Acetylenic fatty acids from Porcelia macrocarpa (Annonaceae) against trypomastigotes of Trypanosoma cruzi: Effect of octadec-9-ynoic acid in plasma membrane electric potential.

Porcelia macrocarpa (Warm.) R. E. Fries (Annonaceae) is an endemic plant in Brazil where its tasty pulp has been eaten fresh. The hexane extract from its flowers was subjected to chromatographic procedures to afford four acetylene derivatives identified as octadec-9-ynoic (stearolic acid - 1), (11E)-octadec-11-en-9-ynoic (santalbic acid - 2), 8-hydroxyoctadec-9,11-diynoic (3) and 8-hydroxyoctadec-17-en-9,11-diynoic (isanolic acid - 4) acids by NMR and HRESIMS. Among tested compounds against trypomastigote forms of T. cruzi, octadec-9-ynoic acid (1) displayed higher potential with IC50 = 27.6 µM and a selectivity index (SI) higher than 7. Compounds 2 and 3 showed IC50 of approximately 60 µM while compound 4 was inactive. The lethal action of the compound 1 was investigated using spectrofluorometric techniques to detect ROS content, plasma membrane permeability and plasma membrane potential by flow cytometry. Compound 1 showed no alteration in the production of ROS of treated trypomastigotes and no alteration of the plasma membrane permeability was observed as detected by the fluorescent probe SYTOX-green after 120 min of incubation. However, by using the potential-sensitive fluorescent probe DiSBAC2(3), compound 1 caused depolarization of the plasma membrane potential when compared to untreated parasites. Our results demonstrated the anti-T. cruzi effects of compounds 1-3 isolated from flowers of P. macrocarpa and indicated that the lethal effect of compound 1 in T. cruzi could be associated to the plasma membrane disturbance of the parasite.

Antifungal compounds produced by Colletotrichum gloeosporioides, an endophytic fungus from Michelia champaca.

In this study, eight endophytic fungi were isolated from the leaves, stems and roots of Michelia champaca. The isolates were screened and evaluated for their antifungal, anticancer and acetylcholinesterase (AChE) inhibitory activities. All of the extracts exhibited potent activity against two evaluated phytopathogenic fungi. Chemical investigation of EtOAc extracts of the endophytic fungus Colletotrichum gloeosporioides resulted in the isolation of one new compound, 2-phenylethyl 1H-indol-3-yl-acetate (1), and seven known compounds: uracil (2), cyclo-(S*-Pro-S*-Tyr) (3), cyclo-(S*-Pro-S*-Val) (4), 2(2-aminophenyl)acetic acid (5), 2(4-hydroxyphenyl)acetic acid (6), 4-hydroxy- benzamide (7) and 2(2-hydroxyphenyl)acetic acid (8). All of the compound structures were elucidated using 1D and 2D NMR and MS analyses. The antifungal and AChE inhibitory activities of compounds 1-8 were evaluated in vitro. Compound 1 exhibited promising activity against Cladosporium cladosporioides and C. sphaerospermum that was comparable to that of the positive control nystatin.

Bioactive secondary metabolites from Phomopsis sp., an endophytic fungus from Senna spectabilis.

Chemical investigation of an acetonitrile fraction from the endophytic fungus Phomopsis sp. led to the isolation of the new natural product 2-hydroxy-alternariol (7) together with the known compounds cytochalasins J (1) and H (2), 5'-epialtenuene (3) and the mycotoxins alternariol monomethyl ether (AME, 4), alternariol (AOH, 5) and cytosporone C (6). The structure of the new compound was elucidated by using 1-D and 2-D NMR (nuclear magnetic resonance) and high resolution mass spectrometry. The cytochalasins J (1) and H (2) and AOH (5) exhibited potent inhibition of the total ROS (reactive oxygen species) produced by stimulated human neutrophils and acted as potent potential anti-inflammatory agents. Moreover, cytochalasin H (2) demonstrated antifungal and acetylcholinesterase enzyme (AChE) inhibition in vitro.

