In vitro Evaluation of the Antileishmanial and Antischistosomal Activities of p-Coumaric Acid Prenylated Derivatives.

We have evaluated eight p-coumaric acid prenylated derivatives in vitro for their antileishmanial activity against Leishmania amazonensis promastigotes and their antischistosomal activity against Schistosoma mansoni adult worms. Compound 7 ((E)-3,4-diprenyl-4-isoprenyloxycinnamic alcohol) was the most active against L. amazonensis (IC50=45.92 µM) and S. mansoni (IC50=64.25 µM). Data indicated that the number of prenyl groups, the presence of hydroxyl at C9, and a single bond between C7 and C8 are important structural features for the antileishmanial activity of p-coumaric acid prenylated derivatives.

Antibacterial, Antiparasitic, and Cytotoxic Activities of Chemical Characterized Essential Oil of Chrysopogon zizanioides Roots.

This study aimed to investigate the chemical composition as well as the antibacterial, antiparasitic, and cytotoxic potentialities of the Brazilian Chrysopogon zizanioides root essential oil (CZ-EO) In addition, CZ-EO cytotoxicity to LLCMK2 adherent epithelial cells was assessed. The major compounds identified in CZ-EO were khusimol (30.0 ± 0.3%), ß-eudesmol (10.8 ± 0.3%), α-muurolene (6.0 ± 0.1%), and patchouli alcohol (5.6 ± 0.2%). CZ-EO displayed optimal antibacterial activity against Prevotella nigrescens, Fusobacterium nucleatum, Prevotella melaninogenica, and Aggregatibacter actinomycetemcomitans, with Minimum Inhibitory Concentration (MIC) values between 22 and 62.5 µg/mL and Minimum Bactericidal Concentration (MBC) values between 22 and 400 µg/mL. CZ-EO was highly active against the L. amazonensis promastigote and amastigote forms (IC50 = 7.20 and 16.21 µg/mL, respectively) and the T. cruzi trypomastigote form (IC50 = 11.2 µg/mL). Moreover, CZ-EO showed moderate cytotoxicity to LLCMK2 cells, with CC50 = 565.4 µg/mL. These results revealed an interesting in vitro selectivity of CZ-EO toward the L. amazonensis promastigote and amastigote forms (Selectivity Index, SI = 78.5 and 34.8, respectively) and the T. cruzi trypomastigote form (SI = 50.5) compared to LLCMK2 cells. These results showed the promising potential of CZ-EO for developing new antimicrobial, antileishmanial, and antitrypanosomal drugs.

Hexane extract from Spiranthera odoratissima A. St.-hil. leaves: chemical composition and its bioactive potential against Candida pathogenic species, Leishmania amazonensis and Xylella fastidiosa.

Spiranthera odoratissima A. St.-Hil. (Rutaceae) has been popularly used against abdominal pain and rheumatism. This study aimed at extracting hexane from S. odoratissima (HE-SO) leaves to identify and quantify its volatile compounds by GC-MS and GC-FID and to evaluate its antifungal, antileishmanial and antibacterial activities in vitro. HE-SO exhibited antileishmanial activity against promastigote forms of Leishmania (Leishmania) amazonensis (IC50 = 38.16 µg/mL) and was moderately active against Xylella fastidiosa (MIC = 100 µg/mL). HE-SO also showed remarkable antifungal potential against six strains of Candida species, i. e., C. albicans, C. glabrata, C. parapsilosis, C. krusei, C. tropicalis and C. orthopsilosis. The lowest MIC values were between 31.25 and 250 µg/mL. Spathulenol (20.2%), τ-cadinol (11.7%), α-cadinol (9.4%), caryophyllene oxide (9.2%) and isoaromadendrene epoxide (8.2%) were the major components identified in HE-SO. Therefore, results showed that HE-SO has promising antileishmanial and antifungal actions.

Trypanocidal Activity of Dysphania ambrosioides, Lippia alba, and Tetradenia riparia Essential Oils against Trypanosoma cruzi.

