Products made by bees are well-known for their beneficial properties and nutritional value. This association has been proven by scientific studies that describe their composition and biological activities. The aim of this study is to portray the state of the art on research regarding stingless bee honey. The search for standards that guide the trade of these products is still portrayed as a future perspective, since there are significant differences in relation to honey from Apis mellifera and it often requires additional treatments. stingless bees / honey quality / chemical composition

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In this study, we investigated the chemical compositions and antioxidant and antimicrobial activities of propolis produced by the stingless bee Frieseomelitta longipes and the honeybee Apis mellifera collected from colonies in North Brazil. In terms of volatile composition, both mono-and sesquiterpenes were detected in the propolis of F. longipes while only sesquiterpenes were detected in that of A. mellifera. Out of 50 volatiles identified in all samples, 26 were found exclusively in F. longipes propolis and 8 were found exclusively in A. mellifera propolis. The chemical profiles of the propolis extracts were determined by atmospheric pressure chemical ionization-mass spectrometry and liquid chromatography-electrospray ionization-tandem mass spectrometry allowed to identify several prenylated benzophenones. A. mellifera extracts exhibited major antioxidant activity as assessed by the 2,2-diphenyl-1picrylhydrazyl method and all extracts exhibited antioxidant activity as assessed by the β-carotene/linoleic acid method. The ethanolic extracts of the propolis showed promisor activity against all tested microorganisms.

Rationale: Propolis has a great diversity in its composition due to numerous factors; therefore, each study is an important contribution to the knoFwledge of its composition and biological action. The objective of this study was to determine the chemical profile and biological activity of propolis produced by Scaptotrigona depilis.Methods: Extracts with 70% ethanol (EPE70) and with cereal alcohol (CAPE) were elaborated, and then characterized using UHPLC-ESI(+)-MS/MS. Volatile compounds were extracted and then characterized using gas chromatography mass spectrometry (GC-MS). In addition, antimicrobial activities were verified against resistant strains. Results:The volatile compounds of propolis predominantly consist of sesquiterpenes. Using the exploratory metabolomic approach, compounds of different classes were putatively identified in the ethanolic extracts, of which the most representative were terpenes, and some of the sesquiterpenes identified among the volatiles were also detected. The extracts were shown to be active against Escherichia coli and Staphylococcus aureus bacteria with a minimum inhibitory concentration (MIC) of 0.5 and 1.0 mg mL À1 , respectively. Conclusions:The molecular network approach proved to be determining the chemical profile of S. depilis propolis rapidly and accurately, and led to the identification of lipophilic compounds. The identification of compounds using GC-MS and UHPLC-ESI(+)-MS/MS is complementary and useful for the characterization of propolis.

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Rationale Annona species are of interest for the isolation of bioactive molecules; however, studies of Annona jahnii Saff. are limited. The exploration of bioactive metabolites of endophytes isolated from this species is unprecedented and allows the preservation of the host plant, in addition to enabling the discovery of compounds with promising biological activities. Methods Ethyl acetate extracts from the cultured media of five fungi were obtained. The antioxidant capacity of the extracts was measured using the 1,1‐diphenyl‐2‐picrylhydrazyl free radical method. Antimicrobial activity was determined using the microdilution method in broth in 96‐well plates. The exploration of the metabolic profile of the extracts and dereplication of the compounds were performed using ultra‐high‐performance liquid chromatography/electrospray ionization/tandem mass spectrometry (UHPLC/ESI‐MS/MS) combined with analysis using molecular networking (MN). Results A total of 1818 MS features were detected in the five selected extracts, of which 39 compounds were putatively identified. The secondary metabolites with the highest abundance were alkaloids, naphthopyrons, and cytochalasins. Other secondary metabolites include fumonisins, coumarin, and a meroterpenoid. Most of these compounds are related to specific biological properties such as antioxidant, anti‐inflammatory, antimicrobial, antiviral, and antitumor activities. Extracts F398 and F403 showed inhibitory activity of the four pathogens tested. Extracts F475 and F506 did not inhibit the growth of Staphylococcus aureus, and F407 did not inhibit the growth of Escherichia coli in addition to having potent antioxidant activity, with IC50 values of 10 μg/mL or less. Conclusions The use of UHPLC/ESI‐MS/MS data combined with MN proved useful in the dereplication of bioactive molecules of complex extracts that are still unexplored. These initial investigations should significantly assist in further research and increase the efficiency and speed in the discovery of new sources of secondary metabolites and new natural products.

Este trabalho apresenta o relato de experiência do curso “O biocombustível da biodiversidade”. Foram selecionados 20 alunos da Escola Estadual Ana Libória, com o objetivo de apresentar o potencial energético da biodiversidade que os cerca. O curso foi executado em várias etapas: abordagem do tema, conceitos referentes à química e óleos vegetais, normas de segurança em laboratório, vidrarias e suas funções seguida de uma sequência de atividades práticas correlatas, como: coletas de material, métodos de extração de óleos vegetais, métodos cromatográficos e reacionais. O curso proporcionou a integração dos alunos com o ambiente de pesquisa na Universidade Federal de Roraima - UFRR e a vivência na prática dos conceitos e teorias.

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