Mycoheterotrophic Epirixanthes (Polygalaceae) has a typical angiosperm mitogenome but unorthodox plastid genomes.

BACKGROUND AND AIMS: Fully mycoheterotrophic plants derive carbon and other nutrients from root-associated fungi and have lost the ability to photosynthesize. While mycoheterotroph plastomes are often degraded compared with green plants, the effect of this unusual symbiosis on mitochondrial genome evolution is unknown. By providing the first complete organelle genome data from Polygalaceae, one of only three eudicot families that developed mycoheterotrophy, we explore how both organellar genomes evolved after loss of photosynthesis. METHODS: We sequenced and assembled four complete plastid genomes and a mitochondrial genome from species of Polygalaceae, focusing on non-photosynthetic Epirixanthes. We compared these genomes with those of other mycoheterotroph and parasitic plant lineages, and assessed whether organelle genes in Epirixanthes experienced relaxed or intensified selection compared with autotrophic relatives. KEY RESULTS: Plastomes of two species of Epirixanthes have become substantially degraded compared with that of autotrophic Polygala. Although the lack of photosynthesis is presumably homologous in the genus, the surveyed Epirixanthes species have marked differences in terms of plastome size, structural rearrangements, gene content and substitution rates. Remarkably, both apparently replaced a canonical plastid inverted repeat with large directly repeated sequences. The mitogenome of E. elongata incorporated a considerable number of fossilized plastid genes, by intracellular transfer from an ancestor with a less degraded plastome. Both plastid and mitochondrial genes in E. elongata have increased substitution rates, but the plastid genes of E. pallida do not. Despite this, both species have similar selection patterns operating on plastid housekeeping genes. CONCLUSIONS: Plastome evolution largely fits with patterns of gene degradation seen in other heterotrophic plants, but includes highly unusual directly duplicated regions. The causes of rate elevation in the sequenced Epirixanthes mitogenome and of rate differences in plastomes of related mycoheterotrophic species are not currently understood.

Anti-acetylcholinesterase activity and antioxidant properties of extracts and fractions of Carpolobia lutea.

CONTEXT: There is an unmet need to discover new treatments for Alzheimer's disease. This study determined the anti-acetylcholinesterase (AChE) activity, DPPH free radical scavenging and antioxidant properties of Carpolobia lutea G. Don (Polygalaceae). OBJECTIVE: The objective of this study is to quantify C. lutea anti-AChE, DPPH free radical scavenging, and antioxidant activities and cell cytotoxicity. MATERIALS AND METHODS: Plant stem, leaves and roots were subjected to sequential solvent extractions, and screened for anti-AChE activity across a concentration range of 0.02-200 µg/mL. Plant DPPH radical scavenging activity, reducing power, and total phenolic and flavonoid contents were determined, and cytotoxicity evaluated using human hepatocytes. RESULTS: Carpolobia lutea exhibited concentration-dependent anti-AChE activity. The most potent inhibitory activity for the stem was the crude ethanol extract and hexane stem fraction oil (IC50 = 140 µg/mL); for the leaves, the chloroform leaf fraction (IC50 = 60 µg/mL); and for roots, the methanol, ethyl acetate and aqueous root fractions (IC50 = 0.3-3 µg/mL). Dose-dependent free radical scavenging activity and reducing power were observed with increasing stem, leaf or root concentration. Total phenolic contents were the highest in the stem: ∼632 mg gallic acid equivalents/g for a hexane stem fraction oil. Total flavonoid content was the highest in the leaves: ∼297 mg quercetin equivalents/g for a chloroform leaf fraction. At 1 µg/mL, only the crude ethanol extract oil was significantly cytotoxic to hepatocytes. DISCUSSION AND CONCLUSIONS: Carpolobia lutea possesses anti-AChE activity and beneficial antioxidant capacity indicative of its potential development as a treatment of Alzheimer's and other diseases characterized by a cholinergic deficit.

Effects of aqueous root extract of Carpolobia alba G. Don on sexual behaviour in adult male rats.

