Microbiome properties in the root nodules of Prosopis cineraria, a leguminous desert tree.

We conducted a comprehensive analysis of the total microbiome and transcriptionally active microbiome communities in the roots and root nodules of Prosopis cineraria, an important leguminous tree in arid regions of many Asian countries. Mature P. cineraria trees growing in the desert did not exhibit any detected root nodules. However, we observed root nodules on the roots of P. cineraria growing on a desert farm and on young plants growing in a growth chamber, when inoculated with rhizosphere soil, including with rhizosphere soil from near desert tree roots that had no nodules. Compared to nearby soil, non-nodulated roots were enriched with Actinobacteria (e.g., Actinophytocola sp.), whereas root nodules sampled from the desert farm and growth chamber had abundant Alphaproteobacteria (e.g., Ensifer sp.). These nodules yielded many microbes in addition to such nitrogen-fixing bacteria as Ensifer and Sinorhizobium species. Significant differences exist in the composition and abundance of microbial isolates between the nodule surface and the nodule endosphere. Shotgun metagenome analysis of nodule endospheres revealed that the root nodules comprised over 90% bacterial DNA, whereas metatranscriptome analysis showed that the plant produces vastly more transcripts than the microbes in these nodules. Control inoculations demonstrated that four out of six Rhizobium, Agrobacterium, or Ensifer isolates purified from P. cineraria nodules produced nodules in the roots of P. cineraria seedlings under greenhouse conditions. The best nodulation was achieved when seedlings were inoculated with a mixture of those bacterial strains. Though root nodulation could be achieved under water stress conditions, nodule number and nodule biomass increased with copious water availability. .IMPORTANCEMicrobial communities were investigated in roots and root nodules of Prosopis cineraria, a leguminous tree species in arid Asian regions that is responsible for exceptionally important contributions to soil fertility in these dramatically dry locations. Soil removed from regions near nodule-free roots on these mature plants contained an abundance of bacteria with the genetic ability to generate nodules and fix nitrogen but did not normally nodulate in their native rhizosphere environment, suggesting a very different co-evolved relationship than that observed for herbaceous legumes. The relative over-expression of the low-gene-density plant DNA compared to the bacterial DNA in the nodules was also unexpected, indicating a very powerful induction of host genetic contributions within the nodule. Finally, the water dependence of nodulation in inoculated seedlings suggested a possible link between early seedling growth (before a deep root system can be developed) and the early development of nitrogen-fixing capability.

The radiation of nodulated Chamaecrista species from the rainforest into more diverse habitats has been accompanied by a reduction in growth form and a shift from fixation threads to symbiosomes.

All non-mimosoid nodulated genera in the legume subfamily Caesalpinioideae confine their rhizobial symbionts within cell wall-bound "fixation threads" (FTs). The exception is the large genus Chamaecrista in which shrubs and subshrubs house their rhizobial bacteroids more intimately within symbiosomes, whereas large trees have FTs. This study aimed to unravel the evolutionary relationships between Chamaecrista growth habit, habitat, nodule bacteroid type, and rhizobial genotype. The growth habit, bacteroid anatomy, and rhizobial symbionts of 30 nodulated Chamaecrista species native to different biomes in the Brazilian state of Bahia, a major centre of diversity for the genus, was plotted onto an ITS-TrnL-F-derived phylogeny of Chamaecrista. The bacteroids from most of the Chamaecrista species examined were enclosed in symbiosomes (SYM-type nodules), but those in arborescent species in the section Apoucouita, at the base of the genus, were enclosed in cell wall material containing homogalacturonan (HG) and cellulose (FT-type nodules). Most symbionts were Bradyrhizobium genotypes grouped according to the growth habits of their hosts, but the tree, C. eitenorum, was nodulated by Paraburkholderia. Chamaecrista has a range of growth habits that allow it to occupy several different biomes and to co-evolve with a wide range of (mainly) bradyrhizobial symbionts. FTs represent a less intimate symbiosis linked with nodulation losses, so the evolution of SYM-type nodules by most Chamaecrista species may have (a) aided the genus-wide retention of nodulation, and (b) assisted in its rapid speciation and radiation out of the rainforest into more diverse and challenging habitats.

