Arbuscular mycorrhizal fungi activity in the rhizosphere of tree seedlings subjected to residual herbicides / Atividade de fungos micorrízicos arbusculares na rizosfera de mudas de árvores submetidas a herbicidas residuais

Trees occurring on the margins of agricultural areas can mitigate damage from residual herbicides. Rhizospheric microbial activity associated with trees is one of the main remedial capacity indicators. The objective of this study was to evaluate the rhizospheric microbiological activity in tree species subjected to the herbicides atrazine and sulfentrazone via the rhizosphere. The experiment was designed in four blocks and a 6 × 3 factorial scheme. The first factor consisted of six tree species from Brazil and the second of atrazine, sulfentrazone, and water solutions. Four herbicide applications were performed via irrigation. The total dry mass of the plants, mycorrhizal colonization, number of spores, basal respiration of the rhizospheric soil, and survival rate of bioindicator plants after phytoremediation were determined. Trichilia hirta had higher biomass when treated with atrazine and sulfentrazone. Herbicides decreased the microbial activity in Triplaris americana and did not affect the microbiological indicators of Myrsine gardneriana, Schizolobium parahyba, and Toona ciliata. Fewer bioindicator plants survived in soil with Triplaris americana and sulfentrazone. Microbiological indicators were influenced in different ways between species by the presence of herbicides in the rhizosphere.

As árvores que ocorrem nas margens das áreas agrícolas podem mitigar os danos dos herbicidas residuais. A atividade microbiana rizosférica associada às árvores é um dos principais indicadores de capacidade corretiva. O objetivo deste trabalho foi avaliar a atividade microbiológica rizosférica em espécies arbóreas submetidas aos herbicidas atrazina e sulfentrazone via rizosfera. O experimento foi estruturado em quatro blocos e esquema fatorial 6 × 3. O primeiro fator consistiu em seis espécies de árvores do Brasil e o segundo em soluções de atrazine, sulfentrazone e água. Quatro aplicações de herbicidas foram realizadas via irrigação. Foram determinados a massa seca total das plantas, colonização micorrízica, número de esporos, respiração basal do solo rizosférico e taxa de sobrevivência de plantas bioindicadoras após fitorremediação. Trichilia hirta apresentou maior biomassa quando tratada com atrazina e sulfentrazone. Os herbicidas diminuíram a atividade microbiana em Triplaris americana e não afetaram os indicadores microbiológicos de Myrsine gardneriana, Schizolobium parahyba e Toona ciliata. Menos plantas bioindicadoras sobreviveram no solo com Triplaris americana e sulfentrazone. Os indicadores microbiológicos foram influenciados de formas distintas entre as espécies pela presença dos herbicidas na rizosfera.

Biometric assessment of early stem growth at a commercial stand of African mahogany (Khaya grandifoliola)

African mahogany species (Khaya spp.) have proven to be promising in the Brazilian forestry scenario, replacing native mahogany owing to their medium-fast growth and relevant timber value. This study aimed to carry out forest inventory and assessments of a Khaya grandifoliola plantation in the first years after planting, test hypsometric models to describe tree growth, and identify the maximum commercial stem yield (i.e., greater than 6 m in height). The stand was located in the municipality of Piracanjuba (GO), where seedlings of seed origin were used. Twenty random plots with a 15 m radius were allocated, and the total height (HT), stem height (HS), diameter at breast height (DBH), crown area, and forest canopy were measured. Four hypsometric models were employed in this study. The best equation was selected based on determination coefficients and standard errors. Further, the models were cross-validated to evaluate predictability and bias. At four years of planting, the largest class of HS was found to range from 3.1 to 4.1 m, and most trees had a DBH ranging from 0.084 to 0.126 m. The percentage of trees with stems > 6 m was 8.35%. The linear model ensured more consistent results for estimating HT, while the quadratic and Weibull models led to more consistent results for HS. By using models, stem measurements can be measured based on DBH, ultimately aiding the selection of stem management strategies for the growth of forests with greater commercial value.

Wastewater from swine farming in the growth and nutrition of Khaya senegalensis (DESR. ) A Juss seedlings / Água residuária da suinocultura no crescimento e nutrição de mudas de khaya senegalensis (DESR. ) a juss

This study evaluated the use of wastewater from swine farming in the growth and nutritional balance of Khaya senegalensis (Desr.) A. Juss. (African mahogany) seedlings. The experiment was setup in a shade house on the Professor Cinobelina Elvas Campus of the Federal University of Piauí, in Bom Jesus, in the State of Piauí, Brazil. The experimental design was completely randomised, with five concentrations of swine farm wastewater (SFW) (0, 25, 50, 75 and 100%) added to the irrigation water. The growth and nutritional balance of the seedlings were evaluated 100 days after sowing, by measuring shoot height (H), stem diameter (SD), number of leaves (NL), total chlorophyll (TC), leaf area (LA), shoot dry weight (SDW) and root dry weight (RDW), and by calculating the total dry weight (TDW), leaf (LBA), stem (SBA), and root (RBA) biomass allocation, Dickson Quality Index (DQI) and average Nutritional Balance Index (NBIm). It was found that K. senegalensis seedlings responded to the SFW, showing the best results for growth and nutritional balance at concentrations of around 50%.

