HPLC/ESI-MS analyses of alcohol solutions of ampicillin and amoxicillin have shown that the two drugs react very readily with alcohols (methanol and ethanol) at room temperatures, without the presence of any catalyst. Products of methanolysis were detected even when methanol was used as a mobile phase, in HPLC/ESI-MS analysis of a water solution of ampicillin and amoxicillin. Therefore, neither...

The aim of the study was to obtain transformed roots of Rhaponticum carthamoides and evaluate their phytochemical profile. Hairy roots were induced from leaf explants by the transformation of Agrobacterium rhizogenes strains A4 and ATCC 15834. The best response (43%) was achieved by infection with A4 strain. The effects of different liquid media (WPM, B5, SH) with full and half-strength concent...

Dry leaf extracts of eastern teaberry (Gaultheria procumbens L.) were evaluated as a source of bioactive phytocompounds through systematic activity testing and phytochemical profiling. The antioxidant efficiency was tested using five complementary in vitro models (DPPH; FRAP; linoleic acid (LA) peroxidation assay; O2•- and H2O2 scavenging tests) in parallel with standard antioxidants. The 75% m...

Two mass spectrometry methods, high-performance liquid chromatography combined on-line with electrospray ionization mass spectrometry (HPLC-ESI-MS) and electron-capture (EC) dissociation tandem mass spectrometry (MS-MS), were applied for structural analysis of bovine and human osteocalcins. Osteocalcin contains gamma-carboxyglutamic acid (Gla) residues, which bind metal ions, among its amino ac...

Researchers are increasingly turning to label-free MS1 intensity-based quantification strategies within HPLC-ESI-MS/MS workflows to reveal biological variation at the molecule level. Unfortunately, HPLC-ESI-MS/MS workflows using these strategies produce results with poor repeatability and reproducibility, primarily due to systematic bias and complex variability. While current global normalizati...

Harvested longan (Dimocarpus longan Lour.) fruit are susceptible to decay caused by both bacterial and fungal infections. Ochratoxin A (OTA) is a kind of mycotoxin produced by a number of fungi. In this study, OTA was extracted from longan fruit pulp by 80% methanol and then loaded on C-18 solid-phase extraction columns. The extract solution was then analyzed by high-performance liquid chromato...

Different separation (HPAEC, RP-HPLC, CE) and identification (MALDI-TOF-MS, ESI-MS(n)) techniques were compared to analyse oligosaccharides obtained after incubation of xyloglucan with endo-glucanase. It was possible to analyse xyloglucan oligosaccharides with each technique. Several techniques, including off line (HPAEC-MALDI-TOF-MS) or online (CE-ESI-MS(n), RP-HPLC-ESI-MS(n)) connection provi...

Using the HPLC/PDA/ESI/MS method, a comparative analysis of rhodionin (RH) was undertaken in order to conduct a qualitative and quantitative study in 38 batches of fourteen species of Rhodiola for quality control purposes. Alongside of this RH analysis, a simultaneous determination of salidroside (SA), tyrosol (TY), and gallic acid (GA) was carried out. Rhodiola plants are a popularly used ethn...

Antidesma bunius is an edible berry fruit with many benefits, such as natural antimicrobials, anticancer, dyes, etc. However, data on chemical content in the still limited. The purpose of this research to identify volatile compounds fruit. We extracted and analyzed A. fruit’s using GC-MS HPLC–DAD-ESI-MS methods. Forty-nine representing 99.91% total chromatogram’s relative peak area were detecte...