Despite the current treatments against Chagas Disease (CD), this vector-borne parasitic disease remains a serious public health concern. In this study, we have explored the in vitro and/or in vivo trypanocidal and cytotoxic activities of the essential oils (EOs) obtained from Dysphania ambrosioides (L.) Mosyakin & Clemants (Amaranthaceae) (DA-EO), Lippia alba (Mill.) N.E. Brown (Verbenaceae) (LA-EO), and Tetradenia riparia (Hochst.) Codd (Lamiaceae) (TR-EO) grown in Brazil Southeast. DA-EO was the most active against the trypomastigote and amastigote forms in vitro; the IC50 values were 8.7 and 12.2 µg mL-1 , respectively. The EOs displayed moderate toxicity against LLCMK2 cells, but the DA-EO showed high selectivity index (SI) for trypomastigote (SI=33.2) and amastigote (SI=11.7) forms. Treatment with 20 mg/kg DA-EO, LA-EO, or TR-EO for 20 days by intraperitoneal administration reduced parasitemia by 6.36 %, 4.74 %, and 32.68 % on day 7 and by 12.04 %, 27.96 %, and 65.5 % on day 9. These results indicated that DA-EO, LA-EO, and TR-EO have promising trypanocidal potential in vitro, whereas TR-EO has also potential trypanocidal effects in vivo.

In vitro anti-Trypanosoma cruzi activity enhancement of curcumin by its monoketone tetramethoxy analog diveratralacetone.

Chagas disease is a tropical disease caused by the protozoan parasite Trypanosoma cruzi and currently affects millions of people worldwide. Curcumin (CUR), the major constituent of turmeric spice (dry powder of Curcuma longa L. plant rhizomes and roots), exhibits antiparasitic activity against protozoan parasites in vitro. However, because of its chemical instability, poor cellular uptake and limited bioavailability it is not suitable for clinical use. The objective of this study was to synthesize and evaluate in vitro CUR monoketone analog dibenzalacetone (DBA 1) and its non-phenolic, methoxy (2-4) and chloro (5) derivatives for better stability and bioavailability against T. cruzi. Diveratralacetone, the tetramethoxy DBA (DBA 3), was found to be the CUR analog with most enhanced activity against the amastigote forms of four strains of T. cruzi tested (Brazil, CA-I/72, Sylvio X10/4 and Sylvio X10/7) with 50% inhibitory concentration (IC50) < 10 µM (1.51-9.63 µM) and selectivity index (SI) > 10 (C2C12 non-infected mammalian cells). This was supplemented by time-course assessment of its anti-T. cruzi activity. DBA 1 and its dimethoxy (DBA 2) and hexamethoxy (DBA 4) derivatives were substantially less active. The inactivity of dichloro-DBA (DBA 5) was indicative of the important role played by oxygenated groups such as methoxy in the terminal aromatic rings in the DBA molecule, particularly at para position to form reactive oxygen species essential for anti-T. cruzi activity. Although the DBAs and CUR were toxic to infected mammalian cells in vitro, in a mouse model, both DBA 3 and CUR did not exhibit acute toxicity or mortality. These results justify further optimization and in vivo anti-T. cruzi activity evaluation of the inexpensive diveratralacetone for its potential use in treating Chagas disease, a neglected parasitic disease in economically challenged tropical countries.

Biological properties and chemical composition of essential oil from Nectandra megapotamica (Spreng.) Mez. leaves (Lauraceae).

Nectandra megapotamica is a tree species that naturally occurs in the Atlantic Forest, Brazil. This paper aims to investigate the chemical composition and in vitro antibacterial, antileishmanial and antiproliferative activities of essential oil from N. megapotamica leaves (NM-EO). It displayed high antibacterial activity against Streptococcus mutans, S. sobrinus, Prevotella nigrescens and Bacteroides fragilis. NM-EO also exhibited high antileishmanial activity against promastigote forms of Leishmania amazonensis. Its antiproliferative activity was evaluated against the following cells: GM07429A (normal cell), MCF-7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma) and M059J (human glioblastoma). Its major components, which were determined by GC-FID and GC-MS, were α-bisabolol (13.7%), bicyclogermacrene (10.9%), (E,E)-farnesene (10.6%), Z-caryophyllene (9.5%) and (E)-ß-farnesene (7.0%). These results suggest that N. megapotamica, a Brazilian plant, shows initial evidence of a new and alternative source of substances of medicinal interest.

