Natural Occurring Phenolic Derivatives from Mauritia flexuosa (Buriti) Stems and Their Potential Antibacterial Activity against Methicillin-Resistant Staphylococcus aureus (MRSA).

Mauritia flexuosa Linnaeus filius (buriti or aguage; Arecaceae) is a palm used by traditional medicine in Brazil to treat dysentery and diarrhea. Our group showed that the soluble dichloromethane (CH2 Cl2 ) fraction from EtOH extract from M. flexuosa stems inhibited the growth of methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) and it is rich in phenolic compounds. This study aimed to isolate new phenolic compounds from CH2 Cl2 fraction from M. flexuosa stems with in vitro antibacterial activity. The crude CH2 Cl2 fraction was fractionated by gel permeation chromatography (GPC) followed by semi-preparative RP-HPLC. The antibacterial activity was evaluated using the broth microdilution method against MSSA (ATCC 29213) and MRSA (clinical isolate 155). All compounds were also tested against Gram-negative (Escherichia coli; ATCC 35218) bacteria and two fungi species (Candida albicans; ATCC 14053 and Trichophyton rubrum; ATCC MYA 4438). The chemical structures of isolated compounds were determined by analysis and comparison with literature data of their NMR and HRMS spectra and optical activity. The chemical investigation yielded seven aromatic compounds, of which four, (2S,15S)-2,15-dimethyl-2,15-dioxa-1,8(1,4)-dibenzenacyclotetradecaphane (1), (2S,5S)-1-(4-hydroxyphenyl)hexane-2,5-diol (3), bruguierol E (4), and buritin (5) were previously unreported and three are known compounds identified as 6-(4'-hydroxyphenyl) hexan-2-one (2), (+)-(2R,3R)-dihydrokaempferol (6), and (+)-(2R)-naringenin (7). Compounds 1 and 7 showed antibacterial activity against MRSA and MSSA with minimum inhibitory concentrations (MICs) of between 62.5 and 31.3 µg/mL, respectively. Our preliminary findings support that CH2 Cl2 fraction from buriti, a typical species of flooded areas of Brazilian savanna, and its aromatic phenolic compounds are active against MSSA and MRSA contributing with understanding about the traditional use of this species.

Bioactive compounds and health benefits of some palm species traditionally used in Africa and the Americas - A review.

ETHNOPHARMACOLOGICAL RELEVANCE: According to previous ethno-medicinal reviews, Cocos nucifera, Elaeis guineensis and Phoenix dactylifera are among the main palms which are often used on the American and African continents to treat infections, infestations and disorders in the digestive, respiratory, genito-urinary, dermal, endocrine, cardiovascular, muscular-skeletal, mental and neural systems, as well as neoplasms, dental issues and metabolic and nutritional disorders. In addition, one or more species of the wild genera Acrocomia, Areca, Astrocaryum, Attalea, Bactris, Borassus, Calamus, Chamaedorea, Chamaerops, Euterpe, Hyphaene, Mauritia, Oenocarpus and Syagrus have a high number of records of these ethno-medicinal uses. The most used parts of the palm tree are the fruits, followed by roots, seeds, leaves and flower sap. AIM OF THE STUDY: This review discusses the phytochemical composition and the pharmacological properties of these important ethno-medicinal palms, aiming to provide a contribution to future research prospects. MATERIALS AND METHODS: Significant information was compiled from an electronic search in widely used international scientific databases (Google Scholar, Science Direct, SciFinder, Web of Science, PubMed, Wiley on line Library, Scielo, ACS Publications), and additional information was obtained from dissertations, theses, books and other relevant websites. RESULTS: Palms, in general, are rich in oils, terpenoids and phenolic compounds. Fruits of many species are notable for their high content of healthy oils and fat-soluble bioactive compounds, mainly terpenoids, such as pigment carotenoids (and provitamin A), phytosterols, triterpene pentacyclics and tocols (and vitamin E), while other species stood out for their phenolic compounds derived from benzoic and cinnamic acids, along with flavan-3-ol, flavone, flavonol, and stilbene compounds or anthocyanin pigments. In addition to fruits, other parts of the plant such as seeds, leaves, palm heart, flowers and roots are also sources of many bioactive compounds. These compounds are linked to the ethno-medicinal use of many palms that improve human health against infections, infestations and disorders of human systems. CONCLUSIONS: Palms have provided bioactive samples that validate their effectiveness in traditional medicine. However, the intensive study of all palm species related to ethno-medicinal use is needed, along with selection of the most appropriate palm accessions, ripe stage of the fruit and /or part of the plant. Furthermore, the complete profiles of all phytochemicals, their effects on animal models and human subjects, and toxicological and clinical trials are suggested, which, added to the incorporation of improved technological processes, should represent a significant advance for the implementation of new opportunities with wide benefits for human health.

Green Extraction of Six Phenolic Compounds from Rattan (Calamoideae faberii) with Deep Eutectic Solvent by Homogenate-Assisted Vacuum-Cavitation Method.