Chemical profile and biological potential of non-polar fractions from Centroceras clavulatum (C. Agardh) Montagne (Ceramiales, Rhodophyta).

The present study reports the Gas Chromatography-Mass Spectrometry (GC-MS) evaluation of the hexanes and dichloromethane fractions from extracts of the red alga Centroceras clavulatum (C. Agardh) Montagne. Twenty three compounds were identified, totaling ca. 42% of both fractions (0.18 g mass extract). The main constituents of the fractions were hexadecanoic acid (17.6%) and pentadecanoic acid (15.9%). Several secondary metabolites with interesting biological activity, such as (-)-loliolide, neophytadiene, phytol were identified. In addition, several classes of secondary metabolites, including phenolic compounds (e.g., phenylacetic acid), terpene derivatives, fatty acids, halogenated compound (e.g., 2-chlorocyclohexenol), lignoids, steroids, esters, amides (e.g., hexadecanamide), ketones, carboxylic acids, aldehydes and alcohols were observed. The occurrence of several of these structural classes is described for the first time in this species. The same fractions analyzed by GC-MS, and a separate set of polar fractions, were evaluated against two life cycle stages (epimastigote and trypomastigote forms) of the protozoan Trypanosoma cruzi and against phytopatogenic fungi Cladosporium cladosporiodes and C. sphaerospermum. The dichloromethane fraction was active against both T. cruzi forms (epimastigote IC(50) = 19.1 µg.mL-1 and trypomastigote IC(50) = 76.2 µg.mL-1). The hexanes and ethyl acetate fractions also displayed activity against both fungi species (200 µg) by TLC-bioautography.

A new isoflavone glucoside and other compounds from Poiretia bahiana C. Mueller: Chemophenetics, fragmentation pattern and biogenetic implications.

The genus Poiretia belongs to the Fabaceae (Leguminosae) family and it encompasses twelve species of flowering plants. The chemistry of this genus is scarcely investigated, although some studies have demonstrated the potential of Poiretia species to produce important bioactive compounds. Herein, we describe the phytochemical investigation of P. bahiana C. Mueller leaves. A new isoflavone glucoside named as 2',4',5'-trimethoxyisoflavone-7-O-ß-D-glucopyranoside (1), along with six known isoflavones (2-7), two rotenones (8-9), cyclitol 3-O-methyl-chiro-inositol (10), the amino acid proline (11), a mixture of sitosterol (12) and stigmasterol (13), and a mixture of the triterpenes lupeol (14) and ß-amirine (15) were obtained from P. bahiana leaves. The structures were established by extensive analysis of their spectroscopic data, which included 1H NMR, 13C NMR, DEPT, and 2D-NMR (13C1H HETCOR and 13C1H COLOC). Two isoflavones (3 and 5) and two rotenones (8-9) exhibited antifungal activity against the plant pathogenic fungus Cladosporium sphaerospermum. Furthermore, the biogenetic implications of the oxygenation pattern of the B-ring of the isoflavones, and the chemophenetics and fragmentation pattern of the isoflavones and rotenones are discussed.

Anti-inflammatory activity of essential oil from leaves of Myrciaria tenella and Calycorectes sellowianus.

The GC-MS analysis revealed that the leaf essential oils of Myrciaria tenella (DC.) Berg and Calycorectes sellowianus O. Berg (Myrtaceae) were composed of 34 and 37 compounds, respectively. The main constituents of M. tenella oil were beta-caryophyllene (25.1%), and spathulenol (9.7%), while for C. sellowianus were guaiol (13.1%) and beta-caryophyllene (8.6%). The anti-inflammatory effect of both essential oils was investigated in vitro and in vivo. Both oils reduced significantly (p < 0.005) the treated neutrophils chemotaxis with 93% and 91% inhibition for M. tenella and C. sellowianus, respectively. However, in the systemic treatment with the essential oils (50 mg/kg p.o.) only the M. tenella oil was able to significantly reduce the carrageenan-induced paw edema with a similar effect to that observed for indomethacin (10 mg/kg), the positive control.

Chemical Composition and Antimicrobial Properties of Piper ovatum Vahl.

