Diameter distribution in a Brazilian tropical dry forest domain: predictions for the stand and species

ABSTRACT Currently, there is a lack of studies on the correct utilization of continuous distributions for dry tropical forests. Therefore, this work aims to investigate the diameter structure of a brazilian tropical dry forest and to select suitable continuous distributions by means of statistic tools for the stand and the main species. Two subsets were randomly selected from 40 plots. Diameter at base height was obtained. The following functions were tested: log-normal; gamma; Weibull 2P and Burr. The best fits were selected by Akaike's information validation criterion. Overall, the diameter distribution of the dry tropical forest was better described by negative exponential curves and positive skewness. The forest studied showed diameter distributions with decreasing probability for larger trees. This behavior was observed for both the main species and the stand. The generalization of the function fitted for the main species show that the development of individual models is needed. The Burr function showed good flexibility to describe the diameter structure of the stand and the behavior of Mimosa ophthalmocentra and Bauhinia cheilantha species. For Poincianella bracteosa, Aspidosperma pyrifolium and Myracrodum urundeuva better fitting was obtained with the log-normal function.

Bioatividade de três extratos de plantas no controle do Z abrotes subfasciatus (Boh) / Bioactividad de tres extractos de plantas en el control de Zabrotes subfasciatus (Boh) / Bioactivity three plant extracts in control of Zabrotes subfasciatus (Boh.)

Introdução: o conhecimento dos efeitos indesejáveis do uso de inseticidas químicos, associados à preocupação dos consumidores quanto à qualidade dos alimentos, têm exigido estudos sobre novas técnicas de controle das pragas de armazenamento, incluindo-se a utilização de produtos naturais que são menos agressivos ao ambiente, sendo exigido na produção orgânica e na agricultura familiar. Objetivo: avaliar a bioatividade inseticida de extratos vegetais em pó e hidroalcoólicos de Aspidosperma pyrifolium (Mart.), Anadenanthera colubrina (Vell.) e Licania rígida (Benth), a partir de folhas e casca do caule de cada espécie sobre a repelência/atratividade e mortalidade do Zabrotes subfasciatus (Boh.). Métodos: as plantas foram coletadas no sertão paraibano de Patos - PB e, os insetos de uma população pertencente ao Laboratório de Armazenamento e Processamento de Produtos Agrícolas / Universidade Federal de Campina Grande, mantidos em uma massa de feijão em estufa climática sob temperatura controlada. Resultados: constatou-se repelência do Z. subfasciatus a todos os extratos, com destaque para o extrato de L. rigida casca em que o Z. subfasciatus foi repelido em 82,49 por cento, seguidos do A. pyrifolium (78,88 por cento) e A. colubrina (77,49 por cento); o contrário deu-se com o extrato da L. rigida folhas que atraiu os insetos adultos em 40,29 por cento, constatando que os extratos cascas foram superiores aos extratos folhas. Em relação à mortalidade do inseto não se constatou diferença para os extratos das folhas e cascas, no tempo de 24 h, de A. pyrifolium e L. rigida, mas, para o A. colubrina folhas houve efeitos mais eficientes para mortalidade. Conclusão: os extratos foram eficientes no controle do Z. subfasciatus, em que o extrato A. pyrifolium casca se destaca na bioatividade matando em 100 por cento os insetos(AU)