Several lines say that a number of natural products, mostly plant based, have been claimed to cure male sexual dysfunction. One of such botanicals is Carpolobia alba G. Don which is used in Cameroon to treat erectile dysfunction and related male sexual debilities. However, the traditional claim has not been scientifically tested. Thirty adult male rats (five groups of six animals) were orally treated daily with distilled water, sildenafil citrate (positive control), 75, 150, 300 mg/kg of C. alba G. Don roots aqueous extract. The erection and ejaculation properties were recorded on the first, seventh and fourteenth day of treatment by following copulation settings: number of erections (NE), mount frequency (MF), intromission frequency (IF), ejaculation frequency (EF), mount latency (ML), intromission latency (IL), ejaculation latency (EL), average interval of copulation (AIC) and post-ejaculatory interval (PEI). The extract resulted in an improvement of copulation parameters through significant reduction (p < .001) of PEI, ML and IL and significant increase (p < .001) in the NE, MF, IF, EF, EL and AIC. These results indicate a pro-erectile and pro-ejaculatory potential of aqueous root extract of this plant in male rats.

Evolution of mycoheterotrophy in Polygalaceae: The case of Epirixanthes.

PREMISE OF THE STUDY: The mycoheterotrophic lifestyle has enabled some plant lineages to obtain carbon from their mycorrhizal symbionts. The mycoheterotrophic genus Epirixanthes (Polygalaceae) consists of six species from tropical Asia. Although it is probably closely related to the chlorophyllous genus Salomonia and linked to arbuscular mycorrhizal fungi, lack of DNA sequence data has thus far prevented these hypotheses from being tested. Therefore, the evolutionary history of Epirixanthes remains largely unknown. METHODS: We reconstructed the phylogenetic relationships of Epirixanthes based on nuclear ITS and plastid matK data. Divergence times were inferred using a Bayesian relaxed clock approach, and we phylogenetically analyzed its mycorrhizal symbionts. We furthermore assigned these symbionts to operational taxonomic units, compared them with symbionts of other Polygalaceae, and measured their phylogenetic diversity. KEY RESULTS: We found that Epirixanthes is placed in tribe Polygaleae as sister to Salomonia. Epirixanthes has a Miocene-Oligocene stem age and grows exclusively in symbiosis with fungi of Glomeraceae. Salomonia and some Polygala species are linked to both Glomeraceae and Acaulosporaceae, resulting in higher phylogenetic diversity values. The majority of the symbionts of Epirixanthes are not found in Salomonia or Polygala, although a few shared fungal taxa are found. CONCLUSIONS: Epirixanthes forms a relatively young mycoheterotrophic lineage. The Oligocene-Miocene origin suggests its evolution was influenced by the environmental dynamics in Southeast Asia during this time. Although comparison of fungi from Epirixanthes with those from Salomonia and Polygala suggests some specialization, many other mycoheterotrophic plants are linked to a more narrow set of Glomeraceae.

A new xanthone from Moutabea guianensis Aubl.

The ethyl acetate extract of the roots of Moutabea guianensis gave 1,6-dihydroxy-4,7,8-trimethoxy-9H-xanthen-9-one (1), a new xanthone. The isolation was accomplished by column chromatography on silica gel and the structural elucidation of this compound was established by spectroscopic analyses including 1D and 2D NMR and HRESIMS.

Xanthones from the roots of Moutabea guianensis Aubl.

The phytochemical investigation of Moutabea guianensis roots led to the isolation of five polyoxygenated xanthones, including two new ones named moutabeone B (1,8-dihydroxy-4,5,6,7-tetramethoxyxanthone) and moutabeone C (1-hydroxy-4,5,6,7,8-pentamethoxyxanthone), along with the three known xanthones, 1,8-dihydroxy-4,6-dimethoxyxanthone, 1,8-dihydroxy-4,5,6-trimethoxyxanthone and augustin A (1,8-dihydroxy-4,6,7-trimethoxyxanthone). Structural characterization of all compounds was established on the basis of spectroscopic methods, mainly 1D and 2D nuclear magnetic resonance (NMR) and comparison with literature data. The antioxidant activity of compounds was tested through a thin layer chromatography (TLC) bioautography assay using 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH·) as detection reagent. All tested compounds were more active (DL < 0.13-0.03 µg) than Trolox (DL < 0.15 µg), used as reference standard.

Protective effect of Basella alba and Carpolobia alba extracts against maneb-induced male infertility.

