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Footnote : Numbers in PCA biplot correspond to 2- O -Caffeoyltartaric acid (5), 3- O -caffeoylquinic acid (6), 5- O -caffeoylquinic acid (8), caffeic acid (9), 4- O -caffeoylquinic acid (10), 5- O -caffeoylshikimic acid (13), 1,3- O -dicaffeoylquinic acid (15), 5- O -feruloylquinic acid (17), 2,3- O -dicaffeoyltartaric acid (18), quercetin 3- O -rutinoside (19), quercetin 3- O -glucoside (20), 3,4- O -dicaffeoylquinic acid (21), kaempferol 3- O -rutinoside (22), 3,5- O -dicaffeoylquinic acid (23), quercetin 3- O -rhamnoside (24), caffeoylferuloyltartaric acid (25), 4,5- O -dicaffeoylquinic acid (26) and kaempferol 3- O -rhamnoside (31). Distribution map of the here analyzed samples of Dasyphyllum and Archidasyphyllum. • First metabolomic characterization of the genera Dasyphyllum and Archidasyphyllum. • Chemophenetics supports the recent new circumscription of Dasyphyllum and Archidasyphyllum. • Quinic and shikimic acid esters are the main constituents of Dasyphyllum. • Tartaric acid esters are diagnostic compounds for Archidasyphyllum. Dasyphyllum Kunth is the most diverse genus of the South American subfamily Barnadesioideae (Asteraceae), comprising 31 species most of which are distributed along the Brazilian Atlantic Forest, Cerrado and Caatinga domains. The genus has traditionally been divided into two subgenera, namely Archidasyphyllum and Dasyphyllum. However, recent phylogenetic, morphological, and biogeographical evidence led to a new circumscription of Dasyphyllum by elevating the subgenus Archidasyphyllum to the generic rank. The present work aimed to explore a chemophenetic characterization of Dasyphyllum for further supporting its new circumscription by a metabolomic approach using liquid chromatography coupled to high resolution mass spectrometry and multivariate statistical analyses. A total of 44 mass features were identified based on their UV spectra, high resolution MS data and MS2 fragmentation patterns as well as comparisons with standard compounds. Dasyphyllum samples exhibited a diversity of phenylpropanoids: 3- O -caffeoylquinic acid, 4- O -caffeoylquinic acid, 5- O -caffeoylquinic acid, 5- O -feruloylquinic acid, 5- O -caffeoylshikimic acid, 1,3- O -dicaffeoylquinic acid, 3,4- O -dicaffeoylquinic acid, 3,5- O -dicaffeoylquinic acid and 4,5- O -dicaffeoylquinic acid. On the other hand, Archidasyphyllum displayed the 2- O -caffeoyltartaric acid, 2,3- O -dicaffeoyltartaric acid and caffeoyl-feruloyltartaric acid as distinctive constituents. The occurrence of tartaric acid ester derivatives in Archidasyphyllum and its absence in Dasyphyllum may constitute a diagnostic chemical characteristic for further supporting the segregation of Archidasyphyllum from Dasyphyllum. The occurrence of phenylpropanoids in Archidasyphyllum and Dasyphyllum is here reported for the first time. [ABSTRACT FROM AUTHOR]

Abstract: A phytosociological study was conducted in a riparian forest of the Rio Paraguai near Corumbá and Ladário in the state of Mato Grosso do Sul, Brazil. The topographic distribution of species was correlated with durations of the river''s seasonal floodings and the cumulative time of flooding between 1974 and 1995. One hundred and eight contiguous 10×10m plots were systematically established. All individuals with more than 15cm of girth at breast height (gbh=1.3m) were sampled. A total of 695 individuals distributed among 37 species, 35 genera and 23 families were found. The Shannon index (H′) for species diversity was 2.7. The highest importance value (IV) was found for Inga vera ssp. affinis, followed by Triplaris gardneriana, Ocotea diospyrifolia, Crataeva tapia and Vochysia divergens. The plots were classified into two groups according to their distance from the margin, applying Ward''s method of classification and principal coordinate analysis (PCO) on the same Bray Curtis distance matrix. The topical environments were divided into four bands by Two-Way Indicator Species Analysis (TWINSPAN), and the species were also grouped into four groups. Flooding in these groups ranged from regular inundation in all 23 years of the historical series of the Ladário gauge to sporadic flooding for a maximum of 2 consecutive years. [Copyright &y& Elsevier]

