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Abnormal production of reactive oxygen species (ROS) has been implicated in the physiopathology of neuronal cell death. Increased ROS levels are associated with exacerbated peptide aggregation, inflammation, and mitochondrial dysfunction, which facilitate the triggering of specific cell death pathways. Antioxidant molecules are potentially useful in the amelioration of neurodegeneration. In this regard, natural products are an invaluable source of antioxidants. Therefore, we investigate the antioxidant and neuroprotective activities of four Colombian angiosperm extracts. Antioxidant activity was evaluated by phytochemical assays using TLC techniques with Dragendorff reagent, ninhydrin, and chloranil in dioxane, NH3, Fast Blue, and FeCl3, together with bioautography using DPPH and β-carotene. In vitro neuroprotective activity, cell death, and ROS accumulation were evaluated by MTT and flow cytometry in the SH-SY5Y cell line exposed to paraquat and C2-ceramide. We found that Zanthoxylum rhoifolium Lam, Zanthoxylum martinicense, Nectandra membranacea, and Nectandra reticulata extracts have antioxidant activity higher than quercetin under a β-carotene bleaching assay and protect SH-SY5Y cells against paraquat and C2-ceramide associated with a reduction in ROS. In conclusion, these extracts have a strong neuroprotective potential, and the precise mechanism requires more evaluation. [ABSTRACT FROM AUTHOR]

Considering the complexity and difficulty of identifying forest species, wooden disks were collected to verify the potential of colorimetry to distinguish native species from Araucaria Forest stands of the Lauraceae family. The following species were used: Nectandra megapotamica, Ocotea indecora, Ocotea diospyrifolia and Ocotea puberula. Nees, to provide data on these species that grow naturally in Santa Catarina state, southern Brazil, enriching a robust database that can be practically applied in the commercialization of native woods. Visible spectra and colorimetric parameters were obtained from each anatomical surface and the results were evaluated by comparing the mean of each species regarding radial trunk position and anatomical surface. The data were also submitted to principal component analysis and performance of discriminant models (k-NN, SVM and ANN) for species discrimination with raw and second-derivative data. In general, colorimetric data presented different behavior, and chromatic coordinates a* and b* had higher potential for distinguishing the species. According to the mean spectra, Ocotea indecora had reflectance values different from the other species. By principal component analysis, raw data indicated the separation only of Ocotea indecora, while second-derivative data allowed better distinction of species. In all discrimination models, second-derivative data produced the best results. Thus, the use of colorimetry has potential for wood distinction of the Lauraceae species evaluated, improving the oversight of illegally traded timber.

Considering the complexity and difficulty of identifying forest species, wooden disks were collected to verify the potential of colorimetry to distinguish native species from Araucaria Forest stands of the Lauraceae family. The following species were used: Nectandra megapotamica, Ocotea indecora, Ocotea diospyrifolia and Ocotea puberula. Nees, to provide data on these species that grow naturally in Santa Catarina state, southern Brazil, enriching a robust database that can be practically applied in the commercialization of native woods. Visible spectra and colorimetric parameters were obtained from each anatomical surface and the results were evaluated by comparing the mean of each species regarding radial trunk position and anatomical surface. The data were also submitted to principal component analysis and performance of discriminant models (k-NN, SVM and ANN) for species discrimination with raw and second-derivative data. In general, colorimetric data presented different behavior, and chromatic coordinates a* and b* had higher potential for distinguishing the species. According to the mean spectra, Ocotea indecora had reflectance values different from the other species. By principal component analysis, raw data indicated the separation only of Ocotea indecora, while second-derivative data allowed better distinction of species. In all discrimination models, second-derivative data produced the best results. Thus, the use of colorimetry has potential for wood distinction of the Lauraceae species evaluated, improving the oversight of illegally traded timber. [ABSTRACT FROM AUTHOR]

Societal Impact Statement Trees are essential to life on earth—playing important economic, ecological and cultural roles. However, the world is facing a biodiversity crisis, and to be able to effectively conserve tree species with limited funds, we need to know which tree species are threatened. The Global Tree Assessment has addressed this gap in knowledge through accelerating the production of International Union for Conservation of Nature (IUCN) Red List assessments. Analysing the results of completed taxonomic groups allows for targeted conservation. Here, we explore the extinction risk of six understudied genera with ethnobotanical uses, allowing for conservation priorities to be set. Summary To highlight the ongoing progress of the Global Tree Assessment, a synthesis of the International Union for Conservation of Nature (IUCN) Red List data has been produced for six genera (Gilbertiodendron, Humiriastrum, Liquidambar, Nectandra, Teijsmanniodendron and Tilia) which have all their tree species assessed. This was used to analyse the extinction risk within these groups with the aim of setting conservation priorities and raising awareness of genera not previously publicised in the Global Tree Assessment. The genera were chosen based on completeness, in terms of number of tree species with published IUCN Red List assessments. IUCN Red List categories, threats and uses from each species' IUCN Red List assessment were analysed. An ex situ survey was also carried out to identify species found in botanic gardens, arboreta and seed banks. Higher threat levels were found in the predominately tropical genera (Gilbertiodendron, Humiriastrum, Nectandra and Teijsmanniodendron) compared with the broadly more temperate genera (Tilia and Liquidambar). Habitat loss due to agriculture is a major threat in all genera with exploitation also a key threat to Gilbertiodendron and Tilia. Gilbertiodendron, Humiriastrum, Nectandra and Teijsmanniodendron have no threatened species conserved in ex situ collections. We have identified a need for a range of conservation measures, including collecting threatened species of these groups for ex situ conservation, to ensure no species becomes extinct.