The chemical composition of the essential oil obtained from the leaves of Piperovatum Vahl by hydrodistillation was analyzed by GC-MS. The main constituents found were delta-amorphene (16.5 %), cis-muurola-4(14),5-diene (14.29 %) and gamma-muurolene(13.26%). The crude extracts and isolated compounds were screened for their antimicrobial activity. Hydroalcoholic extracts of different parts of Piper ovatum Vahl, essential oil andamides isolated from leaves were tested against Gram-positive and Gram-negative bacteria and Candida species. All extracts and amides were active against Bacillus subtilis andCandida tropicalis, including clinical strains. Essential oil was active against C. tropicalis.These amides showed an inhibitory effect on the adherence of C. tropicalis ATCC 28707 on cover glasses at 10 microg/mL, but did not show morphological alterations at the tested concentrations. Amides were identified as piperovatine and piperlonguminine, and showed MIC values of 15.6 and 31.2 microg/mL to B. subtilis and 3.9 microg/mL to C. tropicalis, and low toxic effects to Vero cells and macrophages.

Chemical Composition, Antimicrobial and Antioxidant Activities of Essential Oils from Two Avicennia schaueriana Stapf & Leechm. Ex Moldenke (Acanthaceae) Populations.

BACKGROUND: Avicennia schaueriana Stapf & Leechm. ex Moldenke (Acanthaceae) is a native species from the Brazilian mangroves presenting ecological and economic significance. This study compared the composition and the biological activities from the essential oils obtained from two A. schaueriana populations collected at Jureia-Itatins and Ilha do Cardoso. METHODS: Essential oils were obtained by conventional means, and their compositions were analyzed by GC-MS. Screening assays for antimicrobial activity were carried out by the microdilution method and the antioxidant potential was assessed by the DPPH scavenging method. RESULTS: The GC-MS analysis indicated that the Jureia oil (1) was composed mostly of the fatty acids palmitic (46.5%) and myristic (11.6%) acids, while the main components for the Ilha do Cardoso oil (2) were eugenol (19.7%), eugenol acetate (12.9%) and palmitic acid (15.1%). The oils showed an IC50 of 0.9 ± 0.011 mg/mL for 1 and 1.13 ± 0.028 mg/mL for 2 in the DPPH assay. The antimicrobial assay indicated MIC > 217 µg/mL for all tested microorganisms. CONCLUSIONS: The different essential oil composition may indicate the presence of chemotypes for A. schaueriana. The antioxidant activity of the oils was weak if compared with flavonoids. Despite the high MIC values, these oils presented some antibacterial potential against Pseudomonas aeruginosa.

Chemical Composition, Antifungal and Antioxidant Activities of Hedyosmum brasiliense Mart. ex Miq. (Chloranthaceae) Essential Oils.

Background: Hedyosmum brasiliense Mart. ex Miq. (Chloranthaceae) is a dioecious shrub popularly used in Brazil to treat foot fungi and rheumatism. This work investigated the chemical composition, antifungal, and antioxidant activities of flowers and leaves of H. brasiliense essential oils; Methods: H. brasiliense male and female flowers and leaves were collected at Ilha do Cardoso (São Paulo) and the essential oils were extracted by hydrodistillation and analyzed by GC/MS and their similarity compared by Principal Component Analysis. Antifungal activity was performed by bioautography and antioxidant potential by 2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH) free radical scavenging and ß-carotene/linoleic acid system; Results: The major compounds for all oils were sabinene, curzerene, and carotol, but some differences in their chemical composition were discriminated by Principal Component Analysis (PCA) analysis. Bioautography showed two antifungal bands at Rf's 0.67 and 0.12 in all samples, the first one was identified as curzerene. The oils presented stronger antioxidant potential in ß-carotene/linoleic acid bioassay, with IC50's from 80 to 180 µg/mL, than in DPPH assay, with IC50's from 2516.18 to 3783.49 µg/mL; Conclusions: These results suggested that curzerene might be responsible for the antifungal activity of H. brasiliense essential oils. Besides, these essential oils exhibited potential to prevent lipoperoxidation, but they have a weak radical scavenger activity.

