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Resumen El presente trabajo muestra los resultados del estudio fitoquímico de las flores de Senna spectabilis y la evaluación de su capacidad antioxidante, para esto se recolectó el material vegetal en el municipio de Guaduas (Cundinamarca) y se identificó a través del Herbario Nacional Colombiano con el número de colección COL 600165; tras procesos de extracción por maceración en frío se obtuvieron 100 g de extracto etanólico, el cual fue fraccionado con solventes de polaridad creciente, obteniéndose fracciones de heptano, diclorometano y acetato de etilo, estas fueron sometidas a procesos de separación por cromatografía en capa fina (CCF) y cromatografía en columna (CC), la identificación tentativa de las mezclas obtenidas y los compuestos aislados se llevó a cabo mediante cromatografía de gases acoplada a espectrometría de masas (CG-EM), permitiendo identificar tres mezclas conformadas por compuestos tipo éster, cetona, antraquinona, monoterpenoide y un derivado del ácido cinámico, y los compuestos cinamato de metilo y cafeína. Se estudió la capacidad antioxidante de las fracciones obtenidas y el extracto etanólico por el método DPPH, además se realizó la medición de fenoles totales y la cuantificación de flavonoides. Los resultados indican que la fracción de diclorometano exhibió un porcentaje de inhibición superior a 30 % y que la mayor concentración de fenoles y flavonoides se encuentra en esta misma fracción. De esta manera, el trabajo dio un aporte químico (aislamiento de cinamato de metilo y cafeína, y tres mezclas) y un aporte biológico, tras identificar a la fracción de diclorometano obtenida de las flores de la especie como la que mayor cantidad de sustancias con capacidad antioxidante tiene respecto a otras fracciones y otros extractos. Abstract The present work shows the results of the phytochemical study of Senna spectabilis flowers and the evaluation of their antioxidant capacity, for this, the plant material was collected in the municipality of Guaduas (Cundinamarca) and identified through the Colombian National Herbarium with the number collection COL 600165, after extraction processes by cold maceration, 100 g of ethanolic extract were obtained, which was fractionated with solvents of increasing polarity, obtaining fractions of heptane, dichloromethane and ethyl acetate, then they were subjected to separation processes by Thin layer chromatography (TLC) and column chromatography (CC), the tentative identification of the obtained mixtures and isolated compounds was carried out by gas chromatography coupled to mass spectrometry (GC-MS), allowing the identification of three mixtures made up of ester, ketone, anthraquinone, monoterpenoid and a derivative of cinnamic acid compounds; and the compounds methyl cinnamate and caffeine. The antioxidant capacity of the obtained fractions and the ethanolic extract were studied by the DPPH method, in addition, the measurement of total phenols and the quantification of flavonoids were carried out. The results indicate that the dichloromethane fraction exhibited an inhibition percentage greater than 30 % and that the highest concentration of phenols and flavonoids is found in this same fraction. In this way, the work gave a chemical contribution (isolation of methyl cinnamate and caffeine, and three mixtures) and a biological contribution after identifying the fraction of dichloromethane obtained from the flowers of the species as the one with the greatest amount of substances with antioxidant capacity. has respect to the other fractions and extracts. Resumo O presente trabalho apresenta os resultados do estudo fitoquímico de flores de Senna spectabilis e a avaliação de sua capacidade antioxidante, para isso, o material vegetal foi coletado no município de Guaduas (Cundinamarca) e identificado através do Herbário Nacional da Colômbia com a coleção numérica COL 600165, após processos de extração por maceração a frio, foram obtidos 100 g de extrato etanólico, o qual foi fracionado com solventes de polaridade crescente, obtendo-se as frações de heptano, diclorometano e acetato de etila, a seguir foram submetidos a processos de separação por cromatografia em camada delgada (CCD) e cromatografia em coluna (CC), a identificação tentativa das misturas obtidas e dos compostos isolados foi realizada por cromatografia gasosa acoplada a espectrometria de massa (GC-MS), permitindo a identificação de três misturas constituídas de éster, cetona, antraquinona, monoterpenóide e um derivado de compostos de ácido cinâmico; e os compostos cinamato de metilo e cafeína. A capacidade antioxidante das frações obtidas e do extrato etanólico foram estudadas pelo método DPPH, além disso, foi realizada a dosagem de fenóis totais e a quantificação de flavonóides. Os resultados indicam que a fração diclorometano exibiu um percentual de inibição superior a 30 % e que a maior concentração de fenóis e flavonóides é encontrada nesta mesma fração. Desta forma, o trabalho deu uma contribuição química (isolamento de cinamato de metila e cafeína, e três misturas) e biológica após identificar a fração de diclorometano obtida das flores da espécie como aquela com maior quantidade de substâncias com antioxidante. capacidade. tem relação com as outras frações e extratos.

In tropical dry forest conditions, small ruminant production is an alternative for small farmers. Even so, the quality of the forages does not meet the nutritional requirements of the animals. However, the high biodiversity of trees that exist in the region offers a supplementation alternative especially during the dry season. The objective of this research work was to evaluate the quality and the profile effect of fatty acids in Colombian creole lamb meat supplemented with tree species from the tropical dry forest. A total of 35 lambs were used which were randomly distributed in 5 treatments as follows: T1: Botriochloa pertusa; T2: Botriochloa pertusa + 300 g/day of Leucaena leucocephala; T3: Botriochloa pertusa + 300 g/day of Gliricidia sepium; T4: Botriochloa pertusa + 300 g/day of Guazuma ulmifolia and T5 (BpSs): Botriochloa pertusa + 300 g/day of Senna spectabilis. The experimental units were brought to a final slaughter weight of ±32 kg and the pH, color, and fatty acid composition of the carcasses were evaluated at 24 hours. The meat quality parameters did not present significant differences (P>0.05) in the different supplements and obtained acceptable parameters for their consumption. It was evidenced that the proportions of saturated fatty acids (C 16: 0, C 18: 0, total SFA) in lambs supplemented with Senna spectabilis and Gliricidia sepium were lower (P< 0.05). It is concluded that under the conditions of the study the supplementations with Senna spectabilis and Gliricidia sepium can induce a favorable change in the fatty acid content of lamb meat. Resumen En condiciones de bosque seco tropical, la producción de pequeños rumiantes es una alternativa para los pequeños agricultores. No obstante, la calidad de los forrajes no atiende a los requerimientos nutricionales de los animales. Sin embargo, la alta biodiversidad de árboles que existe en la región ofrece una alternativa de suplementación especialmente en la época seca. El objetivo de este trabajo de investigación fue evaluar la calidad y el perfil de ácidos grasos en carnes de corderos criollos colombianos suplementados con especies arbóreas del bosque seco tropical. Se utilizaron 35 corderos los cuales fueron distribuidos aleatoriamente en 5 tratamientos: T1 (control) = pastoreo en Botriochloa pertusa; T2= pastoreo en Botriochloa pertusa + 300 gr/día de suplemento a base de Leucaena leucocephala; T3= pastoreo en Botriochloa pertusa + 300 gr/día de Gliricidia sepium; T4= pastoreo en Botriochloa pertusa + 300 gr/día de Guazuma ulmifolia y T5= pastoreo en Botriochloa pertusa + 300 gr/día de Senna spectabilis. Las unidades experimentales fueron llevadas a un peso final de sacrificio de ± 32 kg y se evaluó el pH a las 24 horas, el color y el perfil lipídico de las canales. Los parámetros de calidad de la carne no presentaron diferencias estadísticas significativas (P>0.05) en las diferentes suplementaciones y obtuvieron parámetros aceptables para su consumo. Se evidencio que las proporciones de ácidos grasos saturados (C 16:0, C 18:0, total de SFA) en los corderos suplementados con Senna spectabilis y Gliricidia sepium fueron menores (P< 0.05). Se concluye que bajo las condiciones del estudio las suplementaciones con Senna spectabilis y Gliricidia sepium pueden inducir un cambio favorable en el contenido de ácidos grasos de la carne de corderos.

