Explore the vast range of titles available.

We conducted this study to understand the dynamics of revegetation by examining the levels of mineral nitrogen (NO₃⁻ and NH₄⁺) in soil and the capacity of nitrogen use by the principal species growing in secondary forest in central Amazonia. For this, we measured the nitrate and ammonium content of soil, leaves and xylem sap, nitrate reductase activity of the leaves and free amino acid contents of the xylem sap in five tree species (Vismia cayennensis, Vismia japurensis, Bellucia dichotoma, Laetia procera and sap in five tree species (Vismia cayennensis, Vismia japurensis, Bellucia dichotoma, Laetia procera and Goupia glabra) over a chronosequence during recovery after pasture abandonment at two seasons. Soil ammonium was higher in the dry season and nitrate higher in the wet season and increased these with pasture abandonment age. V. japurensis, B. dichotoma and G. glabra decreased foliar ammonium due to pasture abandonment in the dry season and foliar ammonium increased in L. procera in the wet season. V. japurensis and V. cayennensis showed a decrease in nitrate reductase activity, while B. dichotoma and L. procera showed an increase. Xylem nitrate decreased in L. procera and B. dichotoma in the dry and wet seasons, respectively, and ammonium increased only in V. japurensis and V. cayennensis in the wet. Xylem arginine increased in all plant species after a period of pasture abandonment (except B. dichotoma). Tree species growing in pasture abandoned areas didn’t show the same pattern of use of nitrogen, and this can be important in order to understand the nitrogen metabolism of trees in the Amazon region during forest restoration.

In folk medicine, Vismia guianensis is used to treat skin diseases and mycoses in the Amazon region. We evaluated the anti-Candida activity of the hydroalcoholic extract from the leaves of Vismia guianensis (EHVG). HPLC-PDA and FIA-ESI-IT-MSn were used to chemically characterize EHVG. The anti-Candida activity was determined in vitro by the minimum inhibitory concentrations (MIC) against Candida glabrata (ATCC-2001); Candida albicans (ATCC-90028, ATCC-14053, and ATCC-SC5314), and C. albicans clinical isolates. EHVG effects on adhesion, growth, and biofilm formation were also determined. Molecular docking was used to predict targets for EHVG compounds. The main compounds identified included anthraquinone, vismione D, kaempferol, quercetin, and vitexin. EHVG was fungicidal against all tested strains. C. albicans ATCC 14053 and C. glabrata ATCC 2001 were the most sensitive strains, as the extract inhibited their virulence factors. In silico analysis indicated that vismione D presented the best antifungal activity, since it was the most effective in inhibiting CaCYP51, and may act as anti-inflammatory and antioxidant agent, according to the online PASS prediction. Overall, the data demonstrate that EHVG has an anti-Candida effect by inhibiting virulence factors of the fungi. This activity may be related to its vismione D content, indicating this compound may represent a new perspective for treating diseases caused by Candida sp.

Background/Objectives: Vismia guianensis is a vegetal species popularly used to treat fungal infections. This study evaluated the anti-Candida effect of V. guianensis extract after C. albicans lethal infection in Tenebrio molitor larvae and mice. Methods and Results: The chemical profile analysis of a hydroethanolic extract of the leaves of V. guianensis (EHVG) identified 14 compounds. Two sets of experiments used T. molitor larvae. To evaluate toxicity, the uninfected larvae were treated with EHVG or anthraquinone. We considered the following groups: the controls received PBS; ANFO B received amphotericin B (600 mg/mL); EHVG received the extract; and ANTQ received anthraquinone. The extract and anthraquinone resulted in low-level toxicity in the T. molitor larvae. Another set of experiments evaluated the EHVG effect during lethal infection with Candida albicans. The T. molitor larvae were treated intracelomically (ic/10 μL). Treatment with EHVG efficiently improved the survival of the larvae after lethal infection (60%), probably due to the reduction in CFUs. In the mice, the antifungal effect of EHVG was determined in three groups of immunosuppressed Swiss mice (cyclophosphamide, 50 mg/kg/ip) infected with C. albicans (1 × 107 CFU/ip). The control animals were infected and untreated; the ANFO B animals were infected and treated with amphotericin B (600 µg/kg/ip); and the EHVG animals were infected and treated with the extract (5 mg/kg/orally). A SHAM group (uninfected and untreated) was also included. Survival was assessed for 5 days. The extract increased the mice’s survival (60%) and life expectancy, reducing the CFU counts in the peritoneum and blood. EHVG also increased the number of blood neutrophils and peritoneal macrophages. These systemic activities are likely associated with the presence of flavonoids in the extract. Conclusions: The beneficial effects of EHVG in lethal sepsis are related to an antifungal effect, with the number of CFUs decreasing in the larvae and the mice. In addition, EHVG showed immunological activity in the mice, considering immune cell distribution and cytokine production.