Chromenes from Peperomia serpens (Sw.) Loudon (Piperaceae).

Chromatographic separation of the CH2Cl2 extract from leaves of Peperomia serpens yielded two chromenes [5-hydroxy-8-(3',7'-dimethylocta-2',6'-dienyl)-2,2,7-trimethyl-2H-1-chromene (1) and 5-hydroxy-8-(3'-methyl-2'-butenyl)-2,2,7-trimethyl-2H-1-chromene-6-carboxylic acid (2)], besides the known chromene [methyl 5-hydroxy-2,2,7-trimethyl-2H-1-chromene-6-carboxylate (3)] and the flavonoid, dihydrooroxylin (4). Their structural elucidation were achieved by spectroscopic analyses. The antifungal activities of the CH2Cl2 extract and the isolated chromenes were measured bioautographically against Cladosporium cladosporioides and C. sphaerospermum, when it was found that the crude extract showed higher activity as compared to the pure compounds.

Antifungal flavanones and prenylated hydroquinones from Piper crassinervium Kunth.

Bioactivity-guided fractionation of the EtOAc extract from leaves of Piper crassinervium yielded three prenylated hydroquinones together with two known flavanones naringenin and sakuranetin. Their structures were determined by means of spectroscopic analysis (NMR, IR, UV and MS) including two-dimensional NMR spectroscopy experiments (1H-1H COSY, HMQC, HMBC and NOESY). The antifungal activity was determined by direct bioautography against Cladosporium cladosporioides and C. sphaerospermum.

Antifungal amides from Piper arboreum and Piper tuberculatum.

In continuation of our study of the Piperaceae we have isolated several amides, mainly those bearing isobutyl, pyrrolidine, dihydropyridone and piperidine moieties. Bioactivity-guided fractionation of extracts from leaves of Piper arboreum yielded two new amides, N-[10-(13,14-methylenedioxyphenyl)-7(E),9(Z)-pentadienoyl]-pyrrolidine (1), arboreumine (2) together with the known compounds N-[10-(13,14-methylenedioxyphenyl)-7(E)-pentaenoyl]-pyrrolidine (3) and N-[10-(13,14-methylenedioxyphenyl)-7(E),9(E)-pentadienoyl]-pyrrolidine (4). Catalytic hydrogenation of 3 yielded the amide N-[10-(13,14-methylenedioxyphenyl)-pentanoyl]-pyrrolidine (5). We also have isolated six amides (6-11) and two antifungal cinnamoyl derivatives (12, 13) from seeds and leaves of Piper tuberculatum. Compounds 1-11 showed antifungal activity as determined by direct bioautography against Cladosporium sphaerospermum while compounds 3-4 and 6-13 also showed antifungal activity against C. cladosporioides.

Chemical composition and biological properties of Ipomoea procumbens

ABSTRACT Natural products have been the most valuable source of chemical compounds in the discovery of novel medicines. Secondary metabolites from terrestrial and marine organisms have found considerable use in the treatment of numerous diseases and have been considered lead molecules both in their natural form and as templates for medicinal chemistry. Brazil has an exceptionally rich biodiversity, and a valuable source of secondary metabolites that can be useful for the development of bioproducts. Ipomoea species, Convolvulaceae, are mostly found in tropical and sub-tropical regions, including South America and many are used for nutritional and medicinal purposes. Ipomoea procumbens Mart. & Choisy is endemic from South America, and this is the first study reported on the chemical composition and biological activities of this species. The present work reports the tentatively identification of natural products present in the extracts using a high performance liquid chromatography-high resolution mass spectrometry method. Additionally, the antioxidant and antifungal biological activities of the leaves, roots and steams extracts and fractions of this species were evaluated. While for the antioxidant activity the hydromethanol fractions (leaves, stem and roots) were more active, the methanol fractions of leaves and stem provided better results for the antifungal assay.

A new minor dimmeric ester from seeds of Cassia fistula L. (Leguminosae).