Societal Impact Statement: Trees are essential to life on earth—playing important economic, ecological and cultural roles. However, the world is facing a biodiversity crisis, and to be able to effectively conserve tree species with limited funds, we need to know which tree species are threatened. The Global Tree Assessment has addressed this gap in knowledge through accelerating the production of International Union for Conservation of Nature (IUCN) Red List assessments. Analysing the results of completed taxonomic groups allows for targeted conservation. Here, we explore the extinction risk of six understudied genera with ethnobotanical uses, allowing for conservation priorities to be set. Summary: To highlight the ongoing progress of the Global Tree Assessment, a synthesis of the International Union for Conservation of Nature (IUCN) Red List data has been produced for six genera (Gilbertiodendron, Humiriastrum, Liquidambar, Nectandra, Teijsmanniodendron and Tilia) which have all their tree species assessed. This was used to analyse the extinction risk within these groups with the aim of setting conservation priorities and raising awareness of genera not previously publicised in the Global Tree Assessment.The genera were chosen based on completeness, in terms of number of tree species with published IUCN Red List assessments. IUCN Red List categories, threats and uses from each species' IUCN Red List assessment were analysed. An ex situ survey was also carried out to identify species found in botanic gardens, arboreta and seed banks.Higher threat levels were found in the predominately tropical genera (Gilbertiodendron, Humiriastrum, Nectandra and Teijsmanniodendron) compared with the broadly more temperate genera (Tilia and Liquidambar). Habitat loss due to agriculture is a major threat in all genera with exploitation also a key threat to Gilbertiodendron and Tilia. Gilbertiodendron, Humiriastrum, Nectandra and Teijsmanniodendron have no threatened species conserved in ex situ collections.We have identified a need for a range of conservation measures, including collecting threatened species of these groups for ex situ conservation, to ensure no species becomes extinct. [ABSTRACT FROM AUTHOR]

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The Atlantic Forest in southeastern South America is a biodiversity hotspot with high species richness and high forest loss. Three large to medium-sized woodpecker species (Robust Woodpecker Campephilus robustus, Lineated Woodpecker Dryocopus lineatus, and the globally threatened Helmeted Woodpecker Celeus galeatus) coexist in the south of the ecoregion, and show remarkable convergence in plumage patterns and colouration, possibly driven by interspecific interactions. We assessed differentiation in nest tree species, nest substrates, and timing of breeding and evaluated whether nesting ecology may be a factor explaining an association with mature forests in the Helmeted Woodpecker. Robust and Lineated Woodpeckers excavated cavities in nine and eight nest tree species, respectively, whereas Helmeted Woodpeckers specialized narrowly on laurel trees (88% of nest cavities in two species in genus Nectandra of 52 ± 14 cm DBH). Helmeted Woodpecker is further distinguished by a more frequent use of living, partially decayed trees and by more frequent re-use of nest cavities. When nesting in selectively logged forest (vs. old-growth), Robust and Lineated Woodpeckers used trees with smaller DBH and Robust Woodpeckers excavated lower in trees. Helmeted Woodpeckers selected nest trees with similar dimensions in both environments, indicating lesser flexibility. Helmeted Woodpeckers bred 20–23 days later in the year than Lineated and Robust Woodpeckers, potentially allowing them to avoid nesting near the two larger species. The narrow specialization of Helmeted Woodpecker on nesting in Nectandra trees of large sizes at the onset of decay is a possible factor in making it sensitive to selective logging effects. To stop declines of Helmeted Woodpecker we recommend (1) sparing large trees from selective logging (including Nectandra and tree species used for roosting), and (2) restoring more forested areas to mature forest conditions. [ABSTRACT FROM AUTHOR]