Este trabalho foi realizado com o objetivo de avaliar a utilização da água residuária da suinocultura no crescimento e no balanço nutricional de mudas de Khaya senegalensis (Desr.) A. Juss. (mogno-africano). O experimento foi instalado no Campus Profa. Cinobelina Elvas, Universidade Federal do Piauí, em Bom Jesus, PI, dentro de uma casa de sombra. O experimento foi implantado em delineamento inteiramentecasualizado, com cinco concentrações de água residuária de suinocultura (ARS) (0; 25; 50; 75 e 100%) na água de irrigação. O crescimento e balanço nutricional das mudas foram avaliados aos 100 dias após a semeadura, com a mensuração da altura da parte aérea (H), diâmetro do coleto (DC), número de folhas (NF), clorofila total (CT), área foliar (AF), massa seca da parte aérea (MSPA) e do sistema radicular (MSR) e calculadas a massa seca total (MST), as alocações de biomassa foliar (ABF), caule (ABC), raízes (ABR), o Índice de Qualidade de Dickson (IQD) e Índice de Balanço Nutricional médio (IBNm). Constatou-se que a as mudas de K. senegalensis responderam à ARS, apresentando os melhores resultados de crescimento e equilíbrio nutricional em concentrações em torno de 50%.

Do polyembryonic seeds of Carapa surinamensis (Meliaceae) have advantages for seedling development?

Polyembryony is the differentiation and development of multiple embryos in a single seed. This characteristic can provide advantages, as more than one embryo is produced with the same amount of resources, and the probability of establishment of at least one seedling increases. However, sibling seedlings may also increase competition, affecting development and survival. In the present study, the possible advantages and disadvantages of polyembryony were analyzed in the initial establishment of seedlings of Carapa surinamensis (Meliaceae), a tree species that produces monoembryonic or polyembryonic seeds. In this regard, the development of single seedlings was compared with a pair of seedlings emerging from polyembryonic seeds. We compared the development of seedlings attached to or detached from each other and to the seed resources. We observed two levels of competition: (a) for the seed reserves during germination and initial development, as multiple embryos of C. surinamensis share the same reserves, and (b) for external factors, mostly space for root and shoot development, and also for light. Reducing the competition for external factors by separating the siblings was not enough to reduce the effects of competition for seed reserves in the first six months of development. Nevertheless, viable seedlings were produced in all treatments. Thus, depending on sprout management in the nursery, the number of seedlings per seed can be significantly increased by detaching the seedlings, or more vigorous seedlings can be obtained when only one seedling is maintained.(AU)

Poliembrionia é a diferenciação e o desenvolvimento de múltiplos embriões em uma única semente. Esta característica pode proporcionar diversas vantagens, como aumentar o número de embriões produzidos com a mesma quantidade de recursos, e aumentar a probabilidade de estabelecimento de pelo menos uma plântula de uma única semente. Por outro lado, a competição entre plântulas pode aumentar, afetando seu desenvolvimento e sobrevivência. Neste estudo, foram analisadas as possíveis vantagens e desvantagens da poliembrionia em sementes de andiroba, Carapa surinamensis (Meliaceae), uma espécie arbórea que produz sementes monoembriônicas ou poliembriônicas. Comparamos o desenvolvimento de plântulas únicas com o de pares de plântulas provenientes de sementes poliembriônicas. As plântulas foram mantidas unidas ou separadas entre si e ligadas à ou destacadas da semente. Os resultados revelaram dois níveis de competição: (a) pelas reservas da semente durante a germinação e desenvolvimento inicial da plântula, quando embriões múltiplos de C. surinamensis compartilham as mesmas reservas, e (b) por fatores externos, principalmente espaço para o desenvolvimento da raiz e da parte aérea, e luz. A redução da competição por fatores externos, através da separação das plântulas, não foi suficiente para reduzir os efeitos da competição pelas reservas das sementes nos primeiros seis meses de desenvolvimento. Apesar disso, plântulas viáveis foram produzidas em todos os tratamentos. Assim, dependendo do manejo dos brotos em viveiro, o número de plântulas produzidas pode ser aumentado significativamente por meio da separação entre plântulas, ou o vigor das plântulas pode ser incrementado através de sua manutenção individualizada.(AU)

A comparative study of the thermal ranges of three germination criteria of a tropical tree with bioeconomic interest: Carapa surinamensis Miq. (Meliaceae) / Estudo comparativo sobre a variação térmica em três critérios de germinação de uma árvore tropical com interesse econômico: Carapa surinamensis Miq. (Meliaceae)

Abstract Species of the Carapa spp. complex, occurring in the Neotropics, Africa and India, have multiple uses, including timber, with the seed oil being used in phyto-pharmaceutical products and cosmetics. This study aimed to determine the thermal ranges of the germination process, comparing germination criteria used by seed physiologists and seed technologists, and to suggest recommendations for seed quality assessment. Germination was assessed at constant temperatures between 10 ─ 40 °C using three germination criteria: (1) radicle length ≥ 0.5 cm (physiological criterion); (2) epicotyl length ≥ 1 cm; and (3) epicotyl length ≥ 5 cm (criterion for seed quality tests). The base temperature was similar for the three criteria and ranged between 10 ─ 2 °C. The Maguire's Speed Index indicated 30 °C as most adequate. However, the upper temperature limit differed: for radicle protrusion it was above 40 ºC; and for both epicotyl lengths, it was between 35 ─ 40 °C. Seed coat removal accelerated the germination process of these recalcitrant seeds, and is recommended for seed quality assessment, which allows completion of the germination trial in approximately one month.