Genome Report: Chromosome-level genome of the transformable northern wattle, Acacia crassicarpa.

The genus Acacia is a large group of woody legumes containing an enormous amount of morphological diversity in leaf shape. This diversity is at least in part the result of an innovation in leaf development where many Acacia species are capable of developing leaves of both bifacial and unifacial morphology. While not unique in the plant kingdom, unifaciality is most commonly associated with monocots, and its developmental genetic mechanisms have yet to be explored beyond this group. Here we identify an accession of Acacia crassicarpa with high regeneration rates, and isolate a clone for genome sequencing. We generate a chromosome level assembly of this readily transformable clone and using comparative analyses confirm a whole genome duplication unique to Caesalpinoid legumes. This resource will be important for future work examining genome evolution in legumes and the unique developmental genetic mechanisms underlying unifacial morphogenesis in Acacia.

Ethnomedical Applications and Conservation Status of Leguminosae- Caesalpinioideae Plants in Uttar Pradesh, India.

BACKGROUND: This review highlights the folklore, ethnomedicinal uses and conservation status of Caesalpinioideae in Uttar Pradesh (India). AIMS: It aims at compiling available data on traditional medicine, biological activity, phytochemical information and assessing the regional red list status of Caesalpinioideae in Uttar Pradesh. The information provided would help in formulating new drugs and medicines and addressing global conservation issues of such medicinally exploited species. METHODS: The current study included an extensive and systematic review of available literature, the study of previous collections of herbarium specimens, random interviews with locals and tribals, field surveys, and GeoCAT tool-based assessment during 2016-2020. The study reports that the majority of species of Caesalpinioideae are used for curing digestive problems (about 20 species) and skin diseases (19 species). RESULTS: Almost all the species have antimicrobial and antioxidant properties. These pharmacological activities can be attributed to the presence of various types of anthraquinones in plants. CONCLUSION: The regional conservation status reveals that eight species qualified for the status of regionally threatened category while two species fall under the near threatened category.

The complete chloroplast genome of Mimosa pigra L. (Fabaceae), a notorious invasive plant.

Mimosa pigra L., also called the giant sensitive tree, is native to tropical America and has invaded Africa, Asia, and Australia. Here, we report the complete chloroplast genome of M. pigra, which was 165,996 bp in length and composed of a large single-copy region (LSC; 93,299 bp), a small single-copy region (SSC; 17,989 bp) and two inverted repeat regions (IRs; 27,354 bp). The complete M. pigra chloroplast genome included 83 protein-coding genes, 37 tRNAs and 8 rRNAs. Phylogenetic analysis using the maximum likelihood method revealed the monophyly of M. pigra and related taxa of the subfamily Caesalpinioideae. In comparison, the members of Papilionoideae were paraphyletic.

Cross-species transcriptomes reveal species-specific and shared molecular adaptations for plants development on iron-rich rocky outcrops soils.