A review of the Leguminosae Cesalpinioideae growing naturally in the territory of Santa Fe province, Argentina, is presented as a contribution to the study of the flora of this province. A total of 19 species belonging to 9 genera are included. The following taxa are excluded from the flora of Santa Fe: Senna aphylla (Cav.) H.S. Irwin & Barneby y Senna spectabilis (DC.) H. S. Irwin & Barneby. For each genus, keys for the recognition of its species are provided. For each taxon, the following items are included: the correct name acceted by the botanical community and, when applicable, its basionym; vernacular names, a reference specimen, habitat, iconography, geographical distribution and ecological and phenological observations. Como contribución al estudio de la fl ora de Santa Fe, se presenta la revisión sinóptica de las Leguminosas Cesalpinioideas que crecen espontáneamente en el territorio de esta provincia. En total se incluyen 19 especies distribuidas en 9 géneros. Los siguientes taxones: Senna aphylla (Cav.) H.S. Irwin & Barneby y Senna spectabilis (DC.) H. S. Irwin & Barneby, son excluidos de esta fl ora. Para cada género se proporcionan claves que permiten el reconocimiento de sus especies. Para cada taxón se incluye su nombre correcto aceptado por la comunidad botánica y, cuando corresponde, su basónimo; nombres vernáculos, ejemplares de referencia, hábito, iconografía, distribución geográfi ca y observaciones fenológicas y ecológicas.

Senna spectabilis (DC.) H.S. Irwin & Barneby is a popular ornamental tree as well as a traditional medical plant in Cameroon. In this study, we sequenced and annotated the complete chloroplast genome of S. spectabilis and reconstructed the phylogenetic relationship of the tribe Cassieae. The length of the chloroplast genome was determined to be 162,754 bp, containing a pair of inverted repeats of 25,413 bp which separated by a small single-copy (SSC) region of 20,161 bp and a large single-copy (LSC) region of 91,767 bp. The cp genome encodes 128 genes, including 83 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The percentage of total GC content of this genome was 35.7%. The phylogenetic analysis indicates that S. spectabilis with the sampled Senna species formed a well-supported monophyletic clade.

Made available in DSpace on 2022-05-01T10:51:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 In this study, we investigated the phenolic and antioxidant content, cytotoxic, and anticholinesterase activities of flower extracts of Senna spectabilis var. excelsa and Senna macranthera. The antioxidant activities performed by the DPPH and ABTS methods showed that the extracts possess good antioxidant activity, with emphasis on the S. macranthera extract, which obtained results very similar to the rutin pattern. In the evaluation of the cytotoxic activity, the species S. spectabilis var. excelsa presented expressive cytotoxicity against the cellular lines PC3 and HL60 with IC50 values 21.08 and 31.37 μg mL−1, respectively. The results of anticholinesterase activity showed that both the plants induced enzyme inhibition, reaching 14 mm of inhibition in the case of S. spectabilis var. excelsa. The good results obtained in this work may be related to the presence of compounds such as apigenin-7-apioglucoside, quercetin 3,4'-diglucoside, cassine and spectaline identified in the extracts in our previous work. Department of Organic and Inorganic Chemistry/Department of Analytical Chemistry and Physical-Chemistry Federal University of Ceará Department of Physiology and Pharmacology Federal University of Ceará Chemistry Institute São Paulo State University - UNESP Chemistry Institute São Paulo State University - UNESP

The Bakonjo have long practiced an agroforestry system of cultivation on the Ugandan slopes of the Rwenzori Mountain range. All terrain above 1600–2200 m has been strictly protected for many years because it is part of a national park. As a trade-off, the landscapes outside the park have been largely deforested. In the meantime, tourist numbers have increased. In Ruboni, a village of 1200 people, the closest to the eastern gate of the park, we interviewed a random sample of 51 residents aged >14 to understand how they perceived the landscape, park and tourism. Cultivated features were not essential to describe the place of residence, in contrast to natural features and human engineered devices. Cultivated and natural elements were judged as beautiful. Even if the inhabitants did not like human engineered facilities, they welcomed their improvement. The origin of native and non-native plants was not consistently recognized. These results show that the inhabitants feel affection for the agroforestry pattern of the Rwenzori landscape. However, ecological, social and economic pressures are challenging land use sustainability. This would be better addressed by an integrated pattern of land governance than the current two models: strict protection inside the park and relaxed land use outside.

SUMMARYA large body of evidence demonstrates the agronomic superiority of maize hybrids over open-pollinated varieties (OPVs) in intensive monoculture. However, comparisons of the performance of hybrids and OPVs in agroforestry systems are scarce. In this study, the performance of four maize hybrids and four OPVs is compared in sole crop and under mature trees. Experiments were conducted on-farm during four seasons in Bugesera, Rwanda and two seasons in Meki, Ethiopia. Two tree species were selected in Bugesera (Grevillea robusta and Senna spectabilis) and one in Meki (Acacia tortilis), and three farms were selected for each tree species, each including two plots with almost identical trees in their centre and two plots without tree. In Bugusera, grain yield was higher for hybrids (2 Mg ha−1) than for OPVs (1.5 Mg ha−1), and the presence of trees reduced the harvest index more in OPVs than in hybrids. In this region, the estimated reduction in grain yield due to the presence of trees was 0.9 and 1.1 Mg ha−1 in hybrids and OPVs, respectively, while estimated reduction in biomass was 1.5 and 1.7 Mg ha−1, respectively. In Meki, the grain yield of OPVs (2.08 Mg ha−1) and hybrids (2.04 Mg ha−1) did not differ and the presence of trees reduced their grain yields in the same manner. Our results showed that hybrids yielded more than OPVs under G. robusta and S. spectabilis in Bugesera but performed equally well under A. tortilis in Meki. We conclude that agroforestry farmers could benefit from growing hybrids in the equatorial savannahs of Rwanda, but that the choice between hybrid and OPV in equatorial savannahs of Ethiopia can simply be based on other factors such as seed costs and availability.

This study aimed at identifying the tree species commonly used in brick making in Morogoro Municipality, Tanzania and proposing means for generation of modified energy sources that would cover the full value of forest resource production and consumption. The research approach was two-folds using; Participatory Rural Appraisal (PRA) and quantitative measurements. Results revealed that almost all brick makers in the area used fuelwood as the major energy sources. Nine (9) tree species were used in brick making, namely; Mkarati (Burkea africana), Mlama (Combretum molle), Mbiriti (Senna siamea), Muarobaini (Azadirachta indica) and Mwembe (Mangifera indica). Others were Mkaratusi (Eucalyptus spp), Mchongoma (Pithecellobium dulce) Mjohoro (Senna spectabilis) and Mkrisimasi (Delonix regia). Of these, Mkarati, Mwembe, Mlama and Mbiriti were mostly preferred, though other species were also used insignificantly. Increasing scarcity of some of other tree species meant that deforestation from the nearby forests was a common problem. To reduce deforestation in the area, use of alternative energy sources in brick making such as rice husks and bagasse are recommended. Other recommendations are the establishment of woodlots, practicing agro-forestry systems and intensive afforestation and reforestation programmes for more sustainable fuelwood use.

Three new isoaigialones, A, B, and C (1–3), along with aigialone (4), were isolated from the crude EtOAc extract of a Phaeoacremonium sp., an endophytic fungus obtained from the leaves of Senna spectabilis. The structures of these compounds were elucidated based on the analysis of spectroscopic data. Compounds 2 and 4 were active against the phytopathogenic fungi Cladosporium cladosporioides and C. sphaerospermum. This is the first report of metabolites produced by an Phaeoacremonium sp., associated with S. spectabilis.

