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The Miocene is characterized by a series of key climatic events that led to the founding of the late Cenozoic icehouse mode and the dawn of modern biota. The processes that caused these developments, and particularly the role of atmospheric CO₂ as a forcing factor, are poorly understood. Here we present a CO₂ record based on stomatal frequency data from multiple tree species. Our data show striking CO₂ fluctuations of [almost equal to]600-300 parts per million by volume (ppmv). Periods of low CO₂ are contemporaneous with major glaciations, whereas elevated CO₂ of 500 ppmv coincides with the climatic optimum in the Miocene. Our data point to a long-term coupling between atmospheric CO₂ and climate. Major changes in Miocene terrestrial ecosystems, such as the expansion of grasslands and radiations among terrestrial herbivores such as horses, can be linked to these marked fluctuations in CO₂.

Aedes aegypti , the main arbovirus vector of the Yellow fever, Dengue, Chikungunya and Zika viruses, is widely distributed in tropical and subtropical areas throughout the world. Preventive control efforts have been implemented worldwide aimed at reducing its impact on human health. The recent reduction of chemicals available for vector control due to their negative impact on the environment and human health and the increase in mosquito resistance to insecticides have driven the research community to identify and evaluate sustainable alternatives to synthetic insecticides. In this study, the potential larvicidal effect of essential oils extracted from Ocimum campechianum , Ocotea quixos and Piper aduncum were tested in vitro . GC and GC–MS analyses showed that the main compounds were eugenol (18%), 1,8-cineole (39%) and dillapiole (48%), respectively. Susceptibility to essential oils was measured according to the WHO protocol. After 24 h, the mean percentage mortality ranged from 2.7 to 100% for P. aduncum , from 2.2 to 100% for O. campechianum , and from 2.9 to 100% for O. quixos . The highest potential was displayed by P. aduncum , followed by O. campechianum and O. quixos , with LC 50 values of 25.7, 69.3 and 75.5 ppm, respectively. The rapid and effective larvicidal activity of these three oils led us to consider these results to be promising, also considering the possibility of local cultivation of these plants in tropical and subtropical areas and the simple technology for their large-scale preparation and production. Further studies are needed to evaluate the individual components and their activity as larvicides. Aedes aegypti , le principal vecteur d’arbovirus qui provoque la Fièvre Jaune, la Dengue, le Chikungunya et le Zika, est largement répandu dans les régions tropicales et subtropicales du monde entier. Des efforts de contrôle préventif ont été mis en œuvre dans plusieurs pays afin de réduire son impact sur la santé humaine. La récente réduction des produits chimiques disponibles pour la lutte antivectorielle, en raison de leur impact négatif sur l’environnement et la santé humaine, et l’augmentation de la résistance des moustiques aux insecticides, ont amené la communauté des chercheurs à identifier et évaluer des alternatives durables aux insecticides synthétiques. Dans cette étude, l’effet larvicide potentiel des huiles essentielles extraites de Ocimum campechianum , Ocotea quixos et de Piper aduncum a été testé in vitro . Les analyses GC et GC-MS ont montré que les principaux composés étaient respectivement l’eugénol (18 %), le 1,8-cinéole (39 %) et le dillapiole (48 %). La sensibilité aux huiles essentielles a été mesurée conformément au protocole de l’OMS. Après 24 heures, le pourcentage moyen de mortalité variait de 2.7 à 100 % pour P. aduncum , de 2.2 à 100 % pour O. campechianum et de 2.9 à 100 % pour O. quixos . P. aduncum a affiché le potentiel le plus élevé, suivi de O. campechianum et de O. quixos , avec des valeurs CL 50 de respectivement 25.7, 69.3 et 75.5 ppm. L’activité larvicide rapide et efficace de ces trois huiles nous a amenés à considérer les résultats comme prometteurs, compte tenu également de la possibilité de culture locale dans les zones tropicales et subtropicales de ces plantes et de la technologie simple pour leur préparation et leur production à grande échelle. Des études complémentaires sont nécessaires pour évaluer les composants individuels et leur activité en tant que larvicides.

