Abstract In this research, aqueous and ethanolic extracts from Justicia pectoralis Jacq and Croton Jacobinensis Baill were characterized. The UPLC-QTOF-MSE analysis was performed on the extracts identified, predominantly, flavonoids, tannins and acids. The extracts did not indicate toxicity in human epithelial cells. C. jacobinensis presented a concentration of phenolics 60.5% higher than J. pectoralis in all scenarios evaluated and, for both samples, the hydroalcoholic extract at 70% exhibited the best efficiency in the extraction (14501.3 and 32521.5 mg GAE 100 g-1 for J. pectoralis and C. jacobinensis, respectively). The antioxidant activity presented a positive correlation with the concentration of phenolics, being 1.186,1 and 1.507,9 μM of Trolox for J. pectoralis and C. jacobinensis at 70% of ethanol; however, it was not verified statistical difference between the ethanolic solutions (p < 0.05). The antimicrobial activity of J. pectoralis extracts was highlighted once was the most effective against gram-positive bacteria. The results suggest that both J. pectoralis and C. jacobinensis extracts present the potential to be applied as natural additives due to their antioxidant and antimicrobial activity and safety. Thus, it is suggesting the development of studies that could investigate the interaction of these plant extracts with food matrices is required.

RESUMO A diversidade de plantas em todo o mundo, bem como a variação química implica em uma grande quantidade de substâncias bioativas. O uso de extratos de plantas com propriedades biológicas surge como uma alternativa viável e saudável quando comparada a substâncias sintéticas. Neste contexto, objetivou-se esta pesquisa avaliar os extratos aquosos das folhas de Physalis angulata L., nativas e cultivadas, quanto a influência do método de extração na bioacessibilidade de compostos bioativos, atividade antioxidante e atividade antimicrobiana. Os extratos foram obtidos a partir das folhas nativas e cultivadas de P. angulata e três diferentes métodos extrativos, decocção, maceração e assistidos por ultrassom. A análise de variância mostrou diferenças significativas entre os métodos extrativos e o tipo de material vegetal. Os extratos obtidos por decocção apresentaram os maiores teores de compostos fenólicos e maior potencial antioxidante para ambos os métodos analíticos (ABTS e DPPH), diferindo significativamente dos demais métodos extrativos. Os índices de bioacessibilidade de compostos fenólicos dos extratos foram considerados reduzidos após a digestão gastrointestinal simulada, e consequentemente, apresentaram baixo potencial antioxidante. O potencial antimicrobiano dos extratos foi observado frente as bactérias Gram-positivas, Staphylococcus aureus e Listeria monocytogenes.

ABSTRACT Plant diversity around the world, as well as the chemical variation, involves a large amount of bioactive substances. The use of plant extracts with biological properties appears as a viable and healthy alternative when compared to synthetic substances. In this context, the objective of this study was to evaluate the aqueous extracts of native and cultivated leaves of Physalis angulata L., as well as the influence of the extraction method on the bioaccessibility of bioactive compounds, antioxidant activity and antimicrobial activity. The extracts were obtained from the native and cultivated leaves of P. angulata using three different extraction methods: decoction, maceration and an ultrasound-assisted method. The analysis of variance showed significant differences between the extraction methods and the type of plant material. The extracts obtained by decoction showed the highest levels of phenolic compounds and higher antioxidant potential for both analytical methods (ABTS and DPPH), differing significantly from the other extraction methods. The bioaccessibility indices of the phenolic compounds obtained from the extracts were considered reduced after the simulated gastrointestinal digestion, and consequently, showed low antioxidant potential. The antimicrobial potential of the extracts was observed against the Gram-positive bacteria Staphylococcus aureus and Listeria monocytogenes.

RESUMO: Amburana cearensis A. C. Smith (Fabaceae) é uma planta comum na Caatinga cearense, onde é popularmente conhecida como cumaru. Vários compostos têm sido isolados de A. cearensis, incluindo ácido protocatecúico, taninos, cumarina, flavonóides e heterosídeos fenólicos, como por exemplo os amburosídeos A e B. O objetivo desse estudo foi avaliar o potencial antimicrobiano e caracterizar o perfil químico do decocto da casca do caule de A. cearensis, visando a sua possível utilização na conservação de alimentos. A caracterização dos compostos químicos foi realizada pelas análises de RMN uni e bidimensionais de 1H e 13C, e cromatografia líquida acoplada à espectrometria de massa. Foram identificados a cumarina, os amburosídeos A e B, e o ácido (Z)-o-cumárico glicosilado. A atividade antimicrobiana foi realizada pela metodologia de microdiluição em placa sobre Escherichia coli, Salmonella Enteritidis, Pseudomonas aeruginosa, Staphylococcus aureus e Listeria monocytogenes. O decocto mostrou atividade antimicrobiana sobre bactérias Gram-positivas. Antimicrobianos naturais podem oferecer vantagens para a produção de alimentos, inibindo microorganismos patogênicos e melhorando a qualidade higiênico-sanitária.

ABSTRACT: The plant, Amburana cearensis A. C. Smith (Fabaceae), commonly called cumaru, is widespread in the Caatinga cearense, a less known ecosystem in Brazil. A. cearensis is rich in several compounds like protocatechuic acid, tannins, coumarin, flavonoids and phenolic heterosides, such as amburosides A and B, that have been isolated. The aim of this study was to determine the antimicrobial potential and draw the chemical profile of the distinct characteristics of A. cearensis stem bark decoction, for its possible potential as a food conservation agent. The chemical compounds were characterized by one- and two-dimensional 1H and 13C NMR analyses and Liquid Chromatography-Mass Spectrometry (LCMS). The compounds of coumarin, amburosides A and B, and glycosylated (Z)-o-coumaric acid. Using the plaque microdilution technique, the antimicrobial action was tested on Escherichia coli, Salmonella Enteritidis, Pseudomonas aeruginosa, Staphylococcus aureus and Listeria monocytogenes. The decoction demonstrated antimicrobial activity on Gram-positive bacteria. This was encouraging because natural antimicrobials are beneficial for food production, as they can inhibit the pathogenic microorganisms and boost the quality of hygiene and cleanliness.