Eremanthus Erythropappus Research Articles

Development of a green Komagataella phaffii cell factory for sustainable production of plant-derived sesquiterpene (–)-α-bisabolol

(–)-α-Bisabolol is a plant-derived sesquiterpene derived from Eremanthus erythropappus, which can be used as a raw material in cosmetics and has anti-inflammatory function. In this study, we designed six mutation sites of the (–)-α-bisabolol synthase BOS using the plmDCA algorithm. Among these, the F324Y mutation demonstrated exceptional performance, increasing the product yield by 73 %. We constructed a de novo (–)-α-bisabolol biosynthesis pathways through systematic synthetic biology strategies, including the enzyme design of BOS, selection of different linkers in fusion expression, and optimization of the mevalonate pathway, weakening the branching metabolic flow and multi-copy strategies, the yield of (–)-α-bisabolol was significantly increased, which was nearly 35-fold higher than that of the original strain (2.03 mg/L). The engineered strain was capable of producing 69.7 mg/L in shake flasks. To the best of our knowledge, this is the first report on the biosynthesis of (–)-α-bisabolol in Komagataella phaffii, implying this is a robust cell factory for sustainable production of other terpenoids.

Variability in Eremanthus erythropappus (DC) MacLeish clones revealed by morphological and molecular markers

Variability in Eremanthus erythropappus (DC) MacLeish clones revealed by morphological and molecular markers

In Vitro Evaluation of Potentially Edible Brazilian Trees and Shrubs in Ruminant Nutrition

The present study aims to evaluate the nutritional value of different tree and shrub leaves in Brazilian ruminant production systems. Eight potentially edible trees and shrubs were identified from interviews with 30 ruminant producers: Aroeira (ARO; Lithraea molleoides), Black Mulberry (BMU; Morus nigra), Candeia (CAN; Eremanthus erythropappus), Jatobá (JAT; Hymenaea courbaril), Gliricídia (GLI; Gliricidia sepium), Santa Bárbara tree (SBT; Mélia azedarach), Tithonia (TIT; Tithonia diversifolia), and White Mulberry (WMU; Morus alba). Four leaf samples of each edible tree were sampled, and chemical analyses and in vitro assays were performed. Edible trees (except CAN and JAT) had lower neutral detergent fiber content than Mombasa grass. In addition, SBT, BMU, WMU, and TIT had lower fiber content than the other evaluated edible trees. Consequently, SBT, TIT, BMU, and WMU had improved dry matter degradation. Among the edible trees and shrubs, SMW and WMU increased the potential for gas production (a parameter). On the other hand, CAN decreased the estimated gas production 48 h after incubation. Furthermore, TIT decreased methane production up to 24 h after in vitro fermentation. Thus, except ARO, CAN, and JAT, the edible trees evaluated in the present study are potential feeds in moderate- to high-producing animals. Additionally, TIT fermentation reduces in vitro methane production.

Short-term increase in clonal propagules following disturbance in a natural population of Eremanthus erythropappus

Short-term increase in clonal propagules following disturbance in a natural population of Eremanthus erythropappus

The peculiar post-senescence in globoid stem galls triggered by fungi and arboreal ants on Eremanthus erythropappus (DC.) McLeisch (Asteraceae)

• The globoid stem galls under senescence can still react to biotic stimuli. • Ant movement in and out of the galls stimulate plant cell reactions. • The post-gall senescence reveals a reassumption of plant cell cycles. • The gall-ant-fungi interaction promotes a particular case of post-gall senescence. • Empty galls enter senescence for they close after the escape of the galling insect. Eremanthus erythropappus (DC.) McLeisch (Asteraceae), popularly known as “candeia”, is a common species in Minas Gerais state – Brazil and hosts six gall morphotypes. Our focus relies on the diagnosis of how one of these morphotypes, i.e., globoid stem galls induced by Neolasioptera sp. (Diptera: Cecidomyiidae) in the senescent stage can still react to the biotic stimuli of ants and fungi. These senescent globoid galls can be found in two forms: (1) empty galls characterized by the exit channel scar closed by plant tissue development, and (2) ant-occupied galls characterized by open exit channels, and the gall chamber occupied by ants and fungi. We hypothesize that the anatomical profile of senescent galls on E. erythropappus may favour the formation of peculiar ant-nest galls. The anatomical analyses revealed that phellogen activity along the exit channel completely closes the empty-galls after the escape of the galling Neolasioptera sp. The ant-occupied galls host seven different genera of ants, whose movement in and out of the gall may prevent the closing of the exit channel and allow the invasion of opportunistic fungal hyphae. The gall-ant-fungi interaction relies on the ants mechanically maintaining the opening of the exit channel previously dug by the galling Neolasioptera , while the fungi stimulate the metabolism of the cells in gall tissues. This interaction between E. erythropappus , fungi and ants, is responsible for the tissue responses and the maintenance of the peculiar ant-nest galls.

Hydrogel influences in Eremanthus erythropappus establishment in different hydric handlings

Hydrogel influences in Eremanthus erythropappus establishment in different hydric handlings

Vascular traits of stem galls: Cell increment versus morphogenetic constraints in wood anatomy.