Resumo As espécies do complexo Carapa spp. ocorrem na região Neotropical, na África e na Índia, têm usos múltiplos, fornece madeira de valor comercial e o óleo extraído das sementes tem uso fitoterápico e cosmético. O objetivo deste trabalho foi determinar a faixa térmica tolerável do processo germinativo, comparando os critérios de germinação utilizados pelos fisiologistas e os tecnólogos de sementes, e sugerir recomendações para a avaliação da qualidade das sementes. A germinação foi avaliada em temperaturas constantes entre 10 e 40 °C utilizando três critérios de germinação: (1) formação da radícula ≥ 0,5 cm (critério fisiológico); (2) alongamento de epicótilo ≥ 1 cm; e (3) alongamento de epicótilo ≥ 5 cm (critério para testes de qualidade de sementes). A temperatura de base foi semelhante para os três critérios entre 10 e 12 °C. O índice de velocidade de Maguire indicou 30 °C como a temperatura mais adequada. O limite superior de temperatura diferiu entre os critérios, sendo acima de 40 ºC para protrusão da radícula e para ambos os alongamentos de epicótilo entre 35 e 40 °C. A remoção do tegumento de semente acelerou o processo de germinação dessas sementes recalcitrantes sendo recomendada para a avaliação da qualidade da semente, o que permite concluir o teste de germinação em aproximadamente um mês.

Chemical Composition and Antimicrobial Efficiency of Swietenia macrophylla Seed Extract on Clinical Wound Pathogens

Microbial wound infection prolonged the hospitalization and increase the cost for wound management. Silver is commonly used as antimicrobial wound dressing. However, it causes several adverse side effects. Hence, this study was aimed to evaluate the antimicrobial efficiency of Swietenia macrophylla seed extract on clinical wound pathogens. Besides, the bioactive constituents of the seed extract were also determined. S. macrophylla seeds were extracted with methanol by maceration method. The seed extract inhibited 5 test bacteria and 1 yeast on disc diffusion assay. The antibacterial activity was broad spectrum, as the extract inhibited both Gram positive and Gram negative bacteria. On kill curve analysis, the antibacterial activity of the seed extract was concentration-dependent, the increase of extract concentration resulted in more reduction of bacterial growth. The extract also caused 99.9% growth reduction of Bacillus subtilis relative to control. A total of 21 compounds were detected in gas chromatography-mass spectrometry analysis. The predominant compounds present in the extract were oleic acid (18.56%) and linoleic acid (17.72%). In conclusion, the methanolic extract of S. macrophylla seeds exhibited significant antimicrobial activity on clinical wound pathogens. Further investigations should be conducted to purify other bioactive compounds from the seeds of S. macrophylla.

Healing effect of andiroba-based emulsion in cutaneous wound healing via modulation of inflammation and transforming growth factor beta 3

Abstract Purpose: To evaluate the effects and mechanisms of andiroba-based emulsion (ABE) topical treatment on full-thickness cutaneous wounds in rats. Methods: The wounds were harvested on days 3, 7, 15, and 20 post-surgery. Wound contraction rate, quantitative immunohistochemistry [macrophages, myofibroblasts, capillaries, collagens (col) I and III, transforming growth factor β3β (TGFβ3)], and tensile strength were assessed. Results: Treated wounds were smaller, contracted earlier and had increased angiogenesis, fewer CD68+ and M2 macrophages on days 7 and 15, but higher on day 20. Myofibroblasts appeared on days 3 to 7 in untreated wounds and on days 7 to 15 in treated wounds. TGFβ3 levels were higher in the treated wounds, less dense collagen fibers, lower col I/III ratios and a higher tensile strength. Conclusion: These results demonstrate the important anti-inflammatory role of treatment and the associated modulation of macrophages, myofibroblasts, and TGFβ3 levels. Collagen fibers in the treated wounds were more organized and less dense, similar to unwounded skin, which likely contributed to the higher tensile strength.

Conidial fungi associated with leaf litter of red cedar (Cedrela odorata) in Belém, Pará (eastern Brazilian Amazon) / Fungos conidiais associados com o folhedo de cedro vermelho (Cedrela odorata) em Belém, Pará (Amazônia Oriental brasileira)

The aim of this study was to investigate the species of conidial fungi associated with leaf litter of Cedrela odorata (Meliaceae), an endangered red cedar species typical of Amazonian terra-firme forests. Conidial fungi were sampled around C. odorata individuals in three forest areas in the municipality of Belém (Pará State, Brazil). A total of 104 species were identified, with 53 new records for the state of Pará, 46 first records for the Brazilian Amazon, including new records for Brazil (Cordana abramovii), for South America (Acarocybiopsis cubitaensis, Xylocladium claviforme) and for the Americas (Dactylaria biguttulata). A review of species of conidial fungi reported on C. odorata is provided, indicating its distribution in Brazil. For each new record in Brazil, South America and the Americas we present a description, illustrations, geographical distribution and taxonomic comments.

