Chemical characterization and antioxidant potential of ecuadorian propolis.

The chemical composition and the antioxidant potential of Ecuadorian propolis samples (n = 19) collected in different provinces were investigated. HPLC-DAD-ESI/MSn and GC-EI-MS analysis of the methanol extracts enabled us to define six types of Ecuadorian propolis based on their secondary metabolite composition. 68 compounds were identified, 59 of which are reported for the first time in Ecuadorian propolis. The detected compounds include flavonoids, diterpenes, triterpenes, organic acid derivatives, alkylresorcinol derivatives and nemorosone. Plants belonging to genera Populus, Mangifera and Clusia seemed to be vegetable sources employed by bees to produce Ecuadorian propolis. Total phenolic content and antioxidant activity of propolis extracts were determined by the Folin-Ciocalteu assay and 2,2-diphenyl-1-picrylhydrazyl and ferric reducing/antioxidant potential assays, respectively. As expected, the variable chemical composition affected the differences in terms of antioxidant potential.

Bracken fern does not diminish arbuscular mycorrhizal fungus inoculum potential in tropical deforested areas.

Tropical montane forests are threatened by uncontrolled fire events because of agricultural expansion. Consequently, deforested areas frequently are dominated by the bracken fern, Pteridium spp., for long periods, and forest regeneration is limited. Despite considerable research on bracken-dominated ecosystems, little is known about the relationship between bracken mycorrhizal fungi and tree seedlings. Arbuscular mycorrhizal fungi (AMF) form symbiotic relationships with terrestrial plants, providing nutrients and protection against pathogens and promoting seedling growth and establishment. Therefore, AMF inoculum have high potential for forest restoration programs. Here, we compare the species diversity of AMF spores, root colonization, and seedling growth of Clusia trochiformis 1 year after the addition of different liquefied root inocula: forest conspecific, forest heterospecific, and from Pteridium rhizomes. Thirteen morphospecies of arbuscular mycorrhizal fungi were identified on the roots of C. trochiformis, and Glomus spp. were the most abundant in all treatments. No differences were observed in spore species richness and diversity among treatments, but spore density was the highest subsequent to the Pteridium inoculum. There was no significant difference in mycorrhizal root colonization and seedling growth of C. trochiformis among inoculated treatments. We found a positive relation between root colonization and total biomass. This study shows that the AMF communities in bracken areas and forests present similar characteristics and that the bracken fern does not limit AMF inoculum potential, favouring seedling growth of Clusia.

Utilization of the Plant Clusia Fluminensis Planch & Triana Against Some Toxic Activities of the Venom of Bothrops jararaca and B. jararacussu Snake Venom Toxic Activities.

BACKGROUND: In Brazil, the Bothrops genus accounts for 87% of registered snakebites, which are characterized by hemorrhage, tissue necrosis, hemostatic disturbances, and death. The treatment recommended by governments is the administration of specific antivenoms. Although antivenom efficiently prevents venom-induced lethality, it has limited efficacy in terms of preventing local tissue damage. Thus, researchers are seeking alternative therapies able to inhibit the main toxic effects of venoms, without compromising safety. OBJECTIVE: The study aimed to test the ability of aqueous extracts of leaves, stems, and fruits of the plant Clusia fluminensis to neutralize some toxic effects induced by the venoms of Bothrops jararaca and Bothrops jararacussu. METHODS: The plant extracts were incubated with venoms for 30 min. at 25 °C, and then in vitro (coagulant and proteolytic) and in vivo (hemorrhagic, myotoxic, and edematogenic) activities were evaluated. In addition, the extracts were administered to animals (by oral, intravenous or subcutaneous routes) before or after the injection of venom samples, and then hemorrhage and edema assays were performed. In addition, a gel solution of the fruit extract was produced and tested in terms of reducing hemorrhage effects. A chemical prospection was performed to identify the main classes of compounds present in the extracts. RESULTS: All the extracts inhibited the activities of the two venoms, regardless of the experimental protocol or route of administration of the extracts. Moreover, the gel of the fruit extract inhibited the venom-induced-hemorrhage. The extracts comprised of tannins, flavonoids, saponins, steroids, and terpenoids. CONCLUSION: Antivenom properties of C. fluminensis extracts deserve further investigation in order to gain detailed knowledge regarding the neutralization profile of these extracts.