Introducción: el conocimiento de los efectos adversos del uso de insecticidas químicos, asociado a las preocupaciones de los consumidores sobre la calidad de los alimentos, han requerido estudios sobre nuevas técnicas para el control de plagas de almacén, incluye, el uso de productos naturales que son menos dañinos, son exigido en la producción orgánica. Objetivo: evaluar la bioactividad de extractos de plantas con insecticidas hidroalcohólico y polvo de las hojas y la corteza del tallo de las especies Aspidosperma pyrifolium (Mart.), Anadenanthera colubrina (Vell.) y Licania rígido (Benth) en la repelencia/atractivo y mortalidad del Zabrotes subfasciatus (Boh.). Métodos: las plantas fueron recolectadas en tierras del interior de Paraíba (Patos ­ PB) y los insectos de una población pertenecientes al Laboratório de Armazenamento e Processamento de Produtos Agrícolas / Universidade Federal de Campina Grande, mantenidos en una masa de frijoles dentro de una cámara climática a temperatura controlada. Resultados: los adultos de Z. subfasciatus fueron repelidos por todos los extractos, empleados, a donde el extecto de la orteza de L. rígida repelio el Z. subfasciatus en 82,49 por ciento, seguido por A. pyrifolium (78,88 por ciento) y A. colubrina (77,49 por ciento); lo opuesto se dio con el extracto de las hojas de L. rígida que atrajeron a los insectos adultos en 40,29 por ciento, se examino, que los extractos de cáscara fueron superiores a los extractos de las hojas. En cuanto a la mortalidad del insecto no se encuentra diferencia para los extractos de las hojas y la corteza, en el tiempo de 24 h, de A. pyrifolium y L. rigida, pero para A. colubrina hojas, hubo efecto más significativo de mortalidad. Conclusión: los extractos fueron eficientes en el control del Z. subfasciatus, donde el extracto de la corteza de A. pyrifolium se destaca en la bioactividad, matando 100% los insectos(AU)

Introduction: the knowledge of the adverse effects of the use of chemical insecticides, associated to consumer concerns regarding to the quality of food, have required studies on new techniques for control of storage pests, including the use of natural products that are less aggressive to the environment, being required in organic production and family farming. Objective: evaluate the insecticidal bioactivity of powder plant extracts and hydroalcoholic of Aspidosperma pyrifolium (Mart.) , Anadenanthera colubrine (Vell.) and rigid Licania (Benth) from leaves and stem bark of each species on the repellency / attractiveness and mortality of the Zabrotes subfasciatus (Boh.). Methods: the plants were collected in backlands of Paraiba state, Patos - PB and the insects of a population belonging to Laboratório de Armazenamento e Processamento de Produtos Agrícolas / Universidade Federal de Campina Grande, kept in a mass of beans in a chamber under controlled temperature. Results: it was verified repellency of Z. subfasciatus to all extracts, highlighting the extract of rigid L. from bark in which the Z. subfasciatus was repulsed at 82.49 percent, followed by A. pyrifolium (78.88 percent) and A. colubrina (77.49 percent); the opposite happened with the extract of rigid L. from leaves which attracted the adult insects in 40.29 percent, noting that bark extracts were superior to the leaf extracts. In relation to mortality of the insect, is not observed difference for the extracts of the leaves and barks, in the time of 24h, of Apyrifolium and rigid L., but for A. colubrina from leaves there was more efficient effects for mortality. Conclusion: the extracts were efficient in the control of Z. subfasciatus in which the A. pyrifolium extract from bark stands out in the bioactivity killing 100 percent of the insects(AU)

Aspidosperma (Apocynaceae) plant cytotoxicity and activity towards malaria parasites. Part II: experimental studies withAspidosperma ramiflorum in vivo and in vitro

Several species of Aspidospermaplants are used to treat diseases in the tropics, including Aspidosperma ramiflorum, which acts against leishmaniasis, an activity that is experimentally confirmed. The species, known as guatambu-yellow, yellowperoba, coffee-peroba andmatiambu, grows in the Atlantic Forest of Brazil in the South to the Southeast regions. Through a guided biofractionation of A. ramiflorumextracts, the plant activity against Plasmodium falciparumwas evaluated in vitro for toxicity towards human hepatoma G2 cells, normal monkey kidney cells and nonimmortalised human monocytes isolated from peripheral blood. Six of the seven extracts tested were active at low doses (half-maximal drug inhibitory concentration < 3.8 µg/mL); the aqueous extract was inactive. Overall, the plant extracts and the purified compounds displayed low toxicity in vitro. A nonsoluble extract fraction and one purified alkaloid isositsirikine (compound 5) displayed high selectivity indexes (SI) (= 56 and 113, respectively), whereas compounds 2 and 3 were toxic (SI < 10). The structure, activity and low toxicity of isositsirikine in vitro are described here for the first time in A. ramiflorum, but only the neutral and precipitate plant fractions were tested for activity, which caused up to 53% parasitaemia inhibition of Plasmodium bergheiin mice with blood-induced malaria. This plant species is likely to be useful in the further development of an antimalarial drug, but its pharmacological evaluation is still required.