Abstract In this work was evaluated the cytotoxic activity of dehydrodieugenol B (1) and methyldehydrodieugenol B (2) isolated from Nectandra leucantha (Lauraceae) through cytokinesis-block micronucleus (CBMN) and Comet assay. Compounds 1 and 2 displayed in vitro toxicity against human melanoma cells (SKMEL-147) with IC 50 values of 4.4 and 43.6 μg/mL, respectively. The interaction of these compounds with resistant human melanoma cell line SKMEL-29 was also investigated. Obtained results showed a concentration-response relationship for DNA damage (DI and D%) in SKMEL-29 cells for compounds 1 and 2 causing an increase in DNA damage on their lower concentrations. Concerning the cytokinesis-block micronucleus cytome (CBMNCyt) assay, all treatments demonstrated an increase in cytostatic and cytotoxic indexes. In micronucleus quantification, compound 1 displayed higher index in comparison to control. Regarding necrotic and apoptotic cells, treatments with SKMEL-29 cells demonstrated 100% of cell death induced by compounds 1 and 2 at 25 and 88 μg/mL, respectively. Additionally, it was observed that apoptosis is prevalent in SKMEL-147 cells treated with compound 1 , while necrotic cells were observed in SKMEL-29 cells treated with both compounds. In conclusion, compounds 1 and 2 are suggested as promising cytotoxic agents against human melanoma resistant cells, emphasizing the potential use of these neolignans for the treatment of melanoma. Highlights • Neolignans 1–2 were isolated from twigs of Nectandra leucantha (Lauraceae) • Neolignans 1–2 displayed toxicity against human melanoma cells SKMEL-147. • Neolignans 1–2 are suggested as promising genotoxic and cytotoxic agents against human melanoma resistant cells. [ABSTRACT FROM AUTHOR]

In this study, we aimed to determine whether seasonality affects the content, chemical composition, and antimicrobial activity of essential oils (EOs) from the leaves of three species of Nectandra (Nectandra megapotamica, Nectandra grandiflora, and Nectandra lanceolata) native to the Atlantic rainforest, Sao Paulo state, Brazil. In addition, we identified the compounds potentially related to the antimicrobial activity. Leaves were randomly collected in the middle of winter (August), spring (November), summer (February), and autumn (May). The influence of seasonality on the content and chemical composition of EOs from the Nectandra species was evident in this study. The EOs from N. lanceolata and N. grandiflora were characterized by similarities in the chemical composition and had a higher relative proportion of oxygenated sesquiterpenes. N. megapotamica presented a different chemical profile, with plenty of monoterpenic and sesquiterpenic hydrocarbons. Changes in the EO chemical profile because of seasonality were shown by the similarities between the EOs obtained in spring and autumn and the differences between the EOs obtained in summer and winter. The EO from the leaves of N. megapotamica harvested in winter and spring showed the highest control of the growth of Escherichia coli, and this antimicrobial action can be related to the monoterpenes α-pinene and β-pinene as well as myrcene and limonene. The minimum inhibitory concentration (MIC) of the EO from the leaves of N. lanceolata harvested in summer and autumn was lower against the gram-positive bacterium Staphylococcus aureus and can be related to the sesquiterpene hydrocarbons isobicyclogermacrenal, epi-zizanone, and germacrene B. [ABSTRACT FROM AUTHOR]

Plants produce a wide range of secondary metabolites. Within a single species, chemotypes can be distinguished by the differences in the composition of the secondary metabolites. Herein, we evaluated Nectandra megapotamica (Spreng.) chemotypes and the balance of different classes of metabolites to verify how significant differences in plant metabolism are regarding chemotypes. We collected N. megapotamica leaves from eight adult plants in two Brazilian states. The essential oils and ethanol/water extracts were analyzed by GC-MS and LC-DAD-MS, respectively. Histochemical tests were performed, as well as chemical analyses of leaves from adaxial and abaxial foliar surfaces of N. megapotamica, and the stereochemistry of α-bisabolol was determined. Two different chemotypes, based on volatile compounds, were identified, distinguished by the presence of isospathulenol, α-bisabolol, β-bisabolene, and (E)-nerolidol for chemotype A, and bicyclogermacrene and elemicin for chemotype B. A stereochemical analysis of chemotype A extract revealed (+)-α-bisabolol enantiomer. Histochemical tests of chemotypes showed similar results and suggested the presence of essential oil in idioblasts stained with the dye NADI. The analyses of chemotype A leaves by GC-MS revealed similar compositions for abaxial and adaxial surfaces, such pattern was also observed for chemotype B. Medium and high polarity metabolites showed high chemical similarities between the chemotypes, highlighting the presence of proanthocyanidins and glycosylated flavonoids (O- and C-glycosides). Thus, N. megapotamica produced distinct volatile chemotypes with highly conserved medium to high polarity compounds. Such results suggest that phenolic derivatives have a basal physiological function, while genetic or environmental differences lead to differentiation in volatile profiles of N. megapotamica. [ABSTRACT FROM AUTHOR]