O objetivo deste estudo foi investigar as espécies de fungos conidiais associadas com o folhedo de Cedrela odorata, uma espécie de cedro vermelho ameaçada, típica de florestas de terra firme da Amazônia. Fungos conidiais foram amostrados no folhedo ao redor de indivíduos de C. odorata em três áreas florestais no município de Belém (PA). Um total de 104 espécies foi identificado, com 53 novos registros para o Estado do Pará e 46 que representam o primeiro registro para a Amazônia brasileira. Dentre estas, foram encontrados novos registros para o Brasil (Cordana abramovii), para a América do Sul (Acarocybiopsis cubitaensis, Xylocladium claviforme) e para as Américas (Dactylaria biguttulata). Uma revisão das espécies de fungos conidiais relatadas em C. odorata é fornecida, indicando sua distribuição no Brasil. Para cada novo registro no Brasil, América do Sul e Américas apresentamos uma descrição, ilustrações, distribuição geográfica e comentários taxonômicos.

Primera descripción de Sclerotium coffeicola en caoba africana en México / First description of Sclerotium coffeicola on African mahogany in Mexico

Una enfermedad foliar fue detectada en la plantación comercial de Khaya senegalensis con 3 anos de edad, en la localidad de Huimanguillo (Tabasco, México). Mediante la caracterización morfológica y molecular, y por el cumplimiento de los postulados de Koch, se determinó que el agente causal corresponde al hongo Sclerotium coffeicola. Este es el primer reporte de S. coffeicola causando mancha foliar en caoba africana en México.

A foliar disease was detected in the commercial plantation of Khaya senegalen with three years of age in Huimanguillo, Tabasco, Mexico. Through the morphological and molecular characterization and the compliance of the Koch's postulates, it was concluded that the causal agent corresponds to the fungus Sclerotium coffeicola. This is the first report of S. coffeicola causing leaf spot on African mahogany in Mexico.

Phenology of Guarea macrophylla Vahl (Meliaceae) in subtropical riparian forest in southern Brazil / Fenologia de Guarea macrophylla Vahl (Meliaceae) em mata ciliar subtropical no sul do Brasil

Abstract Climate is one of the main factors that affect plant behavior. The phenology of Guarea macrophylla Vahl, which is a small tree used for reforestation of degraded areas, was monitored for 18 months in a riparian forest at the Schmidt Stream, Campo Bom, in the state of Rio Grande do Sul, southern Brazil. Vegetative (leaf fall and leaf flushing) and reproductive events were observed, with the latter divided into flowering (flower buds and anthesis) and fruiting (unripe, ripening and ripe fruit). Phenological events were related to temperature, photoperiod and precipitation and their seasonality was verified by circular statistical analysis. Vegetative phenophases were continuous; they were not related to climate factors and presented low intensity, emphasizing the perennial aspect of the species. Flowering occurred during spring and summer. Both flower buds and anthesis were related to temperature and photoperiod. Fruiting was constant and went through all stages of development. Unripe fruits developed during the months with the lowest photoperiod and ripen more intensely in winter, on colder days. Ripe fruit became available for dispersal in spring, in times of longer photoperiod and higher temperatures. Except for leaf fall, all other phenological events showed seasonality in their manifestation. The one-month difference between the onsets of the flowering phases observed in this study indicated that local climate changes induced the early occurrence of this phenophase.

Resumo O clima é um dos principais fatores que condicionam o comportamento das plantas. A fenologia de Guarea macrophylla Vahl, arvoreta utilizada no reflorestamento de áreas degradadas, foi acompanhada durante 18 meses, em mata ciliar do arroio Schmidt, Campo Bom, RS, Brasil. Foram observados os eventos vegetativos (queda foliar e brotamento) e reprodutivos, separados em floração (botão floral e antese) e frutificação (frutos imaturos, maturando e maduros). Os eventos fenológicos foram relacionados à temperatura, ao fotoperíodo e à precipitação e a sua sazonalidade foi verificada por meio da análise estatística circular. As fenofases vegetativas foram contínuas, não se relacionaram com os fatores climáticos e apresentaram baixa intensidade, ressaltando a característica perene da espécie. A floração ocorreu durante a primavera e o verão e tanto botão floral quanto antese relacionaram-se com temperatura e fotoperíodo. A frutificação foi constante e passou por todos os estádios de desenvolvimento. Os frutos imaturos desenvolveram-se em meses com o menor fotoperíodo e maturaram mais intensamente no inverno, em dias de menor temperatura. Os frutos maduros tornaram-se disponíveis para os dispersores na primavera, em períodos com maior fotoperíodo e temperatura. Com exceção da queda foliar, todos os outros eventos fenológicos apresentaram sazonalidade em sua manifestação. O adiantamento de um mês entre as florações observadas no presente estudo indicou que as alterações climáticas locais de temperatura induziram a ocorrência antecipada dessa fenofase.