Climate change effects on the geographic distribution of specialist tree species of the Brazilian tropical dry forests / Efeitos das mudanças climáticas sobre a distribuição geográfica de espécies arbóreas especialistas de florestas secas tropicais brasileiras

AbstractThe aim of this study was to evaluate the ecological niche models (ENMs) for three specialist trees (Anadenantheracolubrina, Aspidosperma pyrifolium and Myracrodruon urundeuva) in seasonally dry tropical forests (SDTFs) in Brazil, considering present and future pessimist scenarios (2080) of climate change. These three species exhibit typical deciduousness and are widely distributed by SDTF in South America, being important in studies of the historical and evolutionary processes experienced by this ecosystem. The modeling of the potential geographic distribution of species was done by the method of maximum entropy (Maxent).We verified a general expansion of suitable areas for occurrence of the three species in future (c.a., 18%), although there was reduction of areas with high environmental suitability in Caatinga region. Precipitation of wettest quarter and temperature seasonality were the predictor variables that most contributed to our models. Climatic changes can provide more severe and longer dry season with increasing temperature and tree mortality in tropics. On this scenario, areas currently occupied by rainforest and savannas could become more suitable for occurrence of the SDTF specialist trees, whereas regions occupied by Caatinga could not support the future level of unsustainable (e.g., aridity). Long-term multidisciplinary studies are necessary to make reliable predictions of the plant’s adaptation strategies and responses to climate changes in dry forest at community level. Based on the high deforestation rate, endemism and threat, public policies to minimize the effects of climate change on the biodiversity found within SDTFs must be undertaken rapidly.

ResumoEste estudo tem como objetivo avaliar a modelagem de nicho ecológico (ENMs) para três espécies especialistas (Anadenantheracolubrina, Aspidosperma pyrifolium e Myracrodruon urundeuva) de florestas tropicais secas (FTSs) no Brasil, considerando o cenário de mudanças climáticas: presente e futuro pessimistas (2080). Estas três espécies são decíduas e amplamente distribuídas pelas FTSs na América do Sul, sendo importante em estudos sobre os processos históricos e evolutivos experimentados por este ecossistema. A modelagem da distribuição geográfica potencial das espécies foi construída através do método de máxima entropia (Maxent). Foi observada uma expansão geral de áreas adequadas para a ocorrência das três espécies no futuro (cerca de 18%), embora tenha existido uma redução das áreas com alta adequabilidade ambiental na região da Caatinga. A precipitação do trimestre mais úmido e a sazonalidade da temperatura foram os fatores que mais contribuíram para os nossos modelos. As mudanças climáticas podem gerar períodos secos mais severos e longos, com aumento da temperatura e mortalidade de árvores em regiões tropicais. Neste cenário, as áreas atualmente ocupadas por florestas úmidas e savanas poderiam tornar-se mais adequadas para a ocorrência das árvores especialistas em FTSs, enquanto que as regiões ocupadas por Caatinga não poderiam suportar o nível futuro da não adequabilidade (por exemplo, aridez). Estudos multidisciplinares de longa duração são necessários para fazer previsões confiáveis de estratégias adaptativas das plantas e respostas às variações climáticas em FTS em nível de comunidade. Com base na elevada taxa de desmatamento, endemismo e ameaça, políticas públicas para minimizar os efeitos das mudanças climáticas sobre a biodiversidade encontradas dentro FTSs devem ser realizadas rapidamente.

Germinação de sementes de Aspidosperma subincanumMart. ex A. DC em diferentes temperaturas / Germination of Aspidosperma subincanum Mart. ex A. DC seeds at different temperatures

RESUMO : Aspidosperma subincanum é uma espécie arbórea utilizada em projetos de recuperação de áreas degradadas e como planta medicinal. Levando-se em consideração a importância da espécie, o presente trabalho teve como objetivo definir a temperatura ideal para a germinação de suas sementes. O material vegetal foi coletado na região do Pantanal de Miranda, Mato Grosso do Sul. As sementes foram colocadas em caixas plásticas transparentes em câmara de germinação e submetidas às temperaturas constantes de 20, 25, 30 e 35°C e alternadas de 20-30 e 25-35°C. O delineamento experimental foi inteiramente casualizado, com quatro repetições por tratamento, sendo as médias comparadas pelo teste de Tukey a 5%. A temperatura ideal para a germinação de Aspidosperma subincanum foi a 25°C, com o maior índice de velocidade de germinação, 18,8. Temperaturas mais elevadas (30 e 35°C) causaram a morte dos embriões

