Steroidal and triterpenoidal glucosides from Passiflora alata

Passifetilactones A-E, Fatty Acid Lactones from the Fruit and Flowers of Passiflora foetida with Cytotoxic Activity

Phytochemical investigation of the fruit and flowers of Passiflora foetida led to the isolation of 14 compounds, of which five are previously undescribed fatty acid lactones. Four 2-pyrones, passifetilactones A-D (1-4), and one furanone, passifetilactone E (5), were identified by analysis of spectroscopic and spectrometric data. The previously undescribed lactones were tested for cytotoxic activities against the cancer cell lines HeLa, A549, PC-3, KKU-055, and KKU-213A and two normal cell lines, Vero and MMNK-1. Passifetilactones B (2) and C (3) displayed good to mild cytotoxic activity, at IC50 3.7-25.9 μM and 12.2-19.8 μM, respectively, against six cell lines, but were weakly active against the MMNK-1 cell line. Passifetilactones B and C (2 and 3) showed cell apoptosis induction on the KKU-055 cell line in a flow cytometry experiment. Passifetilactone D (4) is an isolation artifact produced by purification over silica gel, but we demonstrated that it can also be slowly formed within the crude EtOAc extract. This is the first investigation of the flowers and the fruit of this plant.

1H NMR-based metabolic profile and chemometric analysis for the discrimination of Passiflora species genotypic variations

The species of the genus Passiflora (Passifloraceae family) have been used as food, cosmetic and traditional herbal. As a result, the Passiflora species are widely cultivated and has an economic, medicinal and ornamental importance. The popular designation as "passion fruit" and chemical profile of several Passiflora species remains unknown. The lack of chemical information contributes to the erroneous classification and adulteration. In recent years, special attention has been paid to the bioactivity and phytochemical profiles of several Passiflora species extracts. In this research, ¹H NMR-based metabolic profiling coupled with chemometric tools was used to characterize and distinguish extracts obtained from different wild Passiflora species (P. alata, P. cincinnata, and P. setacea) and genetic varieties (P. alata var. BRS Pérola do Cerrado, P. cincinnata var. BRS Sertão Forte, and P. setacea var. BRS Pérola do Cerrado). Fourteen metabolites were identified by 1D and 2D NMR experiments, highlighting the presence of fatty acids, carbohydrates, saponins, alkaloids, and mainly C-glycosidic flavones. Principal components analysis (PCA) allowed discrimination of Passiflora extracts, which the quadranguloside, oleanolic acid-3-sophoroside, α-glucose, β-glucose, and vitexin-2-O"-rhamnoside were relevant in the differentiation of P. alata and P. alata var. BRS Pérola do Cerrado, while the flavones isovitexin and isovitexin-2-O"-xyloside were dominant in the grouping of P. setacea and P. setacea var. BRS Pérola do Cerrado, and finally P. cincinnata and P. cincinnata var. BRS Sertão Forte grouped by the influence of the fatty acids, sucrose, flavones (isoorientin and vitexin-2-O"-xyloside), and trigonelline. The varieties of P. setacea, and P. cincinnata are chemically equivalent to the original Passiflora species. However, the PCA analysis showed that the genetic variety of P. alata occupied a different position in the scores plot provoked mainly by the presence of oleanolic acid-3-sophoroside. The ¹H NMR metabolic profile can be efficient for quality control evaluation, and can contribute to the investigation of new alternatives for official Passiflora herbal medicines.

Triterpenoid Saponins From the Fruit of Acanthopanax senticosus (Rupr. & Maxim.) Harms

Five new oleanane-type triterpenoid saponins (1–5), together with 24 known saponins (6–29) were isolated from the fruit of Acanthopanax senticosus. Their structures were determined by extensive spectroscopic analysis, including 1D, 2D nuclear magnetic resonance (NMR), and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), in combination with chemical methods (acid hydrolysis). The neuroinflammation model was established by lipopolysaccharide (LPS)-induced BV2 microglia, and the neuroprotective effects of all compounds (1–29) were evaluated.