Electrospray ionization tandem mass spectrometry of monoketone curcuminoids.

RATIONALE: Although monoketone curcuminoids (MKCs) have been largely investigated due to their biological activities, data on the gas-phase fragmentation reactions of protonated MKCs under collision-induced dissociation (CID) conditions are still scarce. Here, we combined electrospray ionization tandem mass spectrometry (ESI-MS/MS) data, multiple-stage mass spectrometry (MSn ), deuterium exchange experiments, accurate-mass data, and thermochemical data estimated by computational chemistry to elucidate and to rationalize the fragmentation pathways of eleven synthetic MKCs. METHODS: The MKCs were synthesized by Claisen-Schmidt condensation under basic (1-9) or acidic (10-11) conditions. ESI-CID-MS/MS analyses and deuterium-exchange experiments were carried out on a triple quadrupole mass spectrometer. MSn analyses on an ion trap mass spectrometer helped to elucidate the fragmentation pathways. Accurate-mass data and thermochemical data, obtained at the B3LYP/6-31+G(d,p) level of theory, were used to support the ion structures. RESULTS: The most intense product ions were the benzyl ions ([C7 H2 R1 R2 R3 R4 R5 ]+ ) and the acylium ions ([M + H - C8 H3 R1 R2 R3 R4 R5 ]+ ), which originated directly from the precursor ion as a result of two competitive hydrogen rearrangements. Product ions [M + H - H2 O]+ and [M + H - C6 HR1 R2 R3 R4 R5 ]+ , which are formed after Nazarov cyclization, were also common to all the analyzed compounds. In addition, •Br and •Cl eliminations were diagnostic for the presence of these halogen atoms at the aromatic ring, whereas •CH3 eliminations were useful to identify the methyl and methoxy groups attached to this same ring. Nazarov cyclization in the gas phase occurred for all the investigated MKCs and did not depend on the presence of the hydroxyl group at the aromatic ring. However, the presence and the position of a hydroxyl group at the aromatic rings played a key role in the Nazarov cyclization mechanism. CONCLUSIONS: Our results reinforce some aspects of the fragmentation pathways previously published for 1,5-bis-(2-methoxyphenyl)-1,4-pentadien-3-one and 1,5-bis-(2-hydroxyphenyl)-1,4-pentadien-3-one. The alternative fragmentation mechanism proposed herein can explain the fragmentation of a wider diversity of monoketone curcuminoids.

Geraniol and linalool anticandidal activity, genotoxic potential and embryotoxic effect on zebrafish.

AIM: Geraniol and linalool are major constituents of the essential oils of medicinal plants. MATERIALS & METHODS: Antifungal activity of geraniol and linalool were evaluated against five Candida species. The genotoxicity of these compounds was evaluated by the cytokinesis-block micronucleus test, and the embryotoxic assays use zebrafish model. RESULTS: Geraniol and linalool inhibited Candida growth, but geraniol was more effective. The geraniol at concentration of 800 µg/ml and the linalool at concentration of 125 µg/ml significantly increased chromosome damage. Geraniol was more toxic to zebrafish embryo than linalool: LC50 values were 31.3 and 193.3 µg/ml, respectively. CONCLUSION: Geraniol and linalool have anticandidal activity, but they also exert genotoxic and embryotoxic effects at the highest tested concentrations.

Antimicrobial Activity of Monoketone Curcuminoids Against Cariogenic Bacteria.