CONTEXT: Male infertility is one of the leading causes of social frustration and marginalization, mainly in the developing world. It is attributed to many factors including exposure to agropesticides such as manganese ethylenebis (dithiocarbamate) (maneb), which is one of the most frequently used fungicides in Cameroon. Previous reports support efficiency of some medicinal plants commonly used in Cameroonian folk medicine for the treatment of this disorder. OBJECTIVE: The present study was aimed at assessing the protective effect of extracts from selected plant species, namely Basella alba L. (Basellaceae) (MEBa) and Carpolobia alba G. Don (Polygalaceae) (AECa), in alleviating the maneb-induced impairment of male reproductive function in Wistar albino rats. MATERIALS AND METHODS: The rats were treated with vehicle, plant extract (MEBa or AECa), maneb and maneb plus plant extract, respectively, and their fertility was assessed. Animals were thereafter sacrificed and organs (liver, kidneys and reproductive organs) were dissected out and weighed. Serum androgens together with alanine aminotransferase, liver glutathione and thiobarbituric acid reactive species (TBARS) were also measured. RESULTS AND DISCUSSION: From this study, both plant extracts stimulated testosterone and improved fertility. Administration of MEBa plus maneb prevented fertility reduction by maneb and minimized the inhibitory effect of maneb on testosterone levels. AECa also improved fertility of the maneb-exposed rats, though without restoring testosterone levels, and other investigated parameters remained unaffected by different treatments. CONCLUSION: These findings emphasized the beneficial effects of B. alba and C. alba extracts on male fertility, and suggest their protective effect against maneb-induced toxicity in male reproductive function.

Pollen viability of Polygala paniculata L. (Polygalaceae) using different staining methods.

Polygala paniculata L. is a medicinal plant that grows in the Brazilian Atlantic coast, known as 'barba-de-São-João', 'barba-de-bode', 'vassourinha branca', and 'mimosa'. In this study, pollen viability was estimated by three different staining methods: 2% acetic orcein, 2% acetic carmine, and Alexander's stain. The young inflorescences of twenty accessions were collected and fixed in a solution of ethanol: acetic acid (3:1) for 24 hours, then stored in ethanol 70% under refrigeration. Six slides per plant, two for each stain, were prepared by squashing, and 300 pollen grains per slide were analyzed. Pollen viability was high (> 70%) for most accessions of P. paniculata using the Alexander's stain, which proved the most adequate method to estimate pollen viability.

A new benzophenone, and the antiplasmodial activities of the constituents of Securidaca longipedunculata fresen (Polygalaceae).

Extracts from Securidaca longipedunculata showed antiplasmodial activities against reference clones and clinical isolates using SYBR Green I method. A new benzophenone, 2,3,4,5-tetramethoxybenzophenone (1) was isolated and characterized along with seven known compounds: 4-hydroxy-2,3-dimethoxybenzophenone (2); 3-hydroxy-5-methoxybiphenyl (3), methyl-2-hydroxy-6-methoxybenzoate (4), benzyl-2-hydroxy-6-methoxybenzoate (5), 2-hydroxy-6-methoxybenzoic acid (6), 2,4,5-trimethoxybenzophenone (7) and 2-methoxy-3,4-methylenedioxybenzophenone (8). Compounds 1 and 2 showed ex vivo antiplasmodial activities (IC50 28.8 µM and 18.6 µM, respectively); while 5 and 8 showed in vivo activities (IC50 19.7 µM and 14.5 µM, respectively) against D6 strain. In a cytotoxicity assay, all the extracts (with an exception of the MeOH extract of the leaves) and pure compounds were not toxic to the normal LO2 and BEAS cell-lines, while the methanol roots extract (IC50 66.4 µg/mL against A549, and 77.4 µg/mL against HepG2), compounds 6 (IC50 22.2 µM against A549) and 7 (IC50 45.2 µM against HepG2) were weakly active against cancerous cell-lines.

Anti-nociceptive effects of Carpolobia lutea G. Don (Polygalaceae) leaf fractions in animal models.