The total phenolic content (TP) and antioxidant activity of the ethanolic extract and fractions that were obtained from the leaves of Nectandra hihua were assessed using different methods. The ethanolic extract (EE) and ethyl acetate fraction (EAF) had the best antioxidant capacity, which was comparable to butylated hydroxytoluene and quercetin (ABTS + 2.55 ± 0.06, 3.54 ± 0.03 mmol TE/g; DPPH IC 50 10.27 ± 0.05, 9.88 ± 0.02 μg/mL; FRAP 2.17 ± 0.08, 2.38 ± 0.04 mmol TE/g; ORAC 5.16 ± 0.08, 5.35 ± 0.07 mmol TE/g; TP 568.05 ± 18.15, 397.20 ± 17.88 mg GAE/g, respectively). The cytoprotective effect, reactive oxygen species (ROS) and lipid peroxidation inhibitions on L929 fibroblasts irradiated with UVB (600 mJ/cm 2 ) in pre- and post-treatments with EE and EAF were determined. These plant materials demonstrated high ROS scavenging activity and lipid peroxidation inhibition on L929 fibroblasts in both treatments, especially with pre-treatment (EE 38.47 ± 1.95% and EAF 40.20 ± 4.5% inhibition of ROS production, and EE 39.03 ± 3.33% and EAF 41.67 ± 7.6% of lipid peroxidation inhibition), indicating the best cytoprotection with pre-treatment (13.52 ± 1.66% and 13.34 ± 2.61% increases in cell viability). The antioxidant flavonoids quercitrin, avicularin, juglalin, afzelin and astragalin were isolated from EAF. The results obtained indicate that EE and EAF present photodamage attenuating potential against UVB-induced oxidative stress and can be useful as a starting point for developing dermatological products to prevent oxidative skin damage. [ABSTRACT FROM AUTHOR]

Nectandra grandiflora Nees (Lauraceae) is a Brazilian native tree recognized by its durable wood and the antioxidant compounds of its leaves. Taking into account that the forest industry offers the opportunity to recover active compounds from its residues and by-products, this study identifies and underlines the potential of natural products from Nectandra grandiflora that can add value to the forest exploitation. This study shows the effect of three different extraction methods: conventional (CE), ultrasound-assisted (UAE) and microwave-assisted (MAE) on Nectandra grandiflora leaf extracts (NGLE) chemical yields, phenolic and flavonoid composition, physical characteristics as well as antioxidant and antifungal properties. Results indicate that CE achieves the highest extraction phytochemical yield (22.16%), but with similar chemical composition to that obtained by UAE and MAE. Moreover, CE also provided a superior thermal stability of NGLE. The phenolic composition of NGLE was confirmed firstly, by colorimetric assays and infrared spectra and then by chromatographic analysis, in which quercetin-3-O-rhamnoside was detected as the major compound (57.75–65.14%). Furthermore, the antioxidant capacity of the NGLE was not altered by the extraction methods, finding a high radical inhibition in all NGLE (>80% at 2 mg/mL). Regarding the antifungal activity, there was observed that NGLE possess effective bioactive compounds, which inhibit the Aspergillus niger growth. [ABSTRACT FROM AUTHOR]

Context:New antileishmanias are needed because of toxicity, high cost and resistance problems associated with available drugs.Nectandra(Lauraceae) produces several classes of compounds but its essential oil has not previously been reported to have antileishmania activity. Objective:We evaluated the cytotoxicity and antileishmania activity of essential oils fromNectandra amazonumNees,N. gardneriMeisn.,N. hihua(Ruiz & Pav.) Rohwer andN. megapotamica(Spreng.) Mez. Materials and methods:Nectandraoils were extracted from stem bark/leaves by hydrodistillation and compounds were identified by GC-MS. Oils were tested againstLeishmania infantumandL. amazonensisintracellular amastigotes and nitric oxide production was evaluated. Cytotoxicity was achieved on NIH/3T3 and J774.A1 cells for the selectivity index (SI). Results and discussion:Nectandra gardneriwas active againstL. infantumandL. amazonensis(IC50 =  2.7 ± 1.3/2.1 ± 1.06 μg/mL) and contained 85.4% sesquiterpenes, of which 58.2% was intermediol. Besides low cytotoxicity (SI >11.3),N. gardneriinduced a significant increase in NO production byL. infantum-infected macrophages.Nectandra hihuahad the best activity onL. infantumamastigotes (IC50 =  0.2 ± 1.1 μg/mL). This oil was 89.0% sesquiterpenes, with 28.1% bicyclogermacrene. The two specimens ofN. megapotamicahad different activities on amastigotes. The one richer in sesquiterpenes (49.9%) was active against both species (IC50 =  12.5 ± 1.4/21.3 ± 1.2) and had phenylpropanoidE-asarone as the main compound (42.4%).Nectandra amazonumshowed moderate activity on both the species (IC50 =  31.9 ± 2.0/22.1 ± 1.3 μg/mL) and low selectivity (0.9 < SI >2.6), probably due to the major presence of β-caryophyllene (28.5%). Conclusions:Our data identify compounds that can now be isolated and used for the development of new antileishmanias. [ABSTRACT FROM PUBLISHER]