Abstract The genus Eremanthus has been studied in the last decades from the taxonomic, phytochemistry and ecological perspectives, although the chemical composition of several of its species are still poorly known. In this work, some high polar chemical constituents of E. incanus was identified using a high-performance liquid chromatography analytical technique combined with sequential mass spectrometry (HPLC-ESI-MSn). The phytochemical investigation allowed the identification of 20 compounds in E. incanus , including different analogs of flavonoids, chlorogenic acids and glycosylated phenolic derivatives. All of these compounds are being described for the first time in E. incanus. The chemotaxonomic significance of chlorogenic acids, flavonoids and, especially, glycosylated phenolic derivatives in E. incanus has been summarized. This chemical profile was compared with another species of the genus Eremanthus (E. capitatus) and also with a species of another genus (Minasia alpestris) from Vernonieae subtribe. Highlights • Phytochemical investigation of Eremanthus incanus Less. leaves. • Identification of 20 compounds in E. incanus described here for the first time. • Comparison of chemical content of E. incanus with E. capitatus and M. alpestris. • Glycosylated phenolic derivatives might be chemomarkers of the genus Eremanthus. [ABSTRACT FROM AUTHOR]

Vernonia sensu lato is the largest and most complex genus of the tribe Vernonieae (Asteraceae). The tribe is chemically characterized by the presence of sesquiterpene lactones and flavonoids. Over the years, several taxonomic classifications have been proposed for Vernonia s.l. and for the tribe; however, there has been no consensus among the researches. According to traditional classification, Vernonia s.l. comprises more than 1000 species divided into sections, subsections and series ( sensu Bentham). In a more recent classification, these species have been segregated into other genera and some subtribes were proposed, while the genus Vernonia sensu stricto was restricted to 22 species distributed mainly in North America ( sensu Robinson). In this study, species from the subtribes Vernoniinae, Lepidaploinae and Rolandrinae were analyzed by UHPLC-UV-HRMS followed by multivariate statistical analysis. Data mining was performed using unsupervised (HCA and PCA) and supervised methods (OPLS-DA). The HCA showed the segregation of the species into four main groups. Comparing the HCA with taxonomical classifications of Vernonieae, we observed that the groups of the dendogram, based on metabolic profiling, were in accordance with the generic classification proposed by Robinson and with previous phylogenetic studies. The species of the genera Stenocephalum , Stilpnopappus , Strophopappus and Rolandra (Group 1) were revealed to be more related to the species of the genus Vernonanthura (Group 2), while the genera Cyrtocymura , Chrysolaena and Echinocoryne (Group 3) were chemically more similar to the genera Lessingianthus and Lepidaploa (Group 4). These findings indicated that the subtribes Vernoniinae and Lepidaploinae are non-chemically homogeneous groups and highlighted the application of untargeted metabolomic tools for taxonomy and as indicators of species evolution. Discriminant compounds for the groups obtained by OPLS-DA were determined. Groups 1 and 2 were characterized by the presence of 3′,4′-dimethoxyluteolin, glaucolide A and 8-tigloyloxyglaucolide A. The species of Groups 3 and 4 were characterized by the presence of putative acacetin 7- O -rutinoside and glaucolide B. Therefore, untargeted metabolomic approach combined with multivariate statistical analysis, as proposed herein, allowed the identification of potential chemotaxonomic markers, helping in the taxonomic classifications. [ABSTRACT FROM AUTHOR]