Leaves from Carpolobia lutea (Polygalaceae) were screened to establish the antiulcer ethnomedicinal claim and to quantitatively isolate, elucidate the active compounds by semi-preparative HPLC. The anti-nociceptive effects of Carpolobia lutea (CL) G. Don (Polygalaceae) organic leaf extracts were tested in experimental models in mice. The anti-nociceptive mechanism was determined using tail-flick test, acetic acid-induced abdominal constrictions, formalin-induced hind paw licking and the hot plate test. The fractions (ethanol, ethyl acetate, chloroform, n-hexane) and crude ethyl acetate extract of CL (770 mg/kg, i.p.) produced significant inhibitions of both phases of the formalin-induced pain in mice, a reduction in acetic acid-induced writhing as well as and an elevation of the pain threshold in the hot plate test in mice. The inhibitions were greater to those produced by indomethacin (5 mg/kg, i.p.). Ethyl acetate fraction revealed cinnamic and coumaric acids derivatives, which are described for the first time in literature. These cinnamalglucosides polyphenols characterised from CL may in part account for the pharmacological activities. These findings confirm its ethnomedical use in anti-inflammatory pain and in pains from gastric ulcer-associated symptoms.

Antidiarrheal mechanism of Carpolobia lutea leaf fractions in rats.

CONTEXT: Carpolobia lutea G. Don (Polygalaceae) leaf is reputable as an antidiarrheal agent among the Efik and Ibibio tribe of Akwa Ibom State, Nigeria. The crude extract is reported to show antidiarrheal and antiulcer effects in rodents. OBJECTIVE: The isolation and characterization of drug molecules from the leaf fraction with antidiarrheal bioactivity and determination of mechanism of action are reported. MATERIAL AND METHODS: Gradient extraction by maceration yielding n-hexane, chloroform, ethyl acetate, and ethanol fractions (770 mg/kg) were used to establish the fractions suitable for drug discovery. The antidiarrheal effect of the leaf fractions of Carpolobia lutea was evaluated using castor oil-induced diarrhea, castor oil-induced intestinal transit, and enteropooling. RESULTS: Results indicate that all fractions produced a significant (p < 0.01-0.001) decrease in castor oil-induced diarrhea in rats. This effect was not antagonized by isosorbide dinitrate (150 mg/kg, p.o), diphenoxylate (5 × 10⁻³ mg/kg p.o) and yohimbine (1 mg/kg, s.c.) except for the chloroform fraction. The ethyl acetate fraction produced 100% inhibition of intestinal transit, an effect greater than pure drug. Phytochemical analysis of the ethyl acetate fraction yielded polyphenolic compounds. CONCLUSION: The leaf fractions contain two types of antidiarrheal agents, one mediating its effect through α1-presynaptic adrenoceptor while the other does not. Polyphenols isolated may in part lend credence for observed antidiarrheal activity.

In vivo antimalarial activities of ethanolic crude extracts and fractions of leaf and root of Carpolobia lutea.

Carpolobia lutea (leaves and root) is used traditionally as malarial remedy by the Ibibios of Niger Delta of Nigeria and Benin. This study was aimed to investigate the antiplasmodial potentials of the crude leaf and root extracts of this plant as well as their fractions in vivo in Plasmodium berghei berghei-infected mice to give scientific proof to the ethnobotanical claims and correlate with the reported in vivo activity. The ethanolic extracts of Carpolobia lutea leaf (245-735 mg/kg/day) and root (7-21 mg/kg/day) were screened for blood plasmocidal activity against chloroquine-sensitive Plasmodium berghei in mice. The antimalarial activity in 4-day and curative tests was evaluated. Carpolobia lutea leaf extract (245-735 mg/kg/day) and fractions exhibited significant (p<0.05-0.01) antiplasmodial activity both in 4-day early infection test and in established infection with a considerable mean survival time which was incomparable to that the standard drug, chloroquine (5 mg/kg/day). The root extract (7-21 mg/kg/day) and fractions also demonstrated a promising blood schizontocidal activity in early and established infections. These plant extracts and fractions possess considerable antiplasmodial activities which justify their use in ethnomedicine and can be exploited in the control of malaria.

Contraceptive, estrogenic and anti-estrogenic potentials of methanolic root extract of Carpolobia lutea in rodents.