Chemical composition, antimicrobial and antioxidant potential of the essential oil of Guarea kunthiana A. Juss / Composição química, potencial antimicrobiano e antioxidante do óleo essencial de Guarea kunthiana A. Juss

Abstract The essential oils are extracted from plant compounds and can present activities antimicrobial and antioxidant properties. The goals of the present study were: (a) to determine the chemical composition of the essential oil of Guarea kunthiana A. Juss using the method of gas chromatography coupled to mass spectrometry (GC-MS); (b) to evaluate the antimicrobial potential of this oil using the broth microdilution method against different microorganisms: five Gram-negative bacteria, four Gram-positive bacteria and a yeast and (c) to determine the antioxidant activity of the oil using the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical assay. The GC-MS analyses allowed identifying 13 constituents, representing 96.52% of the essencial oil composition. The main compounds identified were α-zingiberene (34.48%), β-sesquiphellandrene (22.90%), and α-curcumene (16.17%). With respect to the antimicrobial activity, the essential oil was effective against all the microorganisms tested, except for the bacteria E. coli and K. pneumoniae, which were resistant to the action of the oil. From a general point of view, Gram-positive bacteria were more susceptible to the action of the essential oil than Gram-negative bacteria. The essential oil exhibited antioxidant potential.

Resumo Os óleos essenciais são compostos extraídos de plantas e podem apresentar propriedades antimicrobianas e antioxidantes. O objetivo deste trabalho foi (a) determinar a composição química do óleo essencial de Guarea kunthiana A. Juss pelo método de cromatografia gasosa acoplada à espectrometria de massas (CG-EM); (b) avaliar o potencial antimicrobiano deste óleo pelo método de microdiluição em caldo frente a diferentes micro-organismos, sendo cinco bactérias Gram-negativas, quatro Gram-positivas uma levedura e (c) por fim, determinar a atividade antioxidante do óleo pelo método de captura do radical livre 2,2-difenil-1-picril hidrazil (DPPH). As análises de CG-EM resultaram na identificação de 13 constituintes, representando 96,52% da composição do óleo essencial. Os principais compostos identificados foram α-Zingibereno (34,48%), β-Sesquifelandreno (22,90%) e α-Curcumeno (16,17%). Em relação à atividade antimicrobiana, o óleo essencial foi efetivo frente a todos os micro-organismos testados exceto para as bactérias E. coli e K. pneumoniae, as quais se apresentaram resistentes à ação do óleo. Em geral, as bactérias Gram-positivas foram mais suscetíveis à ação do óleo essencial em relação às Gram-negativas. O óleo essencial apresentou potencial.

Antigenotoxicity protection of Carapa guianensis oil against mitomycin C and cyclophosphamide in mouse bone marrow

ABSTRACT The aim of this study was to evaluate the possible protective of C. guianensis oil against MMC and CP, which are direct- and indirect-acting chemical mutagens, using the micronucleus test. Three experiments were performed. First the C. guianensis oil was co-administered to mice at doses of 250, 500 and 1000 mg/kg bw with 4 mg/kg bw MMC or 50 mg/kg bw CP. Second, the mutagenic drug (CP) was administered ip 50 mg/kg bw and after 6 and 12 hours 250 and 500 mg/kg bw of C. guianensis oil were administered. In the last, C. guianensis oil was administrated (250 and 500 mg/kg bw) during five days and after it was administered ip 50 mg/kg bw CP. The results obtained showed that the C. guianensis oil is not cytotoxic neither genotoxic to mouse bone marrow. Regarding the antimutagenic effect, all doses of C. guianensis oil were significantly (p < 0.05) effective in reducing the frequency of micronucleated polychromatic erythrocytes, when compared with MMC or CP alone. Based on these results, our results suggest that the C. guianensis oil shows medicinal potential as an antimutagenic agent, modulating the mutagenicity caused by both direct- and indirect-acting chemical mutagens, in a mammalian model.

Acute oral toxicity from a fraction rich in phenolic compounds from the leaf extract of Swietenia macrophylla king in a murine model / Determinación de la toxicidad aguda oral de una fracción rica en compuestos fenólicos del extracto de hojas Swietenia macrophylla king en un modelo murino

Background: The mahogany tree (Swietenia macrophylla King) is widely used in traditional medicine, especially its seeds, which are used in Malaysia, Indonesia and some countries of South America. Recently an active fraction of the leaf ethanolic extract (labelled "Sm13-16,23"), showed promising results against some toxins of South American pit vipers. Objectives: In this study the aim was to evaluate the acute oral toxicity of fraction Sm13-16,23 from the leaf ethanolic extract, using Swiss Webster mice. Methods: Fraction Sm13-16,23 was administered orally in a single dose to 2000 mg/kg and 300 mg/kg, clinical follow-up for 14 days was performed and then euthanasia, necropsy and histopathology of organs were performed. Results: Overall, there were not deaths recorded during the study period. Further not signs of toxicity in doses of 300mg/kg were observed, but at doses of 2000 mg/kg, histopathological lesions in the liver, as karyomegaly and binucleation were observed. Conclusions: Fraction Sm13-16, 23 does not produce toxicity lesion at doses of 300mg/kg, indicating that the acute oral toxicity risk is low.

