Search

Pyrrolizidine alkaloids are secondary plant metabolites that have already been designated as a potential health risk due to their toxicity. Quinolones are antimicrobials related to bacterial resistance, one of the world's largest contemporary public health problems. This study searched for 22 pyrrolizidine alkaloids and 7 quinolones in honey available for sale in the state of Rio de Janeiro – Brazil – employing an analytical method based on LC-Q-TOF-HRMS. No quinolones were identified, while pyrrolizidine alkaloids were found in 39 out of 80 samples, mainly erucifoline (detected in 17% of the samples) and intermedine/lycopsamine (quantified in 27% of the samples). Considering the highest value found, 141.8 µg kg−1 for senecionine and a consumption of 20 g of honey per person per day, the dietary exposure reached 47.3 ng kg−1, resulting in a MOE value of 5.010, that might lead to a risk for human health. [ABSTRACT FROM AUTHOR]

This article presents the determination of eight pyrrolizidine alkaloids (PAs) by LC-MS/MS in honeys, pollen, and Senecio brasiliensis (Asteraceae) samples, all from Santa Catarina state, Brazil. In addition, the Box-Behnken design was used to perform an optimized sample preparation on pollens and S. brasiliensis parts. Senecionine and its N-oxide, besides retrorsine N-oxide, were determined in six of the seven honeys samples. Pollen from species of the Asteraceae, Fabaceae, and Boraginaceae families were found with greater predominance in three of the seven honeys samples. In these three honeys samples were also found the highest PAs levels. In beehive pollen, flower, and leaf of S. brasiliensis, the total levels of PAs and their N-oxides reached 221, 14.1 × 104, and 14.8 × 104 mg kg−1, respectively. In honeys, these compounds are chemical contaminants and therefore undesirable when the sum exceeds 71 µg kg−1, according to EFSA. On the other hand, although PAs are naturally present in plant and pollen of some species (Senecio, Crotalaria, Bacharis, Ecchium, Mimosa scabrella, Vernonia), it is important to monitor their levels in plants but also in honeys, and other beehive products since these compounds are transferred to the final product. [ABSTRACT FROM AUTHOR]

Analysis of physicochemical parameters, phenolic compounds, total reducing capacity, free radical scavenging, and antimicrobial potential was performed in 14 samples of honey from six different species of stingless bees from Brazil. The results of the physicochemical properties showed high moisture (24.28%–38.20% wt/wt), free acidity above 50 meq/kg for most honey samples, reducing sugars ranging from 58.79% to 73.01% (wt/wt), 5‐hydroxymethylfurfural (5‐HMF) below the limit of quantification (0.074 mg/L), diastase activity from <3 to 70.91 Göthe units, and electrical conductivity values varying from 0.13 to 0.84 mS cm−1. In addition, 12 phenolic compounds were quantified, being taxifolin (

Abstract: Gas chromatography–mass spectrometry analysis of seeds from 28 species of Crotalaria from Brazil (sections Calycinae, Crotalaria, Chrysocalycinae and Hedriocarpae) showed that pyrrolizidine alkaloids (PAs) are important as chemotaxonomic markers at the infrageneric level. The sections Calycinae and Crotalaria were characterized by 11-membered macrocyclic monocrotaline-type PAs. In the section Chrysocalycinae, a single species in the subsection Incanae, C. incana, showed integerrimine, a 12-membered macrocyclic senecionine-type, as main PA. The group close to the subsection Stipulosae (C. micans and C. maypurensis) showed distinctive PA patterns: C. micans presented mainly the 12-membered macrocyclic integerrimine, and C. maypurensis the unusual 7-hydroxy-1-methylene-8-pyrrolizidine. In the group close to the subsection Glaucae, the PAs with otonecine as the necine base were the main alkaloids, except in C. rufipila which showed an assamicadine-like PA (monocrotaline-type). The section Hedriocarpae showed main 12-membered macrocyclic senecionine-type PAs. [Copyright &y& Elsevier]