NMO⋠TPB: a selectivity variation on the Ley-Griffith TPAP oxidation.

A non-hygroscopic tetraphenylborate salt of N-methylmorpholine-N-oxide (NMO) is reported (NMO⋅TPB), which modulates the standard Ley-Griffith oxidation such that benzylic and allylic alcohols are oxidised selectively. An attractive feature of this new protocol is that anhydrous conditions are not required for this selective tetra-n-propylammonium perruthenate (TPAP) oxidation, superseding the requirement of molecular sieves.

Adapted method for rapid detection and quantification of pathogen Campylobacter jejuni from environmental water samples.

Building on a previously developed workflow for rapid and sensitive pathogen detection by qPCR, this work has established a sample treatment strategy that produces consistent quantification efficiencies (QEs) for Campylobacter jejuni against a complex and highly variable sample matrix from a suburban river. The individual treatments most effective at minimizing the inhibitory effects of the sample matrix were pH buffering with HEPES (50 mM, pH 5.7) and addition of the surfactant Tween 20 (2% v/v). Unexpectedly, sample acidification (pH 4-5) resulting from the use of aged Tween 20 that had undergone partial hydrolysis, appeared to play a key role in enhancing QE. This effect could be replicated by direct pH adjustment with dilute hydrochloric acid and may be linked to the solubilization and removal of inhibitory particles at an acidic pH. While the effectiveness of each individual treatment method varied, a combined treatment of either HEPES buffer + Tween 20, or direct pH adjustment + Tween 20, consistently produced QEs of 60%-70% and up to 100%, respectively, over a sampling period of one year. The consistency and scalability of this workflow make it a suitable alternative to culture-based ISO methods for detecting Campylobacter spp.

Discovery of brevijanazines from Aspergillus brevijanus reveals the molecular basis for p-nitrobenzoic acid in fungi.

The brevijanazines are novel p-nitrobenzoylated piperazines isolated from Aspergillus brevijanus. Their structures were elucidated by spectroscopic analysis, X-ray crystallography and total synthesis. Heterologous biosynthesis, precursor feeding and in vitro microsomal assays unveiled the biosynthetic pathway to the brevijanazines, featuring a cytochrome P450 oxygenase that converts p-aminobenzoic acid to p-nitrobenzoic acid.