Lauraceae is a family of woody plants of economic importance mainly for their commercial exploitation as timber, as well as spices/food. Nonetheless, overexploitation is causing a decline in both the population and the associated ecosystems due to the lack of sustainability strategies and knowledge of alternative ways of utilization. The focus of this research was to determine if the secondary metabolites found/identified in the volatile fractions/ethyl acetate extracts of Aniba panurensis , Nectandra cuspidata , Ocotea cymbarum and O. myriantha from the Amazon region of Colombia (Departamento de Caquetá) would be promising/interesting for industry, so that uses/exploitation other than timber could be recommended. In this work, the chemical compositions by GC–FID/MS of the volatile fractions/total extracts (by HS–SPME/SDE/maceration) of the trunk wood of these trees were determined. The results were: (i) the volatile fractions/extracts of A. panurensis were composed of 88–94% benzenoid-type aromatic esters (benzyl salicylate and benzoate); (ii) N. cuspidata contained 95% sesquiterpenes (α-copaene and α-cubebene/germacrene D) by HS–SPME, 89% oxygenated and hydrocarbonated sesquiterpenes (τ-cadinol and δ-cadinene) by SDE, and 87% sesquiterpenes and aporphine alkaloids (α-copaene/germacrene D/δ-cadinene/α-cubebene and dicentrine/dehydrodicentrine) by solvent extraction; (iii) O. cymbarum contained mainly 63% sesquiterpenes and monoterpene ethers (α-copaene/ trans -calamenene and eucalyptol) by HS–SPME, 63–85% of monoterpene alcohols (α-terpineol/borneol)/hydrocarbons (α-/β-pinenes)/ethers (eucalyptol) and phenylpropanoid ethers (methyleugenol) by SDE/solvent extraction; and (iv) for O. myriantha , the constituents per family were 91% sesquiterpenes (bicyclogermacrene/germacrene D)—HS–SPME, 72% sesquiterpene alcohols and sesquiterpenes/monoterpenes (spathulenol and bicyclogermacrene/δ-3-carene)—SDE, and 69% benzenoid-type aromatic esters and sesquiterpene hydrocarbons/alcohols (benzyl salicylate and bicyclogermacrene/α-cadinol)—solvent extraction. In conclusion, the main constituents identified in the woods (volatile fractions/extracts) of the species could be isolated and sustainably used/exploitated due to their bioproperties, as well as for their fragrant properties, some of which could be harnessed by different sectors/types of industries.

The genus Ocotea (Lauraceae) includes about 450 species, of which about 90% are Neotropical, while the rest is from Macaronesia, Africa and Madagascar. In this study we present the first complete chloroplast genome sequences of seven Ocotea species, six Neotropical and one from Macaronesia. Genome sizes range from 152,630 ( O. porosa ) to 152,685 bp ( O. aciphylla ). All seven plastomes contain a total of 131 (114 unique) genes, among which 87 (80 unique) encode proteins. The order of genes (if present) is the same in all Lauraceae examined so far. Two hypervariable loci were found in the LSC region ( psbA-trnH , ycf2 ), three in the SSC region ( ycf1 , ndhH , trnL(UAG)-ndhF ). The pairwise cp genomic alignment between the taxa showed that the LSC and SSC regions are more variable compared to the IR regions. The protein coding regions comprise 25,503–25,520 codons in the Ocotea plastomes examined. The most frequent amino acids encoded in the plastomes were leucine, isoleucine, and serine. SSRs were found to be more frequent in the two dioecious Neotropical Ocotea species than in the four bisexual species and the gynodioecious species examined (87 vs. 75–84 SSRs). A preliminary phylogenetic analysis based on 69 complete plastomes of Lauraceae species shows the seven Ocotea species as sister group to Cinnamomum sensu lato. Sequence divergence among the Ocotea species appears to be much lower than among species of the most closely related, likewise species-rich genera Cinnamomum , Lindera and Litsea .

Ocotea species present economic importance and biological activities attributed to their essential oils (EOs) and extracts. For this reason, various strategies have been developed for their conservation. The chemical compositions of the essential oils and matK DNA sequences of O. caudata, O. cujumary, and O. caniculata were subjected to comparison with data from O. floribunda, O. veraguensis, and O. whitei, previously reported. The multivariate analysis of chemical composition classified the EOs into two main clusters. Group I was characterized by the presence of α-pinene (9.8–22.5%) and β-pinene (9.7–21.3%) and it includes O. caudata, O. whitei, and O. floribunda. In group II, the oils of O. cujumary and O. caniculata showed high similarity due amounts of β-caryophyllene (22.2% and 18.9%, respectively). The EO of O. veraguensis, rich in p-cymene (19.8%), showed minor similarity among all samples. The oils displayed promising antimicrobial and cytotoxic activities against Escherichia coli (minimum inhibitory concentration (MIC) < 19.5 µg·mL−1) and MCF-7 cells (median inhibitory concentration (IC50) ≅ 65.0 µg·mL−1), respectively. The analysis of matK gene displayed a good correlation with the main class of chemical compounds present in the EOs. However, the matK gene data did not show correlation with specific compounds.

• Background and Aims Plant growth regulators play an important role in seed germination. However, much of the current knowledge about their function during seed germination was obtained using orthodox seeds as model systems, and there is a paucity of information about the role of plant growth regulators during germination of recalcitrant seeds. In the present work, two endangered woody species with recalcitrant seeds, Araucaria angustifolia (Gymnosperm) and Ocotea odorífera (Angiosperm), native to the Atlantic Rain Forest, Brazil, were used to study the mobilization of polyamines (PAs), indole-acetic acid (IAA) and abscisic acid (ABA) during seed germination. • Methods Data were sampled from embryos of O. odorifera and embryos and megagametophytes of A. angustifolia throughout the germination process. Biochemical analyses were carried out in HPLC. • Key Results During seed germination, an increase in the (Spd + Spm) : Put ratio was recorded in embryos in both species. An increase in IAA and PA levels was also observed during seed germination in both embryos, while ABA levels showed a decrease in O. odorifera and an increase in A. angustifolia embryos throughout the period studied. • Conclusions The (Spd + Spm) : Put ratio could be used as a marker for germination completion. The increase in IAA levels, prior to germination, could be associated with variations in PA content. The ABA mobilization observed in the embryos could represent a greater resistance to this hormone in recalcitrant seeds, in comparison to orthodox seeds, opening a new perspective for studies on the effects of this regulator in recalcitrant seeds. The gymnosperm seed, though without a connective tissue between megagametophyte and embryo, seems to be able to maintain communication between the tissues, based on the likely transport of plant growth regulators.