BACKGROUND: Canga is the Brazilian term for the savanna-like vegetation harboring several endemic species on iron-rich rocky outcrops, usually considered for mining activities. Parkia platycephala Benth. and Stryphnodendron pulcherrimum (Willd.) Hochr. naturally occur in the cangas of Serra dos Carajás (eastern Amazonia, Brazil) and the surrounding forest, indicating high phenotypic plasticity. The morphological and physiological mechanisms of the plants' establishment in the canga environment are well studied, but the molecular adaptative responses are still unknown. To understand these adaptative responses, we aimed to identify molecular mechanisms that allow the establishment of these plants in the canga environment. RESULTS: Plants were grown in canga and forest substrates collected in the Carajás Mineral Province. RNA was extracted from pooled leaf tissue, and RNA-seq paired-end reads were assembled into representative transcriptomes for P. platycephala and S. pulcherrimum containing 31,728 and 31,311 primary transcripts, respectively. We identified both species-specific and core molecular responses in plants grown in the canga substrate using differential expression analyses. In the species-specific analysis, we identified 1,112 and 838 differentially expressed genes for P. platycephala and S. pulcherrimum, respectively. Enrichment analyses showed that unique biological processes and metabolic pathways were affected for each species. Comparative differential expression analysis was based on shared single-copy orthologs. The overall pattern of ortholog expression was species-specific. Even so, we identified almost 300 altered genes between plants in canga and forest substrates with conserved responses in the two species. The genes were functionally associated with the response to light stimulus and the circadian rhythm pathway. CONCLUSIONS: Plants possess species-specific adaptative responses to cope with the substrates. Our results also suggest that plants adapted to both canga and forest environments can adjust the circadian rhythm in a substrate-dependent manner. The circadian clock gene modulation might be a central mechanism regulating the plants' development in the canga substrate in the studied legume species. The mechanism may be shared as a common mechanism to abiotic stress compensation in other native species.

A natural hybrid of Sindora (Fabaceae, Detarioideae) from Singapore.

Sindora×changiensis L.M.Choo, Loo, W.F.Ang & K.Er is a new hybrid from the subfamily Detarioideae in Fabaceae. This is the first reported instance of natural hybridisation in Sindora. Based on population genetics analyses using ddRAD and morphological observations, this taxon represents a fertile hybrid between Sindoracoriacea and Sindoraechinocalyx. This new hybrid is so far only known to occur naturally from Changi at the north-eastern coast of Singapore. It has pods that are sparsely spiny. This is intermediate between the smooth, non-spiny pods of S.coriacea, and the densely spiny pods of S.echinocalyx. The calyx is smooth and unarmed, resembling S.coriacea. Last but not least, the ovary is entirely pubescent, different from S.coriacea and S.echinocalyx. The ovary of S.coriacea has a glabrous patch in the middle, while that of S.echinocalyx has minute spines protruding from the dense pubescence. A taxonomic description and an updated key to the Sindora of Singapore and Peninsular Malaysia are also provided.

Misleading fruits: The non-monophyly of Pseudopiptadenia and Pityrocarpa supports generic re-circumscriptions and a new genus within mimosoid legumes.

Generic delimitation in Piptadenia and allies (mimosoid legumes) has been in a state of flux, particularly caused by over-reliance on fruit and seed morphology to segregate species out of Piptadenia into the genera Parapiptadenia, Pityrocarpa and Pseudopiptadenia. Although supporting their segregation from Piptadenia, previous phylogenetic analyses suggested that some of these segregated genera are not monophyletic. Here, we test the monophyly of Parapiptadenia, Pityrocarpa and Pseudopiptadenia with dense taxon sampling across these genera, including the type species of each genus. Our analysis recovers Parapitadenia as monophyletic, but places Pseudopiptadenia species in two distinct lineages, one of which includes all three species of Pityrocarpa. Given that the type species of both Pseudopiptadenia and Pityrocarpa are nested in the same clade, we subsume Pseudopiptadenia under the older name Pityrocarpa. The remaining Pseudopiptadenia species are assigned to the new genus Marlimorimia. Alongside high molecular phylogenetic support, recognition of Parapiptadenia, Pityrocarpa and Marlimorimia as distinct genera is also supported by combinations of morphological traits, several of which were previously overlooked.

Chemical and Biological Evaluation of Amazonian Medicinal Plant Vouacapoua americana Aubl.