Data papers and open databases have revolutionized contemporary science, as they provide the long-needed incentive to collaborate in large international teams and make natural history information widely available. Nevertheless, most data papers have focused on species occurrence or abundance, whereas interactions have received much less attention. To help fill this gap, we have compiled a georeferenced data set of interactions between 93 bat species of the family Phyllostomidae (Chiroptera) and 501 plant species of 68 families. Data came from 169 studies published between 1957 and 2007 covering the entire Neotropical Region, with most records from Brazil (34.5% of all study sites), Costa Rica (16%), and Mexico (14%). Our data set includes 2571 records of frugivory (75.1% of all records) and nectarivory (24.9%). The best represented bat genera are Artibeus (28% of all records), Carollia (24%), Sturnira (10.1%), and Glossophaga (8.8%). Carollia perspicillata (187), Artibeus lituratus (125), Artibeus jamaicensis (94), Glossophaga soricina (86), and Artibeus planirostris (74) were the bat species with the broadest diets recorded based on the number of plant species. Among the plants, the best represented families were Moraceae (17%), Piperaceae (15.4%), Urticaceae (9.2%), and Solanaceae (9%).Plants of the genera Cecropia (46), Ficus (42), Piper (40), Solanum (31), and Vismia (27) exhibited the largest number of interactions. These data are stored as arrays (records, sites, and studies) organized by logical keys and rich metadata, which helped to compile the information on different ecological and geographic scales, according to how they should be used. Our data set on bat–plant interactions is by far the most extensive, both in geographic and taxonomic terms, and includes abiotic information of study sites, as well as ecological information of plants and bats. It has already facilitated several studies and we hope it will stimulate novel analyses and syntheses, in addition to pointing out important gaps in knowledge. Data are provided under the Creative Commons Attribution 4.0 International License. Please cite this paper when the data are used in any kind of publication related to research, outreach, and teaching activities.

Questions: Secondary succession in the tropics can follow alternative pathways. Land-use history is known to engender alternative successional communities, but the underlying mechanisms driving and sustaining divergence remain unclear. In this study we aim to answer the following questions: (1) does previous land use act as a filter for species composition in secondary forests; and (2) what are the relative roles of management practices, soil properties and landscape composition in determining species composition? Location: Central Amazon, Brazil. Methods: We sampled trees, shrubs and palms (≥1cm diameter) in 38 early secondary forests (5 yr after abandonment) located along gradients of land-use intensity in five shifting cultivation landscapes. We measured the diameter and height of each sampled plant, identified it to species or morpho-species level and checked if it was resprouting or not. At each secondary forest we also collected soil samples for chemical and physical analyses and estimated the amount of old-growth forest surrounding it (landscape composition). Results: We found that previous land-use intensity determined species composition. With increasing land-use intensity, management practices of cut-andburn and associated reduction in soil quality filtered out seed-dependent species and favoured strong sprouters and species that can cope with low nutrient availability. Landscape composition had a weak effect on species assemblages. We found specific species assemblages and indicator species associated with different levels of previous land-use intensity. As a consequence of these local filters, species α- and β-diversity decreased and therefore early successional communities became more similar to each other. Conclusion: Species composition of successional forests is strongly determined by different land-use intensities. Dispersal limitation has a limited effect on determining the composition of the dominant species. Filtering effects of management practices and soil quality determine the species dominating the canopy at early stages of succession and narrow down the range of species able to colonize and establish. This study highlights how land use shapes successional communities and suggests that alternative successional pathways are determined at early stages of succession. Therefore, accounting for land-use history is crucial to improve the understanding of tropical secondary succession. We present a list of indicator species for different levels of previous land-use intensity that can be used to support conservation and restoration decisions in the Amazon.

