Marcos J. Salvador

Alkaloids from the Bark of Guatteria hispida and Their Evaluation as Antioxidant and Antimicrobial Agents

Phytochemical investigation of the bark of Guatteria hispida afforded three new alkaloids, 9-methoxy-O-methylmoschatoline (1), 9-methoxyisomoschatoline (2), and isocerasonine (3), along with 10 known alkaloids, 8-oxopseudopalmatine (4), O-methylmoschatoline (5), lysicamine (6), liriodenine (7), 10-methoxyliriodenine (8), nornuciferine (9), anonaine (10), xylopine (11), coreximine (12), and isocoreximine (13). The major compounds, 2, 6, 12, and 13, showed significant antioxidant capacity in the ORAC(FL) assay. Compounds 5, 6, and 7 were active against S. epidermidis and C. dubliniensis, with MIC values in the range 12.5-100 microg mL(-1).

Isolation and HPLC quantitative analysis of antioxidant flavonoids from Alternanthera tenella Colla.

Abstract Phytochemical analysis of the antioxidant ethanolic extract of Alternanthera tenella Colla led to the isolation of six flavonoids, acacetin 8-C-[α-ʟ-rhamnopyranosyl-(1→2)-β-ᴅ-glucopyranoside] (1), 2″-O-α-ʟ-rhamnopyranosyl-vitexin (2), 2″-O-β-d-glucopyranosyl-vitexin (3), vitexin (4), quercetin (5) and kaempferol (6). All the structures were established by ESIMS and NMR spectroscopic methods. Antioxidant capacity of extract, fractions and isolated compounds was determined using the oxygen radical absorbance capacity (ORAC) assay and extract, fractions and flavonoids isolated showed antioxidant activity in vitro. Moreover, the total soluble phenolic contents of the extract and fractions were measured using the Folin- Ciocalteau reagent and the quantitative analysis of flavone C-glycosides major constituents was performed by HPLC

Trypanocidal and antimicrobial activities of Moquinia kingii

A chloroform crude extract (aerial part) and two compounds, apigenin (1) and cynaropicrin (2), isolated from Moquinia kingii were evaluated against Trypanosoma cruzi trypomastigotes in vitro. Antimicrobial activity was also screened using twenty-two strains including gram-positive and gram-negative bacteria and the yeasts Candida albicans and C. tropicalis. The chloroform crude extract, fractions and isolated compounds from M. kingii were active for both activities. The IC50 values for trypanocidal activity obtained for cynaropicrin and apigenin were 93.5 microg/ml and 181 microg/ml, respectively, while the minimum inhibitory concentrations (MICs) varied from 100 microg/ml to 2500 microg/ml, against the strains of bacteria and yeasts evaluated.

Antiproliferative Activity and Induction of Apoptosis in PC-3 Cells by the Chalcone Cardamonin from Campomanesia adamantium (Myrtaceae) in a Bioactivity-Guided Study

The Myrtaceae family is a common source of medicines used in the treatment of numerous diseases in South America. In Brazil, fruits of the Campomanesia species are widely used to make liqueurs, juices and sweets, whereas leaves are traditionally employed as a medicine for dysentery, stomach problems, diarrhea, cystitis and urethritis. Ethanol extracts of Campomanesia adamantium (Myrtaceae) leaves and fruits were evaluated against prostate cancer cells (PC-3). The compound (2E)-1-(2,4-dihydroxy-6-methoxyphenyl)-3-phenylprop-2-en-1-one, cardamonin) was isolated from ethanol extracts of C. adamantium leaves in a bioactivity-guided study and quantified by UPLC-MS/MS. In vitro studies showed that the isolated chalcone cardamonin inhibited prostate cancer cell proliferation and decreased the expression of NFkB1. Moreover, analysis by flow cytometry showed that this compound induced DNA fragmentation, suggesting an effect on apoptosis induction in the PC-3 cell line.

A New Heptasubstituted (E)-Aurone Glucoside and Other Aromatic Compounds of Gomphrena agrestis with Biological Activity

Abstract A new aurone 1 and two known substances, aurantiamide acetate (2) and tiliroside (3), were isolated from the ethanolic extract of Gomphrena agrestis. The structural determination of 1 was based on spectroscopic and spectrometric data. The substance was defined as (E)-3′- O-β-ᴅ-glucopyranosyl-4,5,6,4′-tetrahydroxy-7,2′-dimethoxyaurone. Biological activity of the ethanolic crude extract and isolated compounds against bacteria, fungi and Leishmania amazonensis amastigotes was evaluated. This appears to be the first report documenting aurone and aurantiamide compounds in the Amaranthaceae family. In the evaluation of biological activity the ethanolic extract of G. agrestis and compounds 1, 2, and 3 were shown to be active mainly against Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa.