Clusia criuva Cambess. (Clusiaceae): anatomical characterization, chemical prospecting and antioxidant activity

ABSTRACT This study aims the anatomical description and chemical characterization of aerial parts of Clusia criuva Cambess., Clusiaceae in addition to the evaluation of the antioxidant activity of crude extracts, correlated to the flavonoid content. The morphological characterization was performed using traditional techniques of plant anatomy. For phytochemical studies, crude extracts were obtained by static maceration and analyzed by thin layer chromatography. The antioxidant activity and the flavonoids content were determined by colorimetric methods involving, respectively, 2,2-diphenyl-1-picrylhydrazyl free radical and aluminum chloride. C. criuva has uniseriate epidermis, paracytic stomata, hypostomatic leaves, cuticular flanges and cordiform vascular cylinder with accessory bundles. Chemical prospecting confirmed the abundant presence of terpenes and phenols in the extracts of leaves and of fruits. The methanolic extract of seeds showed the lowest EC50 value, but the methanolic extract of pericarps exhibited the highest maximum antioxidant activity. The results suggested a high percentage of flavonoids in the hexanic extract of pericarps, however, this could represent, in fact, the presence of benzophenones. Secretory ducts and the shape of the midrib are diagnostic for C. criuva. The antioxidant activity is not directly related to the flavonoids. The results indicate the importance of future studies with C. criuva chemical constituents.

Phytochemical study and evaluation of cytotoxic and genotoxic properties of extracts from Clusia latipes leaves

Abstract Some species of the Clusia genus have been shown to have important biomedical properties, including the ability to inhibit tumor growth in vitro and the usefulness for skin care. In this study, we examined the cytotoxic effect of hexane, ethyl acetate and methanol extracts from Clusia latipes Planch. & Triana, Clusiaceae, leaves on survival of human prostate cancer cells (PC-3), colon cancer cells (RKO), astrocytoma cells (D-384), and breast cancer cells (MCF-7). The ethyl acetate extract displayed the most substantial cytotoxic effect. However, using a Comet assay, we observed that the hexane extract induced a genotoxic effect (DNA damage) on human lymphocytes in an in vitro model. Chromatographic purification of the C. latipes hexane extract led to the isolation and identification of friedelin, friedolan-3-ol, and hesperidin as active cytotoxic compounds in hexane extract, while β-amyrine was identified as an active cytotoxic compound in the ethyl acetate extract of C. latipes, thereby supporting further studies of the molecular mechanisms underlying the effect of these secondary metabolites on cancer cell survival.

New Polyprenylated Phloroglucinol and Other Compounds Isolated from the Fruits of Clusia nemorosa (Clusiaceae).

Clusia nemorosa has been widely used in folk medicine to treat various ailments, including headaches and inflammation. Investigation of the fruits of Clusia nemorosa (Clusiaceae) led to the isolation and characterization of a new phloroglucinol derivative, named 6S,8S,28S-nemorosic acid (1), together with seven known compounds: friedelin (2), ß-sitosterol (3), stigmasterol (4), ß-sitosterol glycoside (5), kaempferol (6), quercetin (7) and dimethyl citrate (8). The structures were determined by extensive 1D- and 2D-NMR, CD and MS spectroscopic analyses.

Biocontrol evaluation of extracts and a major component, clusianone, from Clusia fluminensisPlanch. & Triana againstAedes aegypti

Studies evaluated the effects of hexanic extracts from the fruits and flowers ofClusia fluminensis and the main component of the flower extract, a purified benzophenone (clusianone), against Aedes aegypti. The treatment of larvae with the crude fruit or flower extracts from C. fluminensis did not affect the survival ofAe. aegypti (50 mg/L), however, the flower extracts significantly delayed development of Ae. aegypti. In contrast, the clusianone (50 mg/L) isolate from the flower extract, representing 54.85% of this sample composition, showed a highly significant inhibition of survival, killing 93.3% of the larvae and completely blocking development of Ae. aegypti. The results showed, for the first time, high activity of clusianone against Ae. aegypti that both killed and inhibited mosquito development. Therefore, clusianone has potential for development as a biopesticide for controlling insect vectors of tropical diseases. Future work will elucidate the mode of action of clusianone isolated from C. fluminensis.

Effects of nemorosone, isolated from the plant Clusia rosea, on the cell cycle and gene expression in MCF-7 BUS breast cancer cell lines.