We evaluated the antimicrobial activity of 25 monoketone curcuminoids (MKCs) against a representative panel of cariogenic bacteria in terms of their minimum inhibitory concentration (MIC) values. Curcumin A (10) displayed promising activity against Streptococcus mutans (MIC = 50 µg/ml) and Streptococcus mitis (MIC = 50 µg/ml) as well as moderate activity against S. sanguinis (MIC = 100 µg/ml), Lactobacillus casei (MIC = 100 µg/ml), and Streptococcus salivarius (MIC = 200 µg/ml). Results indicated higher activity of compound 10 than that of its bis-ß-diketone analog. Additionally, compounds 3a (1,5-bis(4-methylphenyl)pentan-3-one) and 7b (1,5-bis(4-bromophenyl)pentan-3-ol) were moderately active against S. mitis (MIC = 100 µg/ml) and S. salivarus (MIC = 200 µg/ml).

Fragmentation of 2-aroylbenzofuran derivatives by electrospray ionization tandem mass spectrometry.

We investigated the gas-phase fragmentation reactions of a series of 2-aroylbenzofuran derivatives by electrospray ionization tandem mass spectrometry (ESI-MS/MS). The most intense fragment ions were the acylium ions m/z 105 and [M+H-C6 H6 ]+ , which originated directly from the precursor ion as a result of 2 competitive hydrogen rearrangements. Eliminations of CO and CO2 from [M+H-C6 H6 ]+ were also common fragmentation processes to all the analyzed compounds. In addition, eliminations of the radicals •Br and •Cl were diagnostic for halogen atoms at aromatic ring A, whereas eliminations of •CH3 and CH2 O were useful to identify the methoxyl group attached to this same ring. We used thermochemical data, obtained at the B3LYP/6-31+G(d) level of theory, to rationalize the fragmentation pathways and to elucidate the formation of E, which involved simultaneous elimination of 2 CO molecules from B.

Chemical Composition, Antibacterial, Schistosomicidal, and Cytotoxic Activities of the Essential Oil of Dysphania ambrosioides (L.) Mosyakin & Clemants (Chenopodiaceae).

We have investigated the chemical composition and the antibacterial activity of the essential oil of Dysphania ambrosioides (L.) Mosyakin & Clemants (Chenopodiaceae) (DA-EO) against a representative panel of cariogenic bacteria. We have also assessed the in vitro schistosomicidal effects of DA-EO on Schistosoma mansoni and its cytotoxicity to GM07492-A cells in vitro. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS) revealed that the monoterpenes cis-piperitone oxide (35.2%), p-cymene (14.5%), isoascaridole (14.1%), and α-terpinene (11.6%) were identified by as the major constituents of DA-EO. DA-EO displayed weak activity against Streptococcus sobrinus and Enterococcus faecalis (minimum inhibitory concentration (MIC) = 1000 µg/ml). On the other hand, DA-EO at 25 and 12.5 µg/ml presented remarkable schistosomicidal action in vitro and killed 100% of adult worm pairs within 24 and 72 h, respectively. The LC50 values of DA-EO were 6.50 ± 0.38, 3.66 ± 1.06, and 3.65 ± 0.76 µg/ml at 24, 48, and 72 h, respectively. However, DA-EO at concentrations higher than 312.5 µg/ml significantly reduced the viability of GM07492-A cells (IC50  = 207.1 ± 4.4 µg/ml). The selectivity index showed that DA-EO was 31.8 times more toxic to the adult S. mansoni worms than GM07492-A cells. Taken together, these results demonstrate the promising schistosomicidal potential of the essential oil of Dysphania ambrosioides.

Schistosomicidal Effects of the Essential Oils of Citrus limonia and Citrus reticulata Against Schistosoma mansoni.

We report the in vitro schistosomicidal effects of the essential oil obtained from Citrus limonia leaves (CL-EO) and C. reticulata fruit peels (CR-EO), cultivated in Brazil, against Schistosoma mansoni worms. Limonene (29.9%), ß-pinene (12.0%), sabinene (9.0%), citronellal (9.0%), and citronellol (5.8%) are the major constituents of CL-EO; limonene (26.5%), γ-terpinene (17.2%), linalool (11.1%), octanal (8.0%), myrcene (6.2%), and capraldehyde (3.9%) predominate in CR-EO. CL-EO displayed moderate lethal concentration 50% (LC50 ) of 81.7 and 38.9 µg/ml against male and female worms at 24 and 72 h, respectively. At concentrations of 25 and 100 µg/ml, CL-EO separated between 50 and 75% of the coupled worm pairs during the evaluated period. CR-EO presented moderate LC50 of 81.7 µg/ml against male and female worms at 24 and 72 h. However, this oil separated coupled worm pairs more effectively than CL-EO and displayed lower cytotoxicity to GM07492-A cells (IC50 = 987.7 ± 88.9 µg/ml) as compared to CL-EO (IC50 = 187.8 ± 2.9 µg/ml). The enantiomers (+)-(R)-limonene and (-)-(S)-limonene did not affect S. mansoni adult worm pairs significantly. Taken together, these data indicate that CL-EO and CR-EO exhibit moderate in vitro schistosomicidal activity against adult S. mansoni worms.