Several plants are used in herbal medicine for family planning. Carpolobia lutea is a medicinal plant in South Eastern Nigeria used for family planning. The study was designed to investigate the contraceptive, estrogenic and antiestrogenic potentials of the methanolic root extract of Carpolobia lutea in both rats and mice. The contraceptive effect of extract (7 - 21mg/kg) administered by intraperitoneal route for four days in divided doses was tested in mice and rats. Sexually-active males were introduced on day 5 at the ratio of 3F:1M and kept with these females till the end of the experiment. Investigations on the estrogenic and antiestrogenic property of the extract (7-21mg/kg) were done in immature rats that had undergone surgical removal of both ovaries. The effects of the extract (vaginal opening, vaginal cornification, uterine wet weight) were compared with 17-beta-estradiol (0.1µg/rat/day) as standard drug. Twenty-four hours later, the animals were sacrificed following the last dose and the weights of uterus, kidney, liver and small intestine were recorded. The extract prevented conception in both mice and rats for two gestational periods. Significant changes (p<0.05-0.001) were observed in the length and weight of pups relative to control. There were no abnormalities observed in the pups over thirty days. In ovariectomized immature young rats, the extract showed estrogenic effect (vaginal opening, vaginal cornification and increased uterine wet weight) in low doses while in high doses, it showed anti-estrogenic effect. These findings agree with the traditional use of Carpolobia lutea in the control of fertility. The contraceptive property of the extract may be associated with the direct effects of its chemical constituents.

Fine-scale genetic structure within plots of Polygala reinii (Polygalaceae) having an ant-dispersal seed.

Fine-scale genetic structure within a population was analyzed for the myrmecochorous forest perennial Polygala reinii (Polygalaceae) using allozyme loci. In the analysis, two sampling plots were established to cover the isolated patchy distribution within the study population. Size and spatial structure were also examined for the plots to assess their interaction with the genetic structuring. Allozyme analysis based on 13 putative loci encoding 10 enzyme systems showed high genetic variation and low values of fixation indices at the two plots. Spatial autocorrelation analysis based on the multilocus coancestry coefficient (f ( ij )) revealed significant genetic structuring in both plots, suggesting limited gene-, especially seed-, dispersal within the population. The spatial structure within the plots, assessed by O-ring statistics, was characterized by the occurrence of spatial clustering of individuals within a few meters. In particular, the range of the spatial clustering roughly corresponded to that of the genetic structuring. While the size structure did not significantly differ between the plots, these results indicate that the fine-scale genetic structure reflects the formation of spatial clustering of related individuals within the population, partly due to the restricted ant-mediated seed dispersal in P. reinii.

Antidepressant effects of the extract YZ-50 from Polygala tenuifolia in chronic mild stress treated rats and its possible mechanisms.

YZ-50 is an active fraction obtained from the root of Polygala tenuifolia Willd. (Polygalaceae) extract and it has been reported previously to exert beneficial effects on mental health in depressed sufferers, however, its mechanism of action remains unresolved. This study utilized the chronic mild stress (CMS) model of depression in Sprague-Dawley rats to evaluate the effects of YZ-50 on depressive behaviors. Furthermore, we tested the hypothesis that the capacity of YZ-50 to reverse the harmful effects of CMS is relative to the hypothalamo-pituitary-adrenal (HPA) system and brain-derived neurotrophic factor (BDNF) in the hippocampus. Repeated administration of YZ-50 for 28 days at the doses of 140 and 280 mg/kg in CMS, YZ-50 reversed the CMS-induced changes in sucrose consumption, plasma corticosterone levels and open field activity. In addition, CMS significantly decreased hippocampal BDNF mRNA levels. However, YZ-50 counteracted a decrease in hippocampal BDNF mRNA caused by CMS. In conclusion, YZ-50 reversed the harmful effects of CMS on mood and behaviors in rats and it possesses an antidepressant property that is at least in part mediated by the neuroendocrine and neuropropective systems, and it is likely that the HPA system plays an important role in this process.

Report: In vitro antimicrobial activities of extracts of Carpolobia lutea root.

Several plants are used in folk medicine to treat infections. Carpolobia lutea, G.Don (Polygalaceae) is a medicinal plant commonly used by herbalists in Southern Nigeria against dental and genitourinary infections. The study was to evaluate the in vitro antimicrobial activities of n-hexane, chloroform, ethyl acetate and methanol extracts of Carpolobia lutea root. Four typed cultures of bacteria namely, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis and two clinical strains of fungi, namely Candida albicans and Tinea capitis were analyzed using agar well diffusion method. The extracts that showed antimicrobial activity were then tested to determine the Minimum Inhibitory Concentration for each bacterial or fungal sample.The ethyl acetate extract gave the widest zone of inhibition (21.0 mm) followed by chloroform when tested on E. coli. No inhibition was observed with E.Coli. None of the extracts showed any inhibitory effect against Pseudomonas aeruginosa and the fungal strains of Candida albicans and Tinea capitis. The most potent of these extracts was Chloroform extract with Minimum Inhibitory Concentration (MIC) of 25 mg/ml for bacteria. The phytochemical screening of the root of C. lutea revealed the presence of saponins, anthraquinones, flavonoids, cardiac glycosides, simple sugar and terpenes.