A comparative study of phytoconstituents and antibacterial activity of in vitro derived materials of four Passiflora species

Passiflora species are well known for their common use in popular medicine for the treatment of several diseases, such as insomnia, anxiety, and hysteria, in addition to their anti-inflammatory, antioxidant, analgesic and antibacterial potential. However, few data about the chemical composition and the medicinal potential of in vitro derived materials are available. Therefore, the goal of this work was to compare, for the first time, the phytoconstituents of in vitro derived materials of four Passiflora species, and evaluate the antibacterial potential of their extracts against 20 Gram-positive and negative strains. Chromatographic analysis indicated the presence of saponins in roots extracts from all studied species, whereas leaf extracts presented both saponins and flavonoids. Extracts from leaves and roots of P. alata and P. foetida exhibited a selective inhibitory activity against B. thuringiensis and S. pyogenes, which might be related to the presence of a high concentration of secondary metabolites, including flavonoids and saponins.

The arms race between heliconiine butterflies and Passiflora plants - new insights on an ancient subject

Heliconiines are called passion vine butterflies because they feed exclusively on Passiflora plants during the larval stage. Many features of Passiflora and heliconiines indicate that they have radiated and speciated in association with each other, and therefore this model system was one of the first examples used to exemplify coevolution theory. Three major adaptations of Passiflora plants supported arguments in favour of their coevolution with heliconiines: unusual variation of leaf shape within the genus; the occurrence of yellow structures mimicking heliconiine eggs; and their extensive diversity of defence compounds called cyanogenic glucosides. However, the protection systems of Passiflora plants go beyond these three features. Trichomes, mimicry of pathogen infection through variegation, and production of extrafloral nectar to attract ants and other predators of their herbivores, are morphological defences reported in this plant genus. Moreover, Passiflora plants are well protected chemically, not only by cyanogenic glucosides, but also by other compounds such as alkaloids, flavonoids, saponins, tannins and phenolics. Heliconiines can synthesize cyanogenic glucosides themselves, and their ability to handle these compounds was probably one of the most crucial adaptations that allowed the ancestor of these butterflies to feed on Passiflora plants. Indeed, it has been shown that Heliconius larvae can sequester cyanogenic glucosides and alkaloids from their host plants and utilize them for their own benefit. Recently, it was discovered that Heliconius adults have highly accurate visual and chemosensory systems, and the expansion of brain structures that can process such information allows them to memorize shapes and display elaborate pre-oviposition behaviour in order to defeat visual barriers evolved by Passiflora species. Even though the heliconiine-Passiflora model system has been intensively studied, the forces driving host-plant preference in these butterflies remain unclear. New studies have shown that host-plant preference seems to be genetically controlled, but in many species there is some plasticity in this choice and preferences can even be induced. Although much knowledge regarding the coevolution of Passiflora plants and heliconiine butterflies has accumulated in recent decades, there remain many exciting unanswered questions concerning this model system.

Isolation of C-glycosylflavonoids with α-glucosidase inhibitory activity from Passiflora bogotensis Benth by gradient high-speed counter-current chromatography

In this study, we applied a gradient High-Speed Counter-Current Chromatography (HSCCC) method that allowed, by direct injection of an aqueous crude extract of the leaves of Passiflora bogotensis, the successful isolation of six flavonoids in a single run, with purity of each compound higher than 81%. This separation enabled the isolation of two new flavonoid glycosides, apigenin-6-C-α-l-rhamnopyranosyl-(1→2)-(6″-O-acetyl)-β-d-glucopyranoside (2) and luteolin-6-C-α-l-rhamnopyranosyl-(1→2)-(6″-O-acetyl)-β-d-glucopyranoside (4), and four known ones, isovitexin (1), isoorientin (3), isovitexin-2″-O-rhamnoside (5) and isoorientin-2″-O-rhamnoside (6). The structures of the isolated compounds were identified by HPLC-DAD, LC-MS, (1)H and (13)C NMR and comparison with literature data. The inhibitory activities of all of these compounds were evaluated in vitro on α-glucosidase from S. cerevisiae, and the IC50 was determinate. This is the first study concerning the chemical composition and biological activity of Passiflora bogotensis.