BACKGROUND: Breast cancer is the cause of considerable morbidity and mortality in women. While estrogen receptor antagonists have been widely used in breast cancer treatment, patients have increasingly shown resistance to these agents and the identification of novel targeted therapies is therefore required. Nemorosone is the major constituent of the floral resin from Clusia rosea and belongs to the class of polycyclic polyisoprenylated benzophenones of the acylphloroglucinol group. The cytotoxicity of nemorosone in human cancer cell lines has been reported in recent years and has been related to estrogen receptors in breast cancer cells. METHODS: Changes induced by nemorosone in the cell cycle and gene expression of the MCF-7 BUS (estrogen-dependent) breast cancer cell line were analyzed using flow cytometry and the RT(2) Profiler PCR array, respectively. RESULTS: In comparison to breast cancer cells without treatment, nemorosone induced discrete cell cycle arrest in the G1 phase and significant depletion in the G2 phase. Moreover, the compound altered the expression of 19 genes related to different pathways, especially the cell cycle, apoptosis and hormone receptors. CONCLUSION: These promising results justify further studies to clarify mechanisms of action of nemorosone, in view of evaluate the possible use of this benzophenone as adjuvant in the treatment of breast cancer.

Cytotoxic and Antiviral Activity of Extracts and Compounds Isolated from Clusia Fluminensis Planch. & Triana (Clusiaceae) / Atividade Citotóxica e Antiviral de Extratos e Compostos Isolados de Clusia Fluminensis Planch. & Triana (Clusiaceae)

The worldwide distribution of herpes simplex virus type 1 (HSV-1) allied to the emergence of resistant strains makes necessary and urgent the search and development of new substances capable of preventing and treating HSV-1 infections. Studies demonstrate synergy between genital herpes and human immunodeficiency virus type 1 (HIV-1), which represents a major concern for global public health. Objective: The objective of this study was to evaluate the activity of crude extracts and isolated substances from C. fluminensis in the in vitro replication of the HSV-1 virus and HIV-1-RT activity. Methods: This study evaluated the activity of extracts and isolated compounds from Clusia fluminensis Planch. & Triana against HSV-1 using Vero cells in culture and against HIV-1 using a recombinant reverse transcriptase enzyme (HIV -1 RT). The percentage of inhibition against HSV-1 was determined from viral lysis plaque reduction assay, and the anti-HIV-1-RT test was performed by a fluorimetric assay. It was also evaluated the cytotoxic activity of the samples using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]. Results: The crude extracts showed high percentage of inhibition against HSV-1, reaching 81.4 to 100.0% inhibition in non-cytotoxic concentration (50 µg/mL). The isolated compounds, lanosterol and clusianone, demonstrated 100% inhibition in non-cytotoxic concentration (50 µg/mL). We also examined the effects of the extracts and isolates on the activity of the HIV-1-RT. Among the crude extracts, only the methanolic extract of leaves and methanolic extract of stems showed inhibitory activity against HIV-1-RT. Regarding the isolated compounds, lanosterol showed a moderate activity. Conclusion: Our data demonstrate that extracts and isolates compounds Clusia fluminensis Planch. & Triana have promising antiviral activity inhibiting HSV-1 replication and HIV-1 by inhibiting the anti-RT activity.

A distribuição mundial do vírus herpes simplex tipo 1 (HSV-1) aliada ao surgimento de cepas resistentes torna necessária e urgente a busca e o desenvolvimento de novas substâncias capazes de prevenir e tratar infecções HSV-1. Estudos demonstram sinergia entre herpes genital e vírus da imunodeficiência humana tipo 1 (HIV-1), o que representa uma grande preocupação para a saúde pública global. Objetivo: O objetivo deste estudo foi avaliar a atividade de extratos brutos e substâncias isoladas de Clusia fluminensis Planch. & Triana na replicação in vitro do vírus HSV-1 e na atividade anti HIV-1-RT. Métodos: Este estudo avaliou a atividade de extratos e substâncias isoladas de Clusia fluminensis Planch. & Triana contra o HSV-1 utilizando células Vero em cultura e contra o HIV-1 utilizando a enzima transcriptase reversa recombinante (HIV-1 RT). A porcentagem de inibição contra o HSV-1 foi determinada a partir do ensaio de redução de placas de lise viral, e o ensaio anti-HIV-1 RT foi realizado por um ensaio fluorimétrico. Também foi avaliada a atividade citotóxica das amostras utilizando MTT [brometo de 3- (4,5-dimetiltiazol-2-il) -2,5-difeniltetrazólio]. Resultados: Os extratos demonstraram elevada percentagem de inibição contra o HSV-1, atingindo 81,4 a 100,0% de inibição em concentração não citotóxica (50 µg/mL). Os compostos isolados, lanosterol e clusianona, demonstraram 100% de inibição em concentração não citotóxica (50 µg/mL). Examinamos também os efeitos dos extratos e isolados sobre a atividade anti-HIV-1 RT. Entre os extratos brutos, apenas o extrato metanólico das folhas e caules apresentaram atividade anti-HIV-1 RT. Em relação aos compostos isolados, lanosterol mostrou uma atividade moderada. Conclusão: Nossos dados demonstram que os extratos e compostos isolados de Clusia fluminensis Planch. & Triana possuem atividade antiviral promissora inibindo a replicação do HSV-1 e HIV-1 através da inibição da atividade anti-RT.

