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It has been adequately demonstrated by Mann and coworkers ( 1-4) that elaboration of fructose by the accessory sex organs ceases after castration and that it is readily resumed following the administration of testosterone. We were able to confirm and extend their findings(5,6). In a series of transfers of sperm from normal seminal plasma Ito plasma of castrate animals treated with testosterone and other steroids, it was shown by us( 5 ) that the rate of fructose utilization decreased by as much as 70% even though the seminal fructose level was within or above the normal range. This justifies the speculation that the composition of seminal plasma obtained from such animals differs from that of the intact animal either because one or more constituents are lacking or because of a shift in the quantitative relationship of sume of the plasma componmts. Thus, it was desirable to more thoroughly characterize the nutrients in seminal plasma elaborated under various physiological conditions. I. Chromatography of seminal carbohydrates. I t also became apparent that as far as the carbohydrate pattern of seminal plasma is concerned, the chemical methods used have not been adequate. While Mann and his coworkers( 1-3) demonstrated that the seminal sugar is not glucose but fructose, they also stated that other sugars may be present in minute quantities. Since, to our knowledge, no attempt has been made to verify these findings by more sensitive methods such as paper partition chromatography, it seemed pertinent that this procedure be employed.Experimental. The semen or seminal plasma was extracted with 80% ethanol and the precipitated proteins were removed by centrifugation. The supernatant extract was reduced *This work was supported in part by Ciba Pharmaceutical Products, Summit, N. J., A m u r and Co., Research Division, and the Bureau of Dairy Industry, Agricultural Research Administration, Department of Agriculture.to dryness at 50°C and the dry residue diluted with 10% isopropyl alcohol to one-half the original volume. This extract concentrate was chromatographed in one dimension using the method outlined by Patton( 7 ) .I t was evidmt that only one sugar, namely fructose, was found in the semen of these bulls regardless of whether they were normal, vasectomized, or castrated and restituted with testosterone. It was also evident that the separation of the various sugars on the papergram is specific and critical whether this was done with mixtures of pure sugars or when such sugars were singly or in mixtures incorporated with the seminal plasma to be chromatographed. The addition of glucose to a semen sample containing fructose resulted in the appearance of 2 definite spots, glucose always being in the lower position. The concentration of sugars in spots obtained on paper following the development with either the Seliwanoff reagent or aniline hydrogen phthalate was measured with a Densichron. We were able to correlate reasonably well the fructose values obtained by chromatography with results of standard chemical analyses...

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In a laboratory-scale system, dentrification activity of a heterotrophic microbial starter culture changed when different lots of poly-3-hydroxybutyrate-co-3-hydroxyvalerate (P(HB-co-HV)) were used as the solid carbon source in the heterotrophic denitrification reactor. In this study, possible influences of physical and chemical properties of commercially produced P(HB-co-HV) (Biopol) on biofilm formation and metabolic activity of a denitrifying starter culture were investigated. These parameters indicate the polymers' suitability for the application as the matrix substance in the bioreactor. No differences in microstructure were detected between the different lots of polymers. Growth inhibitory effects by chemical additives were found in the case of triacetine, which was included as a plasticizer in seven of eight tested lots. The amount of hydroxyvaleric acid in the polymer was not assumed to affect denitrification activity. Relevant differences could be detected regarding primary adhesion of the starter culture Pseudomonas sp. strain 2nIII. It showed good adsorption properties to hydrophobic substances with a dependence on precultivation conditions. Pseudomonas sp. strain 2nIII degraded poly-3-hydroxybutyrate acid homopolymer and P(HB-co-HV) copolymers but was unable to break up poly-3-hydroxyvaleric acid. A possible reason for these findings is the substrate specifity of the polyhydroxyalkanoate depolymerase.