Antecedentes: El árbol de la caoba (Swietenia macrophylla King) es utilizado ampliamente en la medicina tradicional, especialmente sus semillas, que son usadas en Malasia, Indonesia y algunos países de Suramérica. Recientemente una fracción activa del extracto etanólico de las hojas (llamada "Sm13-16,23"), demostró resultados promisorios frente algunas toxinas de las víboras suramericanas. Objetivos: En este estudio se evaluó la toxicidad aguda oral de la fracción Sm13-16,23 del extracto etanólico de las hojas de S. macrophylla utilizando ratones Swiss Webster. Métodos: La fracción Sm13-16,23 se administró vía oral como dosis única a 2000 mg/kg y 300 mg/kg, se realizó seguimiento clínico de los animales durante 14 días y finalmente se les aplicó la eutanasia. Se practicó la necropsia de cada animal y se tomaron algunos órganos para su evaluación histopatológica. Resultados: No se registraron muertes durante el tiempo de estudio, ni se evidenciaron signos de toxicidad a dosis de 300mg/kg, sin embargo, a la dosis de 2000 mg/kg, se encontraron lesiones histopatológicas en el hígado; como cariomegalia y binucleación de los hepatocitos. Conclusión: La fracción Sm13-16,23 no produjo lesiones de toxicidad a dosis de 300mg/ kg, lo que indicia que el riesgo de toxicidad aguda oral es bajo.

Cytotoxicity and Structure Activity Relationship of Dammarane-Type Triterpenoids from the Bark of Aglaia elliptica against P-388 Murine Leukemia Cells

Six dammarane-type triterpenoids, dammar-24-en-3β-ol (1), 3β-epicabraleahydroxy lactone (2), (E)-25-hydroperoxydammar-23-en-3β,20-diol (3), dammar-24-en-3β,20-diol (4), 3β-acetyl-20S,24S-epoxy-25-hydroxydammarane (5), and 3β-epiocotillol (6) were isolated from the methanolic extract of the bark of Aglaia elliptica. The chemical structure were identified on the basis of spectroscopic evidence and by comparison with those spectra previously reported. Compounds 1 – 6 were isolated first time from this plant. Compounds 1 – 6, along with a known synthetic analog, cabraleone (7) were evaluated their cytotoxic activity against P-388 murine leukimia cells in vitro. Among those compounds 3β-acetyl-20S,24S-epoxy-25-hydroxydammarane (5) showed strongest cytotoxic activity with IC₅₀ value of 8.02 ± 0.06 µM.

Two new phragmalin-type limonoids orthoesters from Entandrophragma candollei / 中国天然药物

Two new phragmalin-type limonoids orthoesters, encandollens A and B (1 and 2), were isolated from the stem barks of Entandrophragma candollei collected in Ghana. The structures of these compounds were elucidated on the basis of HR-ESI-MS, H and C NMR, HSQC, HMBC, and ROESY data. Compound 1 was a rare C-15 enolic acyl phragmalin-type limonoid orthoester. Compounds 1 and 2 exhibited weak inhibitory effects on NO production in lipopolysaccharide (LPS)-induced RAW 264.7 cells.

Seedling growth and survival of five tree species in secondary forests and adjacent pastures in the montane rain forests of Southern Costa Rica / Crecimiento y supervivencia de plántulas de cinco especies de árboles en bosques secundarios y pastizales adyacentes en un bosque lluvioso montano del sur de Costa Rica

Abstract:Successful forest restoration in tropical environments is limited by the paucity of studies on the initial establishment and early survival requirements of seedlings of most native tropical tree species under disturbed conditions. Here, we evaluated the initial growth responses and the regeneration potential of seedlings of five tree species native to Costa Rica (Hasseltia floribunda, Inga densiflora, Persea americana, Tapirira mexicana and Trichilia pittieri). Seedlings were grown in secondary forests and adjacent open pastures under contrasting conditions of light availability. We quantified seedling growth, survival and herbivory from August 2010 to August 2011 on a monthly basis, and measured differences in leaf mass per area (LMA) at the end of the experiment. We found significant variation in growth responses between the understory of secondary forests and pastures. Growth in height was highest in pastures across all species, with I. densiflora, P. americana and T. mexicana showing the most striking differences. In contrast, H. floribunda and T. pittieri did not show differences in diameter growth between environments. Except for T. mexicana, herbivory increased throughout the experiment in all the species. Herbivory increased faster in pastures for H. floribunda and T. pittieri and showed higher rates in the forest understory for I. densiflora and P. americana. Seedling survival showed significant differences for all species across environments. Survival of H. floribunda and I. densiflora was higher in secondary forests, whereas the other species showed higher survival in pastures. LMA showed higher values in the pastures across all species, showing that individuals exposed to high light conditions had great photosynthetic rate and great leaf construction capacity. Due to their rapid growth and high survival, I. densiflora and T. mexicana showed great potential to restore abandoned pastures and secondary forests. Increasing our knowledge on the response of seedlings under disturbed conditions in tropical ecosystems is critical for improving the restoration of altered environments by matching the ecological amplitude of native species with specific environmental conditions. Rev. Biol. Trop. 64 (4): 1565-1583. Epub 2016 December 01.