This work investigates the incorporation of Vismia guianensis alcoholic extract (EAVG) into cassava starch, with the aim of improving its bioplastic properties. Cassava starch was dissolved into distilled water and doped with 0.2%, 0.5%, and 1.0% EAVG under a temperature controlled at the gelatinization point (∼70 °C) and then cast to form bioplastics. The resulting samples were characterized via attenuated total reflectance/Fourier transform infrared spectroscopy (ATR/FTIR), thermogravimetric and differential thermal analysis (TGA-DTA), X-ray diffraction (XRD), scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS), atomic force microscopy (AFM), and mechanical essays, providing insights into chemical composition, thermal stability, crystallinity, surface morphology, and mechanical properties. The results demonstrated that EAVG played an effective role, enhancing the flexibility and stability of the bioplastic with potential use in biomedical applications. Moreover, the results also showed significant improvements in mechanical and thermal properties, suggesting that EAVG is a valuable addition to bioplastics. Therefore, EAVG presents a pathway for advancing bioplastics with enhanced mechanical, thermal, and functional characteristics, with the potential for further advancements in these fields.

Monitoring the vegetation structure and species composition of forest restoration (FR) in the Brazilian Amazon is critical to ensuring its long-term benefits. Since remotely piloted aircrafts (RPAs) associated with deep learning (DL) are becoming powerful tools for vegetation monitoring, this study aims to use DL to automatically map individual crowns of Vismia (low resilience recovery indicator), Cecropia (fast recovery indicator), and trees in general (this study refers to individual crowns of all trees regardless of species as All Trees). Since All Trees can be accurately mapped, this study also aims to propose a tree crown heterogeneity index (TCHI), which estimates species diversity based on: the heterogeneity attributes/parameters of the RPA image inside the All Trees results; and the Shannon index measured by traditional fieldwork. Regarding the DL methods, this work evaluated the accuracy of the detection of individual objects, the quality of the delineation outlines and the area distribution. Except for Vismia delineation (IoU = 0.2), DL results presented accurate values in general, as F1 and IoU were always greater than 0.7 and 0.55, respectively, while Cecropia presented the most accurate results: F1 = 0.85 and IoU = 0.77. Since All Trees results were accurate, the TCHI was obtained through regression analysis between the canopy height model (CHM) heterogeneity attributes and the field plot data. Although TCHI presented robust parameters, such as p-value < 0.05, its results are considered preliminary because more data are needed to include different FR situations. Thus, the results of this work show that low-cost RPA has great potential for monitoring FR quality in the Amazon, because Vismia, Cecropia, and All Trees can be automatically mapped. Moreover, the TCHI preliminary results showed high potential in estimating species diversity. Future studies must assess domain adaptation methods for the DL results and different FR situations to improve the TCHI range of action.

