Abstract Lychnophora pinaster, known as arnica-mineira, is endemic to campos rupestres, at risk of extinction. The present study aimed to characterize the ecogeography and phenolic constituents of 11 L. pinaster populations collected in the mesoregions North, Jequitinhonha, Metropolitan of Belo Horizonte and Campos das Vertentes in the state of Minas Gerais, Brazil. Phenolic constituents were identified and quantified by Ultra-high performance liquid chromatography- mass spectrometry. Lychnophora pinaster occurs in sites at high altitude (700 and 1498 m), annual rainfall of up to 1455 m, soils with low fertility and predominantly loamy texture. Therefore, it can be considered tolerant to acidic soils, with low availability of nutrient. The most abundant substances in all populations were vitexin (18 – 1345 ng/g) and chlorogenic acid (60 – 767 ng/g). The 11 populations formed four groups in relation to the phenolic constituents, with group 1 consisting of the populations of the North Mesoregion (GM, OD) and Jetiquinhonha (DIMa), group 2, the Metropolitan of Belo Horizonte (SRM, NLSC, SM, RPS, CTRA), group 3, the North Mesoregion (ODMa and DI), and group 4, the Campos das Vertentes (CC). Among the populations, only those from the Metropolitan of Belo Horizonte showed correlation of soil properties with phenolic constituents.

ABSTRACT This study compared the influence of mechanical damage and drying on the chemical composition of Mikania glomerata Spreng. and Mikania laevigata Sch.Bip. ex Baker, Asteraceae, leaves. Leaves were collected 1-24 h after damage. Oven-drying at 40ºC and shade-drying at ambient temperature were compared to lyophilization. Samples were extracted in 70% ethanol and analyzed by ultra-high-performance liquid chromatography with mass spectrometry. Significant (p < 0.05) increases of caffeoylquinic acids were observed in damaged leaves of both species and coumarin decreased in M. laevigata, indicating stress. Although the final water content was similar, the drying method affected the leaf composition. In shade-dried leaves of M. laevigata coumarin decreased and the presence of umbelliferone was observed; caffeoylquinic acid contents increased for 288 h in in both species. Apparently, enzymes were inactivated after 6 h in oven drying, stabilizing their chemical composition, while shade drying allowed enzymatic and microbial activity to continue; illustrating the importance of post harvesting procedures on the quality of medicinal plants.

ABSTRACT Geopropolis is a special type of propolis produced by stingless bees. Several pharmacological properties have been described for different types of geopropolis, but there have been no previous studies of the geopropolis from Melipona mondury. In this study, we investigated the antioxidant, antibacterial, and antiproliferative activities of M. mondury geopropolis, and determined its chemical profile. The antioxidant activity was determined using in vitro ABTS·+, ·DPPH, and β-carotene/linoleic acid co-oxidation methods. The antibacterial activity was determined using a microdilution method with Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin-resistant S. aureus. The antiproliferative effect was determined in tumor cell lines using the Alamar Blue assay. The chemical profile was obtained using UHPLC-MS and UHPLC-MS/MS. The butanolic fraction had the highest concentration of phenolic compounds and more potent antioxidant properties in all assays. This fraction also had bacteriostatic and bactericidal effects against all bacterial strains at low concentrations, especially S. aureus. The hexane fraction had the highest antiproliferative potential, with IC50 values ranging from 24.2 to 46.6 µg/mL in HL-60 (human promyelocytic leukemia cell) and K562 (human chronic myelocytic leukemia cell), respectively. Preliminary chemical analysis indicates the presence of terpenes and gallic acid in the geopropolis. Our results indicate the therapeutic potential of geopropolis from M. mondury against inflammatory, oxidative, infectious, and neoplastic diseases.

Abstract In Brazil, Mikania glomerata Spreng. and M. laevigata Sch. Bip. ex Baker, Asteraceae, known popularly as guaco, are widely used for colds and asthma. Although coumarin is adopted as the chemical marker of both species, it was not always detected in M. glomerata, for which chlorogenic acid was identified and quantified instead. The purpose of this study was to develop and validate a method to quantify both coumarin and chlorogenic acid and apply it to extracts of plants identified as M. glomerata, M. laevigata, or as guaco, to determine the pattern of composition of these two species and to observe differences between oven-dried and lyophilized leaves. A method using ultra-high resolution liquid chromatography–mass spectrometry (UHPLC–MS) in the full scan mode was validated for selectivity, matrix effect, linearity, limits of detection and quantification, precision and accuracy. The concentration of coumarin varied between species and samples, therefore these two species should not be used interchangeably. The concentration of chlorogenic acid was also determined for all samples. The UHPLC–MS method permitted the quantification of coumarin and chlorogenic acid in 16 samples of guaco and several commercial samples were possibly misidentified.