Geographic comparison of plant genera used in frugivory among the pitheciids Cacajao, Callicebus, Chiropotes, and Pithecia.

Pitheciids are known for their frugivorous diets, but there has been no broad-scale comparison of fruit genera used by these primates that range across five geographic regions in South America. We compiled 31 fruit lists from data collected from 18 species (three Cacajao, six Callicebus, five Chiropotes, and four Pithecia) at 26 study sites in six countries. Together, these lists contained 455 plant genera from 96 families. We predicted that 1) closely related Chiropotes and Cacajao would demonstrate the greatest similarity in fruit lists; 2) pitheciids living in closer geographic proximity would have greater similarities in fruit lists; and 3) fruit genus richness would be lower in lists from forest fragments than continuous forests. Fruit genus richness was greatest for the composite Chiropotes list, even though Pithecia had the greatest overall sampling effort. We also found that the Callicebus composite fruit list had lower similarity scores in comparison with the composite food lists of the other three genera (both within and between geographic areas). Chiropotes and Pithecia showed strongest similarities in fruit lists, followed by sister taxa Chiropotes and Cacajao. Overall, pitheciids in closer proximity had more similarities in their fruit list, and this pattern was evident in the fruit lists for both Callicebus and Chiropotes. There was no difference in the number of fruit genera used by pitheciids in habitat fragments and continuous forest. Our findings demonstrate that pitheciids use a variety of fruit genera, but phylogenetic and geographic patterns in fruit use are not consistent across all pitheciid genera. This study represents the most extensive examination of pitheciid fruit consumption to date, but future research is needed to investigate the extent to which the trends in fruit genus richness noted here are attributable to habitat differences among study sites, differences in feeding ecology, or a combination of both.

Terrestrial activity in pitheciins (Cacajao, Chiropotes, and Pithecia).

Neotropical monkeys of the genera Cacajao, Chiropotes, and Pithecia (Pitheciidae) are considered to be highly arboreal, spending most of their time feeding and traveling in the upper canopy. Until now, the use of terrestrial substrates has not been analyzed in detail in this group. Here, we review the frequency of terrestrial use among pitheciin taxa to determine the ecological and social conditions that might lead to such behavior. We collated published and unpublished data from 14 taxa in the three genera. Data were gleaned from 53 published studies (including five on multiple pitheciin genera) and personal communications of unpublished data distributed across 31 localities. Terrestrial activity was reported in 61% of Pithecia field studies (11 of 18), in 34% of Chiropotes studies (10 of 29), and 36% of Cacajao studies (4 of 11). Within Pithecia, terrestrial behavior was more frequently reported in smaller species (e.g. P. pithecia) that are vertical clingers and leapers and make extensive use of the understory than in in the larger bodied canopy dwellers of the western Amazon (e.g. P. irrorata). Terrestrial behavior in Pithecia also occurred more frequently and lasted longer than in Cacajao or Chiropotes. An apparent association was found between flooded habitats and terrestrial activity and there is evidence of the development of a "local pattern" of terrestrial use in some populations. Seasonal fruit availability also may stimulate terrestrial behavior. Individuals also descended to the ground when visiting mineral licks, escaping predators, and responding to accidents such as a dropped infant. Overall, the results of this review emphasize that terrestrial use is rare among the pitheciins in general and is usually associated with the exploitation of specific resources or habitat types.