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The Ocotea complex accommodates most of the taxonomic diversity of Neotropical Lauraceae with economic importance and biological potential attributed to their essential oils (EOs) and extracts. However, the botanical taxonomy has had limitations due to the difficulty of identifying and delimiting species and genera. The chemical and molecular markers of Ocotea complex species in Pará state, Brazil, were assessed according to their EO compositions and DNA sequences of matK, trnL-trnF, and ITS regions. The multivariate analysis of EOs constituents has classified them into two main clusters characterized by oils rich in (I) terpenoids and phenylpropanoids and (II) sesquiterpenes. We conducted a phylogenetic analysis of species based on DNA barcode sequences on the Bayesian Inference (PP: 0.70-1,0) and Maximum Likelihood (BS: 72-100 %). The comparison between the volatile profiles and phylogenetic data indicates two main groups for these species collected from the Ocotea complex.

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Aniba rosiodora has been exploited since the end of the nineteenth century for its essential oil, a valuable ingredient in the perfumery industry. This species occurs mainly in Northern South America, and the morphological similarity among different Aniba species often leads to misidentification, which impacts the consistency of products obtained from these plants. Hence, we compared the profiles of volatile organic compounds (essential oils) and non-volatile organic compounds (methanolic extracts) of two populations of A. rosiodora from the RESEX and FLONA conservation units, which are separated by the Tapajós River in Western Pará State. The phytochemical profile indicated a substantial difference between the two populations: samples from RESEX present α-phellandrene (22.8%) and linalool (39.6%) in their essential oil composition, while samples from FLONA contain mainly linalool (83.7%). The comparison between phytochemical profiles and phylogenetic data indicates a clear difference, implying genetic distinction between these populations.

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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 ß-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 ß-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.

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The aim of the study was to establish a DNA isolation protocol Nectandra megapotamica (Spreng.) Mez., able to obtain samples of high yield and quality for use in genomic analysis. A commercial kit and four classical methods of DNA extraction were tested, including three cetyltrimethylammonium bromide (CTAB)-based and one sodium dodecyl sulfate (SDS)-based methods. Three drying methods for leaves samples were also evaluated including drying at room temperature (RT), in an oven at 40ºC (S40), and in a microwave oven (FMO). The DNA solutions obtained from different types of leaves samples using the five protocols were assessed in terms of cost, execution time, and quality and yield of extracted DNA. The commercial kit did not extract DNA with sufficient quantity or quality for successful PCR reactions. Among the classic methods, only the protocols of Dellaporta and of Khanuja yielded DNA extractions for all three types of foliar samples that resulted in successful PCR reactions and subsequent enzyme restriction assays. Based on the evaluated variables, the most appropriate DNA extraction method for Nectandra megapotamica (Spreng.) Mez. was that of Dellaporta, regardless of the method used to dry the samples. The selected method has a relatively low cost and total execution time. Moreover, the quality and quantity of DNA extracted using this method was sufficient for DNA sequence a...

O objetivo do estudo foi estabelecer um protocolo de isolamento de DNA de Nectandra megapotamica (Spreng.) Mez., capaz de obter amostras de alto rendimento e qualidade para emprego em análises genômicas. Foram testados um kit comercial e quatro métodos clássicos de extração de DNA, incluindo três métodos baseados em brometo de cetiltrimetilamónio (CTAB) e um baseado em dodecil sulfato de sódio (SDS). Três métodos de secagem de amostras de folhas foram também avaliados, incluindo a secagem à temperatura ambiente (RT), em estufa a 40ºC (S40), e em forno microondas (FMO). As soluções de DNA obtidas a partir de diferentes tipos de amostras foliares utilizando os cinco protocolos foram avaliadas em termos de custo, tempo de execução e qualidade e rendimento de DNA extraído. O kit comercial não extraiu DNA com quantidade ou qualidade suficiente para o sucesso das reações de PCR. Entre os métodos clássicos, apenas os protocolos Dellaporta e Khanuja proporcionaram extração de DNA para os três tipos de amostras foliares, que resultaram em reações de PCR e ensaios com enzimas de restrição bem sucedidos. Com base nas variáveis avaliadas, o método de extração de DNA mais apropriado para Nectandra megapotamica (Spreng.) Mez. foi o Dellaporta, independentemente do método utilizado para secar as amostras. O método selecionado apresenta custo e tempo de execução total relativamente baixo. Além...

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The aim of the study was to establish a DNA isolation protocol Nectandra megapotamica (Spreng.) Mez., able to obtain samples of high yield and quality for use in genomic analysis. A commercial kit and four classical methods of DNA extraction were tested, including three cetyltrimethylammonium bromide (CTAB)-based and one sodium dodecyl sulfate (SDS)-based methods. Three drying methods for leaves samples were also evaluated including drying at room temperature (RT), in an oven at 40ºC (S40), and in a microwave oven (FMO). The DNA solutions obtained from different types of leaves samples using the five protocols were assessed in terms of cost, execution time, and quality and yield of extracted DNA. The commercial kit did not extract DNA with sufficient quantity or quality for successful PCR reactions. Among the classic methods, only the protocols of Dellaporta and of Khanuja yielded DNA extractions for all three types of foliar samples that resulted in successful PCR reactions and subsequent enzyme restriction assays. Based on the evaluated variables, the most appropriate DNA extraction method for Nectandra megapotamica (Spreng.) Mez. was that of Dellaporta, regardless of the method used to dry the samples. The selected method has a relatively low cost and total execution time. Moreover, the quality and quantity of DNA extracted using this method was sufficient for DNA sequence a...(AU)

