Phenolic diversity and antioxidant potential of different varieties of bamboo leaves using LC-ESI-QTOF-MS/MS and LC-ESI-QqQ-MS/MS.

Bamboo is a highly sustainable plant with a wide variety of leaves, yet little is known about its bioactive composition. Therefore, this study aims to characterize the phenolic profile and antioxidant capacity of 11 different varieties of bamboo leaves using liquid chromatography coupled with mass spectrometry. As a result, 81 phenolic compounds were tentatively identified, 29 of which were identified for the first time in the literature for bamboo leaves. The tentatively identified compounds fell into five classes (hydroxybenzoic and hydroxycinnamic acids, flavones, flavanones, and flavonols). The concentration of phenolic compounds ranged from 103 to 1291 mg/100 g. Among the provisionally identified compounds, there was a predominance of derivatives from the luteolin and apigenin group, with orientin and schaftoside being the majority in each group, respectively. The leaves also showed significant variation in antioxidant activity, highlighting the potential bioactive composition of bamboo leaves for future applications in the food industry.

Triple quadrupole-mass spectrometry protocols for the analysis of NBOMes and NBOHs in blotter papers.

NBOMe and NBOH are new psychoactive substances with potent activity on serotonin 5-HT2a receptors causing serious toxic effects, including serotonin toxidrome and death. The aim of this work was to develop a comprehensive MS/MS protocol, using triple quadrupole mass spectrometers coupled to LC and GC, for rapid screening and quantitation of NBOMes and NBOHs in seized blotter papers. Different scan methods (neutral loss, precursor ion or multiple reaction monitoring) were used to obtain structural information of phenylethylamine class. The developed protocol was validated for qualitative and quantitative analysis, showing a satisfactory limit of detection (1 ng/mL), with excellent selectivity, imprecision (intra and interday imprecision lower than 1.2 % RSD) and accuracy (between -7.1 and +5.6 %, n = 15), as well as bias values. The analysis of real samples shown that NBOH compounds were the most frequently detected, with concentrations ranging from 0.1 to 1,929 µg per blotter sample. Triple quadrupole mass spectrometers can be a useful tool for identification of new psychoactive substances. A comprehensive protocol using both LC-MS/MS and GC-MS/MS, with different scanning modes, have been developed and showed to be useful to screening NBOMe and NBOH in blotter papers.