Isoprene (Is) emissions by plants represent a loss of carbon and energy resources leading to the initial hypothesis that fast growing pioneer species in secondary tropical forests allocate carbon primarily to growth at the expense of isoprenoid defenses. In this study, we quantified leaf isoprene and methanol emissions from the abundant pantropical pioneer tree species Vismia guianensis and ambient isoprene concentrations above a diverse secondary forest in the central Amazon. As photosynthetically active radiation (PAR) was varied (0 to 3000 µmol m−2 s−1) under standard leaf temperature (30 °C), isoprene emissions from V. guianensis increased without saturation up to 80 nmol m−2 s−1. A nonlinear increase in isoprene emissions with respect to net photosynthesis (Pn) resulted in the fraction of Pn dedicated to isoprene emissions increasing with light intensity (up to 2 % of Pn). Emission responses to temperature under standard light conditions (PAR of 1000 µmol m−2 s−1) resulted in the classic uncoupling of isoprene emissions (Topt, iso > 40 °C) from net photosynthesis (Topt, Pn = 30.0–32.5 °C) with up to 7 % of Pn emitted as isoprene at 40 °C. Under standard environmental conditions of PAR and leaf temperature, young V. guianensis leaves showed high methanol emissions, low Pn, and low isoprene emissions. In contrast, mature leaves showed high Pn, high isoprene emissions, and low methanol emissions, highlighting the differential control of leaf phenology over methanol and isoprene emissions. High daytime ambient isoprene concentrations (11 ppbv) were observed above a secondary Amazon rainforest, suggesting that isoprene emissions are common among neotropical pioneer species. The results are not consistent with the initial hypothesis and support a functional role of methanol during leaf expansion and the establishment of photosynthetic machinery and a protective role of isoprene for photosynthesis during high temperature extremes regularly experienced in secondary rainforest ecosystems.

Habitat loss and fragmentation typically lead to species loss and, consequently, changes in the structure and stability of interaction networks. These changes may lead to important limitation of crucial ecosystems services such as seed dispersal. Here, we compared the spatial structure and species composition of bat-fruit interaction networks in continuous and fragmented forests based on the compilation of 14 datasets from the highly diverse and threatened Atlantic Forest sites in Brazil. As predicted, the number of bat-dispersed species was reduced in fragmented forests. Surprisingly, in both continuous and fragmented forests, bat-fruit networks were nested and modular and presented high complementary specialization. Bat species from genera Artibeus, Carollia, and Sturnira, as well as five plant genera (Cecropia, Ficus, Piper, Solanum, and Vismia) played a central role in both continuous and fragmented forests, revealing small effects of habitat loss on the phylogenetic identity of core species. These bats are considerably tolerant to habitat loss and may support seed dispersal of they preferred plants also in fragmented forests, which explains the similarities of the networks between continuous and fragmented forests. In addition, these key plants provide food resources continuously throughout the year, which facilitates the persistence of seed disperser bats year-round in the community. Although our results indicate that habitat loss had little influence on the structure of the bat-fruit interactions, we evidenced that fragmentation reduces the number of resources consumed and dispersed by bats, which may have negative impacts on forest dynamics and ecosystem functioning.

Plant-based therapies are widely utilized for treating diseases in approximately 80% of the global population, including Colombia’s Chocó Department. This study aimed to identify and evaluate plants with significant therapeutic value for obesity and diabetes in Chocó. The inhibitory effects of these plants on pancreatic lipase (PL), α-glucosidase (AG), and α-amylase (AA) were assessed, and the most promising species were selected to isolate and identify bioactive components. Artocarpus altilis, Momordica balsamina, Bauhinia picta, Neurolaena lobata, and Vismia macrophylla emerged as key species based on their traditional usage among the Chocó population. Notably, the extract derived from Vismia macrophylla demonstrated the most encouraging outcomes as a digestive enzyme inhibitor, exhibiting IC50 values of 0.99 ± 0.21 μg/mL, 5.61 ± 0.82 mg/mL, and 28.91 ± 2.10 μg/mL for AG, AA, and PL, respectively. Further chemical analysis led to the isolation of three bioactive compounds: 5′-demethoxycadensin G 1, para-hydroxybenzoic acid methyl ester 2, and para-hydroxybenzoic acid butyl ester 3. Compound 1 displayed the highest activity against AG (IC50 = 164.30 ± 0.11 μM), while compounds 2 (IC50 = 28.50 ± 4.07 μM) and 3 (IC50 = 10.15 ± 3.42 μM) exhibited potent inhibitory effects on PL. Molecular docking and enzymatic kinetics studies indicate that these bioactive compounds primarily act as mixed inhibitors of AG and non-competitive inhibitors of PL. These findings underscore the potential of V. macrophylla and its compounds as effective inhibitors of digestive enzymes associated with obesity and type 2 diabetes.