Senna spectabilis (DC.) H.S. Irwin & Barneby is a popular ornamental tree as well as a traditional medical plant in Cameroon. In this study, we sequenced and annotated the complete chloroplast geno...

O objetivo desta pesquisa foi testar o efeito do Hydropriming para a promoção da emergência e do vigor em sementes provenientes de populações do bioma Caatinga. Assim sendo, foram testadas as espécies: Sesbania virgata, Anadenanthera colubrina, Luetzelburgia auriculata, Cenostigma pyramidale, Vachelia farnesiana, Piptadenia retusa, Senna spectabilis, Mimosa tenuiflora, Sarcomphalus joazeiro e Enterolobium contortisiliquum. Houveram dois tratamentos: 1) imersão em água (Hydropriming) por 24h a 25°C e 2) incubação por 24h a 25°C sem imersão. Foram avaliadas variáveis de emergência e vigor. Os resultados obtidos foram testados por Qui-quadrado e testes Não-paramétricos. A tecnologia de Hydropiming não foi vantajosa para espécies estudadas nesta pesquisa, exceto para Anadenanthera colubrina e Luetzelburgia auriculata. Sendo, portanto, a imersão por 24h a 25°C potencial para promoção da emergência e vigor de A. colubrina e L. auriculata, outras pesquisas podem ser realizadas para melhorar a utilização desta metodologia em virtude de um melhor manejo destas espécies.

Senna spectabilisis known to have antimicrobial, laxative, antiulcerogenic, analgesic, and anti-inflammatory properties in folk medicine. Piperidine alkaloids extracted from various parts of this plant have been shown to have anticonvulsant (iso-6-spectaline), antinociceptive [(-)-spectaline] and lipid peroxidation [(+)-3-O-feruloylcassine, (-)-spectaline and (-)-3-O-acetylspectaline] activities. In our study, the ethyl acetate extract fromS. spectabilisexhibited antileishmanial activity via intracellular promastigote assay or leishmanicidal assay and was further fractionated by using bioassay-guided isolation approach. The antiprotozoal principle was isolated from the ethyl acetate portion through solvent fractionation and a few series of chromatographic processes. The isolated active compound 1 was identified as (+)-spectaline on the basis of its spectral analysis (MS, 1D & 2D NMR) with EC50value of 0.063 ± 0.005 µM for antileishmanial activity and selectivity index of 3.76.

O objetivo do presente estudo foi identificar a composição química da Senna spectabilis, averiguar o potencial antimicrobiano in vitro e analisar seu efeito modulador da atividade antibiótica. Os ensaios fitoquímicos foram realizados seguindo o método proposto por Matos (1997), baseando-se na observação visual de alteração de cor ou formação de precipitado após a adição dos reagentes específicos. Os testes de Concentração Inibitória Mínima (CIM) e modulação foram determinados pelo ensaio de microdiluição em caldo, seguindo as recomendações do Clinical and Laboratory Standards Institute (CLSI). As cepas utilizadas foram Saphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa e Salmonella entérica. Após essas análises se verificou a presença significativa dos metabólitos secundários taninos condensados, alcaloides, esteroides e saponinas. Nos resultados referentes à avaliação da ação antimicrobiana do extrato de S. spectabilis contra as cepas testadas se observou que houve crescimento bacteriano em todas as concentrações aplicadas, não apresentando assim nenhuma CIM clinicamente relevante. Na modulação, o extrato em combinação com os antibióticos testados mostrou efeito sinérgico contra a maioria das bactérias testadas, potencializando o efeito dos antibióticos utilizados. Portanto, este estudo abre caminho para futuras pesquisas que auxiliem a identificar na S. spectabilis, moléculas que atuem sinergicamente a antibióticos, tornando-se uma alternativa como adjuvante de antimicrobianos e no combate a infecções bacterianas resistentes às diversas drogas. Palavras-chave: Atividade Antibacteriana. Senna spectabilis. Fitoquímica. Sinergismo. AbstractThe objective of the present study was to identify the chemical composition of Senna spectabilis, to investigate the in vitro antimicrobial potential and to analyze its modulating effect of antibiotic activity. Phytochemical assays were performed following the method proposed by Matos (1997), based on visual observation of color change or precipitate formation after the addition of specific reagents. The Minimum Inhibitory Concentration (MIC) and modulation tests were determined by the broth microdilution assay, following the recommendations of the Clinical and Laboratory Standards Institute (CLSI). The strains used were Saphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella enterica. After these analyzes, it was verified the significant presence of the secondary condensed tannin metabolites, alkaloids, steroids and saponins. In the results regarding the evaluation of the antimicrobial action of S. spectabilis extract against the tested strains it was observed that there was bacterial growth in all the applied concentrations, thus presenting no clinically relevant MIC. In modulation, the extract in combination with the tested antibiotics showed synergistic effect against most of the tested bacteria, enhancing the effect of the antibiotics used. Therefore, this study paves the way for future research to help identify S. spectabilis molecules that act synergistically to antibiotics, becoming an alternative as an adjunct to antimicrobials and in the fight against bacterial infections resistant to various drugs. Keywords: Antibacterial Activity. Senna spectabilis. Phytochemistry. Synergism.

Arbuscular mycorrhizal fungi (AMF) help to facilitate mobilization of nutrients from soil to plant. The study was carried out in humid Rubavu and semi-arid Bugesera districts in Rwanda. We hypothesized that the presence of tree species in farming systems enhances mycorrhizal fungal density. The occurrence and abundance of AMF in the soil around main agroforestry tree species in these regions was studied. Tree species in Rubavu included Alnus acuminata, Markhamia lutea, Grevillea robusta and Eucalyptus sp. and in Bugesera Acacia polyacantha, Senna spectabilis, Grevillea robusta and Eucalyptus sp. AMF spores were isolated from soil samples collected under and outside the trees canopies. Results show significant differences in spore density between species. The density of AMF spores was highest under A. acuminata and A. polyacantha and lowest in Eucalyptus sp. and G. robusta in Rubavu and Bugesera, respectively. Generally, the mean spore abundance (spores/g of soil) was significantly higher in Bugesera (3.1-6.6) than Rubavu (1.6-4.4). Spores abundance was also affected by distance from the tree trunk and tree size. The present work is the first attempt to study the AMF communities associated with tree species in agroforestry systems in Rwanda. We propose further studies relating mycorrhizal diversity in the agroforestry systems to performance and yields of crops. Key words: Arbuscular mycorrhizal fungi, spore abundance, agroforestry system.

Senna spectabilis (Fabaceae) is one of the medicinal plants used in Cameroon by traditional healers to treat epilepsy, constipation, insomnia, anxiety. The present study aimed to investigate the anticonvulsant effects of Senna spectabilis decoction on seizures induced by maximal electroshock (MES), pentylenetetrazole (PTZ), pilocarpine (PC) and its possible action mechanisms in animal models using flumazenil (FLU), methyl-s-carboline-3-carboxylate (BC) and bicuculline (BIC). Senna spectabilis decoction (106.5 and 213.0mg/kg) antagonized completely tonic-clonic hind limbs of mice induced by MES. The lowest plant dose (42.6mg/kg) provided 100% of protection against seizures induced by PTZ (70mg/kg). Administration of different doses of the plant decoction antagonized seizures induced by PC up to 75%, causing a dose dependent protection and reduced significantly the mortality rate induced by this convulsant. Both FLU and BC antagonize strongly the anticonvulsant effects of this plant and are unable to reverse totally diazepam or the plant decoction effects on inhibiting seizures. The animals did not present any sign of acute toxicity even at higher doses of the plant decoction. In conclusion, Senna spectabilis possesses an anticonvulsant activity. We showed that its decoction protects significantly mice against seizures induced by chemicals and MES, delays the onset time and reduces mortality rate in seizures-induced. It also appears that the oral administration of the decoction of S. spectabilis is more active than the intraperitoneal administration of the ethanolic extract on inhibiting seizures induced by MES and PTZ. Moreover, the plant decoction could interact with GABAA complex receptor probably on the GABA and benzodiazepines sites.