Distribution of metabolites in galled and non-galled leaves of Clusia lanceolata and its antioxidant activity

Essential oils of galled and non-galled leaves of Clusia lanceolata Cambess., Clusiaceae, were obtained by hydrodistillation and analyzed by GC and GC/MS. The chemical composition of both oils was similar, with a predominance of sesquiterpene caryophyllenes. The extracts from the leaves were evaluated regarding total phenols, flavonoids and proanthocyanidins. Galled leaves showed higher levels of phenolics and proanthocyanidins, since the content of flavonoids was higher in non-galled leaves. The chromatographic profiles of extracts were obtained by using HPLC/DAD and LC-ESI-MS. Electrospray ionisation (ESI) in positive and negative ion mode was used to identify four flavones C-glycosides in both extracts. The study constitutes a first report on the chemical research of C. lanceolata. The extract from galled leaves had a higher antioxidant activity.

Facultative crassulacean acid metabolism (CAM) plants: powerful tools for unravelling the functional elements of CAM photosynthesis.

Facultative crassulacean acid metabolism (CAM) describes the optional use of CAM photosynthesis, typically under conditions of drought stress, in plants that otherwise employ C3 or C4 photosynthesis. In its cleanest form, the upregulation of CAM is fully reversible upon removal of stress. Reversibility distinguishes facultative CAM from ontogenetically programmed unidirectional C3-to-CAM shifts inherent in constitutive CAM plants. Using mainly measurements of 24h CO2 exchange, defining features of facultative CAM are highlighted in five terrestrial species, Clusia pratensis, Calandrinia polyandra, Mesembryanthemum crystallinum, Portulaca oleracea and Talinum triangulare. For these, we provide detailed chronologies of the shifts between photosynthetic modes and comment on their usefulness as experimental systems. Photosynthetic flexibility is also reviewed in an aquatic CAM plant, Isoetes howellii. Through comparisons of C3 and CAM states in facultative CAM species, many fundamental biochemical principles of the CAM pathway have been uncovered. Facultative CAM species will be of even greater relevance now that new sequencing technologies facilitate the mapping of genomes and tracking of the expression patterns of multiple genes. These technologies and facultative CAM systems, when joined, are expected to contribute in a major way towards our goal of understanding the essence of CAM.

Leaf extract from Clusia nemorosa induces an antinociceptive effect in mice via a mechanism that is adrenergic systems dependent.

Previous studies on the genus Clusia have shown anti-inflammatory and antiproliferative effects of the leaf extracts, but its antinociceptive activity has never been characterized. In the present study, the antinociceptive activity of the hexane extract of the leaves of Clusia nemorosa G. Mey, called HECn, was examined. Antinociceptive activity was evaluated using acetic acid-induced writhing, formalin, and hot-plate tests. All experiments were carried out on male Swiss mice. The extract (1-400 mg·kg(-1)), given by intraperitoneal route (i.p.) 1 h prior to testing, produced a dose-dependent inhibition on the number of abdominal writhings, with an ID50 of 62 mg·kg(-1). In addition, HECn was able to prevent the visceral pain induced by acetic acid in mice for at least 2 h. In the formalin test, HECn had no effect in the first phase, but produced an analgesic effect on the second phase with the inhibition of licking time. The HECn did not show a significant analgesic effect in the hot plate test. Pretreatment with yohimbine attenuated the antinociceptive effect induced by HECn in the writhing test. However, naloxone, atropine, or haloperidol did not affect antinociception induced by HECn in the writhing test. Together, these results indicate that the extract from the leaves of Clusia nemorosa produces antinociception in models of chemical pain through mechanisms that suggest participation of the adrenergic systems pathway.

