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Some results of our studios on transformation of steroids by mixed culture fermentation are presented in this paper. Arthrobacter simplex was paired in turn with each of the following: Streptomyces roseochromogenes, Curvularia lunata, Absidia coerulea, and Aspergillus ochraceus. The steroid substrates examined for multiple transformation were 16α-hydroxy-cortexolone, 16α-hydroxy-cortexolone 16,17-acetonide, 9α-fluorohydrocortisone, 9α-fluorohydrocortisone 21-acetate, and 9α-fluorohydrocortisone 21-hemisuccinate. The effects of media, steroid substrate, and microbial interaction in a mixed culture on the induction and repression of steroid transforming enzymes were unique to each case studied. The reaction mechanism of the multiple steroid transformation was also found to vary from one mixed culture system to another. Two different reaction mechanisms were observed, namely, consecutive and parallel. In the former, one of the two enzymatic reactions always preceded the other, while in the latter, two different enzyme reactions occurred simultaneously, thereby giving rise to two different intermediates. Multiple transformation of steroids by a single step mixed culture fermentation has potential economic advantages.

SUMMARY: Some factors affecting induction and repression of steroid-transforming enzymes were studied in single and mixed cultures of Arthrobacter simplex, Nocardia restrictus and Streptomyces roseochromogenes. In single or mixed cultures induction and repression of 1-dehydrogenase, 16α-hydroxylase, and 20-ketoreductase were found to be dependent on the type of steroid substrate and the composition of the medium. In mixed cultures patterns of growth as well as enzyme induction and repression were altered by culture interaction. An observation having practical significance was that 16α-hydroxylation and 1-dehydrogenation of 9α-fluorohydrocortisone to triamcinolone could be done, in a single fermentation operation, by a mixed culture of A. simplex and S. roseochromogenes. The practicality of this transformation derives from the fact that 20-ketoreductase, an enzyme responsible for the production of undesirable by-products in cultures of A. simplex, was completely repressed in the mixed culture system. Although growth of A. simplex was suppressed by metabolites of S. roseochromogenes, conversion of steroids with this mixed culture was reproducible and controllable within a wide range of ratios of organisms in the starting mixtures.

To understand the effects of vasectomy on men, 1080 men were interviewed an average of 3.7 years after having had this operation. These men were grouped according to whether they privately paid for their operation or received it through a government program. The average age of these subjects was 37.8 years, and they had an average of 4.7 children. Reasons for vasectomy included economic considerations and the desire to limit their family. This type of operation was selected due to its permanance and reliability. Many men were motivated by family counselors or by the mass media. 68% had discussed the operation with their wives. 16% of the men had fears of impotence after the operation. Most were operated under a local anesthesia, and were not hospitalized. 57% did not bother to stay at home in recovery. Pain was encountered by 25% during the operation. Sexual activity was resumed in 3 weeks, with little change reported in eating or sleeping habits. Coital frequency decreased from 1.92-1.70 times/week. 90% of the men said they would recommend the operation to others.

Orange and yellow-colored light emission has been achieved at room temperature in the same elecroluminescent device (ELD) made on GaN thin films codoped with Er and Eu. The GaN film was grown by molecular-beam epitaxy on Si (111) substrates using solid sources for Ga, Er and Eu and a plasma source for N2. Simple Schottky devices were fabricated on the GaN films using indium–tin oxide (ITO) transparent electrodes. ELD spectra show that the yellow and orange colors result from the combination of green emission from Er (537, 558 nm) and red emission from Eu (621 nm). A color change was observed with applied bias, producing yellow at higher bias (−100 V) and orange at lower bias (−70 V). We have fabricated both relatively small (∼250 μm) and large (1.45 mm) ELDs. Parameters for the chromaticity diagram were calculated to be x=0.382, y=0.605 for the yellow emission and x=0.467, y=0.523 for the orange emission. This work shows the possibility of achieving any intermediate color in the spectrum from green to red...

Present study investigate the effect of enzyme supplementation, methods (applied to rumen or enzyme treated diet) compared with no enzyme diet, on rumen fermentation and apparent nutrient digestibility in a 3×3 Latin square design with three rumen cannulated Korean Native goats. In situ rumen degradation kinetics was studied in three rumen cannulated Holstein steers. Three diets were, no enzyme, 1% enzyme in rumen and 1% enzyme in diet. The enzyme was sprayed onto forage, and the forage: concentrate ratio was 30:70. Degradation kinetics was studied with three enzyme levels (0, 1 and 2%, w/w) and four pre-treatment times (0, 1, 12 and 24 h). Results suggested that enzyme application method did not affect rumen fermentation, ruminal enzyme activity and total tract apparent digestibility. Nutrient degradation rate and effective degradability of DM, NDF and ADF increased with increasing enzyme level and pre-treatment times. Degradation of nutrients was affected by enzymes levels or pre-treatment times. Therefore, it is probable that the improved degradation may be due to the supplemented exogenous hydrolytic enzymes under a certain condition. (Asian-Aust. J. Anim. Sci. 2003. Vol 16, No. 3 : 389-393)

These two volumes are the proceedings of the eighth symposium organized by the Committee on Thermophysical Properties of the American Society of Mechanical Engineers. The symposia are held every three or four years. The many papers collected in these volumes summarize the work of scientists and engineers who produce reference data on the properties of materials. These include both thermodynamic and transport data on gaseous, liquid, and solid compounds under wide ranges of temperature and pressure. Some report new data. Others report new techniques of measurement that enable one to obtain more accurate data, data under difficult conditions, and/or data on new materials. There is a substantial representation of theorists who are increasingly successful in correlating raw data and obtaining reliable new data by extension from the raw data based on theory. The need for these activities to be continuously pursued and supported is clearly evident in the article by Ho and Touloukian (Vol. II, p. 419). They give many examples of data, drawn from the published literature, that are entirely incorrect both quantitatively and qualitatively. They show clearly that use of some of these incorrect data can lead to disastrous results in practical applications. With the development of new materials, the demand for reliable thermophysical data will increase. The wide availability of computers makes it possible to accumulate large bodies of data in a short time. In addition, major advances have been made in the last decade on the statistical mechanical theory of dense fluids and of the critical phenomena. 2o3

We have developed a qualitative method to assay for the presence of 2-deoxystreptamine in hydrolysates of crude aminoglycoside preparations using a 2-deoxystreptamine-requiring idiotrophic mutant. The assay involves (i) incubation of a 2-deoxystreptamine-requiring mutant with 1 mg of a hydrolyzed preparation from a crude unknown antibiotic mixture per ml, and (ii) examination of the resultant incubation mixture for production of antibiotic(s) by disk assay.

A hybrid structure of rosaramicin and mycinamicin has been mutasynthesised and found to be highly active against gram positive organisms.

Treatment of N-2-ethylhexyl-N-trimethylsilylamine with dinitrogen tetroxide affords 2-ethylhexyl nitrate in fair yield.

Oxidation of sulphinamides with 1-chlorobenzotriazole with a heterogeneous buffer produces novel imidosulphinamides and not sulphonimidoyl chlcrides.

L-Threonine was converted in ten steps into potassium (2R,3R)-1-methoxy-3-tetrahydropyranyloxybutane-2-diazoate (10), which was then alkylated with n-octyl iodide. Removal of the tetrahydropyranyl group afforded L-dihydroelaiomycin in an overall yield of 8% for twelve steps. The synthetic product was compared with its D-enantiomer, prepared by reduction of natural elaiomycin over 5% rhodium–alumina.

A versatile asymmetric synthesis of either enantiomer of open-chain, chiral sulphoxide is described.