Trypanocidal and antifungal activities of p-hydroxyacetophenone derivatives from Calea uniflora (Heliantheae, Asteraceae).

The dichloromethane extract of underground parts of Calea uniflora (Heliantheae, Asteraceae) exhibited trypanocidal and antifungal activities. Four p‐hydroxyacetophenone derivatives were isolated as the main compounds: 2‐senecioyl‐4‐(hydroxyethyl)‐phenol (1), 2‐senecioyl‐4‐(angeloyloxy‐ethyl)‐phenol (2), and two new derivatives, 2‐senecioyl‐4‐(methoxyethyl)‐phenol (3) and 2‐senecioyl‐4‐(pentadecanoyloxyethyl)‐phenol (4). 1 and 4 were active towards Trypanosoma cruzi trypomastigotes, reducing their number by 70 and 71% at 500 μg mL−1, whereas 2 and 3 were inactive. All the compounds tested showed antifungal activity with minimal inhibitory concentration values between 500 and 1000 μg mL−1 against pathogenic Candida spp. and dermatophytes. The isolation, structure elucidation, NMR spectral assignments and bioactivity results of these compounds are reported.

Ethanolic Crude Extract and Flavonoids Isolated from Alternanthera maritima: Neutrophil Chemiluminescence Inhibition and Free Radical Scavenging Activity

Extracts from Alternanthera maritima are used in Brazilian folk medicine for the treatment of infectious and inflammatory diseases. Bioassay-guided fractionation of A. maritima aerial parts yielded an ethanolic crude extract, its butanolic fraction and seven isolated flavonoids (two aglycones, two O-glycosides and three C-glycosides) with antioxidative activity. The ability of these samples to scavenge enzymatically generated free radicals (luminol-horseradish peroxidase-H2O2 reaction) and inhibit reactive oxygen species (ROS) production by opsonized zymosan-stimulated human neutrophils (PMNLs) was evaluated by chemiluminescence methods. In both assays, the butanolic fraction was significantly more active than the ethanolic crude extract, the flavonoid aglycones had high inhibitory activities and the Cglycosylated flavonoids had no significant effect even at the highest concentration tested (50 μmol/L). However, the O-glycosylated flavonoids inhibitory effects on chemiluminescence were strongly dependent on the chemical structure and assay type (cellular or cell-free system). Under the conditions tested, active samples were not toxic to human PMNLs.

Bioactivity of flavonoids isolated from Lychnophora markgravii against Leishmania amazonensis amastigotes.

The bioactivity of the flavonoids pinostrobin (1), pinocembrin (2), tectochrysin (3), galangin 3-methyl ether (4), and tiliroside (5) isolated from Lychnophora markgravii aerial parts was investigated in vitro against amastigote stages of Leishmania amazonensis. The compounds were isolated by several chromatographic techniques and their chemical structures were established by ESI-MS and NMR spectroscopic data. The flavonoids 1 and 3 were the most active compounds; they markedly reduced the viability of Leishmania amastigotes.

Determination of Trace Elements in Alternanthera brasiliana and Pfaffia glabrata by SRTXRF: Application in Environmental Pollution Control

Abstract Aiming at environmental control, we report the use of synchrotron radiation total reflection x‐ray fluorescence (SRTXRF) analysis as a technique for trace elements determination in plants. The analyses were performed in two species (total plant) of Amaranthaceae family: Alternanthera brasiliana from four sites and Pfaffia glabrata from a single site. Some elements, such as P, S, K, Ca, Mn, Fe, Cu, Zn, Sr, and Pb were detected in all samples, and the elements Cl, Ti, Cr, Co, Ni, Br, Rb, Sr, Cd, Sn, Sb, and Ba were detected in some samples. The limit of detection (LOD) varied from 0.315 (Cu) to 121.4 (P) µg g−1.

Antifungal activity of extracts and isolated compounds from Buchenavia tomentosa on Candida albicans and non-albicans

AIMnThis study aimed to evaluate the antifungal activity of Buchenavia tomentosa extract and bioactive compounds on six Candida species.nnnMATERIALS & METHODSnThe antimicrobial activity of extract was evaluated using standard strains and clinical isolates. Cytotoxicity was tested in order to evaluate cell damage caused by the extract. Extract was chemically characterized and the antifungal activity of its compounds was evaluated.nnnRESULTSnExtract showed antifungal activity on Candida species. Candida non-albicans were more susceptible than Candida albicans. Low cytotoxicity for extract was observed. The isolated compounds presented antifungal activity at least against one Candida spp. and all compounds presented antifungal effect on Candida glabrata.nnnCONCLUSIONnExtracts from Buchenavia tomentosa showed promising antifungal activity on Candida species with low cytotoxicity. Gallic acid, corilagin and ellagic acid showed promising inhibitory activity on Candida glabrata.