Chagas disease is a neglected tropical disease, caused by the protozoan parasite Trypanosoma cruzi , which affects more than eight million people in Tropical and Subtropical countries especially in Latin America. Current treatment is limited to nifurtimox and benznidazole, both with reduced effectiveness and high toxicity. In this work, the n -hexane extract from leaves of Nectandra leucantha (Lauraceae) displayed in vitro antitrypanosomal activity against T. cruzi . Using several chromatographic steps, four related neolignans were isolated and chemically characterized as dehydrodieugenol B ( 1 ), 1-(8-propenyl)-3-[3′-methoxy-1′-(8-propenyl)-phenoxy]-4,5-dimethoxybenzene ( 2 ), 1-[(7S)-hydroxy-8-propenyl]-3-[3′-methoxy-1′-(8′-propenyl)-phenoxy]-4-hydroxy-5-methoxybenzene ( 3 ), and 1-[(7S)-hydroxy-8-propenyl]-3-[3′-methoxy-1′-(8′-propenyl)-phenoxy]-4,5-dimethoxybenzene ( 4 ). These compounds were tested against intracellular amastigotes and extracellular trypomastigotes of T. cruzi and for mammalian cytotoxicity. Neolignan 4 showed the higher selectivity index (SI) against trypomastigotes (>5) and amastigotes (>13) of T. cruzi. The investigation of the mechanism of action demonstrated that neolignan 4 caused substantial alteration of the plasma membrane permeability, together with mitochondrial dysfunctions in trypomastigote forms. In silico studies of pharmacokinetics and toxicity (ADMET) properties predicted that all compounds were non-mutagenic, non-carcinogenic, non-genotoxic, weak hERG blockers, with acceptable volume of distribution (1.66–3.32 L/kg), and low rodent oral toxicity (LD 50 810–2200 mg/kg). Considering some clinical events of cerebral Chagas disease, the compounds also demonstrated favorable properties, such as blood-brain barrier penetration. Unfavorable properties were also predicted as high promiscuity for P450 isoforms, high plasma protein binding affinity (>91%), and moderate-to-low oral bioavailability. Finally, none of the isolated neolignans was predicted as interference compounds (PAINS). Considering the promising chemical and biological properties of the isolated neolignans, these compounds could be used as starting points to develop new lead compounds for Chagas disease. [ABSTRACT FROM AUTHOR]

Chemosentizing of pathogens using natural compounds has been shown to be a promising alternative, resulting in increased efficacy of classical antifungal therapy. This study determines the chemical composition and antifungal, antichemotactic and antioxidant activities of Nectandra Rol species. ex Rottb. essential oils species, and its interaction with commercial antifungals. The chemical composition of N. megapotamica and N. lanceolata essential oils was established by gas chromatography–mass spectrometry (GC–MS). The major compounds identified in N. megapotamica oil were bicyclogermacrene (33.4%) and germacrene D (16.8%), while N. lanceolata were identified β-caryophyllene (32.5%), bicyclogermacrene (27.8%) and spathulenol (11.8%). The oils presented antidermatophytic effect and affinity by ergosterol indicating a possible involvement in fungal membrane. The combination of the essential oil from N. lanceolata and ciclopirox showed synergistic and additive effect on most isolates (75%) reducing the active concentration of the antifungal agents when in combination. The oils were also tested for their ability to inhibit leukocyte migration in vitro stimulated by Escherichia coli lipopolysaccharide and showed antichemotactic effect with reduction in migration in the range of 30.7–96.7%, suggesting that it could act in acute stage of inflammatory process. Antioxidant concentration-dependent activity was observed on both samples. N. lanceolata showed 50% antioxidant effect in the highest concentration tested. The results of the combination between antifungals and N. lanceolata essential oil indicate this oil as a possible complement to conventional therapy for topical treatment of superficial infections caused by dermatophytes, acting in the chemosensitization of the fungal cell and resulting in antifungal effect improvement with the advantage of the anti-inflammatory effect associated. [ABSTRACT FROM AUTHOR]

Introduction: Leishmaniasis is a parasitic neglected disease affecting millions of people worldwide. Clinical practice resorts to long and costly treatments with a therapeutic arsenal limited to highly toxic drugs, often associated to adverse side effects. Additionally, resistant strains are reported to be increasing. Aim: In this work, the mechanistic action of a drug candidate (methydehydrodieugenol B), isolated from twigs of Nectandra leucantha, towards Leishmania infantum was studied by a global metabolomics approach using GC-MS and RPLC-MS platforms. Method: L. infantum promastigotes were grown in culture medium for 72 h and treated with methydehydrodieugenol B at 58.18 μg.mL-1 concentration; after 48 h treatment, enzyme activity was quenched, cells washed and frozen until analysis. For GC-MS analysis (Fiehn's method), 1:1 methanol:water extracts were prepared and derivatized with O-methoxyamine in pyridine at room temperature for 90 min, followed by silylation with BSTFA/1% TMCS at 40 °C for 30 min. Pure methanolic extracts were also prepared and analyzed directly by RPLC-MS with a acetonitrile/water mobile phase acidulated with formic acid and gradient elution. Result: Several amino acids, fatty acids, carbohydrates, and glycerolipids were found as discriminant metabolites, mostly decreased in treated samples. Due to the complexity of the parasite metabolism and the great diversity of altered metabolites, a multi-target mechanism was assigned to the drug candidate, where changes in the cell energy sources and in the lipid composition of the parasite plasma membrane were prominent. Conclusion: These results contributed to elucidate the broad action of methyldehydrodieugenol B against Leishmania, paving the way in the search of novel alternative therapies. [ABSTRACT FROM AUTHOR]

