1970 Volume 16 Issue 3 Pages 181-189
It was found that Pediococcus cerevisiae ATCC 8081 can grow and produce acid on μg amounts of thymidine instead of mμg amounts of folinic acid SF (citrovorum factor) to a considerably better extent with a "thymidine enhancement factor".
The "factor" present in some microbiological media was identified as an effect of Tween 80 present in the medium. Similar effect was obtained also by other non-toxic detergents and was considered to be surface tension lowering, since it was (a) unspecific for the chemical nature of the "factor" (b) of the "all-or-none" type (c) dependent on a defined water/liquid interfacial tension.
The bearing of changes in surface tension of the environment causing selective nutritional effects was discussed.