ABSTRACT Germination of Aspidosperma subincanum Mart. ex A. DC seeds at different temperatures. The Aspidosperma subincanumem is a tree species used in the recovery of degraded areas projects and as a medicinal plant. Taking into account the importance of the species, the current study aimed to determine which would be the ideal temperature for the germination of their seeds. The plant material was collected in the Pantanal of Miranda, Mato Grosso do Sul. The seeds were placed in transparent boxes in germination chambers and submitted to constant temperatures of, 20, 25, 30 and 35°C and alternated at 20-30 and 25- 35°C, with four replicates per treatment. The statistical design was a completely randomized one. The averages were compared by Tukey test at 5%. The ideal temperature for germination of Aspidosperma subincanum was 25°C. The high temperatures (30 and 35°C) have caused the death of embryos

In vivo redox effects of Aspidosperma quebracho-blanco Schltdl., Lantana grisebachii Stuck and Ilex paraguariensis A. St.-Hil. on blood, thymus and spleen of mice.

Argentinian native plants Aspidosperma quebracho-blanco, Lantana grisebachii and Ilex paraguariensis are known to have antiinflammatory and antioxidant properties. We demonstrated it in vivo by the redox changes in murine hemolymphatic tissues after infusive extract intake of these plants as revealed in organic trophism, tissue phenolics, hydroperoxides, superoxide, nitrites and γ-glutamyltranspeptidase in thymus, blood and spleen. A. quebracho-blanco reduced hydroperoxidation in blood and spleen of both sexes, with γ-glutamyltranspeptidase negativization in lymphatic organs and thymic nitrosative up-regulation. Males have shown increased phenolic content in blood after treatment. L. grisebachii and I. paraguariensis treatment exhibited incomplete antioxidation and oxidative induction in the studied tissues. Different results according to sex were found in redox response to phenolics and their kinetics, with males showing antioxidant effects, whereas females showed oxidative susceptibility. A. quebracho-blanco exhibited protection of murine tissues against oxidation in both sexes and modulation of their trophism, supporting its therapeutic uses in inflammatory diseases. Also, gender had significant influence in phenolic biodistribution and redox response.

Aspidosperma (Apocynaceae) plant cytotoxicity and activity towards malaria parasites. Part I: Aspidosperma nitidum (Benth) used as a remedy to treat fever and malaria in the Amazon

Infusions of Aspidosperma nitidum (Apocynaceae) wood bark are used to treat fever and malaria in the Amazon Region. Several species of this family are known to possess indole alkaloids and other classes of secondary metabolites, whereas terpenoids, an inositol and the indole alkaloids harmane-3 acid and braznitidumine have been described in A. nitidum . In the present study, extracts from the wood bark, leaves and branches of this species were prepared for assays against malaria parasites and cytotoxicity testing using human hepatoma and normal monkey kidney cells. The wood bark extracts were active against Plasmodium falciparum and showed a low cytotoxicity in vitro, whereas the leaf and branch extracts and the pure alkaloid braznitidumine were inactive. A crude methanol extract was subjected to acid-base fractionation aimed at obtaining alkaloid-rich fractions, which were active at low concentrations against P. falciparum and in mice infected with and sensitive Plasmodium berghei parasites. Our data validate the antimalarial usefulness of A. nitidum wood bark, a remedy that can most likely help to control malaria. However, the molecules responsible for this antimalarial activity have not yet been identified. Considering their high selectivity index, the alkaloid-rich fractions from the plant bark might be useful in the development of new antimalarials.