Vouacapoua americana (Fabaceae) is an economically important tree in the Amazon region and used for its highly resistant heartwood as well as for medicinal purposes. Despite its frequent use, phytochemical investigations have been limited and rather focused on ecological properties than on its pharmacological potential. In this study, we investigated the phytochemistry and bioactivity of V. americana stem bark extract and its constituents to identify eventual lead structures for further drug development. Applying hydrodistillation and subsequent GC-MS analysis, we investigated the composition of the essential oil and identified the 15 most abundant components. Moreover, the diterpenoids deacetylchagresnone (1), cassa-13(14),15-dien-oic acid (2), isoneocaesalpin H (3), (+)-vouacapenic acid (4), and (+)-methyl vouacapenate (5) were isolated from the stem bark, with compounds 2 and 4 showing pronounced effects on Methicillin-resistant Staphylococcus aureus and Enterococcus faecium, respectively. During the structure elucidation of deacetylchagresnone (1), which was isolated from a natural source for the first time, we detected inconsistencies regarding the configuration of the cyclopropane ring. Thus, the structure was revised for both deacetylchagresnone (1) and the previously isolated chagresnone. Following our works on Copaifera reticulata and Vatairea guianensis, the results of this study further contribute to the knowledge of Amazonian medicinal plants.

Dewerin and gilbertionol two new secondary metabolites from the stem bark of Gilbertiodendron dewevrei (De Wild) J. Leonard.

The phytochemical investigation of the methanol extract of the stem bark of Gilbertiodendron dewevrei led to the isolation of two new secondary metabolites, 5,7-dihydroxy-4'-methoxyisoflavan-2,4-dione (1) and 23-hydroxy-2-tricosanone (2) along with 19 known compounds (3-21). The structure of these compounds were established by interpretation of their spectral data, mainly HR-TOFESIMS, 1 D NMR (1H, 13C and DEPT) and 2 D NMR (1H-1H COSY, HSQC, HMBC, and NOESY), and by comparison with those reported in the literature. The methanol extract and some isolates were screened for their antiradical, antibacterial, and inhibitory properties against acetylcholinesterase.

Phytochemistry and poisoning in ruminants by Enterolobium contortisiliquum (Vell.) Morong (Fabaceae): A systematic review.

Enterolobium contortisiliquum (Vell.) Morong (Fabaceae) is a plant widely distributed in several regions of Brazil, occurring in the phytogeographic domains of Atlantic Forest, Cerrado, and Caatinga. Cases of serious poisoning in cattle, goats, and sheep in the country caused by the ingestion of beans of this species have been reported by several studies. The present work aimed to carry out a systematic review of cases of poisoning by E. contortisiliquum in ruminants and list the main chemical compounds isolated from this plant. For this, searches were performed in the Google Academic, PubMed®, ScienceDirect®, and SciELO databases. A total of 26 articles published in the last 20 years (2001-2021) were included. Studies on cases of natural and experimental poisoning indicate that this species mainly causes photosensitization, abortions, digestive problems, and acute ruminal lactic acidosis in animals that ingest the pods of the plant. The main chemical compounds that occur in the species belong to the triterpene saponins, monoterpene, phenylpropene, and triterpene classes. It is likely that triterpene saponins isolated from E. contortisiliquum are associated with reported cases of photosensitization in cattle. New studies must be conducted to assess the mechanisms of action of chemical compounds isolated from this species in in vivo systems.

Plastome evolution in the Caesalpinia group (Leguminosae) and its application in phylogenomics and populations genetics.