In our ongoing work searching for new trypanocidal lead compounds from Malaysian plants, two known piperidine alkaloids (+)-spectaline (1) and iso-6-spectaline (2) were isolated from the leaves of Senna spectabilis (sin. Cassia spectabilis). Analysis of the 1H and 13C NMR spectra showed that 1 and 2 presented analytical and spectroscopic data in full agreement with those published in the literature. All compounds were screened in vitro against Trypanosoma brucei rhodesiense in comparison to the standard drug pentamidine. Compound 1 and 2 inhibited growth of T. b. rhodesiense with an IC50 value of 0.41 ± 0.01 μM and 0.71 ± 0.01 μM, without toxic effect on L6 cells with associated a selectivity index of 134.92 and 123.74, respectively. These data show that piperidine alkaloids constitute a class of natural products that feature a broad spectrum of biological activities, and are potential templates for the development of new trypanocidal drugs. To our knowledge, the compounds are being reported for the first time to have inhibitory effects on T. b. rhodesiense. The ultrastructural alterations in the trypanosome induced by 1 and 2, leading to programmed cell death were characterized using electron microscopy. These alterations include wrinkling of the trypanosome surface, formation of autophagic vacuoles, disorganization of kinetoplast, and swelling of the mitochondria. These findings evidence a possible autophagic cell death.

Senna spectabilis (sin. Cassia excelsa, C. spectabilis) is an endemic tree of South America and Africa, very common in Brazil, where it is known as "canafistula-de-besouro" and "cassia-do-nordeste". In folk medicine, this plant is indicated for the treatment of constipation, insomnia, anxiety, epilepsy, malaria, dysentery and headache. Phytopharmacological studies have also confirmed anticonvulsive, sedative, anti-malarial, antimicrobial and cytotoxic properties of many parts of S. spectabilis. In this communication, we present a comparative study of the leishmanicidal activity of the crude ethanolic extract, its fractions and also the two major alkaloidal metabolites (-)-cassine/(-)-spectaline, trying to establish a relationship between the presence of piperidine alkaloidal constituents and leishmanicidal activity. The growth inhibitory effect of promastigote forms of Leishmania major was determined for the crude extract, fractions of the flowers of S. spectabilis and a mixture of (-)-cassine/(-)-spectaline in comparison to pentamidine used as standard drug. The cytotoxic effects were assessed on macrophage strain J774 by lactate dehydrogenase assay. Fractions dichloromethane (FL-DCM) and n-butanol (FL-Bu) and a mixture of (-)-cassine/(-)-spectaline (∼7:3) exhibited significant activity against the parasite Leishmania major (IC50 values of 0.6±0.1 μg/ml, 1.6±0.9 μg/ml and 24.9±1.4 μg/ml, respectively), without toxic effects on murine macrophages. Due to the promising results elicited, further studies in vivo need to be performed to confirm the therapeutic potential of Senna spectabilis.

Despite significant evidence that green manures from agroforestry species can improve soil fertility, green biomasses from many agroforestry species have not been sufficiently explored. In this study, we determined the suitability of green manures of Tithonia diversifolia, Gliricidia sepium, and Senna spectabilis for smallholder agriculture in Africa. Field trials were established to compare them with mineral fertilizer. The results showed that green manures of the three species were of high quality based on their macronutrient compositions. The effect of the green manures (particularly Tithonia) on both the biomass and fruit yield of okro were comparable and in some cases greater than fertilizer treatments. Total yield response in Tithonia treatment was 61% and 20% greater than the control and fertilizer treatments, respectively. In addition, the okro plants recovered a greater percentage of the nitrogen (N), phosphorus (P), and potassium (K) added as green manure compared to fertilizer-treated plots, wh...

Twenty weeks forage re-growth from 20 multipurpose trees and shrubs (MPTS) species (Albizia ferruginea, Albizia gummifera, Albizia niopoides, Berlinia grandiflora, Bauhimia monandra, Dialium guineense, Dalbergia sissoo, Enterolobium cyclocarpum, Leucaena leucocephala, Lonchocarpus sericeus, Milletia griffoneanus, Milletia thoningii, Napoliana imperialis, Parkia bicolor, Pterocarpus santalinoides, Senna spectabilis, Treculia africana, Terminalia superba, Tetrapluera tetraptera and Xylia xylocarpa) were investigated for their feed value. The MPTS were grown on an ultisol in southeastern Nigeria and were subjected to proximate analyses, nylon bag degradability studies and cluster analysis. Among species, crude protein (CP) ranged from 104 g kg−1 DM in P. bicolor to 205 g kg−1 DM in A. gummifera, neutral detergent fibre (NDF) ranged from 498 g kg−1 DM in L. leucocephala to 771 g kg−1 DM in L. sericeus, acid detergent fibre (ADF) ranged from 303 g kg−1 DM in T. superba to 661 g kg−1 DM in L. sericeus, acid detergent lignin (ADL) ranged from 75 g kg−1 DM in T. superba to 305 g kg−1 DM in L. sericeus. Also, ADF-ash ranged from 0.78 g kg−1 DM in E. cyclocarpum to 15.58 g kg−1 DM in D. guineense. Except E. cyclocarpum and S. spectabilis, the remaining 18 MPTS studied had effective degradabilities (ED) less than 500 g kg−1 DM effective degradability. Eight MPTS (A. ferruginea, A. niopoides, B. monandra, D. sissoo, E. cyclocarpum, L. leucocephala, S. spectabilis, T. superba) were classified as high quality, another eight (A. gummifera, B. grandiflora, L. sericeus, N. imperialis, P. bicolor, P. santalinoides, T. tetraptera and X. xylocarpa) as medium quality while, the remaining four (D. guineensis, M. griffoneanus, M. thoningii, T. africana) fell into the low quality class based on their nutrient composition and ruminal DM degradability. The results indicate that most of the MPTS could be used as good quality feed for small ruminants in Nigeria.

Made available in DSpace on 2018-11-27T19:49:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-09-01 Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) In this work, we present the in vitro schistosomicidal activity evaluation of the most active dichloromethane fraction (FDm) (ED50 = 83.5 mu g/mL) and of a mixture of the major alkaloids ((-)-cassine/(-)-spectaline, C/E) (ED50 = 37.4 mu g/mL) from the flowers of Senna spectabilis against adult worms and cercariae. We also demonstrate other toxic effects including paralysis of the adult worms, inhibition of the secretory activity, tegument lesions and cercaricidal activity. In the association test of Praziquantel (PZQ)-C/E, we observed up to 80% mortality of Schistosoma mansoni in comparison to PZQ monotherapy. Due to the diversity of the toxic effects, the schistosomicidal activity of C/E is likely a result of a multitarget mechanism involving the tegument, secretory system and neuromotor action. (C) 2016 Elsevier Ltd. All rights reserved. Univ Fed Alfenas Minas Gerais, BR-37130000 Alfenas, Brazil Univ Estadual Paulista Sao Paulo, BR-14800060 Araraquara, Brazil Univ Fed Uberlandia Minas Gerais, BR-38408100 Uberlandia, MG, Brazil Univ Estadual Paulista Sao Paulo, BR-14800060 Araraquara, Brazil

Plant products are used as the primary health care in developing countries due to their availability and affordability compared to conventional methods. It is estimated that more than 80% of the world’s population use herbal preparations in the management and treatment of diseases. Herbal products are now readily available in supermarkets and drug stores. The therapeutic value of these herbal products is believed to be due to the presence of bioactive elements present in the plant parts. Toxicity studies should, however be carried to ascertain the safety of the herbal preparation. In this study, safety studies were carried out through biochemical assays, histopathology and hematological tests. The plant extracts led to changes in body weight, hematological and histopathological changes like increase in lymphocyte number. High dose of orally administered Olinia usambarensis also caused microcytic hypochromic anemia. Senna spectabilis and Olinia usambarensis revealed intense infiltration of inflammatory cells causing necrosis and loss of cellular details of the kidney. This study will enhance understanding of the safety of ethno-medical materials in the management of diarrhea caused by bacterial pathogens.