Multiplicação in vitro de Aspidosperma ramiflorum Muell. Arg. (Apocynaceae) / In vitro multiplication of Aspidosperma ramiflorum Muell. Arg. (Apocynaceae)

O presente estudo relata um método simples e promissor para multiplicação in vitro de Aspidosperma ramiflorum, uma espécie encontrada no sudeste do Brasil e seriamente ameaçada de extinção, utilizada com propósitos medicinais e como fonte de compostos que podem ser usados para desenvolver novos fármacos sintéticos. O trabalho teve como objetivo o estabelecimento de um protocolo de multiplicação in vitro de Aspidosperma ramiflorum (guatambu), a partir de segmentos apicais de material juvenil originários de plântulas obtidos a partir de sementes. A avaliação da multiplicação in vitro foi realizada em meio de cultura Woody Plant Médium (WPM), suplementado com concentrações variadas de ácido naftalenoacético (ANA) e 6-Benzilaminopurina (6-BAP). A multiplicação de A. ramiflorum foi positivamente influenciada principalmente nas combinações aonde as concentrações de 6-BAP foram relativamente maiores do que as do ANA, nessas concentrações houve a indução de múltiplas brotações.

The present study described a simple and promissory method for in vitro multiplication of Aspidosperma ramiflorum, a species found in the South of Brazil and seriously extinction menaced. The method was used for medicinal proposes and as a source of compounds to develop new synthetic drugs. The objective of this work was to establish an in vitro multiplication protocol of Aspidosperma ramiflorum (guatambu), from apical segments of juvenile material of plantlets obtained from seeds. The in vitro multiplication evaluation was done in WPM medium, supplemented with variable concentrations of Naphthalene acetic acid (NAA) and 6- Benzyl aminopurine (6-BAP). The multiplication of A. ramiflorum was positively influenced mainly in the combinations when 6-BAP concentrations were relatively higher than NAA. In these concentrations multiple shoots were induced.

Plantas tóxicas para ruminantes e eqüídeos no Seridó Ocidental e Oriental do Rio Grande do Norte / Toxic plants for livestock in the western and eastern Seridó, state of Rio Grande do Norte, in the Brazilian semiarid

Para determinar a ocorrência de diferentes intoxicações por plantas na região do Seridó Ocidental e Oriental do Rio Grande do Norte foram entrevistadas 82 pessoas, entre produtores e técnicos em 17 municípios. De acordo com esse inquérito as duas intoxicações mais importantes são as por Ipomoea asarifolia, que causa sinais nervosos em ovinos, caprinos e bovinos, e por Aspidosperma pyrifolium que, segundo os entrevistados, causaria abortos em caprinos, ovinos e bovinos. O efeito abortivo desta última planta foi comprovado em caprinos, mas não em bovinos e ovinos. Alguns entrevistados mencionaram, também, a intoxicação por A. pyrifolium como causa de sinais nervosos em bovinos e eqüídeos, o que ainda não foi comprovado. Intoxicações por plantas cianogênicas, incluindo Manihot spp, Anadenanthera colubrina var. cebil (=Piptadenia macrocarpa), Sorghum bicolor e Sorghum halepense são importantes na região. São importantes, também, as intoxicações por Prosopis juliflora em bovinos e, com menor freqüência, em caprinos, por Crotalaria retusa em eqüinos, ovinos e bovinos e por Mascagnia rigida em bovinos. As intoxicações por Brachiaria decumbens e Enterolobium contortisiliquum ocorrem esporadicamente. Outras intoxicações menos importantes são as causadas por Indigofera suffruticosa, Ipomoea carnea e Ricinus communis. Diversos produtores descreveram a intoxicação por Marsdenia sp afetando ovinos e bovinos, além de um surto em suínos que foram alimentados com as raízes da planta. Foi demonstrado que tanto as raízes da planta quanto as folhas são tóxicas para ruminantes, causando sinais nervosos, mas sem lesões histológicas. Outra intoxicação relatada pelos produtores e comprovada experimentalmente foi a causada por Tephrosia cinerea em ovinos, que causa um quadro clínico de ascite, com lesões de fibrose hepática. Seis produtores descreveram a intoxicação por Nerium oleander, sempre em bovinos que tiveram acesso à planta após esta ter sido cortada e misturada ou não com...

