative organisms and for its apparent action upon the secondary 

 organisms which complicate the common cold. Later experimental 

 use by other workers failed to substantiate the early expectations that 

 it would prove a specific for the common cold, but the subject is still 

 an open one with many authorities, according to Raistrick. 



Chaetomium eochliodes is the source of chaetomin, which has also 

 been isolated but never purified. It has limited usefulness but may 

 ultimately prove of more value. Citrinin, Ci 3 H 14 5 , is a quinone 

 from P. citrinum and from other species of Aspergillus. It is not as 

 active as the other antibiotic agents and is more toxic. 



ACTINOMYCIN 



Of the various species of organisms from which antibiotics may 

 be developed, the actinomyces are the most promising, for over one- 

 fifth of all these species are capable of producing antibiotic substances 

 of some type. 



One of the most promising of the group is actinomycin A. Ob- 

 tained from A. antibioticus, it is a pigmented ring compound with 

 the formula C41H56N80U. Although it is toxic to animals, its com- 

 plex nature provides possible avenues of approach whereby the 

 chemist may substitute in the formula and bring about a reduction in 

 toxicity and a further increase in physiologic activity. 



Various actinomyces species produce actinomycetin, a polypeptid 

 of indefinite composition which is comparatively nontoxic but of only 

 limited activity. It acts more or less as a proteolytic enzyme. 



NOTATIN 



Penicillin B, notatin, and penatin are terms used to describe a glucose 

 aerohydrogenase from P. notatum. It has only slight activity and 

 specificity against a limited number of organisms. None of this entire 

 group of antibiotics, with the exception of penicillin and tyrothricin 

 concentrate, have achieved sufficient recognition to warrant com- 

 mercial production for therapeutic use. 