Bioactivity-guided fractionation of n-hexane phase from MeOH extract of the seeds of Cassia fistula L. (Leguminosae) yielded two bioactive substances against Cladosporium cladosporioides and C. sphaerospermum. After spectroscopic analysis, these compounds were characterised as the known benzyl 2-hydroxy-3,6-dimethoxybenzoate and its dimer dibenzyl 2,2'-dihydroxy-3,6,3″,6″-tetramethoxy-biphenyl-1,1'-dicarboxylate, which showed a new structural arrangement.

Secondary metabolites isolated from Piper chimonantifolium and their antifungal activity.

In this study, the CH(2)Cl(2) extract from leaves of Piper chimonantifolium was subjected to several chromatographic separation procedures to afford one chromene (gaudichaudianic acid) as a major compound as well as two flavonoids (dihydrooroxylin and pinocembrin) and three steroids (sitosterol, sitosteryl palmitate and stigmasterol). The structures of all determined compounds were characterised by spectrometric analysis, mainly mass spectrometry and NMR, as well as their optical properties. This article describes the first phytochemical study of the leaves of P. chimonantifolium and an evaluation of the antifungal activity of its major compounds.

Isoswertisin flavones and other constituents from Peperomia obtusifolia.

A phytochemical investigation of the leaves and stems of Peperomia obtusifolia (Piperaceae) yielded a new flavone C-diglycoside isoswertisin-4'-methyl-ether-2''α-L-rhamnoside (1), along with four known compounds: isoswertisin-2''α-L-rhamnoside (2), (+)-diayangambin (3), 2-episesalatin (4) and corchoionoside C (5). The structures of the two flavone C-diglycosides (1, 2) were elucidated on the basis of 1D and 2D NMR spectroscopy and MS spectrometric data. These flavones were evaluated by bioautographic assay against Cladosporium cladosporioides and C. sphaerospermum and showed weak antifungal activity.

Evaluation of acetylcholinesterase inhibitory activity of Brazilian red macroalgae organic extracts

Abstract Alzheimer's disease affects nearly 36.5 million people worldwide, and acetylcholinesterase inhibition is currently considered the main therapeutic strategy against it. Seaweed biodiversity in Brazil represents one of the most important sources of biologically active compounds for applications in phytotherapy. Accordingly, this study aimed to carry out a quantitative and qualitative assessment of Hypnea musciformis (Wulfen) J.V. Lamouroux, Ochtodes secundiramea (Montagne) M.A. Howe, and Pterocladiella capillacea (S.G. Gmelin) Santelices & Hommersand (Rhodophyta) in order to determine the AChE effects from their extracts. As a matter of fact, the O. secundiramea extract showed 48% acetylcholinesterase inhibition at 400 μg/ml. The chemical composition of the bioactive fraction was determined by gas chromatography–mass spectrometry (GC–MS); this fraction is solely composed of halogenated monoterpenes, therefore allowing assignment of acetylcholinesterase inhibition activity to them.

Antibacterial, antifungal and cytotoxic activities exhibited by endophytic fungi from the Brazilian marine red alga Bostrychia tenella (Ceramiales)

Abstract Marine environment is one of the most important sources regarding natural products research. Besides, marine microorganisms have been denominated as a talented natural source for discovery of new leads. Although the association of macroalgae and fungi has been described regarding ecological issues, there is a lack of studies about marine seaweed endophytic fungi. In this context, the goal of this study was to evaluate cytotoxic, antifungal and antibacterial activities of endophytic fungi isolated from the Brazilian marine seaweed Bostrychia tenella (J.V. Lamouroux) J. Agardh (Ceramiales, Rhodophyta). Forty-five endophytic microorganism strains were isolated from B. tenella. Crude extracts and organic fractions of ten selected strains were obtained after growth in rice medium. Samples were evaluated for cytotoxicity, antifungal and antibacterial assays. Penicillium strains showed positive results in a diversity of assays, and other five strains were active in at least one test. In addition, cytochalasin D was isolated from Xylaria sp. This alga is composed of a microbiological potential, since its endophytic strains exhibited remarkable biological properties. Moreover, cytochalasin D isolation has confirmed chemical potential of marine endophytic strains. This is the first study in which cultured fungi isolates from the Brazilian macroalga B. tenella were evaluated concerning biological properties. Results corroborated that this species could be a pharmaceutical source from marine environment. Furthermore, Acremonium implicatum is being firstly described as marine endophyte and Xylaria sp., Trichoderma atroviride and Nigrospora oryzae as marine seaweed endophytes. Thus, this work reports the first study relating detailed isolation, cultivation and biological evaluation (cytotoxic, antifungal and antibacterial) of endophytes Penicillium decaturense and P. waksmanii from the Brazilian marine red alga B. tenella. We are also reporting the isolation of cytochalasin D, a known antitumor and antibiotic compound, from Xylaria sp. strain. Despite widespread prevalence in terrestrial and marine habitats, this present work describes the first occurrence of cytochalasin D as a metabolite from marine seaweed endophyte.

