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Development of a sensitive high-performance liquid chromatography-diode array detection assay for the detection and quantification of the beauveria metabolite oosporein from submerged culture broth and bio-control formulations.

Christoph Seger·Sonja Sturm·Tobias Längle·Waltraud Wimmer·Hermann Stuppner·Hermann Strasser
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Abstract

A sensitive high-performance liquid chromatography-diode array detection (HPLC-DAD) assay is described for the detection and quantification of the Beauveria metabolite oosporein from fungal culture broth and two biocontrol agent formulations. In all cases, analyte recovery was achieved with a Britton-Robinson buffer system at pH 5.5 diluted with methanol 3:7 (v/v) (BR5.5-MeOH). The HPLC-DAD assay, using a binary solvent gradient with acidic modifiers and detecting the metabolite at 287 nm, showed linearity over 3 orders of magnitude and a limit of detection (LOD) of 6.0 +/- 2.3 microg of oosporein/L of BR5.5-MeOH. The oosporein content of the representative fungal culture broth samples and two Beauveria formulations (Melocont-Pilzgerste and Melocont-WP) was found to be 504.7 +/-13.6 mg of oosporein/L of culture filtrate, 7.4 +/- 0.6 mg of oosporein/kg of Melocont-Pilzgerste, and 38.2 +/- 1.3 mg of oosporein/kg of Melocont-WP with recovery rates of 93 +/- 2, 99 +/- 8, and 92 +/- 3%, respectively.

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BenzoquinonesChromatography, High Pressure LiquidCulture Media, ConditionedHordeumHypocrealesPest Control, BiologicalSensitivity and SpecificityJournal ArticleResearch Support, Non-U.S. Gov't

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Christoph Seger, Sonja Sturm, Tobias Längle, Waltraud Wimmer, Hermann Stuppner, Hermann Strasser. 2005-03-09. Development of a sensitive high-performance liquid chromatography-diode array detection assay for the detection and quantification of the beauveria metabolite oosporein from submerged culture broth and bio-control formulations.. https://doi.org/10.1021/jf048232v

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