Gall midge attack intensity and host-plant response in a Neotropical coastal ecosystem / Intensidade do parasitismo de inseto galhador e resposta da planta hospedeira em um ecossistema neotropical costeiro

The gall inducer Clusiamyia nitida Maia, 1996 (Diptera, Cecidomyiidae) often infests the shrub Clusia lanceolata (Camb.) (Clusiaceae) in the Neotropical vegetation of restinga of Rio de Janeiro State, Brazil. Leaves of Clusia lanceolata host up to 20 spheroid galls and show variation in their shape. We aimed to evaluate the effect of gall's intensity on leaves of Clusia lanceolata, and the extension of gall's impact on adjacent non-galled leaves. We analyzed the effect of the number of galls on leaf area, biomass, specific area and leaf appearance from 509 leaves of 14 individual plants. The results showed that differences of individual plants, pairs of leaves, and gall presence were responsible for more then 90 percent of variation on infested leaves. Variation on parasitic intensity level created differences in leaf response. Under moderate gall attack characterized by scattered galls on a leaf, the increase of the number of galls caused an increase of leaf biomass and area, and a decrease of specific area. The specific area was smaller also under high attack intensity, characterized by coalescent galls on a leaf. In those cases of extremely high parasitic intensity, galled leaves became deformed and the surface area was severely reduced. Leaf deformation due to gall attack led to early leaf abscission, indicated by the 90 percent of deformed leaves found in the youngest leaf pair of the branch. There was insufficient evidence that the impact of galls on leaf morpho-physiological parameters extended beyond the attacked leaves, because ungalled leaves did not change significantly when their opposite leaf had been galled.

O inseto galhador Clusiamyia nitida, 1996 (Diptera, Cecidomyiidae) freqüentemente infesta o arbusto Clusia lanceolata (Camb.) (Clusiaceae) na vegetação Neotropical de restinga do Estado do Rio de Janeiro. As folhas de Clusia lanceolata hospedam até 20 galhas esferóides e apresentam variações em sua forma. Buscamos avaliar o efeito da intensidade de galhas nas folhas de Clusia lanceolata, e a extensão do impacto de galhas em folhas adjacentes não-galhadas. Analisamos o efeito do número de galhas sobre a área foliar, biomassa, área específica e aparência foliar de 509 folhas de 14 indivíduos. Os resultados indicaram que diferenças individuais entre plantas, nos pares de folhas e na presença de galhas, foram responsáveis por mais de 90 por cento de variação entre folhas infestadas. A variação na intensidade de parasitismo criou diferenças de resposta foliar. Sob ataque moderado, caracterizado pela presença de galhas esparsas nas folhas, o aumento do número de galhas provocou o aumento de biomassa e área foliar e a diminuição da área específica. A área específica também foi menor sob ataque de alta intensidade, caracterizado por galhas unidas. Nos casos de parasitismo extremo, as folhas galhadas tornaram-se deformadas, apresentando a superfície foliar severamente reduzida. A deformação das folhas geradas pela presença de galhas provocou abscisão precoce, indicada pelos 90 por cento de folhas deformadas encontradas apenas nos pares mais jovens de folhas. Não houve evidencias suficientes que indicassem o impacto das galhas em parâmetros morfo-fisiológicos além das folhas atacadas, já que folhas não galhadas não sofreram alterações quando opostas a folhas galhadas.

Flavonoids, benzophenones and a new euphane derivative from Clusia columnaris Engl / Flavonóides, benzofenonas e um novo eufano de Clusia columnaris Engl

The polyisoprenylated benzophenones machuone and clusiachromene A have been isolated from the fruits of Clusia columnaris. The hexane extract of the young branches with leaves afforded a new euphane derivative, whose structure was elucidated by spectroscopic methods. On the contrary, the most polar EtOAc and ButOH extracts were constituted of flavonoid C-glucosides (isovitexin, vitexin and vitexin-2"-xyloside) and seven biflavonoids of the so-called Garcinia group.

Dos frutos de Clusia columnaris foram isoladas as benzofenonas poliisopreniladas machuona e clusiacromeno A. Do extrato em hexano obtido de galhos e folhas novas, um novo triterpeno do tipo eufano foi isolado. Sua estrutura foi elucidada através de métodos espectroscópicos. Por outro lado, dos extratos mais polares - em acetato de etila e em butanol, foram isolados os flavonóides C-glicosilados isovitexina, vitexina e vitexina-2"-xilosídeo, além de sete bisflavonóides conhecidos como bisflavonóides do grupo da Garcinia.