Floral morphology and development in Quillajaceae and Surianaceae (Fabales), the species-poor relatives of Leguminosae and Polygalaceae.

BACKGROUND AND AIMS: Molecular phylogenies have suggested a new circumscription for Fabales to include Leguminosae, Quillajaceae, Surianaceae and Polygalaceae. However, recent attempts to reconstruct the interfamilial relationships of the order have resulted in several alternative hypotheses, including a sister relationship between Quillajaceae and Surianaceae, the two species-poor families of Fabales. Here, floral morphology and ontogeny of these two families are investigated to explore evidence of a potential relationship between them. Floral traits are discussed with respect to early radiation in the order. METHODS: Floral buds of representatives of Quillajaceae and Surianaceae were dissected and observed using light microscopy and scanning electron microscopy. KEY RESULTS: Quillajaceae and Surianaceae possess some common traits, such as inflorescence morphology and perianth initiation, but development and organization of their reproductive whorls differ. In Quillaja, initiation of the diplostemonous androecium is unidirectional, overlapping with the petal primordia. In contrast, Suriana is obdiplostemonous, and floral organ initiation is simultaneous. Independent initiation of five carpels is common to both Quillaja and Suriana, but subsequent development differs; the antesepalous carpels of Quillaja become fused proximally and exhibit two rows of ovules, and in Suriana the gynoecium is apocarpous, gynobasic, with antepetalous biovulate carpels. CONCLUSIONS: Differences in the reproductive development and organization of Quillajaceae and Surianaceae cast doubt on their potential sister relationship. Instead, Quillaja resembles Leguminosae in some floral traits, a hypothesis not suggested by molecular-based phylogenies. Despite implicit associations of zygomorphy with species-rich clades and actinomorphy with species-poor families in Fabales, this correlation sometimes fails due to high variation in floral symmetry. Studies considering specific derived clades and reproductive biology could address more precise hypotheses of key innovation and differential diversification in the order.

Floral morphology and development in Quillajaceae and Surianaceae (Fabales), the species-poor relatives of Leguminosae and Polygalaceae.

BACKGROUND AND AIMS: Molecular phylogenies have suggested a new circumscription for Fabales to include Leguminosae, Quillajaceae, Surianaceae and Polygalaceae. However, recent attempts to reconstruct the interfamilial relationships of the order have resulted in several alternative hypotheses, including a sister relationship between Quillajaceae and Surianaceae, the two species-poor families of Fabales. Here, floral morphology and ontogeny of these two families are investigated to explore evidence of a potential relationship between them. Floral traits are discussed with respect to early radiation in the order. METHODS: Floral buds of representatives of Quillajaceae and Surianaceae were dissected and observed using light microscopy and scanning electron microscopy. KEY RESULTS: Quillajaceae and Surianaceae possess some common traits, such as inflorescence morphology and perianth initiation, but development and organization of their reproductive whorls differ. In Quillaja, initiation of the diplostemonous androecium is unidirectional, overlapping with the petal primordia. In contrast, Suriana is obdiplostemonous, and floral organ initiation is simultaneous. Independent initiation of five carpels is common to both Quillaja and Suriana, but subsequent development differs; the antesepalous carpels of Quillaja become fused proximally and exhibit two rows of ovules, and in Suriana the gynoecium is apocarpous, gynobasic, with antepetalous biovulate carpels. CONCLUSIONS: Differences in the reproductive development and organization of Quillajaceae and Surianaceae cast doubt on their potential sister relationship. Instead, Quillaja resembles Leguminosae in some floral traits, a hypothesis not suggested by molecular-based phylogenies. Despite implicit associations of zygomorphy with species-rich clades and actinomorphy with species-poor families in Fabales, this correlation sometimes fails due to high variation in floral symmetry. Studies considering specific derived clades and reproductive biology could address more precise hypotheses of key innovation and differential diversification in the order.

Effect of pollination on floral longevity and costs of delaying fertilization in the out-crossing Polygala vayredae Costa (Polygalaceae).

