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.
Properties of plant nutrient: Comparison of two nutrient recovery techniques using liquid fraction of digestate from anaerobic digester treating pig manure.
Anaerobic digestate has valuable potential as organic fertilizer or soil amendment, given that it typically contains high amounts of plant nutrients, such as nitrogen, phosphate and plant hormones. In this study, ammonia stripping and vacuum evaporation were tested to compare their technical feasibilities and their effects on plant nutrient properties in the liquid fraction of digestate. Results of the batch experiments showed that the nutrient characteristics of liquid digestate, including total ammonia nitrogen (TAN), soluble P, gibberellic acid (GA), indoleacetic acid (IAA) and abscisic acid (ABA), were strongly dependent on the initial pH in both ammonia stripping and vacuum evaporation processes. A low plant nutrient concentration (TAN 137 mg · L(-1), soluble P 1.5 mg · L(-1), GA3/ABA 0.04) in the liquid digestate was achieved in the ammonia stripping process with Ca(OH)2 addition of 12 g · L(-1), whereas a high nutrient concentration (TAN 2998 mg · L(-1), soluble P 178.3 mg · L(-1), IAA 60.9 mg · L(-1) and GA3/ABA 0.4) was achieved in vacuum evaporation at a pH level of 6. According to the results, both ammonia stripping and vacuum evaporation can be used as an alternative of nutrient recovery techniques, which should be chosen based on the potential different applications of liquid digestate (e.g., soaking seed, increasing plant tolerance, and nutrients transportation).
A Comparison of the Effects of Autoclaved and Nonautoclaved Gibberellic Acid on Lemna perpusilla 6746.
Gibberellic acid was reported to inhibit flowering, reduce frond size, and increase the multiplication rate of aseptically cultured Lemna perpusilla 6746 when autoclaved with the medium (4), but there are no reports on the effects of nonautoclaved GA3 on this species. Since GA3 is unstable to heat (2), all or part of the reported effects of GA3 on L. perpusilla 6746 might be due to decomposition products formed during autoclaving (6). The results that follow show that auto