Proof of formation of an unstable conjugated triene on decomposition of gibberellin A3 in water
It has been shown by the methods of1H NMR and high-performance liquid chromatography with recording of UV spectra that in aqueous solutions of gibberellin A3, via gibberellenic acid, an unstable conjugated triene having λmax 326 nm is formed which is readily converted into allogibberic acid and is isolated as a mixture (1:2) with this acid. In the1H NMR spectrum of the triene, confirming its structure, spin-spin coupling both of the H-5 proton and of the protons of the methyl group with all the H-1, H-2, and the H-3 protons is observed. The precursor of allogibberic acid has been ascribed the structure of (−)-13-hydroxy-19,20-dinorgibberella-1,3,9,16-tetraen-7-oic acid with a conjugated 1,3,9-trienic system.
Anaerobic Digestion and Storage Influence Availability of Plant Hormones in Livestock Slurry
Anaerobic digestion slurry (ADS) is typically applied as a liquid fertilizer and soil amendment because it contains high concentrations of plant nutrients. For many years, macronutrients such as nitrogen and phosphorus in ADS has been widely studied, whereas little attention has been paid to plant hormones. Lab-scale batch experiments were conducted to evaluate the effect of anaerobic digestion (AD) on plant hormones (gibberellic acid (GA3), indoleacetic acid (IAA), abscisic acid (ABA)) in three typical animal manures (chicken, dairy, and pig). Results from the lab-scale batch experiments revealed that ADS contained higher concentrations of plant hormones than the original animal manures. Subsequently, quantitative analysis of samples from large-scale continuously fed biogas plants verified the high contents of plant hormones in ADS. However, the storage experiment demonstrated a significant loss of plant hormones in ADS prior to land application because of decomposition and transformation. Specifically, ...
The primary structure of oligonucleotides. Partial apurinization as a method to determine the positions of purine and pyrimidine residues
The absence of specific endonucleases represents an important problem in determination of primary structure of deoxyribo oligonucleotides. As a possible solution of this problem we proposed earlier [l] a novel approach based upon incomplete (random) specific chemical modification followed by determination of position of the modified residues in oligonucleotide. The validity of the approach was illustrated by a method of determination of the positions of cytosine residues in deoxyribo oligonucleotide [ 11. Now we propose a method to find the positions of purine and consequently pyrimidine residues in deoxyribo polyand oligonucleotides.