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Fermentation conditions are described for the production of the antitumor antibiotic 7-(S)-brefeldin-A (brefeldin-A) in liquid culture byEupenicillium brefeldianum, (B. Dodge) Stolk and Scott, ATCC 58665. An analytical hplc method was developed which allowed rapid quantitation of the compound during fermentation. A kilogram of brefeldin-A was isolated from a fermentation at the 6800-liter scale.

A comparative study of the short range effect of run time (mobile phase volume - pH 2.0) on column parameters (k', α, Rs and peak asymmetry) of three different reversed phase columns was undertaken. The columns evaluated were C-18 nucleosil (low density carbon loading), C-18 ultracarb (high density carbon loading), and C-30 (medium density carbon loading). After an average run time of eleven hours using a buffered mobile phase at pH 2.0 and basic solutes, the results showed that the C-30 and C-18 high carbon loading columns gave better peak asymmetry than the C-18 nucleosil column, while there was no appreciable change in α or Rs with run time using the three test columns. A noticeable change in retention time between the three columns was observed.

The anti-histaminic drug methapyrilene hydrochloride, which induces liver tumors in rats, was labeled with tritium by exchange and administered at a dose of 21 mg containing 700 µCi to each of 15 male Fischer rats. At 1 h, 6 h, 14 h, 24 h, and 44 h after treatment three rats were killed and their livers, pancreas, kidneys, and lungs were removed. The pooled organs were homogenized and DNA, RNA, and soluble protein were isolated from each. The extent of interaction of radioactive methapyrilene with liver nucleic acids was exceedingly small and did not differ significantly from the binding to nucleic acids in kidney, lung, or pancreas, which are not target organs of this carcinogen in rats. Binding of radioactivity to soluble proteins of the liver was considerable and substantially greater than in the other organs. If the mechanism of carcinogenic action of methapyrilene involves covalent interaction with DNA this must be at a very low and highly specific level.

The separation of a mixture of structurally similar compounds was achieved using a cation exchange column and a buffered mobile phase rich in an organic modifier 50-75%. The addition of different modifiers to the mobile phase affected not only the selectivity but the resolution.

Factors influencing captures of the male Grapholitha molesta (Busck) by traps baited with its synthetic sex pheromone, (Z)-8-dodecenyl acetate, and dodecyl alcohol (a synergist) were investigated. Of the 5 trap designs tested, the Zoecon Pherotrap 1, with both top and bottom sections, caught the most moths. Traps at, heights of 3 and 6 ft caught best; comparatively few moths were taken at 9 ft and almost none at ground level. Of 4 concentrations of a 1:10 combination of pheromone + synergist, 0.8 μl pheromone + 8 μl synergist caught the most moths; of 7 combinations of pheromone + synergist, 2 μl each of pheromone + synergist caught best. Addition of (Z)-8-dodecenyl alcohol to the pheromone + synergist mixture depressed moth captures. Response to the attractant was greatest between 8 and 9 PM, with response continuing at a lesser pace through the night. Most importantly, the addition of a small percentage of the E isomer to the pheromone resulted in enhanced attraction; thus, the mixture of synergist + pheromone containing 1.7% E isomer caught only 20 moths vs. 505 caught by a similar mixture with 6.7% of the E isomer.