This paper presents the results of a household survey designed to qualitatively evaluate the impacts of the invasive alien species Senna spectabilis on the distribution of welfare across dependent communities in the Budongo Forest Reserve (BFR) in Uganda. The BFR is the largest forest reserve in Uganda, with globally significant conservation values. The study establishes that households in the BFR have high levels of knowledge as to its conservation values; they are aware of the invasiveness of S. spectabilis and its potential to compromise the conservation values of the BFR, and that S. spectabilis confers tangible benefits to dependent households, whose levels significantly vary with proximity to the reserve. The study concludes by evaluating strategies that are designed to manage the spread of S. spectabilis in the BFR and which consider its demonstrated socio-economic impacts.

The effect of shoot pruning on leaf phenology, stem wood anatomy and sap flow was investigated on Senna spectabilis (DC.) Irwin and Barneby in Machakos, Kenya. Unpruned trees (single stem) were compared to hedges (two to four stems), pruned 4 times a year during two rainy seasons (April–June, 1997 and November, 1997–January, 1998) separated by a dry season (July–October 1997). Trees attained peak leaf area of 55 m2 plant−1 during the rainy seasons, and shed all their leaves naturally during the dry season. Maximum hedge leaf area was 4 m2 plant−1 between pruning events and 5.2 m2 plant−1 during the dry season. Pruning induced multiple stems and narrow xylem vessels with low hydraulic conductivity. Average cross sectional area of conducting wood per plant was at least 1.8 times greater in trees than in hedges. Xylem lumen diameter at 5 mm depth below the cambium was significantly (P

Biomass production and nutrient uptake of all components in planted Senna spectabilis, Dactyladenia barteri and Flemingia macrophylla hedgerow fallow were determined after three two‐year fallow phases and compared to natural fallow. Total above-ground biomass production after each of three fallow phases was significantly higher in the Senna system than any other system. Total above ground biomass production in the Flemingia and the Dactyladeniai system was not different from that in natural fallow. The volunteer biomass between hedgerows was only once significantly reduced by S. spectabilis during the first fallow phase. The amount of litter did not differ between fallow systems. The biomass of S. spectabilis, F. macrophylla and D. barteri comprised 96%, 95% and 65% wood, respectively. Relative to the total system biomass, wood constituted 67% in S. spectabilis and about 20% in F. macrophylla and D. barteri systems. Except for Mg, the S. spectabilis system accumulated more nutrients in above ground biomas...

Lack of crop yield response to planted tree fallow led to introducing a two-year fallow phase to determine if planted tree fallow can improve soil fertility and yields over a no-tree control. Three cycles of two years fallow followed by slash-and-burn land preparation and one year of groundnut/cassava/maize intercropping were conducted with Senna spectabilis, Flemingia macrophylla and Dactyladenia barteri as planted hedgerow fallows and a no-tree control on an Ultisol in southern Cameroon. The land had been continuously cropped to maize/cassava intercrop for 5 years previous to the first two-year fallow phase. Groundnut grain yields were unaffected by fallow system in 1998 and 2001 and the sum of the three cropping years. Maize grain yield was unaffected by fallow system in 1998. In 2001 and 2004 maize grain yield was highest in the S. spectabilis system. Total maize grain yield across the three cropping years was higher in the F. macrophylla and S. spectabilis systems than in the D. barteri syst...

Made available in DSpace on 2018-11-27T08:57:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-03-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Brazilian Agency FINEP Cancer is one of the most critical problems of public health in the world and one of the main challenges for medicine in this century. Unfortunately, most patients are diagnosed at advanced stage, when the treatment options are palliative. Consequently, the search for novel therapeutic options is imperative. In the context, the plants represent an important source for discovering of novel compounds with pharmacological potential including antineoplastic agents. Herein, we aimed to investigate in vitro antiproliferative and cytotoxic potentials of an alkaloid mixture derived from Senna spectabilis, (-)-cassine (1) and (-)-spectaline (2). These alkaloids reduced cell viability in a concentration-dependent manner of six tumor cell lines. From initial screening, HepG2 cells were selected for further investigations. We show that alkaloids 1/2 have an important antiproliferative activity on HepG2 cells due to their ability in inducing cell cycle arrest in G1/S transition. This effect was associated to ERIC inactivation and down-regulation of cyclin D1 expression. In addition, we evidenced a disruption of the microfilaments and microtubules in a consequence of the treatment. Taken together, the data showed by the first time that alkaloids 1/2 strongly inhibit cell proliferation of hepatocellular carcinoma cells. Therefore, they represent promise antitumor compounds against liver cancer and should be considered for further anticancer in vivo studies. (C) 2015 Elsevier Ltd. All rights reserved. Univ Fed Alfenas, Inst Biomed Sci, BR-37130000 Alfenas, MG, Brazil Univ Fed Uberlandia, Inst Chem, Nucleus Res Nat Prod NuPPeN, BR-38408144 Uberlandia, MG, Brazil State Univ Sao Paulo, Inst Chem, BR-14801970 Araraquara, SP, Brazil Univ Fed Alfenas, Inst Chem, Lab Phytochem & Med Chem LFQM, BR-37130000 Alfenas, MG, Brazil Univ Fed Alfenas, Inst Nat Sci, BR-37130000 Alfenas, MG, Brazil Univ Fed Alfenas, Inst Chem, Lab Res Med Chem PeQuiM, BR-37130000 Alfenas, MG, Brazil State Univ Sao Paulo, Inst Chem, BR-14801970 Araraquara, SP, Brazil CNPq: 454088/2014-0 CNPq: 573564/2008-6 FAPEMIG: CEX-PPM-00241-15 FAPEMIG: APQ-00341-13

Premise of the study: Senna spectabilis var. excelsa (Fabaceae) is a South and Central American tree of great ecological importance and one of the most common species in several sites of seasonally dry forests. Our goal was to develop microsatellite markers to assess the genetic diversity and structure of this species. Methods and Results: We designed and assessed 53 loci obtained from a microsatellite-enriched library and an intersimple sequence repeat library. Fourteen loci were polymorphic, and they presented a total of 39 alleles in a sample of 61 individuals from six populations. The mean values of observed and expected heterozygosities were 0.355 and 0.479, respectively. Polymorphism information content was 0.390 and the Shannon index was 0.778. Conclusions: Polymorphism information content and Shannon index indicate that at least nine of the 14 microsatellite loci developed are moderate to highly informative, and potentially useful for population genetic studies in this species.