Sporothrix brasiliensis with low susceptibility isolates were described from the Brazilian zoonotic sporotrichosis hyperendemics. The aim of this work was to evaluate distinct fractions of Ocotea pulchella , Ocotea notata , Myrciaria floribunda , and Hypericum brasiliense plant extracts against itraconazole-sensitive and low susceptibility S. brasiliensis isolates. Crude extracts were tested against clinical isolates and the ATCC MYA4823 to determine the minimum inhibitory concentrations (MICs) and fungicidal or fungistatic activities (MFC). A high MICs and MFCs amplitude (1 – > 128 µg/mL) were obtained for seven extracts. The highest antimicrobial activities against sensitive S. brasiliensis were displayed by the ethyl acetate extracts of O. notata (MIC = 2–128 μg/mL) and M. floribunda (MIC = 1–8 μg/mL). A fungicidal effect was observed for all fraction extracts. Ocotea spp. and M. floribunda ethyl acetate extracts provide promising profiles against itraconazole-sensitive or low susceptibility S. brasiliensis . Future studies will determine if these extracts can contribute as alternative therapies to this neglected zoonosis.

The Atlantic Rainforest in Brazil is currently comprised of small fragments due to the history of conversion and degradation in the last five centuries. The rainforest trees, Ocotea catharinensis, O. odorifera and O. porosa have been heavily harvested because of the high economic value of their timber and essential oils. Their respective habitats have undergone substantial reduction in area due to continuing anthropogenic pressures. As a consequence, these species have suffered large declines in population size and are now considered to be potentially vulnerable to extinction. This study investigated the patterns and levels of genetic diversity and inbreeding of these species using eight microsatellite markers in order to define priority populations for conservation management actions focusing on population enhancement and ex situ germplasm collections. High genetic diversity was found for each of the species with moderate genetic differentiation among populations. Most populations displayed significant inbreeding and isolation by distance. The results provide important information to choose priority populations for both in situ and ex situ conservation measures.

The Ocotea puberula bark powder (OPBP) was evaluated as an effective adsorbent for the removal of crystal violet (CV) from colored effluents. OPBP was characterized and presented a surface with large cavities, organized as a honeycomb. The main functional groups of OPBP were O-H, N-H, C=O, and C-O-C. The adsorption of CV on OPBP was favorable at pH 9 with a dosage of 0.75 g L −1 . The Avrami model was the most suitable to represent the adsorption kinetic profile, being the estimated equilibrium concentration value of 3.37 mg L −1 for an initial concentration of 50 mg L −1 (CV removal of 93.3%). The equilibrium was reached within 90 min. The data were better described by the Langmuir isotherm, reaching a maximum adsorption capacity of 444.34 mg g −1 at 328 K. The Gibbs free energy ranged from − 26.3554 to − 27.8055 kJ mol −1 , and the enthalpy variation was − 11.1519 kJ mol −1 . The external mass transfer was the rate-limiting step, with Biot numbers ranging from 0.0011 to 0.25. Lastly, OPBP application for the treatment of two different simulated effluents was effective, achieving a removal percentage of 90%.

This study compares oil and mucilage idioblasts occurring together in the vegetative organs of Ocotea pulchella, a Lauraceae species. Our focus is specifically on the ontogeny and developmental cytology of these secretory cells. Both types of idioblasts originate from solitary cells located in the fundamental meristem, underlying the protodermis. The growth of both types of idioblasts is asynchronous, with the oil idioblasts developing first, but their initiation is restricted to the early stages of organ development. Mucilaginous idioblasts occur exclusively in the palisade parenchyma, while oil idioblasts are scattered throughout the mesophyll, midrib, and petiole of the leaves. The lamellar secretion of mucilage idioblasts is mostly made up of polysaccharides, while the secretion of oil idioblasts is made up of terpenes and lipids. Cupule occurred only in the oil idioblasts, while suberized layers occurred in both types of cells. We found that immature oil idioblasts that are close to each other fuse; mature mucilage idioblasts have labyrinthine walls arranged in a reticulate pattern; the cells close to the oil idioblasts have a pectin protective layer; and the oil idioblasts have a sheath of phenolic cells. In contrast to previous reports, the two types of secretory idioblasts were recognized during the early stages of their development. The results emphasize the importance of combining optical and electron microscopy methods to observe the ontogenetic, histochemical and ultrastructural changes that occur during the development of the secretory idioblasts. This can help us understand how secreting cells store their secretions and how their walls become specialized.