Bees visitors of three species of Clusia (Clusiaceae) flowers in Central Amazonia

Observations on bees visitors to three species of Clusia (Clusiaceae) flowers in the Reserva Adolpho Ducke, Manaus, Amazonas, Brazil were made during three two-week periods. The three species of Clusia, namely C. grandiflora, C. panapanari and C. insignis, presented variations regarding the species of bee visitors. A total of 23 bee species visited the three species of Clusia. The Euglossini and Meliponinae bees were the most frequent visitors of the Clusia flowers. Bee collecting behavior of floral resources is described.

Durante seis semanas foram realizadas observações das abelhas visitantes de flores de três espécies de Clusia (Clusiaceae), na Reserva Florestal Adolpho Ducke, em Manaus. As três espécies de Clusia: C. grandiflora Splitg., C. panapanari (Aubl.) e C. insignis Mart. apresentaram diferenças com relação às visitas de espécies de abelhas, tendo sido visitadas por 23 espécies. Abelhas Euglossini e Meliponinae foram os visitantes mais freqüentes em flores de Clusia. O comportamento de coleta de recursos florais é descrito.

Efecto de las micorrizas arbusculares sobre el crecimiento y supervivencia de dos especies nativas de la gran sabana, al transplantarlas a un área degradada / Effect of arbuscular mycorrhizas on growth and survival of two plant species indigenous of la gran sabana, transplanted to a degraded area

El propósito de este trabajo fue determinar si la inoculación con hongos micorrízicos arbusculares produce un aumento en el crecimiento y la supervivencia de dos arbustos nativos de La Gran Sabana, al ser transplantados a un área degradada. Semillas pre-germinadas de Clusia pusilla (Clusiaceae) y Gongylolepis benthamiana (Asteraceae) fueron sometidas a dos tratamientos durante una etapa de vivero que se extendió por 5 meses. Dichos tratamientos fueron: M: inoculación con el hongo micorrízico arbuscular Glomus manihotis, junto con la adición de 20 kg.ha-1 de superfosfato triple (SFT) y F: fertilización con 100 kg.ha-1 de SFT. Al final de la etapa de vivero, las plántulas fueron transplantadas a un área afectada por la remoción de la capa superficial del suelo en Luepa, La Gran Sabana. Los resultados obtenidos muestran un comportamiento contrastante entre ambas especies. La inoculación con micorrizas (tratamiento M) produjo un aumento significativo en la supervivencia de C. pusilla, en comparación con el tratamiento donde únicamente se aplicó el fertilizante (tratamiento F). En contraste, la supervivencia de G. benthamiana no se vio afectada por la inoculación con micorrizas. Ambas especies difieren en el tamaño de sus semillas, área foliar específica y relación vástago raíz, aunque son similares en cuanto a la densidad de pelos radicales y el diámetro de sus raíces. Se concluye que C. pusilla es mucho más dependiente de las micorrizas que G. benthamiana y se propone que esa mayor dependencia está relacionada con el menor tamaño de sus semillas en comparación con las de G. benthamiana.

The aim of this work is to evaluate the effect of arbuscular mycorrhizal inoculation on the growth and survival of two species of shrub indigenous of La Gran Sabana, when were transplanted to a degraded area. Pre-germinated seeds of Clusia pusilla (Clusiaceae) and Gongylolepis benthamiana (Asteraceae) were subjected to two different treatments during 5 months in the nursery, before transplanting to the field: F: fertilized with 100 kg.ha-1 of triple superphosphate (TSP) and M: inoculated with the arbuscular mycorrhizal fungus Glomus manihotis, plus 20 kg.ha-1 of TSP. At the end of the nursery stage, seedlings were transplanted to a degraded area situated at Luepa, in La Gran Sabana. Results were contrasting between both species. Arbuscular mycorrhizal inoculation of C. pusilla (M treatment) increased significantly its survival in comparison with treatment F. In contrast, no effect was observed on the survival of G. benthamiana, after AM-inoculation. Both species are different regarding seed weight; specific leaf area and shoot/root relationship but they have no differences respect to hair root density or root diameter. We concluded that C. pusilla is more dependent on mycorrhizas for survival than G. benthamiana. We hypothesized that the higher mycorrhizal dependence showed by C. pusilla is attributable to its smaller seeds in comparison with those of G. benthamiana.