A homogenate-assisted vacuum-cavitation extraction (HVE) method with a "green" solvent (a deep eutectic solvent, DES) was developed to extract phenolic compounds from rattan (Calamoideae faberii). In this study, the optimum molar ratio of choline chloride (ChCl) and ethylene glycol (EG) was 1:3, the optimum volume ratio of ChCl-EG:H2O was 6:4, the solid-liquid ratio of HVE was 1:15, and the extraction time of homogenate and vacuum-cavitation were 2.0 min and 25 min, respectively. Under the optimum parameters of HVE, the extraction yield of total phenolic content with ChCl-EG solution was 6.82 mg/g. The higher total phenolic content was detected in fruit tissues (seeds 81.24 ± 1.55 mg/g, episperm 43.21 ± 0.87 mg/g, and arillus 38.47 ± 0.74 mg/g), followed by in leaves (sheath 19.5 ± 0.38 mg/g and blade 17.81 ± 0.33 mg/g). In addition, the content of specific phenolic compounds in aqueous and DES extracts was determined. Chlorogenic acid was the most abundant phenol in most organs of the rattan plant. Gallic acid was mainly distributed in the arillus; protocatechuic acid was mainly distributed in the arillus, sheath, and blade; protocatechuic aldehyde was mainly distributed in the blade, seed, and sheath; (+)-catechins were mainly distributed in the episperm, seed, and sheath; and epigallocatechin gallate was mainly distributed in the blade. The recovery rates of gallic acid, protocatechuic acid, protocatechuic aldehyde, (+)-catechins, chlorogenic acid, and epigallocatechin gallate were 93.77%, 94.09%, 97.32%, 97.83%, 94.41%, and 92.47%, respectively, by AB-8 resin.

Endemic palm species shed light on habitat shifts and the assembly of the Cerrado and Restinga floras.

Species expansions into new habitats are often associated with physiological adaptations, for instance when rain forest lineages colonize dry habitats. Although such shifts have been documented for the Brazilian savanna (Cerrado), little is known about the biogeographic origin of species occupying an extreme South American habitat type, the coastal dunes (Restinga). We examined the formation of this poorly known, endangered habitat by reconstructing the evolutionary history of two endemic species. Due to the proposed recency and uniqueness of this habitat, we hypothesized that Restinga species of the palm genus Allagoptera to be recently evolved and to present derived morphological characters. To detect habit shifts in absolute time, we used one plastid and nine nuclear genes to reconstruct the phylogenetic and biogeographic history of Allagoptera. We used light microscopy and stable isotope analysis to explore whether morphological adaptations occurred concomitantly with habitat shifts. Phylogenetic relationships were well supported and we found ancestral lineages of Allagoptera to be widely distributed throughout habitats that are currently occupied by extant species. Over the last ca. 7Ma Allagoptera has shifted its preference to increasingly dry habitats. Coincident with the colonization of the Cerrado and Restinga, morphological adaptations also evolved, including subterranean stems that are fire-resistant and long underground stem and root systems that facilitate water access. We did not find differences in metabolic pathway or modifications to pollen morphology when compared to other palm lineages. Assuming that the evolutionary history of Allagoptera is indicative of the habitat in which it occurs, our results infer a recent origin for Cerrado species. Although little is known about the formation of the Restinga habitat, our results also suggest a longer history than currently proposed; with an origin of Restinga habitats dating back to the Late Pliocene.

Atividade antimicrobiana dos frutos de Syagrus oleracea e Mauritia vinifera / Antimicrobial activity of Syagrus oleracea and Mauritia vinifera fruits

As espécies pertencentes à família Palmae são muito interessantes do ponto de vista químico e farmacológico. Neste trabalho, foram estudados os frutos de duas espécies da família Palmae, Syagrus oleracea e Mauritia vinifera. Essas palmeiras foram escolhidas por serem espécies brasileiras, abundantes em nosso país, utilizadas popularmente no tratamento de algumas doenças e ainda pouco estudadas. Foram realizados ensaios farmacológicos para avaliação da atividade antimicrobiana dos extratos dos frutos das duas espécies em estudo. Para o teste de atividade antimicrobiana foram utilizadas cepas de bactérias Gram positivas e Gram negativas. A metodologia empregada foi a de Microdiluição em caldo. Foram testados os extratos etanólicos brutos do epicarpo/mesocarpo de S. oleracea e de M. vinifera, o extrato hexânico das amêndoas de S. oleracea, as partições hexânicas e em acetato de etila do epicarpo/mesocarpo de S. oleracea, do epicarpo/mesocarpo e mesocarpo/endocarpo de M. vinifera, na concentração de 100 mg/ml. Os extratos lipofílicos de S. oleracea apresentaram os melhores resultados para essa espécie. Nos testes realizados com M. vinifera, as partições lipofílicas foram as mais inibitórias para a cepa de S. aureus.

Palmae species are very interesting by the chemical and pharmacological points of view. Two species belonging to this family were chosen to initiate the chemical and pharmacological approach of their fruits: Syagrus oleracea (Martius) Beccari and Mauritia vinifera Martius, known in Brazil as Guariroba and Buriti, respectively. Those palm species can be found in several regions of Brazil, especially at the northeast and southeast of the country. They have been used in folk medicine to treat some diseases, however no toxicological and pharmacological studies have been done so far. For the two studied fruits, the antimicrobial activity tests were carried out by broth microdilution methodology. The objective of this work was to contribute for the pharmacological study of palm species, evaluating the antimicrobial activity of the extracts obtained from the fruits of S. oleracea and M. vinifera. The assays evaluated ethanol extracts of the epicarp/mesocarp of S. oleracea and epicarp/mesocarp of M. vinifera; hexane extract of the endosperm of S. oleracea; hexane and ethyl acetate fractions of the epicarp/mesocarp of S. oleracea, epicarp/mesocarp of M. vinifera and mesocarp/endocarp of M. vinifera. The lipophilic extracts of S. oleracea obtained the best results for the species. For M. vinifera, the lipophilic partitions have shown a high inhibitory percentage for S. aureus.