Analysis of C-glycosyl flavonoids from South American Passiflora species by HPLC-DAD and HPLC-MS

INTRODUCTION

Leaves and fruits of Passiflora species are widely used around the world in popular medicine, mainly as sedatives and tranquilisers. C-glycosyl flavonoids are the main components of these species.

OBJECTIVE

To investigate the constituent patterns and to develop a chromatographic method for the characterisation of the C-glycosyl flavonoids profile of the extracts of the leaves and the pericarp of South American Passiflora species.

METHODOLOGY

The chemical composition of extracts from the leaves and the fruits' pericarp of Passiflora edulis var. flavicarpa, P. edulis var. edulis, Passiflora alata, Passiflora tripartita var. mollissima, Passiflora quadrangularis, Passiflora manicata and Passiflora ligularis was evaluated for the presence of C-glycosyl flavonoids. Two separate HPLC methods were developed suitable for a diode array detector (DAD) and a MS detector. Separation by HPLC-DAD was achieved on a Luna C-18 column, using solvent A (tetrahydrofuran-isopropanol-acetonitrile) and solvent B (H₃PO₄ 0.5%) in an isocratic elution mode. In the HPLC-MS, the components were separated on a Luna RP-18A column by a gradient elution (water-acetonitrile-formic acid).

RESULTS

The presence of C-glycosyl flavonoids was identified in leaves and pericarp of P. edulis var. flavicarpa, P. alata, P. edulis var. edulis and P. tripartita var. molissima, but only in leaf extracts of P. quadrangularis and P. manicata and not at all in P. ligularis. The different species and varieties showed different major constituents. The C-glycosyl flavonoids identified more frequently were orientin, isoorientin, vitexin and isovitexin.

CONCLUSION

The methods established are simple and can be used as a tool for the characterisation and quality control of pharmaceutical preparations containing these Passiflora extracts.

Toxicity and genotoxicity evaluation of Passiflora alata Curtis (Passifloraceae)

Passiflora alata is an official species of Brazilian Pharmacopoeia and its aerial parts are used as medicinal plant by local population as well as constitutes many phytomedicines commercialized in Brazil as sedative.

AIMS OF STUDY

To evaluate the acute and sub-acute toxicity and genotoxicity of an aqueous spray-dried extract (PA) of Passiflora alata (2.6% flavonoids).

MATERIALS AND METHODS

The acute and the sub-acute toxicity was evaluated in mice and rats, respectively. Behavioural, biochemical, hematological, histological and urine parameters were considered. Genotoxicity was assessed by using micronucleus test performed in peripheral blood and bone marrow cells and comet assay in peripheral blood leukocytes.

RESULTS

Mice deaths were not observed up to 4800 mg/kg, p.o., single dose. Rats treated with aqueous extract at dose of 300 mg/kg, p.o., for 14 days did not present biochemical, hematological or histopathological significant alterations when compared to control group. However, these rats showed signs of irritability and did not show weight gain. In addition, mice acutely treated with extract 150, 300 and 600 mg/kg, p.o., presented DNA damage determined by comet assay in peripheral blood cells 3h after treatment. The effect of lower doses (12.5, 25 and 50mg/kg, p.o.) was evaluated at 3, 6 and 24h after treating. Only PA 50mg/kg (p.o.) induced significant damage at 3 and 6h. The maximum damage induction was observed at 6h. When the animals received PA 12.5, 25 or 50mg/kg/day during 3 days (i.e., 72h treatment) DNA damage (comet and micronucleus tests) increased significantly in a dose-dependent manner.

CONCLUSION

In conclusion Passiflora alata presented genotoxic effect and deserves further toxicity evaluation in order to guarantee its safety for human use.