Resumen:La restauración exitosa del bosque en ambientes tropicales está limitada por la carencia de estudios sobre los requisitos de hábitat, el establecimiento inicial, y la sobrevivencia de las plántulas de la mayoría de las especies de árboles tropicales nativos. En este estudio, evaluamos las respuestas en el crecimiento inicial y el potencial de regeneración de las plántulas de cinco especies de árboles nativos de Costa Rica (Hasseltia floribunda, Inga densiflora, Persea americana, Tapirira mexicana y Trichilia pittieri). Sembramos las plántulas en bosques secundarios y en pastizales abiertos adyacentes con condiciones de luz contrastantes. Cuantificamos el crecimiento, la supervivencia y el daño por herbivoría de las plántulas de forma mensual entre agosto 2010 y agosto 2011, y medimos las diferencias en el la masa foliar por área de la hoja al final del experimento. Existió una variación significativa en el crecimiento de las plántulas expuestas a la sombra en los bosques secundarios y aquellas que crecieron en pastizales. El crecimiento en altura fue mayor en pastizales en todas las especies; I. densiflora, P. americana y T. mexicana mostraron la mayor diferencia entre ambientes. En con- traste, H. floribunda y T. pittieri no mostraron diferencias en el crecimiento del diámetro entre ambientes. Con la excepción de T. mexicana, todas las especies mostraron un aumento en herbivoría durante el estudio. En los pastizales, el incremento de la herbivoría fue más rápido en H. floribunda y T. pittieri, mientras que para I. densiflora y P. americana fue mayor en el bosque. La sobrevivencia de plántulas fue diferente entre ambientes para todas las especies. La sobrevivencia de H. floribunda e I. densiflora fue mayor en el bosque secundario, mientras que en las demás especies hubo mayor sobrevivencia de plántulas en los pastizales. La masa foliar por área fue mayor en las plántulas que crecieron en los pastizales que en bosque secundario para todas las especies, lo que sugiere que los individuos que crecieron en condiciones de alta incidencia de luz tuvieron mayor tasa fotosintética y mayor capacidad de construcción de la hoja. Debido al rápido crecimiento y alta supervivencia I. densiflora y T. mexicana tienen gran potencial para la restauración de bosques secundarios y pastizales abandonados. Generar información sobre la respuesta de plántulas creciendo en bosques secundarios y pastizales en regeneración es crítico para mejorar los procesos de restauración de ambientes alterados. La restauración de estos bosques depende de la correspondencia entre las condiciones específicas de hábitat y la plasticidad ecológica de las especies nativas.

Larvicidal efficacies of plants from Midwestern Brazil: melianodiol from Guarea kunthiana as a potential biopesticide against Aedes aegypti

A total of 36 ethanol extracts from different anatomical parts of 27 plant species (18 families), native to the Pantanal and Cerrado biomes in Midwest Brazil, was assessed for their effect against Aedes aegypti larvae, the vector of dengue, hemorrhagic dengue, Zika and chikungunya fevers. Only the extract obtained from seeds of Guarea kunthiana (Meliaceae) proved active (LC50 = 169.93 μg/mL). A bioassay-guided investigation of this extract led to the isolation and identification of melianodiol, a protolimonoid, as the active constituent (LC50 = 14.44 mg/mL). Meliantriol, which was also obtained from the bioactive fraction, was nevertheless devoid of any larval toxicity, even at the highest concentration tested (LC50 > 100.0 mg/mL). These results indicate that the larvicidal activity of melianodiol stems from the presence of the carbonyl moiety at C-3 in the 21,23-epoxy-21,24,25-trihydroxy-tirucall-7-ene-type skeleton. The structures of both protolimonoids were established on the basis of spectral methods (1H and 13C NMR and MS). This is the first report on the toxicity of melianodiol against Ae. aegypti larvae. Based on the results, melianodiol can be regarded as a potential candidate for use as an ecologically sound biocontrol agent for reducing the larval population of this vector.

Pollen morphology of Carapa species (Meliaceae) from the Brazilian Amazon / Morfologia polínica de Carapa (Meliaceae) espécies da Amazônia brasileira

The crabwood (Carapa) represents an important source of natural resources. The objective of this work was to study the pollen morphology of the three species of Carapa (Meliaceae) registered in the Brazilian Amazon. The pollen grains were obtained from floral buds, pistillate and staminate flowers of Carapa guianensis, C. surinamensis and C. vasquezii. In order to explore the taxonomic implications of the pollen study for these species of Carapa, lactic acetolysis method was used for light microscopy study. Furthermore, the non-acetolyzed material was used in the study of the scanning electron microscopy. It was found that the three Carapa species present little variations in pollen morphology. Compared to the other species this study, Carapa vasquezii has higher values for the length and width of endoaperture; however, it has lower values for polar and equatorial diameter, equatorial diameter in polar view and apocolpium side.