Habitat use by Oryzomys subflavus (Rodentia) in an open shrubland formation in Restinga de Jurubatiba National Park, RJ, Brazil

The Restinga de Jurubatiba has at least 10 plant formations, including open Clusia shrubland. This formation is composed of dense shrubs of many shapes and sizes, where Clusia hilariana is one of the most important plant species. Shrublands with Clusia (CC) are poorer in plant species and less dense than shrublands without Clusia (SC). Oryzomys subflavus (Rodentia) is the most abundant small mammal species in the open Clusia shrubland. We tested the hypothesis that the abundance of rodents would increase with the size of the patch and would be higher in SC shrublands. Rodents were captured, marked and released in three 780-m-long transects. At each capture site, we evaluated the shape of the shrubland patch, calculated the area and noted the category of the shrubland. Using ANCOVA, we ascertained whether the abundance of Oryzomys subflavus increased with the sampled area and used CC and SC shrublands differently. We also verified if the size of patches used by rodents varies in the same frequency as the size of available shrublands. Rodent abundance was found to increase significantly with the area. There were no differences in the size of the patches used by rodents and the frequency of the size of available patches. This finding indicates that O. subflavus, in the study area, is a generalist species that uses its habitat according to availability.

A Restinga de Jurubatiba possui pelo menos 10 formações vegetais, entre elas a Arbustiva Aberta de Clusia. Esta formação é constituída por moitas densas de várias formas e tamanhos, sendo a espécie Clusia hilariana uma das mais importantes. Moitas com Clusia (CC) têm menor riqueza vegetal e são menos densas que moitas sem Clusia (SC). Oryzomys subflavus (Rodentia) é a espécie mais abundante de pequeno mamífero na Arbustiva Aberta de Clusia. Nós testamos a hipótese que a abundância do roedor aumentaria com o tamanho da área da moita e seria maior em moitas SC. Os roedores foram capturados, marcados e soltos em três transectos de 780 metros de extensão. Em cada ponto de armadilhamento, nós avaliamos a forma da moita, calculamos sua área e anotamos se era uma moita CC ou SC. Nós testamos por ANCOVA, se a abundância de O. subflavus aumentava com a área amostrada e se diferenciava em moitas CC ou SC. Nós também testamos se o tamanho das moitas usadas pelos roedores variavam na mesma freqüência que o tamanho de moitas disponíveis. A abundância do roedor aumentou com o aumento da área, mas as retas de regressão das moitas CC e SC não diferiram nem na inclinação e nem na elevação. O padrão na abundância de O. subflavus em diferentes classes de tamanho de moitas não diferiu do número disponível de moitas observadas por classes. Esses resultados indicam que O. subflavus é uma espécie generalista na área estudada, usando o hábitat de acordo com o que está disponível.

Patterns of leaf epicuticular waxes in species of Clusia: taxonomical implications

El género Clusia L. (Clusiaceae) comprende unas 300 especies que ocurren desde México y el sur de EEUU hasta Bolivia y el sur de Brasil. Entre ellas se incluyen árboles y arbustos, hemiepifitas, epifitas y lianas. El análisis taxonómico del género se dificulta por la pobre preservación de las flores al ser secadas. Este trabajo explora la composición de ceras epicuticulares para caracterizar especies mediante marcadores químicos. Se analizó la composición del extracto obtenido de seis especies mediante lavado de la superficie foliar con hexano. Las especies pudieron separarse en base a la proporción de alcanos, >90% del total en Clusia rosea, C. orthoneura y C. minor, a la presencia de los triterpenos a-amirina y lupeol en C. multiflora, y de friedelina y taraxerol, conjuntamente con C33 y C35 en C. grandiflora y C. schomburgkiana. Los resultados sugieren que la proporción de alcanos y triterpenoides de ceras epicuticulares tiene importancia taxonómica y puede ser utilizada para separar especies o secciones infragenéricas.

The genus Clusia L. (Clusiaceae) encompasses ca. 300 species and occurs from southern USA and Mexico, to southern Brazil and Bolivia. It includes free-standing trees and shrubs, hemiepiphytes, epiphytes, and lianas. Taxonomic analysis of this genus is difficult because of the poor preservation of floral material after drying. This work explores the composition of epicuticular waxes in order to allow characterization, at the species level, using chemical markers. The six species analyzed could be separated using the relative quantity of hexane-soluble compounds extractable from the leaf surface, which amount to >90% in Clusia rosea, C. orthoneura, and C. minor, the presence of the triterpenes a-amyrin and lupeol in C. multiflora, and of friedelin and taraxerol, together with C33 and C35, in C. grandiflora and C. schomburgkiana. The results suggest that the relative proportions of alkanes and triterpenoids in epicuticular waxes may have taxonomic significance for separating species or infrageneric sections.