Previously we designed a series of pyridinic anticholinesterasic compounds based on molecular hybridization between tacrine and the natural piperidine alkaloid (-)-3-O-acetylspectaline isolated from Senna spectabilis. Based on the information that the cholinergic system has an important role in the treatment of schizophrenia and depression, we herein report the evaluation of a series of pyridinic compounds in animal models for antipsychotic and antidepressant-like activities. Compound 2 decreased the immobility time of mice in the forced swimming test (5 and 10mg/kg p.o.) and prevented the climbing behavior induced by apomorphine (10mg/kg, p.o.), without impairing animals locomotor activity.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:21:40Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:28:14Z : No. of bitstreams: 1 2-s2.0-30844453402.pdf: 215201 bytes, checksum: 7f2543eabc1382652315ce9e6a6284c3 (MD5) Made available in DSpace on 2014-05-27T11:21:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-11-01 The fragmentation pattern of a homologous series of piperidine alkaloids isolated from S. spectabilis was investigated using electrospray ionization tandem mass spectrometry (ESI-MS/MS). The ESI-MS and ESI-MS/MS analyses of EtOH extracts and fractions from flowers and fruits of S. spectabilis allowed to elucidate the structures of four new compounds. The identification of these co-metabolites, based on the fragmentation patterns of previously isolated compounds, and further confirmed by accurate mass spectrometry defines this technique as a powerful tool to determine the metabolomic profile of species which has pharmacological importance. ©2005 Sociedade Brasileira de Química. Instituto de Química Universidade Estadual Paulista, CP 355, 14801-970 Araraquara - SP Núcleo de Pesquisas em Ciências Exatas e Tecnológicas Universidade de Franca, Av. Dr. A. Salles de Oliveira 201, 14404-600 Franca - SP Departamento de Física e Química Faculdade de Ciências Farmacêuticas Universidade de São Paulo, Via do Café s/n, 14040-903 Ribeirão Preto - SP Seção de Fisiologia e Bioquímica de Plantas Instituto de Botânica, CP 4005, 01061-970 São Paulo - SP Instituto de Química Universidade Estadual Paulista, CP 355, 14801-970 Araraquara - SP

We report on an attempt to distinguish cropped from fallowed land and young from old fallow by the rate of decomposition of a standard material, to contribute towards the development of simple, yet reliable indicators of soil quality and agricultural sustainability on tropical soils. In three southern Cameroonian villages, Senna spectabilis leaves and wood were incubated in undisturbed bush fallow of about 4 years, young secondary regrowth of about 12 years and secondary forest of at least 25 years and in the same fallow age class after clearing and cropping. The decomposition of S. spectabilis leaves distinguished fallowed from cropped land throughout a period of 14 to 280 days after incubation, independent of the fallow type that was cleared and the location. Fallow types were distinguished over the same period, with higher leaf mass loss in secondary forest systems than young regrowth and bush fallow. In all cases mass loss followed significant logarithmic functions. Soil chemical properties were not correlated to leaf mass loss. Mass loss from S. spectabilis wood was not suitable to distinguish either undisturbed from cropped or one fallow age class from another. Significant differences between land uses occurred only at the end of the incubation period. Fallow types could not be distinguished from each other. S. spectabilis leaf decomposition may be developed into one component of a soil quality or soil function indicator if decomposition can be linked to crop yields in cleared sites and biomass accumulation in undisturbed sites and other soil properties.

A field experiment was performed in eastern Kenya to estimate N2 fixation by Sesbania sesban over an 18-month period using the 15N dilution method. The influence of three reference species, Senna spectabilis, Eucalyptus saligna and Grevillea robusta, on the estimates of N2 fixation was also assessed. Percentage Ndfa (nitrogen derived from the atmosphere) was calculated based on foliar atom excess (FAE), above-ground atom excess (AAE) or whole tree atom excess (WAE) data. The differences in atom% 15N excess values between species and plant parts are presented and discussed. We recommend the use of several reference species for estimating %Ndfa and that the different results obtained should be carefully considered in relation to the issues being addressed. In this study, Senna was the most suitable of the three reference species because its N uptake pattern and phenology were very similar to those of Sesbania. When well established, the amount of N fixed by Sesbania accounts for more than 80% of its total N content, according to FAE-based estimates. We estimated the Ndfa by Sesbania after 18 months to between 500 and 600 kg ha−1 , depending on whether FAE, AAE or WAE data were used and on the choice of reference species. The substantial accumulation of N in planted Sesbania highlighted its potential to increase the sustainability of crop production on N-limited soils. We consider the 15N dilution method to be appropriate for quantifying N2 fixation in improved fallows in studies, similar to this one, of young trees with high N2-fixing ability.

Five new piperidine alkaloids were designed from natural (−)-3- O -acetyl-spectaline and (−)-spectaline that were obtained from the flowers of Senna spectabilis (sin. Cassia spectabilis , Leguminosae). Two semi-synthetic analogues ( 7 and 9 ) inhibited rat brain acetylcholinesterase, showing IC 50 of 7.32 and 15.1 μM, and were 21 and 9.5 times less potent against rat brain butyrylcholinesterase, respectively. Compound 9 (1 mg/kg, ip) was fully efficacious in reverting scopolamine-induced amnesia in mice. The two active compounds ( 7 and 9 ) did not show overt toxic effects at the doses tested in vivo.

Decline in crop yields is a major problem facing smallholder farmers in Kenya and the entire Sub-Saharan region. This is attributed mainly to the mining of major nutrients due to continuous cropping without addition of adequate external nutrients. In most cases inorganic fertilizers are expensive, hence unaffordable to most smallholder farmers. Although organic nutrient sources are available, information about their potential use is scanty. A field experiment was set up in the sub-humid highlands of Kenya to establish the chemical fertilizer equivalency values of different organic materials based on their quality. The experiment consisted of maize plots to which freshly collected leaves of Tithonia diversifolia (tithonia), Senna spectabilis (senna) and Calliandra calothyrsus (calliandra) (all with %N>3) obtained from hedgerows grown ex situ (biomass transfer) and urea (inorganic nitrogen source) were applied. Results obtained for the cumulative above ground biomass yield for three seasons indicated that a combination of both organic and inorganic nutrient source gave higher maize biomass yield than when each was applied separately. Above ground biomass yield production in maize (t ha−1) from organic and inorganic fertilization was in the order of senna+urea (31.2), tithonia+urea (29.4), calliandra+urea (29.3), tithonia (28.6), senna (27.9), urea (27.4), calliandra (25.9), and control (22.5) for three cumulative seasons. On average, the three organic materials (calliandra, senna and tithonia) gave fertilizer equivalency values for the nitrogen contained in them of 50, 87 and 118%, respectively. It is therefore recommended that tithonia biomass be used in place of mineral fertilizer as a source of nitrogen. The high equivalency values can be attributed to the synergetic effects of nutrient supply, and improved moisture and soil physical conditions of the mulch. However, for sustainable agricultural production, combination with mineral fertilizer would be the best option.

Four common agroforestry trees, including both exotic and native species, were used to provide a range of leafing phenologies to test the hypothesis that temporal complementarity between trees and crops reduces competition for water in agroforestry systems during the cropping period and improves utilisation of annual rainfall. Species examined included Melia volkensii, which sheds its leaves twice a year, Senna spectabilis and Gliricidia sepium, which shed their leaves once during the long dry season, and the evergreen Croton megalocarpus. Phenological patterns were examined in relation to climatic conditions in the bimodal rainfall regions of Kenya to identify factors which dictate the intensity of competition between trees and crops. The main differences in leaf cover patterns were between indigenous and exotic tree species. The Central American species, S. spectabilis and G. sepium, shed their foliage during the dry season before the short rains, whereas the native species, M. volkensii and C. megalocarpus, exhibited reduced leaf cover during both dry seasons. C. megalocarpus was the only species to maintain leaf cover throughout the 2-year experimental period. M. volkensii and S. spectabilis exhibited similar leafing phenology, losing almost all leaf cover during the long dry season (July–October) and flushing before the onset of the ensuing rains. S. spectabilis lost few leaves during the short dry season, whereas M. volkensii shed a greater proportion of its foliage before flushing prior to the long rains (March–July). M. volkensii lost much of its leaf cover during the 1997/1998 short rains (October–February), when soil water content was unusually high. Although essentially evergreen, leaf cover in C. megalocarpus decreased during the dry season and increased rapidly during periods of high rainfall. G. sepium exhibited a period of low leaf cover during the long dry season and did not regain full leaf cover until mid-way through the short rains. The mechanisms responsible for these phenological changes and the implications of tree phenology for resource utilisation and competition with crops are discussed.

