|Abstract or Summary
- Propionic acid, live Propionibacterium shermanii, and
Dimethyl Fumarate (DMF) were tested for their stimulatory or
inhibitory efects on yeast, bacteria, and molds. The amount
of propionic acid required for inhibition of molds was
strain specific and equal to or less than that required for
inhibition of the yeasts. Live P. shermanii cultures grown
for 96 hours inhibited the growth of yeast and one species
of bacteria but were not effective against molds. DMF inhibited all the species against which it was tested and is
proposed to be a potent medicinal agent for treatment of
vaginal and topical infections.
Stability testing of DMF in human plasma, rabbit blood,
human vaginal secretions (in normal saline), normal saline,
and in water maintained at 85°C and 45°C was conducted.
Degradation of DMF followed first order kinetics in human
plasma and had a half life of about 154 minutes. Degradation of DMF in rabbit blood could be fit to a second
order kinetic model and had an approximate half life of 10
minutes. DMF had a half life of about 21 hrs in vaginal
secretions whereas only 25 percent DMF degraded in 22 hours
in normal saline. In water, ninety-five percent of DMF
degraded at 85°C, whereas 72 percent DMF remained intact at
45°C at the end of an eight week period.
An attempt was made to study the pharmacokinetics of
DMF in rabbits by administering DMF orally and as an intra
venous infusion. Detectable amounts of DMF were not found
in rabbit blood.
Dosage forms containing DMF or propionic acid were pre
pared and buffered at pH 4.5. Suppositories, ointments and
foam aerosols were tested against Candida utilis. The sup
pository containing DMF inhibited the yeast growth completely. Aerosols also inhibited the growth of yeasts at
higher dilutions, but at lower dilutions there was growth
observed at the edges of the plates indicating uneven
spraying of aerosols. Ointment containing 3% propionic
acid inhibited C. utilis completely whereas 0.5% DMF did
not inhibit the yeast growth, which is surprising, and may
indicate either that degradaton of DMF had occured or DMF
was not released from the vehicle. This was a broad preliminary study of propionic acid,
DMF, and metabolites of Propionibacterium shermanii as
potential medicinal agents and gives guidance for further
detailed investigation of these compounds.