Abstract: Bignoniaceous woody species are very important ecological components of neotropical forests, but the reproductive biology of many species, such as Cybistax antisyphilitica, remains virtually unknown. Most species of Bignoniaceae are characteristically self-sterile, despite typically exhibiting normal pollen tube growth throughout the style, combined with slow rates of ovule penetration, fertilisation and endosperm initiation in selfed pistils. Uniform abortion occurs within a few days of anthesis, indicating the occurrence of late-acting self-incompatibility (LSI). However, breeding system studies have been performed in fewer than 7% of species, and other types of breeding systems (e.g., self-compatibility and apomixis) have been reported in this family. In the present study, the reproductive biology of C. antisyphilitica was investigated by field observation of flower visitors and floral events. Moreover, reproductive biology of this species was examined through experimental pollinations, analyses of pollen tube growth and ovule penetration using fluorescence microscopy, verification of pistil longevity, and a histological analysis of unpollinated vs. self-pollinated pistils. Finally, morphological aspects, quantities and germination were investigated in seeds that resulted from different pollination treatments. Natural pollination was effected by large- and medium-sized bees, and their visiting behaviour favours a high proportion of geitonogamy and no pollen limitation. Self-pollinated flowers produced no fruits, and all of the characteristic post-pollination events cited above were verified, witnessing the occurrence of LSI with post-zygotic rejection of selfed pistils in C. antisyphilitica. Although some indications of extended pistil longevity were found in selfed pistils, this feature seemed to be affected by unidentified environmental factors. The seeds were always monoembryonic and with high viability. A larger variation in the number of viable seeds was found in fruits derived from natural pollination. A low fruit set was observed after both natural and cross-pollination, and most crossed fruits underwent abortion at several points during the juvenile phase, even when protected against herbivory. The formation of surplus flowers/juvenile fruits and the apparently wasteful selfing mechanism control implied in LSI are discussed in the context of the perennial life style of tropical woody plant species. [Copyright &y& Elsevier]

Abstract: The pantropical weed Bidens pilosa (Asteraceae) is a species with several taxonomic problems. Recently it has been shown to be a complex of different species. To shed light on this problem in Brazil, dichloromethane extract of leaves of several populations corresponding to three proposed species for the complex in southeastern Brazil (B. pilosa, Bidens alba and Bidens subalternans) were analyzed by GC–MS. Twenty-four substances were detected, of which four resemble polyacetylenes, the others sesquiterpenes. Five sesquiterpenes tentatively identified as E-caryophyllene, α-humulene, germacrene-D, bicyclogermacrene and α-muurolene were found in all three Bidens species. The polyacetylene phenylhepta-1,3,5-triyne was identified only in B. alba. Multivariate analysis (cluster and principal component analyses) separated the three entities, suggesting that these compounds could represent a useful tool to distinguish species in the B. pilosa complex. [Copyright &y& Elsevier]

Lychnophora pinaster Mart. (Asteraceae) is endemic to the Brazilian Cerrado. It is distributed along the altitudinal gradient of the mountainous ranges of the state of Minas Gerais. This study aimed to evaluate the influence of altitude on the genetic diversity of L. pinaster populations and the effects of altitude and climatic factors on essential oil chemical composition. Essential oils from L. pinaster populations from the north (North 01, North 02, and North 03, 700–859 m) and the Metropolitan region of Belo Horizonte (MhBH 01 and MrBH 02, 1366–1498 m) were analyzed. SNP markers from L. pinaster in these regions and Campos das Vertentes (CV 01, CV 02, and CV 03, 1055–1292 m) were also analyzed. The main compounds in essential oils were 14-hydroxy-α-humulene (North 01 and North 03), cedr-8(15)-en-9-α-ol (North 02), 14-acetoxy-α-humulene (MrBH 01), and 4-oxo-15-nor-eudesman-11-ene (MrBH 02). Hierarchical cluster and heatmap analyses showed that the North and MrBH populations included five different groups, indicating the chemical composition of essential oils is distinct in each population. Furthermore, principal component analysis showed that higher altitudes (1366 m and 1498 m) in the MrBH influence the chemical composition of essential oils, and climatic factors determine the chemical composition in North region. The genetic diversity showed that most alleles are in Hardy–Weinberg equilibrium and imply high genetic variation and genetic polymorphisms between populations. Furthermore, the results of Mantel tests (R = 0.3861517; p = 0.04709529; R = 0.9423121; p = 0.02739726) also showed that higher altitude (>1360 m) shapes the genetic diversity at the MrBH. The genetic structure showed that higher altitudes (>1360 m) contribute to the structure of the MrBH populations, but not to North and CV populations. Therefore, the altitudinal ranges of Minas Gerais mountainous ranges determine the higher genetic and chemical diversity of L. pinaster populations. [Display omitted] • Lychnophora pinaster is a species found in the Brazilian Cerrado used in folk medicine. • Essential oils from Lychnophora pinaster populations show a correlation with altitude. • Essential oils are characterized by a high abundance of oxygenated sesquiterpenes. • The genetic diversity of Lychnophora pinaster populations were assessed by SNP markers. • Altitudinal range influences the genetic diversity of Lychnophora pinaster. [ABSTRACT FROM AUTHOR]