RESUMO
Pyrrolizidine alkaloids (PAs) are secondary metabolites produced by over 6000 plant species worldwide. PAs enter the food chain through accidental co-harvesting of PA-containing weeds and through soil transfer from the living plant to surrounding acceptor plants. In animal studies, 1,2-unsaturated PAs have proven to be genotoxic carcinogens. According to the scientific opinion expressed by the 2017 EFSA, the foods with the highest levels of PA contamination were honey, tea, herbal infusions, and food supplements. Following the EFSA's recommendations, data on the presence of PAs in relevant food were monitored and collected. On 1 July 2022, the Commission Regulation (EU) 2020/2040 came into force, repealed by Commission Regulation (EU) 2023/915, setting maximum levels for the sum of pyrrolizidine alkaloids in certain food. A total of 602 food samples were collected from the Italian market between 2019 and 2022 and were classified as honey, pollen, dried tea, dried herbal infusions, dried herbs, and fresh borage leaves. The food samples were analyzed for their PA content via an in-house LC-MS/MS method that can detect PAs according to Regulation 2023/915. Overall, 42% of the analyzed samples were PA-contaminated, 14% exceeded the EU limits, and the items most frequently contaminated included dried herbs and tea. In conclusion, the number of food items containing considerable amounts of PAs may cause concern because they may contribute to human exposure, especially considering vulnerable populations-most importantly, children and pregnant women.
Assuntos
Mel , Alcaloides de Pirrolizidina , Gravidez , Animais , Criança , Feminino , Humanos , Alcaloides de Pirrolizidina/análise , Cromatografia Líquida , Espectrometria de Massas em Tandem , Mel/análise , Plantas/metabolismo , Chá , Contaminação de Alimentos/análiseRESUMO
A bioguided separation of Lepechinia graveolens (Reg.) Epling. (Lamiaceae) for antioxidant activity was carried out. The ethyl acetate fraction (EAF) from the methanolic extract was chromatographed on Sephadex LH-20 affording five active fractions. The radical scavenging activity of each fraction, as well as that of the isolated compounds, was tested using three different methods. The major isolated antioxidant compounds were identified as luteolin-7-O-glucuronide, rosmarinic acid, and rosmarinic acid methyl ester by means of 1H and 13C NMR and mass spectrometry. Twenty other minor phenolic compounds were determined by liquid chromatography-negative electrospray ionization tandem mass spectrometry. They included hydroxycinnamic acid derivatives, flavonoids and phenolic diterpenes. The major phenolic compound was found to be rosmarinic acid, which was quantitatively determined by high-performance liquid chromatography (HPLC)-diode array detector (DAD). The content of rosmarinic acid was 2.8% (referred to dry weight), this amount being around 30% of the total phenolic content (TPH) of the crude extract. It can be concluded that the antioxidant activity of Lepechinia graveolens was mainly due to rosmarinic acid, which allows this plant species to be considered as a potential new source of this well known natural antioxidant.