BACKGROUND AND AIMS: The effect of pollination on flower life span has been widely studied, but so far little attention has been paid to the reproductive consequences of delayed pollination in plants with long floral life spans. In the present study, Polygala vayredae was used to answer the following questions. (1) How does male and female success affect the floral longevity of individual flowers? (2) How does delaying fertilization affect the female fitness of this species? METHODS: Floral longevity was studied after experimental pollinations involving male and/or female accomplishment, bagging and open pollination. The reproductive costs of a delay in the moment of fertilization were evaluated through fruit set, seed-ovule ratio and seed weight, after pollination of flowers that had been bagged for 2-18 d. KEY RESULTS: Senescence of the flowers of P. vayredae was activated by pollen reception on the stigmatic papillae, while pollen removal had no effect on floral longevity. Nonetheless, a minimum longevity of 8 d was detected, even after successful pollination and pollen dissemination. This period may be involved with the enhancement of male accrual rates, as the female accomplishment is generally achieved after the first visit. Floral life span of open-pollinated flowers was variable and negatively correlated with pollinator visitation rates. Delayed pollination had a major impact on the reproductive success of the plant, with fruit set, seed-ovule ratio and seed weight being significantly diminished with the increase of flower age at the moment of fertilization. CONCLUSIONS: A strong relationship between pollination and floral longevity was observed. Flowers revealed the ability to extend or reduce their longevity, within some limits, in response to the abundance of efficient pollinators (i.e. reproductive fulfilment rates). Furthermore, with scarce or unpredictable pollinators, a long floral life span could maintain the opportunity for fertilization but would also have reproductive costs on production of offspring. Reduced female fitness late in the flower's life could shift the cost-benefit balance towards a shorter life span, partially counteracting the selection for longer floral life span potentially mediated by scarce pollination services.

Anticonvulsant activity of Nylandtia spinosa L. Dumont (Polygalaceae) aqueous and methanol leaf extracts in mice.

Aqueous and methanol leaf extracts of Nylandtia spinosa L. Dumont (Polygalaceae) were evaluated for anticonvulsant activity against tonic seizures produced in mice by pentylenetetrazole (PTZ), bicuculline, picrotoxin, and N-methyl-DL-aspartic acid (NMDLA). Aqueous leaf extract of N. spinosa (50-400 mg/kg, i.p.) and methanol extract (50-400 mg/kg, i.p.) significantly attenuated PTZ (95 mg/kg, i.p.)-induced tonic seizures. Doses of 400 mg/kg (i.p.) and 100-400 mg/kg (i.p.) of aqueous extract of N. spinosa significantly delayed the onset of tonic seizures elicited by bicuculline (35 mg/kg, i.p.) and picrotoxin (12 mg/kg, i.p.), respectively. Methanol extract (200-400 mg/kg, i.p.) and (50-400 mg/kg, i.p.) significantly delayed the onset of tonic seizures induced by bicuculline (35 mg/kg, i.p.) and picrotoxin (12 mg/kg, i.p.), respectively, whereas 400 mg/kg (i.p.) significantly reduced the incidence of picrotoxin (12 mg/kg, i.p.)-induced seizures. Both aqueous and methanol leaf extracts of N. spinosa did not affect NMDLA (400 mg/kg, i.p.)-induced tonic seizures. Phenobarbitone (12.5 mg/kg, i.p.) and diazepam (0.5 mg/kg, i.p.) antagonized tonic seizures induced by PTZ (95 mg/kg, i.p.), bicuculline (35 mg/kg, i.p.), and picrotoxin (12 mg/kg, i.p.) but did not affect NMDLA (400 mg/kg, i.p.)-induced seizures. Phenytoin (30 mg/kg, i.p.) did not alter the tonic seizures produced by either PTZ (95 mg/kg, i.p.), bicuculline -2-(35 mg/kg, i.p.), or picrotoxin (12 mg/kg, i.p.). The results obtained indicate that both aqueous and methanol leaf extracts of N. spinosa possess anticonvulsant property, thus justifying the use of the plant by traditional medicine practitioners in the treatment of epilepsy. The relatively high LD(50) of greater than 3600 mg/kg (p.o.) and 1780 mg/kg (i.p.) obtained with the aqueous extract suggest that the plant is relatively safe in mice. The phytochemical analysis carried out showed the presence of tannins, saponins, reducing sugars, alkaloids, flavonoids, triterpene steroids, and cardiac glycosides in the plant material.