Evaluation of anxiolytic activity of spray dried powders of two South BrazilianPassiflora species

The Passiflora extracts have been used in folk medicine because of its reputed sedative and anxiolytic properties. The present study aimed to compare the potential anxiolytic activity of two Passiflora spray-dried powders obtained from P. alata and P. edulis, known in Brazil as 'maracujá'. Male adult Swiss rats were treated with 200, 400 and 800 mg/kg of spray-dried powders p.o. and anxiolytic activity was evaluated using the elevated plus-maze test. The spray-dried powders showed anxiolytic activity in doses of 400 and 800 mg/kg. Our results support the potential anxiolytic effect of Passiflora spray-dried powders (P. alata and P. edulis).

Passiflora actinia Hooker extracts and fractions induce catalepsy in mice

Leaves from several Passiflora species are largely employed in the Brazilian folk medicine for its anxiolytic and sedative properties. In behavioral studies, to analyze the tranquillizer action of Passiflora actinia Hooker, it was noteworthy that animals treated with the hydroethanol (HE) and methanol (ME) extracts presented an abnormal postural immobility compared to control animals. That observation led to an investigation of the effects of HE and its fractions on evaluation of catalepsy in mice. The results showed that HE extract, methanol extract, the sequent aqueous crude fractions (AF), and fa, fb and fc chromatographic fractions obtained from Passiflora actinia induced catalepsy in mice. Apparently, the active principles responsible for catalepsy are present in all of the fractions of the extract.

Cholesterol-dependent hemolytic activity of Passiflora quadrangularis leaves

Plants used in traditional medicine are rich sources of hemolysins and cytolysins, which are potential bactericidal and anticancer drugs. The present study demonstrates for the first time the presence of a hemolysin in the leaves of Passiflora quadrangularis L. This hemolysin is heat stable, resistant to trypsin treatment, has the capacity to froth, and acts very rapidly. The hemolysin activity is dose-dependent, with a slope greater than 1 in a double-logarithmic plot. Polyethylene glycols of high molecular weight were able to reduce the rate of hemolysis, while liposomes containing cholesterol completely inhibited it. In contrast, liposomes containing phosphatidylcholine were ineffective. The Passiflora hemolysin markedly increased the conductance of planar lipid bilayers containing cholesterol but was ineffective in cholesterol-free bilayers. Successive extraction of the crude hemolysin with n-hexane, chloroform, ethyl acetate, and n-butanol resulted in a 10-fold purification, with the hemolytic activity being recovered in the n-butanol fraction. The data suggest that membrane cholesterol is the primary target for this hemolysin and that several hemolysin molecules form a large transmembrane water pore. The properties of the Passiflora hemolysin, such as its frothing ability, positive color reaction with vanillin, selective extraction with n-butanol, HPLC profile, cholesterol-dependent membrane susceptibility, formation of a stable complex with cholesterol, and rapid erythrocyte lysis kinetics indicate that it is probably a saponin.

LC and UV determination of flavonoids from Passiflora alata medicinal extracts and leaves

The leaves of Passiflora alata Curtis (an official species in the Brazilian Pharmacopoeia) are used to treat anxiety, as antispasmodics and sedatives. The development of new analytical methods for analysing flavonoids in Passiflora species is needed in order to improve the quality assurance of the plant and derived extracts and phytomedicines. A survey on the profile of flavonoids and content of isovitexin in the leaves and fluidextract of P. alata through LC was carried out, comparing its chromatographic profiles with a commercial P. incarnata fluidextract. Also, the concentration of the total flavonoids of extracts and leaves according to phamarcopoeial photometrical methods was determined and discussed. The fluidextract of P. alata was produced in accordance with the Pharmacopoeia Helvetica method; the presence of isovitexin in both species (which have distinct chromatographic profiles) was evidenced, this being the major flavonoid compound in the P. incarnata (1.198 g%), but not in P. alata (0.018 g%) fluidextract. Only traces of vitexin could be observed in the P. alata, as well as the absence of the other tested flavonoids: orientin and swertisin (P. incarnata markers), hyperoside, rutin, hesperidin and clorogenic acid. The LC developed method was shown to be appropriated for the qualitative and quantitative analyses and for differentiate species, suitable to be applied to commercial sample analysis. The spectrophotometrical results of three different methods described for P. incarnata were not comparable, the best performance being the British Pharmacopoeia method.