The ability of multipurpose hedgerow tree species to out-compete undesired regrowth during fallow phases was examined. Biomass and spatial distribution of grass and broad leaf volunteers was measured after two years of fallow, in two alley cropping systems planted at six m interrow distance, at the Humid Forest Ecoregional Centre Research Station, Mbalmayo, southern Cameroon. The two experiments had been continuously cropped for five and six years previously. In the experiment cropped for six years, the presence of Senna spectabilis [(DC.) Irwin and Barnaby] hedgerows reduced the biomass of the volunteer regrowth from 9.2 to 4.3 Mg ha−1. Tillage during the previous cropping phase increased the broad leaf biomass from 3.0 to 4.4 Mg ha−1, reduced the biomass of grasses from 3.4 to 2.7 Mg ha−1 but had no effect on the total volunteer biomass. Volunteer biomass was significantly lower within 1.5 m of the S. spectabilis hedgerows than at positions further away. In the experiment cropped for five years, S. spectabilis reduced the volunteer regrowth biomass significantly. Two other hedgerow species, Dactyladenia barteri [(Hook f ex Oliv.) Engl.] and Flemingia macrophylla [(Willd.) Merrill] had no effect on the total amount of volunteer regrowth but did reduce volunteer biomass within 0.5 m of the hedgerows. S. spectabilis caused a stronger reduction of volunteer biomass than D. barteri and F. macrophylla at almost all distances from the hedgerows. The competitiveness of D. barteri and F. macrophylla is insufficient and their growth habit is unsuitable to out-compete undesired species in this alley cropping system.

The effect of tree row species on the distribution of soil inorganic N and the biomass growth and N uptake of trees and crops was investigated beneath a Grevillea robustaA. Cunn. ex R. Br. (grevillea) tree row and Senna spectabilisDC. (senna) hedgerow grown with Zea mays L. (maize) and a sole maize crop, during one cropping season. The hypothesis was that a tree with a large nutrient uptake would have a greater competitive effect upon coexisting plants than a tree that takes up less and internally cycles nutrients. The field study was conducted on a kaolinitic Oxisol in the sub-humid highlands of western Kenya. Soil nitrate and ammonium were measured to 300 cm depth and 525 cm distance from the tree rows, before and after maize cropping. Ammonium concentrations were small and did not change significantly during the cropping season. There was > 8 mg nitrate kg−1 in the upper 60 cm and at 90–180 cm depth at the start of the season, except within 300 cm of the senna hedgerow where concentrations were smaller. During the season, nitrate in the grevillea-maize system only decreased in the upper 60 cm, whereas nitrate decreased at almost every depth and distance from the senna hedgerow. Inorganic N (nitrate plus ammonium) decreased by 94 kg ha−1 in the senna-maize system and 33 kg ha−1 in the grevillea-maize system.

Farmer-participatory tests were conducted near Machakos in semi-arid Kenya during 1994–1996 using grevillea (Grevillea robusta) to test the hypothesis that small-scale farmers could meet their needs of fuelwood and poles by boundary plantings of adapted trees. The average tree survival after one year varied from 37 to 84%, and the average height in the first two years ranged from 0.5 to 1 m per year, depending on the seasonal rainfall. The trees did not affect the performance of adjacent crops during the first 18 mo of planting. However, they later reduced crop yields, but only in the first two rows. Of the five tree species tested on the farms, eucalyptus (Eucalyptus camaldulensis) was the fastest growing tree, followed by melia (Melia volkensii), grevillea and senna (Senna spectabilis). Markhamia lutea was not adapted to the semi-arid environment, and the majority of trees of this species died. When farmers evaluated the trees they found grevillea and eucalyptus to be susceptible to termites, a...

Senna spectabilis (DC.) H.S. IrwinBarneby (Fabaceae; Caesalpinioideae), commonly known as "canafístula" or "cassia", is widely used in the semi-arid region of northeastern Brazil as a source of forage and timber. The plant presents a high nutritional content in comparison with other forage species that are native to the Brazilian Caatinga; thus, it represents a valuable resource during periods of drought. The aim of this study was to evaluate the genetic variability among eight accessions of S. spectabilis available in the forage germplasm collection of Embrapa Meio-Norte using the random-amplified polymorphic DNA technique. The 15 primers selected for use in the analysis produced 107 bands, including 59 (55.14%) that were polymorphic. A similarity matrix was generated on the basis of Jaccard coefficients, and a dendrogram was constructed using the unweighted pair group method with arithmetic mean clustering technique. The mean value of the similarity coefficients was 0.73, and the cophenetic correlation coefficient was 83.76%. Accessions CAN. 4 and CAN. 5 presented the greatest genetic similarity, while CAN. 6 and CAN. 8 were the most divergent. The S. spectabilis accessions were classified into two main groups with group I including accessions CAN. 1, CAN. 2, CAN. 4, CAN. 5, CAN. 7, CAN. 8, and CAN. 9, and group II comprising the single accession CAN. 6. The results presented herein revealed that, although the germplasm collection is presently limited, there is sufficient genetic variability among the accessions to permit future breeding programs.

The effects of organic residues and inorganic fertilizers on P availability and maize yield were compared in a Nitisol of western Kenya. Leaf biomass of Calliandra calothyrsus, Senna spectabilis, Croton megalocarpus, Lantana camara, Sesbania sesban, and Tithonia diversifolia were incorporated into the soil at 5 Mg ha–1 for six consecutive seasons in 3 years and responses compared with those following the application of 120 kg N ha–1, 0 kg P ha–1 (0P); 120 kg N ha–1, 10 kg P ha–1; and 120 kg N ha–1 25 kg P ha–1 as urea and triple superphosphate (TSP); K was supplied in all treatments. Addition of Tithonia, Lantana and Croton increased soil resin-extractable P over that of fertilizer-amended soil throughout the first crop, but the amounts in the former treatments became similar to those for soils amended with inorganic fertilizers for subsequent crops. Addition of Sesbania, Calliandra and Senna had a similar effect on resin P as inorganic fertilizers. Total maize yields after six seasons were tripled by the application of Tithonia compared to 0P, and were higher than those of the Calliandra, Senna, Sesbania and Lantana treatments, and similar only to that of the Croton treatment. P recovered in the above-ground biomass and resin P, immediately after the implementation of the treatments, was higher in the Senna, Sesbania, Croton, Lantana and Tithonia (35–77%) treatments than in the inorganic fertilizer treatments (21–27%). The P content of organic residues, and the soluble C:total P ratio, were the main residue parameters predicting soil P availability and maize yield. All organic residues used in this study can replace inorganic fertilizers for the enhancement of P availability and maize production, while an additional benefit could be obtained from the use of Croton, Lantana and Tithonia.

An intercrop of maize and cassava was cultivated for six consecutive years from 1990/91 to 1995/96. This paper reports on crop performance from the fourth to the sixth year in alley cropping with Senna spectabilis and in a no-tree control, with and without tillage. Maize grain yield increased significantly from 1993 to 1994 (P = 0.0032) and from 1994 to 1995 (P = 0.019). Tillage only had a significantly positive effect on maize grain yield in 1993. Alley cropping had no significant effect on maize grain yield in any year. Cassava root yield was neither affected by tillage nor by alley cropping in any year. Neither the cumulative yields over the three years nor the sum of maize grain and cassava root yield were significantly affected by alley cropping or tillage. No significant interactions were found between cropping system and tillage system.

