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Rhizophora extracts have several potential biological activities, and their metabolites can be used in the pharmaceutical industry. Extracts of Rhizophora species obtained from mangroves have shown prospective activity against Staphylococcus aureus. This study aimed to investigate the chemical profile of Rhizophora mangle leaves from fringe, basin, and transition mangrove zones and their bactericidal/bacteriostatic potential against S. aureus. R. mangle leaves were collected monthly in 2018 from litterfall in three different zones of the mangrove of Guaratiba State Reserve: fringe, basin, and transition. Extracts were prepared from the material collected in October and December for LC-HRMS/MS analysis, and dereplication was performed using a molecular library search and the classical molecular networking GNPS platform. The minimum inhibitory concentrations (MICs) of the aqueous extract of R. mangle against S. aureus were determined. No S. aureus growth was observed compared to the control for extracts collected from September to December. Different compounds were annotated in each region, yet a marked presence of phenolic compounds was noted, among them glycosylated flavonoid derivatives of quercetin and kaempferol. The results suggest bactericidal/bacteriostatic activity for extracts of R. mangle leaves collected in 2018 from three mangrove forest zones., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.) more...

Two unusual phorbol esters, namely 20-deoxyphorbol-3,4,12-triacetate-13-phenylacetate ( 1 ) and phorbol-3,4,12,13-tetraacetate-20-phenylacetate ( 2 ) plus ingol-3,8,12-triacetate-7-phenylacetate ( 3 ) were isolated from the latex of Euphorbia umbellata and identified by HRESIMS and 2D NMR. Compound 1 is herein described for the first time. Assignment of the phenylacetyl group at C-7 in compound 3 was suggested by the HMBC and NOESY spectra obtained in pyridine- d 5 . In addition to the latex and its distinct terpenoid fractions, the isolated compounds were tested as latent reversal agents against HIV-1-infected J-Lat cells, with reference to phorbol-12-myristate-13-acetate and ingenol-B. Compound 2 reverted 75-80% the viral latency on the GFP-positive cells, resulting EC 50 3.70 μg/mL (SI 6.7), while 1 induced 34-40% reactivation at the same concentration range (4-20 µg/mL). The ingol derivative 3 was ineffective. Phorbol esters were confirmed as effective constituents in the latex since the fraction containing them was 2.4-fold more active than the lyophilised latex at the lowest concentration assayed. more...

Euterpe oleracea Mart. (Arecaceae) is an endogenous palm tree from the Amazon region. Its seeds correspond to 85% of the fruit's weight, a primary solid residue generated from pulp production, the accumulation of which represents a potential source of pollution and environmental problems. As such, this work aimed to quantify and determine the phytochemical composition of E. oleracea Mart. seeds from purple, white, and BRS-Pará açaí varieties using established analytical methods and also to evaluate it as an eco-friendly corrosion inhibitor. The proanthocyanidin quantification ( n -butanol/hydrochloric acid assay) between varieties was 6.4-22.4 ( w / w )/dry matter. Extract characterization showed that all varieties are composed of B-type procyanidin with a high mean degree of polymerization (mDP ≥ 10) by different analytical methodologies to ensure the results. The purple açaí extract, which presented 22.4% ( w / w ) proanthocyanidins/dry matter, was tested against corrosion of carbon steel AISI 1020 in neutral pH. The crude extract (1.0 g/L) was effective in controlling corrosion on the metal surface for 24 h. Our results demonstrated that the extracts rich in polymeric procyanidins obtained from industrial açaí waste could be used to inhibit carbon steel AISI 1020 in neutral pH as an abundant, inexpensive, and green source of corrosion inhibitor. more...

Three known compounds, 20-deoxyphorbol-5 β -hydroxy-12-tiglate-13-isobutyrate ( 1 ), 20-deoxyphorbol-5 β -hydroxy-12-tiglate-13-phenylacetate ( 2 ), and 4-deoxy-4 β -phorbol-12-tiglate-13-phenylacetate ( 3 ), were reisolated from the latex of Euphorbia umbellata through a bioguided fractionation process to target HIV-1 latency reactivation. The in vitro bioassay using infected T-cell lymphoblasts (J-Lat 10.6), complemented with surface CD4 receptor downregulation assessment, led to isolation of the compounds as a highly active ternary mixture. Effective purification of the individual compounds was achieved by first subjecting a phorbol-enriched fraction (previously prepared from crude latex) to MPLC, followed by semipreparative HPLC and characterization by 1D and 2D NMR spectroscopy and (+)-HRESIMS. Compared with a positive control, the isolated compounds were effective in reactivating 68-75% of the virus latency in the range of 9.7-0.097 μ M for compound 1 , 8.85-0.088 μ M for compound 2 , and 9.1-0.091 μ M for compound 3 , with the latter maintaining steady effectiveness down to a 10 -5 dilution. Accordingly, compound 3 may serve as a promising lead compound for the development of anti-HIV drugs based on latency reactivation therapy. more...