Nectandra Rol. ex Rottb. apresenta 14 espécies no Paraná: Nectandra angustifolia (Schrader) Nees & Mart., N. cissiflora Nees, N. cuspidata Nees & Mart., N. grandiflora Nees & Mart., N. hihua (Ruiz & Pav.) Rohwer, N. lanceolata Nees & Mart., N. leucantha Nees & Mart., N. megapotamica (Sprengel) Mez, N. membranacea (Sw.) Griseb., N. nitidula Nees & Mart., N. oppositifolia Nees & Mart., N. paranaensis Coe-Teixeira, N. puberula (Schott) Nees e N. reticulata (Ruiz & Pav.) Mez. São apresentados chave para identificação e descrições de cada espécie, assim como ilustrações e dados sobre sua fenologia e distribuição. Nectandra hihua é citada pela primeira vez para o Estado.Nectandra Rol. ex Rottb. has 14 species in Paraná: Nectandra angustifolia (Schrader) Nees & Mart., N. cissiflora Nees, N. cuspidata Nees & Mart., N. grandiflora Nees & Mart., N. hihua (Ruiz & Pav.) Rohwer, N. lanceolata Nees & Mart., N. leucantha Nees & Mart., N. megapotamica (Sprengel) Mez, N. membranacea (Sw.) Griseb., N. nitidula Nees & Mart., N. oppositifolia Nees & Mart., N. paranaensis Coe-Teixeira, N. puberula (Schott) Nees and N. reticulata (Ruiz & Pav.) Mez. We present an identification key and species descriptions, as well as illustrations and data on phenology and geographic distribution. N. hihua is cited for the first time in Paraná State.

Earlier studies indicated that the genus Nectandra, currently the second-largest genus of the Neotropical Lauraceae, might be diphyletic in its traditional circumscription, but the evidence was not quite conclusive. Our phylogenetic analyses based on nuclear (ITS) and chloroplast (psbA-trnH) sequences of 45 Nectandra species as well as 42 representatives of 18 genera of the core Lauraceae (Ocotea complex, Laureae, Aiouea, Asian Cinnamomum and Persea groups) confirm the suspicion that Nectandra is diphyletic. The two groups, Nectandra s.str. and the N. coriacea group, are each well supported in the maximum parsimony and Bayesian analyses, but they are not sister to each other. Nectandra s.str. is sister to Pleurothyrium, and the clade including Nectandra s.str. and Pleurothyrium is very likely closer to the dioecious taxa of the Ocotea complex. The N. coriacea group, on the other hand, appears to be closer to bisexual taxa known as the Ocotea helicterifolia group. In addition, Nectandra s.str. is characterized by a large deletion in the psbA-trnH spacer compared to all other core Lauraceae, including its sister group Pleurothyrium. Considering these facts, Nectandra cannot be maintained in the traditional sense. We therefore transfer the species of the N. coriacea group to the oldest generic name applied to this group, Damburneya. On the basis of fossil records from the American subcontinents and in accordance with previous phylogenetic and molecular clock studies we suggest a scenario of a climate-driven migration from North to South America, with a subsequent rapid radiation of Nectandra s.str. in South America. [ABSTRACT FROM AUTHOR]

The environmental toxicity and potential human health problems that can be caused by most common wood preservatives are pushing forward the search of safe preservatives from renewable resources. Consequently, several studies have been realized to assess the potential of plant extracts in terms of fungal resistance for wood products. In this context, the present work aims to evaluate the inhibitory effects of essential oil obtained from the leaves of Nectandra grandiflora against wood decay fungi. Chemical characterization was carried out by gas chromatography and the antifungal activity was performed by the radial growth technique. Firstly, the potato sucrose agar medium was supplemented with essential oil at concentrations ranging from 0 (control) to 5.0 µL⋅mL-1. Afterwards, mycelial discs of Pycnoporus sanguineus and Gloeophyllum trabeum were transferred to the plates and the results were evaluated by the probit method. Chemical analysis revealed a complex mixture of sesquiterpenoids in the essential oil, which presented dehydrofukinone as a major compound. The essential oil and dehydrofukinone proved to be effective in the mycelial growth control of G. trabeum and P. sanguineus. These preliminary reports demonstrated the suitability of the N. grandiflora essential oil as a component of preservative solutions. [ABSTRACT FROM AUTHOR]

The Lauraceae, a characteristic family of Peru’s eastern montane forests are represented in Peru by 16 genera and 247 species (Brako & Zarucchi, 1993; Ulloa Ulloa et al., 2004). Here we recognize 55 endemic species included in 11 genera. Nectandra and Ocotea are the genera with the largest number of endemic species. These endemic taxa, mostly trees and shrubs, are found mainly in the Humid Lowland Amazonian Forest and Very Humid Montane Forest regions, between 125 and 3100 m elevation. Nine of these species have been recorded to date in the Peruvian protected areas system.