Complementarity in the distribution of tree and crop root systems is important to minimise competition for resources whilst maximising resource use in agroforestry systems. A field study was conducted on a kaolinitic Oxisol in the sub-humid highlands of western Kenya to compare the distribution and dynamics of root length and biomass of a 3-year-old Grevillea robusta A. Cunn. ex R. Br. (grevillea) tree row and a 3-year-old Senna spectabilis DC. (senna) hedgerow grown with Zea mays L. (maize). Tree roots were sampled to a 300 cm depth and 525 cm distance from the tree rows, both before and after maize cropping. Maize roots were sampled at two distances from the tree rows (75–150 cm and 450–525 cm) to a maximum depth of 180 cm, at three developmental stages. The mean root length density (Lrv) of the trees in the upper 15 cm was 0.55 cm cm−3 for grevillea and 1.44 cm cm−3 for senna, at the start of the cropping season. The Lrv of senna decreased at every depth during the cropping season, whereas the Lrv of grevillea only decreased in the crop rooting zone. The fine root length of the trees decreased by about 35% for grevillea and 65% for senna, because of maize competition, manual weeding, seasonal senescence or pruning regime (senna). At anthesis, the Lrv of maize in the upper 15 cm was between 0.8 and 1.5 cm cm−3. Maize root length decreased with greater proximity to the tree rows, potentially reducing its ability to compete for soil resources. However, the specific root length (m g−1) of maize was about twice that of the trees, so may have had a competitive uptake advantage even when tree root length was greater. Differences in maize fine root length and biomass suggest that competition for soil resources and hence fine root length may have been more important for maize grown with senna than grevillea.

Maize/cassava were intercropped between hedgerows of Senna spectabilis [(DC.) Irwin and Barneby], Flemingia macrophylla [(Willd.) Merrill] and Dactyladenia barteri [(Hook f ex Oliv.) Engl.] for five consecutive years on an Ultisol in southern Cameroon. Crop yields and hedgerow biomass production in the third to fifth year of cropping are reported. S. spectabilis produced more biomass than F. macrophylla and D. barteri in all years. Cumulative maize grain and cassava tuber yields were highest in F. macrophylla alley cropping, outyielding the no-tree control consistently by 42 to 67% (average 56%). Between hedgerows of D. barteri and S. spectabilis, crops yielded 17% and 16% more than the no-tree control, respectively. However, between S. spectabilis hedgerows, yields were highly variable between years (−15% to +35% compared to the no-tree control) and thus the system is at risk of failure. F. macrophylla is recommended for continuous alley cropping of maize/cassava intercrop. The use of D. barteri may require fallow phases for biomass accumulation followed by cropping phases with rigorous pruning. Although this may lead to lower cumulative yields, the products of the fallow phase, such as stakes and firewood, may provide some compensation.

Phytochemical work in the search for bioactive metabolites from the methanolic extract of Senna spectabilis green fruits led to the isolation of a new piperidine alkaloid, (+)-3- O-feruloylcassine ( 1), in addition to the known (-)-spectaline ( 2) and (-)-3- O-acetylspectaline ( 3). The isolates were submitted to in vitro evaluation of lipoperoxidation (LPO) and cyclooxygenase enzymes (COX-1 and -2) inhibitory properties and showed moderate antioxidant activities (40-70%) at 100 ppm when compared to commercial standards BHT and vitamin E and moderate inhibition of COX-1 (ca . 40%) and marginal inhibition of COX-2 enzymes (

Indices of shallow rootedness and fractal methods of root system study were combined with sapflow monitoring to determine whether these ‘short-cut’ methods could be used to predict tree competition with crops and complementarity of below ground resource use in an agroforestry trial in semi-arid Kenya. These methods were applied to Grevillea robusta Cunn., Gliricidia sepium (Jacq.) Walp., Melia volkensii Gurke and Senna spectabilis syn. Cassia spectabilis aged two and four years which were grown in simultaneous linear agroforestry plots with maize as the crop species. Indices of competition (shallow rootedness) differed substantially according to tree age and did not accurately predict tree:crop competition in plots containing trees aged four years. Predicted competition by trees on crops was improved by multiplying the sum of proximal diameters squared for shallow roots by diameter at breast height2, thus taking tree size into account. Fractal methods for the quantification of total length of tree root systems worked well with the permanent structural root system of trees but seriously underestimated the length of fine roots (less than 2 mm diameter). Sap flow measurements of individual roots showed that as expected, deep tap roots provided most of the water used by the trees during the dry season. Following rainfall, substantial water uptake by shallow lateral roots occurred more or less immediately, suggesting that existing roots were functioning in the recently wetted soil and that there was no need for new fine roots to be produced to enable water uptake following rainfall.

Efforts to overcome declining soil fertility on small holder farms in western Kenya must be consistent with the reality of low utilization of inorganic fertilizers. Likewise organic inputs alone cannot supply adequate nutrients. The use of two organic resources, Tithonia diversifolia (tithonia) and Senna spectabilis (senna) leaves, and their combination with inorganic P for improving soil fertility and maize yields was investigated on a P limiting soil in Western Kenya. Treatments included: 1) control, no inputs; 2) 5 t ha−1 (dry matter) tithonia leaves; 3) 5 t ha−1 senna leaves; 4) 5 t ha−1 tithonia leaves + 25 kg P ha−1 as triple superphosphate (TSP); 5) 5 t ha−1 senna leaves + 25 kg P ha−1 (as TSP); and 6) 25 kg P ha−1 of TSP. Maize was used as a test crop. Decomposition and P and N release of tithonia and senna leaves were determined in a litterbag study. Tithonia + TSP applications tripled maize yields compared to the control, senna + TSP and tithonia sole application doubled yields, while senna sole applications did not increase yields substantially. A large residual yield was produced in the tithonia treatments in a subsequent crop. These yield results were consistent with the higher quality and faster release of N and P from the tithonia leaves compared to senna. The tithonia biomass transfer system can improve yields in the short term but has limitations because of the large amount of biomass and the associated labor requirements.

Appropriate 15N-labeling methods are crucial for estimating N2-fixation in trees used in agroforestry systems. A 4-year field experiment was conducted on an Alfisol in Southwestern Nigeria to compare the estimates of N2 fixed in Leucaena leucocephala, using two non-N2-fixing leguminous trees, Senna siamea and S. spectabilis, as reference plants and three different methods of introducing 15N into soil. The atom % 15N uptake pattern (as reflected in the leaves) was identical in both N2- and non-N2-fixing tree species irrespective of the 15N-application method. There was a significant decline in atom % 15N excess in the leaves of L. leucocephala (from 0.266 to 0.039), S. siamea (0.625 to 0.121), and S. spectabilis (from 0.683 to 0.118) from the first sampling 12 months after planting and the second sampling 18 months after sampling. From the second harvest in 1991 until the end of the experiment (fifth) harvest in 1993, however, the atom 15N % excess decline in leaves of the three species was less pronounced and depended on the method of 15N application. In those plants to which the tracer was applied once at planting, the 15N decline was steady between the second and the last prunings. In the split-application treatment, the atom 15N % excess increased slightly at the third pruning and decreased during the subsequent two prunings. The reference tree and the method of 15N application influenced the estimated proportion of N derived from atmospheric N2 by L. leucocephala, calculated as 73 and 64%, corresponding to 119 and 98 kg N ha-1 of N2 fixed per 6 months, when S. spectabilis and S. siamea were used as reference trees, respectively. The approach by which 15N-labeled fertilizer was applied to the soil in three splits gave slightly higher estimates of N derived from the atmosphere but this was of little agronomic significance because total N2 fixed was similar for all methods.