Sensitive chromatographic methods were developed for the quantitative analysis of secondary metabolites in Hypericum perforatum (St. John's wort) and Rhodiola rosea (Golden root, rose root) extracts. Sample preparation methods were developed for plant, cell culture and biotransformation suspension matrixes. High performance liquid chromatography (HPLC) was used for the separation of analytes, a...

We present a novel probe design for ambient laser-based mass spectrometry imaging combining electrospray ionization (ESI) and atmospheric pressure chemical (APCI) in single probe, compatible with commercial laser ablation (LAESI) instrument. Here we describe the considerations features, as well an in-house developed data processing routine designed to extract accurate from post-ionization exper...

A simple, fast, and sensitive method for the extraction through direct saponification, separation, quantification, and identification of 12 cholesterol oxidation products (COPs) and cholesterol in a single isocratic, normal-phase, high-performance liquid chromatography (HPLC) was developed. Three detectors were compared for determination of COPs and cholesterol in fish samples: refractive index...

Narcissus is widely used for cut flowers and potted plants, and is one of the most important commercial bulbous flowers in the floricultural industry. In this study, ten carotenoid and eighteen flavonoid compounds from the perianths and coronas of fifteen narcissus cultivars were measured by HPLC-APCI-MS/MS and UPLC-Q-TOF-MS/MS. Among these, six carotenoids, a total of seventeen flavonols and c...

trans-Resveratrol and trans-piceid were found for the first time in dark chocolate (at least 0.4 ppm trans-resveratrol and 1 ppm trans-piceid) and cocoa liquor (at least 0.5 ppm trans-resveratrol and 1.2 ppm trans-piceid). Because these compounds are highly sensitive to light, a specific extraction procedure was required to recover them, involving delipidation with toluene and cyclohexane and e...

Numerous plant species worldwide including Palicourea marcgravii and Tanaecium bilabiatum in Brazil cause sudden death and are known to contain monofluoroacetate (MFA). Other species in Brazil including some species traditionally assigned to Mascagnia but now properly called Amorimia species and other Palicourea species are reported to cause sudden death in livestock and are suspected to contai...

Bis(2-hydroxyethylthio)alkanes and bis(2-hydroxyethylthioalkyl)ethers are important biological and environmental degradation products of sulfur mustard analogs known as sesqui- and oxy-mustards. We used atmospheric pressure chemical ionization mass spectrometry (APCI MS) to acquire characteristic spectra of these compounds in positive and negative ionization modes. Positive APCI mass spectra ex...

Gas chromatography-atmospheric-pressure chemical ionization-time-of-flight mass spectrometry (GC-APCI-TOFMS) was compared to GC × GC-electron ionization (EI)-TOFMS, GC-EI-TOFMS, GC-chemical ionization (CI)-quadrupole mass spectrometry (qMS), and GC-EI-qMS in terms of reproducibility, dynamic range, limit of detection, and quantification using a mix of 43 metabolites and 12 stable isotope-labele...