MAIN CONCLUSION: The chloroplast genomes of Caesalpinia group species are structurally conserved, but sequence level variation is useful for both phylogenomic and population genetic analyses. Variation in chloroplast genomes (plastomes) has been an important source of information in plant biology. The Caesalpinia group has been used as a model in studies correlating ecological and genomic variables, yet its intergeneric and infrageneric relationships are not fully solved, despite densely sampled phylogenies including nuclear and plastid loci by Sanger sequencing. Here, we present the de novo assembly and characterization of plastomes from 13 species from the Caesalpinia group belonging to eight genera. A comparative analysis was carried out with 13 other plastomes previously available, totalizing 26 plastomes and representing 15 of the 26 known Caesalpinia group genera. All plastomes showed a conserved quadripartite structure and gene repertoire, except for the loss of four ndh genes in Erythrostemon gilliesii. Thirty polymorphic regions were identified for inter- or intrageneric analyses. The 26 aligned plastomes were used for phylogenetic reconstruction, revealing a well-resolved topology, and dividing the Caesalpinia group into two fully supported clades. Sixteen microsatellite (cpSSR) loci were selected from Cenostigma microphyllum for primer development and at least two were cross-amplified in different Leguminosae subfamilies by in vitro or in silico approaches. Four loci were used to assess the genetic diversity of C. microphyllum in the Brazilian Caatinga. Our results demonstrate the structural conservation of plastomes in the Caesalpinia group, offering insights into its systematics and evolution, and provides new genomic tools for future phylogenetic, population genetics, and phylogeographic studies.

Implication of scanning electron microscopy in the seed morphology with special reference to three subfamilies of Fabaceae.

The current research work was aimed to determine the morphological variation in the seeds of subfamilies Caesalpinioideae, Mimosoideae, and Papilionoideae using scanning electron microscope to investigate the different seed features including; Seed length, width, weight, hilum shape, position, fracture line pattern, pleurogram shape, texture crudeness, ornamentation wall, and surface ornamentation. A total of 12 species were collected. The study reveals that the seed types alters from psilate to rugose, pleurogram shape from lunar to U shape, hilum shape from elliptical to depressed, hilum position from terminal to subterminal, fracture line pattern from reticulate irregular ridges to psilate with regular ridges, texture crudeness from fine to coarse, surface ornamentation from reticulate to psilate, and ornamentation wall also varies from thin to thick. In all the studied species, it was found that seed surface was brown in color except in Senna alata, in which seed surface was black. Regarding the seed size, it was found that the smallest seed was observed for Sesbania sesban, while the largest seed was observed for Pongamia pinnata. The present research article indicates the taxonomic significance of seed morphology in the subfamilies Caesalpinioideae, Mimosaceae, and Papilionoideae.

Queiroziella gen. nov., a new genus of jumping plant-lice (Hemiptera, Psyllidae) from Southern Brazil associated with Mimosa scabrella (Leguminosae).

Queiroziella gen. nov., a new genus of Psylloidea (Psyllidae, Ciriacreminae), is erected for five new species developing on the multipurpose tree Mimosa scabrella (Leguminosae, Caesalpinioideae, mimosoid clade): viz. Queiroziella erato sp. nov., Q. euterpe sp. nov., Q. melpomone sp. nov., Q. terpsichore sp. nov. and Q. thalia sp. nov. Another species from Paraguay, associated with an unidentified Mimosa species, is transferred to the new genus as Queiroziella borealis (Burckhardt, 1987), comb. nov., from Zonopelma (Aphalaroidinae). The new taxa are diagnosed, described and illustrated, and keys are provided for the identification of adults and immatures. Morphologically, Queiroziella resembles Heteropsylla which is also associated with mimosoid legumes and with which it may be closely related. As their host, the new species are restricted to Southern Brazil. Queiroziella euterpe, Q. melpomone and Q. terpsichore are reported from the states of Paraná, Rio Grande do Sul, Santa Catarina and São Paulo, Q. thalia from Paraná and São Paulo, and Q. erato from Paraná. No clear phenological patterns were found though it seems that high psyllid populations coincide with new flush of the host plants. Despite that the psyllids occur sometimes in very high numbers, no visible damage could be detected on host trees. On the other hand, the honeydew of the psyllids may provide a food source for honey-bees during non-flowering periods of Mimosa scabrella.

Chemical constituents of the leaves of Anthonotha macrophylla (Leguminosae).