Anomalocalyx uleanus (Pax & K. Hoffm.) Ducke (Euphorbiaceae) is a singular species in the genus and is restricted and exclusive to the Brazilian Amazon. A phytochemical study of A. uleanus leaves was performed, yielding the isolation of five major compounds: catechin/epicatechin, afzelin, quercetin 3- O -α-L-rhamnopyranoside, and astilbin. The phytochemical compositions of the methanolic extracts of leaves, roots, bark, and stem bark were determined using a dereplication approach. Forty-six compounds were annotated from the liquid chromatography-mass spectrometry (LC-MS/MS) data, while four lipids were identified using gas chromatography-mass spectrometry (GC-MS). In total, fifty compounds were detected, and they belonged to the primary metabolism and several classes of natural products such as flavonoids, flavonoids O -glycosides, flavonoids C -glycosides, biflavonoids, procyanidin, triterpene, triterpenes esterified with phenylpropanoids, phenylpropanoid derivatives, flavonolignans, coumarins, quinic acid derivatives, and benzoic acid derivatives. This is the first report on the phytochemical data of the genus Anomalocalyx , and the results of this study will contribute to the chemosystematic knowledge of the Euphorbiaceae family and justify the need for investigation of the pharmacological potential of the species A. uleanus . more...

Background : Pimenta dioica is a native tree of Central America, Southern Mexico, and the Caribbean used in traditional medicine. It grows in wet forests in the Guatemalan departments of Petén and Izabal. Since the plant is not being economically exploited in Guatemala, this study was aimed at determining the composition of the essential oil of P. dioica leaves and fruits and the antibacterial activity of the leaves in order to evaluate its possible use in health products. The essential oils of fruits and leaves are used as rubefacient, anti-inflammatory, carminative, antioxidant, and antiflatulent in different countries. Fruits and leaves of P. dioica from Izabal Department were collected in April 2014 and extracted by hydrodistillation method. The oils were analyzed by gas chromatography coupled with mass spectrometry (GC/MS). Yields of 1.02 ± 0.11% for dried leaves and 1.51 ± 0.26% for fruits were obtained. Eugenol was the main component (65.9-71.4%). The leaf oil showed growth inhibition against two Gram-positive and two Gram-negative bacteria. The authors consider that the tree's leaves can be evaluated as a source of ingredients for antiseptic products, and that it is important to evaluate other types of properties such as anti-inflammatory activity. more...

This is the first report investigating the effects of cultivation, growth under full sunlight (MSL) or shade (MS), and processing (drying, sapeco and roasting) on the composition and antioxidant potential of maté. Samples were roasted (180 °C, 200 °C, 220 °C or 240 °C) for a fixed time (10 min) or roasted (10, 20, 30 or 40 min) at a fixed temperature (200 °C). HPLC/UV/MS analysis and measures of total phenolic content (TPC) and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition and soybean oil oxidation) were used to analyse phytochemicals. There were significant differences (p < 0.05, ANOVA/Tukey) in phenolics between MS and MSL samples following certain processing steps, but Principal Component Analysis (PCA) indicated no distinction between MS and MSL samples, suggesting that light intensity had no effect on phenolics. Caffeine increased significantly (p < 0.05) in MS samples. Temperature was more important than time, since pyrolysis of phenolics was more intense at 240 °C., (Copyright © 2018 Elsevier Ltd. All rights reserved.) more...

A new ellagitannin named cauliflorin (1), seven known hydrolyzable tannins (2-8), and six known phenolics (9-14) were isolated from jabuticaba. Compounds 2-8 had not been previously isolated from M. cauliflora fruits. The jabuticaba fruit was analyzed at four developmental stages for ellagitannins 1, 3, 7, and 8, phenolic acids 11 and 12, anthocyanins, organic acids, and sugars via HPLC-UV-DAD and NMRq. The content of ellagitannins and organic acids declined during fruit development, whereas at full ripeness sugar and anthocyanin levels underwent a sharp increase and were mainly constituted by fructose and cyanidin-3-O-glucose, respectively. Ellagitannins' profile varied considerably among fruit tissues, with pedunculagin (3), castalagin (7), and vescalagin (8) mostly concentrated in jabuticaba seeds, whereas cauliflorin (1) and anthocyanins accumulated in the peels. Changes in jabuticaba's phenolic compound contents were mostly influenced by fruit part (peel, pulp, and seed) rather than by degree of ripeness. more...

Leaf and stem explants of Cleome rosea formed calluses when cultured on MS medium supplemented with different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) or 4-amino-3,5,6-trichloropicolinic acid (PIC). The highest biomass accumulation was obtained in the callus cultures initiated from stem explants on medium supplemented with 0.90 microM 2,4-D. Reddish-pink regions were observed on callus surface after 6-7 months in culture and these pigments were identified as anthocyanins. Anthocyanins production was enhanced by reducing temperature and increasing light irradiation. Pigmented calluses transferred to MS1/2 with a 1:4 ratio NH(4)(+)/NO(3)(-), 70 g L(-1) sucrose and supplementation with 0.90 microM 2,4-D maintained a high biomass accumulation and showed an increase of 150% on anthocyanin production as compared with the initial culture conditions. Qualitative analysis of calluses was performed by high performance liquid chromatography coupled to diode array detector and electrospray ionization mass spectrometry (HPLC-DAD/ESIMS). Eleven anthocyanins were characterized and the majority of them were identified as acylated cyanidins, although two peonidins were also detected. The major peak was composed by two anthocyanins, whose proposed identity were cyanidin 3-(p-coumaroyl) diglucoside-5-glucoside and cyanidin 3-(feruloyl) diglucoside-5-glucoside. more...