To determine the occurrence of plant poisoning in the Western and Eastern Seridó regions of the state of Rio Grande do Norte, 82 persons including farmers, agronomists and veterinarians were interviewed. The two more important toxic plants are Ipomoea asarifolia, which causes nervous signs in sheep, goats and cattle, and Aspidosperma pyrifolium, leading to abortion in goats, sheep and cattle. The abortive properties of this plant had been demonstrated experimentally in goats, but not in sheep and cattle. Some farmers mentioned the poisoning by A. pyrifolium as a cause of nervous signs in equidae and cattle. Poisoning by cyanogenic plants including Manihot spp, Anadenanthera colubrina var. cebil (=Piptadenia macrocarpa), Sorghum bicolor and Sorghum halepense are important in the region. Important is also poisoning by Prosopis juliflora in cattle and with less frequency in goats, poisoning by Crotalaria retusa in horses, sheep and cattle, and by Mascagnia rigida in cattle. Poisoning by Brachiaria decumbens and Enterolobium contortisiliquum is sporadic. Other less important toxic plants in the region are Indigofera suffruticosa, Ipomoea carnea, and Ricinus communis. Some farmers reported poisoning by Marsdenia sp affecting sheep and cattle, and also a group of swine fed with the roots of the plant; the leaves and the roots are experimentally toxic to ruminants causing nervous signs, without histologic lesions. Another poisoning demonstrated experimentally is caused by Tephrosia cinerea and results in ascitis with hepatic fibrosis in sheep...

Antibacterial activity of indole alkaloids from Aspidosperma ramiflorum

We evaluated the antibacterial activities of the crude methanol extract, fractions (I-V) obtained after acid-base extraction and pure compounds from the stem bark of Aspidosperma ramiflorum. The minimum inhibitory concentration (MIC) was determined by the microdilution technique in Mueller-Hinton broth. Inoculates were prepared in this medium from 24-h broth cultures of bacteria (10(7) CFU/mL). Microtiter plates were incubated at 37°C and the MICs were recorded after 24 h of incubation. Two susceptibility endpoints were recorded for each isolate. The crude methanol extract presented moderate activity against the Gram-positive bacteria B. subtilis (MIC = 250 µg/mL) and S. aureus (MIC = 500 µg/mL), and was inactive against the Gram-negative bacteria E. coli and P. aeruginosa (MIC > 1000 µg/mL). Fractions I and II were inactive against standard strains at concentrations of <=1000 µg/mL and fraction III displayed moderate antibacterial activity against B. subtilis (MIC = 500 µg/mL) and S. aureus (MIC = 250 µg/mL). Fraction IV showed high activity against B. subtilis and S. aureus (MIC = 15.6 µg/mL) and moderate activity against E. coli and P. aeruginosa (MIC = 250 µg/mL). Fraction V presented high activity against B. subtilis (MIC = 15.6 µg/mL) and S. aureus (MIC = 31.3 µg/mL) and was inactive against Gram-negative bacteria (MIC > 1000 µg/mL). Fractions III, IV and V were then submitted to bioassay-guided fractionation by silica gel column chromatography, yielding individual purified ramiflorines A and B. Both ramiflorines showed significant activity against S. aureus (MIC = 25 µg/mL) and E. faecalis (MIC = 50 µg/mL), with EC50 of 8 and 2.5 µg/mL for ramiflorines A and B, respectively, against S. aureus. These results are promising, showing that these compounds are biologically active against Gram-positive bacteria.

Functional classification of esterases from leaves of Aspidosperma polyneuron M. Arg. (Apocynaceae)

Polyacrylamide gel electrophoresis system (PAGE) and inhibition tests for biochemical characterization of alpha- and beta-esterases were used to obtain a functional classification of esterases fromAspidosperma polyneuron. The characterization of alpha- and beta-esterases from young leaves of A. polyneuron by the PAGE system showed fourteen esterase isozymes. The differential staining pattern showed that Est-2 isozyme hydrolyzes beta-naphthyl acetate; Est-6, Est-7 and Est-8 isozymes hydrolyze alpha-naphthyl acetate, and Est-1, Est-3, Est-4, Est-5, Est-9, Est-10, Est-11, Est-12, Est-13, and Est-14 isozymes hydrolyze both alpha- and b-naphthyl acetate. Inhibition pattern of a- and beta-esterases showed that Folidol is a more potent inhibitor that Malathion, while Thiamethoxan (an insecticide with organophosphorus-like action) acts as an Est-4 and Est-6 inhibitor and induces the appearance of Est-5 and Est-7 isozymes as more intensely stained bands. Inhibition tests showed that OPC insecticides inhibit or activate plant esterases. Thus, plant esterases may be used as bioindicators to detect the presence and toxicity of residues of topically applied insecticides in agriculture and may be valuable for monitoring pollutants in the environment