The present study deals with the isolation and the characterization of the chemical constituents from the leaves of Anthonotha macrophylla (Leguminosae). Using various chromatographic techniques (TLC, CC, HPLC), the methanolic extract of the leaves of Anthonotha macrophylla yielded one new alkaloid (1) as well as six known compounds amongst which an alkane (2), isolated for the first time from a natural product, an ester of fatty acid (3), two isocoumarines (4-5), a sterol (6) and a disaccharide (7). Their structures were elucidated using spectroscopic technics including extensive 1-D and 2-D NMR, HR-SM experiments.

Cytotoxic components from the leaves of Erythrophleum fordii induce human acute leukemia cell apoptosis through caspase 3 activation and PARP cleavage.

Cassaine diterpenoids as erythrofordins A-C (1-3), pseudo-erythrosuamin (4), and erythrofordin U (5) isolated from the leaves of Vietnamese Erythrophleum fordii Oliver were tested cytotoxic activity against human leukemia cancer cells. The results showed that these metabolites exhibited dose-dependent cytotoxicity against human leukemia HL-60 and KG cells with IC50 values ranging from 15.2 ± 1.5 to 42.2 ± 3.6 µM. Treatment with erythrofordin B led to the apoptosis of HL-60 and KG cells due to the activation of caspase 3, caspase 9, and poly (ADP-ribose) polymerase (PARP). Erythrofordin B significantly increased Bak protein expression, but downregulated the anti-apoptotic protein Bcl-2, in HL-60 cells. In silico results demonstrated that erythrofordin B can bind to both the procaspase-3 allosteric site and the PARP-1 active site, with binding energies of -7.36 and -10.76 kcal/mol, respectively. These results indicated that the leaves of Vietnamese E. fordii, which contain cassaine diterpenoids, can induce the apoptosis of human leukemia cancer cells.

The complete plastid genome of Delonix regia (Hook.) Raf. (Leguminosae).

Delonix regia, a plant species of the legume family native to Madagascar, has been widely cultivated in the tropical and subtropical regions as an ornamental tree due to its remarkable showy orange-red flowers over summer. Here we report for the first time the complete plastid genome of this species, which has a typical circular structure with a total length of 162,756 bp and contains two inverted repeat regions (IRs, 25,544 bp), a large single copy region (LSC, 92,490 bp), and a small single copy region (SSC, 19,178 bp). The phylogenetic analysis based on the complete plastome sequences of this species and those of the related species from GenBank strongly suggested that D. regia is nested in the subfamily Caesalpinioideae and is sister to a clade consisting of Erythrophlium fordii and the old-sense Mimosoideae.

Hybrid capture of 964 nuclear genes resolves evolutionary relationships in the mimosoid legumes and reveals the polytomous origins of a large pantropical radiation.

PREMISE: Targeted enrichment methods facilitate sequencing of hundreds of nuclear loci to enhance phylogenetic resolution and elucidate why some parts of the "tree of life" are difficult (if not impossible) to resolve. The mimosoid legumes are a prominent pantropical clade of ~3300 species of woody angiosperms for which previous phylogenies have shown extensive lack of resolution, especially among the species-rich and taxonomically challenging ingoids. METHODS: We generated transcriptomes to select low-copy nuclear genes, enrich these via hybrid capture for representative species of most mimosoid genera, and analyze the resulting data using de novo assembly and various phylogenomic tools for species tree inference. We also evaluate gene tree support and conflict for key internodes and use phylogenetic network analysis to investigate phylogenetic signal across the ingoids. RESULTS: Our selection of 964 nuclear genes greatly improves phylogenetic resolution across the mimosoid phylogeny and shows that the ingoid clade can be resolved into several well-supported clades. However, nearly all loci show lack of phylogenetic signal for some of the deeper internodes within the ingoids. CONCLUSIONS: Lack of resolution in the ingoid clade is most likely the result of hyperfast diversification, potentially causing a hard polytomy of six or seven lineages. The gene set for targeted sequencing presented here offers great potential to further enhance the phylogeny of mimosoids and the wider Caesalpinioideae with denser taxon sampling, to provide a framework for taxonomic reclassification, and to study the ingoid radiation.