O objetivo do estudo foi estabelecer um protocolo de isolamento de DNA de Nectandra megapotamica (Spreng.) Mez., capaz de obter amostras de alto rendimento e qualidade para emprego em análises genômicas. Foram testados um kit comercial e quatro métodos clássicos de extração de DNA, incluindo três métodos baseados em brometo de cetiltrimetilamónio (CTAB) e um baseado em dodecil sulfato de sódio (SDS). Três métodos de secagem de amostras de folhas foram também avaliados, incluindo a secagem à temperatura ambiente (RT), em estufa a 40ºC (S40), e em forno microondas (FMO). As soluções de DNA obtidas a partir de diferentes tipos de amostras foliares utilizando os cinco protocolos foram avaliadas em termos de custo, tempo de execução e qualidade e rendimento de DNA extraído. O kit comercial não extraiu DNA com quantidade ou qualidade suficiente para o sucesso das reações de PCR. Entre os métodos clássicos, apenas os protocolos Dellaporta e Khanuja proporcionaram extração de DNA para os três tipos de amostras foliares, que resultaram em reações de PCR e ensaios com enzimas de restrição bem sucedidos. Com base nas variáveis avaliadas, o método de extração de DNA mais apropriado para Nectandra megapotamica (Spreng.) Mez. foi o Dellaporta, independentemente do método utilizado para secar as amostras. O método selecionado apresenta custo e tempo de execução total relativamente baixo. Além...(AU)

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Fengshui forests (sacred groves) are important in traditional Chinese culture and home to many endangered species. These forests may provide protection for some endangered plant species outside the nature reserves, but little is known about their role in genetic conservation. Using inter-simple sequence repeat (ISSR) markers, we compared the genetic diversity of 6 populations of Phoebe bournei (Hemsl.) Yang, a commercially important woody species, which is under second-class national protection and endemic to China. Samples were collected from the nature reserves and Fengshui forests in southern China. Herein, we show that Fengshui forest populations are capable of maintaining some level of genetic diversity. For nature reserve populations, the average NA and NE were 1.58 and 1.39, respectively; and for Fengshui forests, they were 1.39 and 1.12, respectively. For nature reserve populations, Nei's gene diversity (H) and Shannon's index (I) were 0.32 and 0.11, respectively; and for Fengshui forests, they were 0.22 and 0.07, respectively. We discuss the reasons for the genetic differences between populations of the Fengshui forests and nature reserves and propose conservation strategies for the Fengshui forest.

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Nectandra megapotamica (Spreng.) Mez. is a tree species that naturally occurs in the Atlantic Forest, Brazil. The aim of this study was to evaluate the genetic diversity and structure of a natural population of 12 N. megapotamica individuals using random amplified polymorphic DNA markers. Eleven primers were used in this study, producing 81 bands, of which 98.99% were polymorphic. Analysis using STRUCTURE defined three different clusters (K = 3), results that were consistent with those of principal coordinates analysis. Both Nei's genetic diversity (h = 0.33) and Shannon's diversity index (I = 0.49) were relatively high. Analysis of molecular variance indicated that 24.89% of the genetic variability was among clusters, while the remaining 75.11% was within clusters. The Mantel test showed a weak correlation between genetic and geographic distances (r = 0.25, P = 0.105). Overall, the results revealed high levels of genetic diversity within clusters and high genetic differentiation among clusters without any spatial pattern of genetic variability. In addition, gene flow was independent of the geographical distribution and was compatible with the hierarchical island model.

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The genetic diversity of 10 Machilus thunbergii populations in eastern China was analyzed using inter-simple sequence repeat markers. The populations showed high genetic diversity, with an overall population genetic diversity of 0.2343. Genetic diversity varied largely among populations, and populations with the highest genetic diversity were mainly from the eastern and western parts of the natural distribution area. Small populations, lack of effective gene flow, and fragmentation of habitats have led to greater genetic differentiation among populations, with 41.18% of genetic variation existing among populations. Unweighted pair-group method with arithmetic mean cluster analysis indicated that populations distributed between latitudes 25° and 31°N were clustered together and should be prioritized for in situ conservation. Northern, eastern, and southern populations were located in peripheral areas of the distribution range and were clustered separately. Collection of distinctive germplasm from peripheral populations should be promoted and ex situ conservation of elite germplasm should be implemented.

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7-epi-sesquithujene (1) is a bicyclic sesquiterpene isolated from phoebe oil, an essential oil of the Brazilian walnut tree, Phoebe porosa. It is also produced by stressed ash trees and has been shown to elicit strong electrophysiological responses on emerald ash borer, Agrilus planipennis, antennae. In the course of the development of a synthetic 7-epi-sesquithujene lure for field testing against the emerald ash borer, we found that the absolute configuration of this compound had not been determined. We isolated >95% pure 7-epi-sesquithujene from phoebe oil via successive fractionation and conventional and argentation (HPLC) chromatographies. The specific optical rotation of this compound matched that of a synthetic product of known configuration. We also synthesized two other stereoisomers of sesquithujene and developed a chiral GC method to separate all four. Based on the specific rotation, stereoselective syntheses, and chiral GC analyses, 7-epi-sesquithujene present in phoebe oil and white ash was found to have the 2S,6S,7R absolute configuration.

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