A andiroba (Carapa) representa uma importante fonte de recursos naturais. O objetivo deste trabalho foi estudar a morfologia polínica das três espécies de Carapa (Meliaceae) registradas na Amazônia brasileira. Os grãos de pólen foram obtidos de botões florais, flores pistiladas e estaminadas de Carapa guianensis, C. surinamensis e C. vasquezii. A fim de explorar as implicações taxonômicas do estudo de pólen para estas espécies de Carapa, o material foi preparado de acordo com o método de acetólise láctico, permitindo a utilização de estudos de microscopia de luz. Além disso, o material não-acetolisado foi utilizado no estudo da microscopia eletrônica de varredura. O estudo mostra que as três espécies de Carapa apresentam pequenas variações na morfologia polínica. Comparada com as outras espécies deste estudo, Carapa vasquezii têm valores mais elevados para o comprimento e largura da endoabertura, entretanto, tem valores inferiores para diâmetro polar, equatorial, diâmetro equatorial em vista polar e lado do apocolpo.

Characterization of the most promising fraction of Swietenia macrophylla active against myotoxic phospholipases A2: identification of catechin as one of the active compounds / Caracterización de la fracción más promisoria de Swietenia macrophylla activa contra fosfolipasas A2 miotoxicas: identificación de catequina como uno de los compuestos activos

Background: The pharmacological effects produced by snakebite accidents involve the actions of several enzymes, of which those of the phospholipases A2 (PLA2) exhibit a wide variety of effects such as edema and myotoxicity. Some plant extracts have been antagonists of crude snake venoms and toxins. Based on promising bioactivity, Swietenia macrophylla King was selected for further studies. Objective: The purpose of this study was to identify the PLA2 inhibitors present in the crude extract of S. macrophylla that could be promising leads in neutralizing the local effects of ophidian accidents. Methods: Bioassay-guided fractionation of the ethanolic extract of the leaves of S. macrophylla lead to the detection of (+)-catechin, characterized through gas chromatography coupled with mass spectrometry (GC-MS), and confirmed by HPLC. The PLA2 inhibitory activity was measured with the Dole method and a spectrophotometric assay with 4-Nitro-3 octanoyloxy-benzoic acid (4N3OBA). Cytotoxicity was done on C2C12 murine myoblast. Results: Fraction F5 and (+)-Catechin inhibited the PLA2 activity of B. asper venom, in a dosedependent way. In addition, (+) Catechin showed an inhibition level of 83.1 ± 3.1 % of the enzymati activity of one PLA2 purified from the venom of Crotalus durissus cumanensis using 4N3OBA as substrate. Also the ethanolic extract and fraction F5 showed inhibition of the cytotoxicity induced by the Bothrops atrox venom and their Lys 49 PLA2 (80 and 100% respectively). Molecular docking results suggested that OH from 4´ and 5' carbons of (+)-catechin could form hydrogen bonds with carboxylate moiety of residue Asp49, while OH from 5 could form a hydrogen bond with Asn 6. Additional Van der Waals interactions were also proposed. Conclusion: Swietenia macrophylla exhibited strong inhibitory activity against PLA2s enzymes. Catechin, one of the components in the active fraction F5, is proposed as being partially responsible for the bioactivity.

Antecedentes: Los efectos farmacológicos producidos en el accidente ofídico implican la acción de varias enzimas, como las fosfolipasas A2 (PLA2), que exhiben una amplia variedad de efectos como edema y miotoxicidad. Algunos extractos de plantas han demostrado ser antagonistas de los venenos crudos y sus toxinas. En base a una bioactividad promisoria previa, Swietenia macrophylla King fue seleccionada para estudios posteriores. Objetivo: El propósito de este estudio fue identificar metabolitos inhibidores de PLA2 presentes en el extracto crudo de S. macrophylla que podrían ser prometedores en la neutralización de los efectos locales del accidente ofídico. Métodos: Un fraccionamiento biodirigido del extracto etanólico de hojas de S. macrophylla llevó a la detección de la (+)-catequina mediante cromatografía de gases acoplada a espectrometría de masas (GC-MS), y se confirmó mediante HPLC. La actividad inhibidora de PLA2 se determinó por el método de Dole y un ensayo espectrofotométrico con Ácido 4-Nitro-3-octanoiloxibenzoico (4N3OBA). La citotoxicidad se determinó en mioblastos C2C12 murinos. Resultados: La fracción F5 de S. macrophylla, mostró la mayor inhibición del veneno de Bothrops asper y PLA2s aisladas de B. atrox y Crotalus durissus cumanensis e inhibición completa de la citotoxicidad. La (+)-catequina fue el metabolito más abundante en F5, mostró una inhibición de PLA2 de 89,8%, 81,1% y 74,3%, a diferentes relaciones de veneno: catequina. Mediante estudios de docking molecular se demostró la unión de la (+)-catequina al sitio activo de la PLA2. Conclusión: Swietenia macrophylla exhibió una fuerte actividad inhibitoria sobre las enzimas PLA2s. La (+)-catequina, uno de los metabolitos presentes en la fracción activa F5, se propone como uno de los compuestos responsables de la bioactividad.