Context: Nectandra (Lauraceae) species have been used in folk medicine as an antidiarrheal, analgesic, antifungal, etc., and have many pharmacological proprieties. Objective: Investigation of the chemical composition and cytotoxicity of essential oil from Nectandra leucantha Nees & Mart. leaves. This is the first study involving N. leucantha reported in the literature. Material and methods: The essential oil of N. leucantha leaves was obtained by hydrodistillation. Its chemical composition was determined using a combination of GC/FID, GC/MS, and determination of Kovats index (KI). In vitro cytotoxic activity was evaluated against six cancer cell lines - murine melanoma (B16F10-Nex2), human glioblastome (U-87), human cervical carcinoma (HeLa), human colon carcinoma (HCT), human breast adenocarcinoma (MCF7), and human cervical tumor (Siha) as well as against one non-tumorigenic cell line - human foreskin fibroblast (HFF). Results: Thirty-three compounds were identified primarily sesquiterpenes (81.41%), the main compounds being bicyclogermacrene (28.44%), germacrene A (7.34%), spathulenol (5.82%), and globulol (5.25%). Furthermore, monoterpenes were also found in the analyzed oil (12.84%), predominantly α- and β-pinenes (6.59 and 4.57%, respectively). The crude essential oil displayed significant cytotoxic activity against B16F10-Nex2 (IC50 33 ± 1 μg/mL) and U87 (IC50 75.95 ± 0.03 μg/mL) and HeLa (IC50 60 ± 12 μg/mL) cell lines. The main identified compound, bicyclogermacrene, displayed IC50 ranging from 3.1 ± 0.2 to 21 ± 6 μg/mL. Discussion and conclusion: The results indicate that the crude oils from leaves of N. leucantha displayed cytotoxic activity being bicyclogermacrene, the main compound identified in the crude oil responsible, at least in part, for this potential. [ABSTRACT FROM AUTHOR]

The essential oil from leaves of Nectandra antillana Meisn. grown in Cuba was isolated by hydrodistillation and analyzed by gas chromatography/flame ionization detector (GC/FID) and GC/mass spectrometry (GC/MS). One hundred and fifty compounds were identified and quantified, accounting for 99% of the total composition. The essential oil was rich in sesquiterpene compounds, particularly caryophyllene oxide (16.0%), β-caryophyllene (9.9%) and guaiol (8.7%). The in vitro antibacterial activity of the essential oil was studied against five bacteria strains (Bacillus cereus, Bacillus subtilis, Escherichia coli, Staphylococcus aureus and Listeria monocytogenes) using the disc diffusion method. The essential oil was slightly effective against nearly all bacteria tested, except for B. subtilis. [ABSTRACT FROM AUTHOR]

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Antisnake activity of extracts and essential oil of Nectandra megapotamica was tested in vitro against the Bothrops diporus venom (yarará chica). Inhibitory activity of the hemolytic action on the aqueous extract and essential oil; inhibition of the procoagulant action on hexanic extract and condensed water from steam distillation; and inhibition of the proteolytic activity on alcoholic extract and condensed water was found. In all cases, the main antisnake venom activity was found on plant material collected in the autumn. The chemical composition of the N. megapotamica essential oil was characterized during different vegetative states finding a clear predominance of mono- (21.0–31.7) and sesquiterpene (58.5–68.9) hydrocarbons. The differences found with previous results published for this species, growing in other geographic places, opens the option for the existence of chemical types. [ABSTRACT FROM AUTHOR]

Various nondestructive techniques have been developed to evaluate wood quality. However, these studies were conducted mainly for temperate species. The Central Amazonian forests have more than 300 tree species per ha (> 10 cm diameter at breast height) and few studies using nondestructive techniques were conducted on these species. This study aimed to test a nondestructive technique, with application of stress waves, for the evaluation of hardness of timber species in the Central Amazon. The study was conducted in Itacoatiara city, Brazil (43° 2'-3° 04' S and 58° 31'-58° 57' W). Three timber species, namely, Nectandra cuspidata, Mezilaurus itauba and Ocotea guianensis were evaluated for hardness using nondestructive and destructive methods. Models adjusted for valuation of properties based on the speed of propagation of stress waves (r² = 0.54-0.59) and wood density (r² = 0.73-0.78) allowed the prediction of hardness of the wood species. Thus, the tested nondestructive techniques showed sufficient performances to predict timber hardness and would improve efficiency of the process to evaluate timber quality. [ABSTRACT FROM AUTHOR]