O gênero Clusia L. (Clusiaceae) compreende umas 300 espécies que ocorrem desde México e o sul dos EE.UU. até Bolívia e o sul do Brasil. Entre elas se incluem árvores e arbustos, hemiepífitas, epífitas e lianas. A análise taxonômica do gênero se dificulta pela pobre preservação das flores ao ser secadas. Este trabalho explora a composição de ceras epicuticulares para caracterizar espécies mediante marcadores químicos. Se analisou a composição do extrato obtido de seis espécies mediante lavado da superfície foliar com hexano. As espécies puderam separar-se em base à proporção de alcanos, >90% do total em Clusia rosea, C. orthoneura e C. minor, à presença dos triterpenos a-amirina e lupeol em C. multiflora, e de friedelina e taraxerol, conjuntamente com C33 e C35 em C. grandiflora e C. schomburgkiana. Os resultados sugerem que a proporção de alcanos e triterpenóides de ceras epicuticulares tem importância taxonômica e pode ser utilizada para separar espécies ou seções infragenéricas.

A one-year study on carbon, water and nutrient relationships in a tropical C3 -CAM hemi-epiphyte, Clusia uvitana Pittier.

Diel (24 h) courses of CO2 and water-vapour exchange of leaves of hemi-epiphytic plants of Clusia uvitana Pittier (Clusiaceae) were measured under natural tropical conditions in the semi-evergreen moist forest of Barro Colorado Island, Panama, from January 1991 until January 1992. Plants were studied at two sites, in the crown of a 47-m tall tree (Ceiba pentandra) and on the shore of Lake Gatun, at a height of about 2-4 m. The following results were obtained: (1) Diel carbon gain was mainly a function of photosynthetic photon fluence rate (PPFR) on individual days. PPFR also strongly affected CAM activity. A leafless period of the host tree Ceiba pentandra resulted in higher incident PPFRs and slightly lower nighttime temperatures in the canopy of C uvitana; this led to increases in both daytime and nighttime CO2 fixation. (2) In fully mature sun leaves from the two sites, nocturnal net uptake of atmospheric CO2 occurred on almost all of the 71 days measured and nocturnal carbon gain was enhanced during the dry season. (3) In C. uvitana at the Lake site, 24-h carbon gain during the wet and dry season was similar to C. uvitana at the Ceiba site during the leafless period of the host tree. Overall CAM activity was lower at the Lake site. (4) Recycling of respiratory CO2 was a major route for nocturnal acid synthesis. Nocturnal net uptake of atmospheric CO2 was closely correlated with changes in titratable acidity, but accounted for only about 30% of the nocturnal increase in organic acids. (5) Mature shade leaves performed CAM only during the dry season, whereas in the wet season they showed atmospheric CO2 uptake exclusively in the light. (6) Independent of exposure or season, leaves less than about 12 wk old showed a C3 pattern of diel gas exchange and the level of titratable acidity was high day and night. (7) The annual carbon budget of outer canopy leaves of C uvitana in the Ceiba site was 1780 g CO2 m-2 a-1 and the average long-term water-use efficiency was 23 × 10-3 g CO2 g-1 H2 O. (8) Vegetative growth was strongly seasonal. Branch length increment and leaf area development was much higher in the wet season. Mineral element contents in these evergreen plants showed no age-related changes, but a significant proportion of elements was retrieved before abscission.

Hydraulic architecture, water relations and vulnerability to cavitation of Clusia uvitana Pittier: a C3 -CAM tropical hemiepiphyte.

Clusia uvitana Pittíer (Clusiacea) is a tropical hemiepiphyte that has been shown to display a high plasticity in the expression of CAM in response to the environment. When water is available CO2 is taken up mostly during the- day. This study of the water relations and hydraulic architecture has revealed that leaf water potentials, £ ranged from 0-7 to -0.9 MPa and changed very little with time or water availability. The absolute hydraulic conductivity of stem segments (K,) and the specific conductivity (K1 ) were comparable to many other temperate and tropical species, but the leaf specificity conductivity (K1 ) was 1/3 to 1/30 that of many other species. So stems supported high leaf areas per unit of hydraulic conductivity. C uvitana was very vulnerable to cavitation, reaching 50 % loss of hydraulic conductivity at stem £=1.3 MPa. The species survives in spite of low K1 and high xylem vulnerability, because the CAM physiology insures low transpiration rates and high ability to evade dehydration.