534 The Philippine Journal of Science 1923 



chaulmoogra oil and some of its derivatives have a direct antag- 

 onistic action upon acid-fast bacilli, and experimental evidence 

 allows us to deduce more definitely than does clinical observation 

 that this action is not to be conceived as purely bactericidal, 

 but rather in the sense of Walker's hypothesis. It can be 

 shown by laboratory experiments that the direct antiseptic 

 action of chaulmoogra oil is specific, in as much as chaulmoogra 

 inhibits the growth of acid-fast bacilli in dilutions in which it has 

 no such effect on the growth of non-acid-fast bacteria. 



An attempt on the part of chemists to eliminate inert sub- 

 stances from chaulmoogra oil and its derivatives and thus 

 concentrate the active principle, or to isolate the particular acid 

 that would be most effective, yielded numerous preparations 

 which appear to exert variable degrees of antiseptic action upon 

 Bacillus tuberculosis in vitro. 



It is claimed that valuable oils in chaulmoogra therapy of 

 leprosy show a specific rotation of polarized light of about + 50°. 

 In view of this claim it seemed of interest to compare the oils 

 obtained from various closely related species of plants with each 

 other as to their growth-inhibiting effect and, if quantitative 

 differences were found, to study their relation to their power of 

 rotating the plane of polarized light and other physical and 

 chemical properties. 



It is not my intention to claim that the results of such labor- 

 atory experiments as are presented herewith can be applied 

 directly to the treatment of leprosy, but in view of the wide 

 use of chaulmoogra therapy study of the experimental chemo- 

 therapy of this and related drugs should be continued. 



These experiments were begun shortly after the paper of 

 Walker and Sweeney came to my attention, because of the 

 bearing this work has on the problem of chaulmoogra treat- 

 ment of leprosy. The present investigation is an attempt to 

 answer, by experimental laboratory evidence, questions on the 

 following and other points in the problem of chemotherapy of 

 infectious diseases that are caused by acid-fast bacilli. 



*. JiiAriitfaMJjiJNTS IN VITRO 



L. The growth-inhibiting activity of chaulmoogra oil and its derivatives. 

 .. Comparison of the growth-inhibiting power of chaulmoogra with that 



of other vegetable and animal oils, rare and common. 

 !. The disinfecting power of the vapors of certain vegetable oils. 

 ■■■ A survey of certain organic compounds as to their growth-inhibiting 



activity toward acid-fast bacilli in vitro, 

 i. An inquiry into the mechanism and nature of the growth-inhibiting 



effect of chaulmoogra and other vegetable oils. 