Seed germination and early seedling survival of the invasive species Prosopis juliflora (Fabaceae) depend on habitat and seed dispersal mode in the Caatinga dry forest.

BACKGROUND: Biological invasion is one of the main threats to tropical biodiversity and ecosystem functioning. Prosopis juliflora (Sw) DC. (Fabales: Fabaceae: Caesalpinioideae) was introduced in the Caatinga dry forest of Northeast Brazil at early 1940s and successfully spread across the region. As other invasive species, it may benefit from the soils and seed dispersal by livestock. Here we examine how seed dispersal ecology and soil conditions collectively affect seed germination, early seedling performance and consequently the P. juliflora invasive potential. METHODS: Seed germination, early seedling survival, life expectancy and soil attributes were examined in 10 plots located across three habitats (flooding plain, alluvial terrace and plateau) into a human-modified landscape of the Caatinga dry forest (a total of 12,000 seeds). Seeds were exposed to four seed dispersal methods: deposition on the soil surface, burial in the soil, passed through cattle (Boss taurus) digestive tracts and mixed with cattle manure and passed through mule (Equus africanus asinus × Equus ferus caballus) digestive tracts and mixed with mule manure. Seeds and seedlings were monitored through a year and their performance examined with expectancy tables. RESULTS: Soils differed among habitats, particularly its nutrient availability, texture and water with finely-textured and more fertile soils in the flooding plain. Total seed germination was relatively low (14.5%), with the highest score among seeds buried in the flooding plain (47.4 ± 25.3%). Seed dispersal by cattle and mule also positively impacted seed germination. Early seedling survival rate of P. juliflora was dramatically reduced with few seedlings still alive elapsed a year. Survival rate was highest in the first 30 days and declined between 30 and 60 days with stabilization at 70 days after germination in all seed treatments and habitats. However, survival and life expectancy were higher in the flooding plain at 75 days and lower in the plateau. Prosopis juliflora seedling survival and life expectancy were higher in the case seeds were mixed with cattle manure. SYNTHESIS: Prosopis juliflora seeds and seedlings are sensitive to water stress and habitat desiccation. Therefore, they benefit from the humid soils often present across human-disturbed flooding plains. This plant also benefits from seed deposition/dispersal by livestock in these landscapes, since cattle manure represents a nutrient-rich and humid substrate for both seeds and seedlings. The quality of the seed dispersal service varies among livestock species, but this key mutualism between exotic species is due to the arillate, hard-coated and palatable seeds. Prosopis juliflora traits allow this species to take multiple benefits from human presence and thus operating as a human commensal.

Cassaine Diterpenoid Amide from Stem Bark of Erythrophleum fordii Suppresses Cytotoxic and Induces Apoptosis of Human Leukemia Cells.

Cassaine diterpenoids amides from the stem bark of Vietnamese Erythrophleum fordii Oliver were screened for their cytotoxic activity against human cancer cells. The cell proliferation assay results showed that, among the active compounds, 3ß-acetyl-nor-erythrophlamide (3AEP) exhibited the most potential cytotoxicity against human leukemia HL-60 and KG cells with IC50 values of 12.0 ± 1.2 and 18.1 ± 2.7 µM, respectively. Treatment of 3AEP resulted in the apoptosis of HL-60 cells via the activation of caspase 3, and poly (ADP-ribose) polymerase (PARP). Molecular docking in silico results showed that the 3AEP can bind to both the procaspase-3 allosteric site and the PARP-1 active site, with binding energies of -7.51 and -9.63 kcal/mol respectively. These results indicated that the stem bark of Vietnamese E. fordii and its cassaine diterpenoid amides may be useful in the apoptosis induction of human leukemia cancer cells.