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Abstract: We used maximum quantum yield of photosystem II (PSII) to study the functional state of Amazonian floodplain tree species after prolonged submergence. Saplings of four common tree evergreen species which maintain their leaves when submerged were analysed. The responses showed that (1) maximum quantum yield of PSII in all submerged mature leaves remained in the range of healthy non-flooded leaves with maximum quantum yield of photosystem II F v/F m never dropping below 0.66 in the four species, indicating an intact photosynthetic apparatus. (2) In young mature leaves (2–7 mo) F v/F m is higher, ranging from 0.76 to 0.82, than in old mature leaves aged >10 mo where F v/F m ranges from 0.73 to 0.78. (3) F v/F m values of saplings are significantly lower (0.3–0.6) shortly after being taken out of darkness and out of the water than before submersion (0.66–0.78). Leaves suffered from photoinhibition when taken out of the darkness from below water, with decreases of 70% in F v/F m, but they recovered full photosynthetic activity within approximately one week after the end of submersion indicating that all leaves retained the potential to be photosynthetically active in spite of six months of submersion in darkness. A recovery period of F v/F m of over several days, as described for Pouteria glomerata, Tabernaemontana juruana, Gustavia augusta and Nectandra amazonum after long-lasting submergence, has not been reported so far. [Copyright &y& Elsevier]

The dynamics of leaf breakdown in a headwater Colombian stream were evaluated for the native tree species Myrsine guianensis, Cupania latifolia and Nectandra lineatifolia using coarse and fine mesh litter bags. Ten bags of each species (five of each mesh size) were retrieved from the stream at 1, 8, 15, 30, 60 and 120 days. k values ranged from 0.0008 to 0.0058 day–1 and density of macroinvertebrates from 35 to 55 individuals per leaf bag, peaking at day 8. Myrsine guianensis degraded more rapidly than the other species for both coarse and fine mesh bags. This species and Nectandra lineatifolia presented differences in k values between coarse and fine mesh bags, suggesting that macroinvertebrates influenced the decay rate. Despite the low densities of macroinvertebrates found, shredders represented 12.7% of individuals and 50 to 68% of the invertebrate biomass in bags, indicating that this functional feeding group was an important component of fauna associated with litter breakdown in this first order tropical stream. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Trees of the Amazon River floodplain (várzea) are subjected to regular periods of waterlogging which last up to seven months every year. The present study shows the importance of stem water storage for buffering root water uptake restrictions during water logging in different tree species which are common in this environment. With the method of Granier, total water fluxes were measured in five individuals of each of six species (Crateva benthami, Laetia colymbulosa, Nectandra amazonum, Pseudobombax munguba, Tabebuia barbata and Vitex cymosa ) with different phenologies, located in a várzea inundation forest near Manaus, Brazil. Xylem sap flux density was positively correlated with the above stand or upper canopy diurnal variation of vapour pressure deficit in all tree species under study. Increasing above stand or upper canopy vapor pressure deficit lead to an increasing sap flux density and total sap flow, and vice versa. Reduced water availability during day time was buffered by stem water which was filled up during night time. The severe physiological stress caused by anoxic conditions in the root zone was indicated by a reduction of the transpiring surfaces via leaf shedding. Stem water store could buffer water shortage during day time. [ABSTRACT FROM AUTHOR]

Bioactivity-guided fractionation of a MeOH–EtOAc extract from the young leaves of Nectandra lineata (Lauraceae), using a Trypanosoma cruzi bioassay resulted in the isolation of a novel norlignan 3'-methoxy-3,4-methylenedioxy-4',7-epoxy-9-nor-8,5'-neolignan-9'-acetoxy ( 1 ), together with the known compound, 3'-methoxy-3,4-methylenedioxy-4'-7-epoxy-9-nor-8,5'-neolignan-7,8'-diene ( 2 ). Compounds 1 and 2 were shown to inhibit the growth of T. cruzi epimastigotes in axenic culture. [ABSTRACT FROM AUTHOR]

The phytochemical study of Nectandra cuspidata led to the isolation and characterization of the new megastigmane 7-megastigmen-3β,6β,9ξ-triol ( 1 ), the aporphinoid alkaloids (−)-glaziovine ( 2 ) and (+)-apoglaziovine ( 3 ), the sesquiterpene costic acid ( 4 ), polyprenols ( 5 , 6 and 8 ), α-tocopherol ( 7 ) and the steroid β-sitosterol ( 9 ). The structures of the compounds were elucidated based on spectroscopic data. This is the first description of the presence of megastigmanes in Nectandra genus. All compounds ( 1-9 ) were isolated for the first time from this species. The chemotaxonomic significance of these compounds was also summarized. [ABSTRACT FROM AUTHOR]