Differential acetyl cholinesterase inhibition by volatile oils from two specimens of Marlierea racemosa (Myrtaceae) collected from different areas of the Atlantic Rain Forest.

The volatile oil composition and anti-acetyl cholinesterase activity were analyzed in two specimens of Marlierea racemosa growing in different areas of the Atlantic Rain Forest (Cananéia and Caraguatatuba, SP, Brazil). Component identifications were performed by GC/MS and their acetyl cholinesterase inhibitory activity was measured through colorimetric analysis. The major constituent in both specimens was spathulenol (25.1% in Cananéia and 31.9% in Caraguatatuba). However, the first one also presented monoterpenes (41.2%), while in the Carguatatuba plants, this class was not detected. The oils from the plants collected in Cananéia were able to inhibit the acetyl cholinesterase activity by up to 75%, but for oils from the other locality the maximal inhibition achieved was 35%. These results suggested that the monoterpenes are more effective in the inhibition of acetyl cholinesterase activity than sesquiterpenes as these compounds are present in higher amounts in the M. racemosa plants collected in Cananéia.

Structure-activity relationship of (-) mammea A/BB derivatives against Leishmania amazonensis.

To study the structure-activity relationship of coumarin (-) mammea A/BB isolated from the CH(2)Cl(2) extract of Calophyllum brasiliense leaves, we evaluated the antileishmanial activity of natural, synthetic and derivatives of this coumarin, against promastigote and intracellular amastigote forms of Leishmania amazonensis, and their cytotoxicity to J774G8 murine macrophages. The derivatives were obtained by hydrogenation and methoxylation reactions. The compound structures were elucidated on the basis of spectroscopic data. The compounds 5,7-dihydroxy-8-(2-methylbutanoyl)-6-(3-methylbutyl)-4-phenyl-chroman-2-one (3), 7-hydroxy-5-methoxy-8-(2-methylbutanoyl)-6-(3-methylbut-2-en-1-yl)-4-phenylcoumarin (4) and 5,7-dimethoxy-8-(1-methoxy-2-methylbutyl)-6-(3-methylbut-2-en-1-yl)-4 phenylcoumarin (6) were more biologically active than the compound (-) mammea A/BB (1) (7.4 microM), with IC(50) values from 0.9, 2.4 and 1.9 microM respectively; compound (3) displayed the highest activity. The compounds mammea B/BB (2), 5,7-dimethoxy-8-(2-methylbutanoyl)-6-(3-methylbut-2-en-1-yl)-4-phenylcoumarin (5) and 5,7-dihydroxy-4-phenylcoumarin (7) were less active than (-) mammea A/BB (1), with IC(50) of 30.1, 15.1 and 60.2 microM respectively; compound (7) showed the lowest antileishmanial activity of all. Compounds (1), (3), (4) and (6) were active not only against promastigote forms of L. amazonensis, but also against intracellular amastigote forms with IC(50) of 14.3, 0.6, 34.0 and 22.2 microM, respectively. Interestingly, compound (3) showed the most antileishmanial activity of all. This study demonstrated that several aspects of the structure were important for antileishmanial activity.