Eremanthus erythropappus hosts globoid stem galls induced by Neolasioptera sp. (Diptera: Cecidomyiidae) close to the stem apex, which do not compromise the shoot apical meristem (SAM). We hypothesize that maintenance of the SAM, as well as the increasing number of leaves per branch and of galled stem lengths and diameters, are a consequence of alterations in vascular cells and, consequently, in the priority for water flow from non-galled stems to the stem galls. Our study focuses on the globoid stem galls to evaluate if gall induction and development promote changes in structure and function of secondary xylem cells. Anatomical, cytological, histometric and physiological methods were used to analyse non-galled stem branches (NGS), mature globoid stem galls and stem portions below and above the galls. These analyses revealed that vessel elements are larger in stem galls and in stem portions above the galls. Under Neolasioptera sp. induction activity, the vascular cambium of E. erythropappus produces less numerous but larger vessel elements and overproduces parenchyma cells. Contrary to the vascular constriction hypothesis proposed for bacterial galls, the vascular traits of the Neolasioptera sp. stem galls on E. erythropappus result in priority for water flow to galls and the non-galled portions above the galls, allowing the maintenance of galled stem growth and development.

Allelopathic potential of the extracts of non-galled stems and globoid stem galls of Eremanthus erythropappus (DC) McLeish (Asteraceae)

Eremanthus erythropappus (DC) McLeisch (Asteraceae), commonly known as “candeia”, is a native species of Minas Gerais state, Brazil, frequently used in medicine as an anti-inflammatory and antimicrobial agent. Eremanthus erythropappus hosts six different gall morphotypes, whose associated inducers manipulate plant cells and tissues and stimulate the neo-synthesis, maintenance, or inhibition of both primary and secondary metabolites on their host plant organs. Based on the premise that galls can potentialize the chemical composition of their associated host plants, our study investigated the allelopathic potential of methanolic extracts of E. erythropappus non-galled stems and globoid stem galls on Lactuca sativa seeds. We also studied the anatomical alterations induced on lettuce plantlets submitted to the methanolic extracts to describe diagnostic features related to the allelopathic effect. Five pentacyclic triterpenes constituted the major class of the identified compounds, followed by volatile oils, alkane hydrocarbons, alkanes, and ketones. The germination rates were statistically different between the treatments, and among the treatments, and the controls (water and methanol). The pentacyclic triterpenes of the extracts of the non-galled stems and the stem galls have a powerful allelopathic effect on the germination of L. sativa; a higher effect than that of the sesquiterpenes of the essential oils previously described for the leaf chemical compounds. The galling Neolasioptera sp. activity on E. erythropappus stems elicited the synthesis and accumulation of new chemical compounds, two triterpenes (ɤ-taraxasterol, and β-amyrone) and one alkane (tricosane), and inhibited the synthesis of compounds previously related to extracts of E. erythropappus stems, i.e., two triterpenes (A-neooleana-3(5),12-diene, and lupenone) and one ketone (2(1H)naphthalenone). These extracts altered the differentiation of root parenchyma cells of L. sativa germinated plantlets, but our premise was not corroborated as the galling activity did not potentialize the allelopathic effects.

Do bird communities of neotropical monodominant forests have their own identity? The case of Eremanthus erythropappus forests

Background: Monodominant Eremanthus erythropappus forests are dispersed in neotropical montane regions of southeastern and northeastern Brazil, forming ecotonal areas among other high altitude phytophysiognomies, with no information from their fauna communities and how these communities vary between phytophysiognomies adjacent. We examined the bird community of three preserved and three managed E. erythropappus forests, and compared them two other coexisting phytophysiognomies (cloud forests and montane fields), being three samples of each, in an ecotonal region between two biodiversity hotspot domains (Cerrado and Atlantic Forest), in southeastern Brazil (1300 to 1570m high). Results: The bird community of the natural E. erythropappus forests was shared with other vegetation, while the managed E. erythropappus forests presented the lowest species richness. However, even though managed E. erythropappus forests has almost no exclusive elements, their community caused a balanced variation (a set of very similar species, only changing the representativeness), suggesting that the abundance of the registered species varies along these phytophysiognomies. Conclusion: The species associated with the natural E. erythropappus forests represented 50% of the total species, in contrast to the remaining 50% associated with the areas of cloud forests and montane fields, and their sharing behaves as an ecotonal community, since its community coincides with elements which are also present in the avifauna of the other two sampled phytophysiognomies. The composition of the avifauna from managed E. erythropappus forests was more similar to the community registered in the montane fields.

Metal bioaccumulation alleviates the negative effects of herbivory on plant growth

Metalliferous soils can selectively shape plant species’ physiology towards tolerance of high metal concentrations that are usually toxic to organisms. Some adapted plant species tolerate and accumulate metal in their tissues. These metals can serve as an elemental defence but can also decrease growth. Our investigation explored the capacity of natural metal accumulation in a tropical tree species, Eremanthus erythropappus (Asteraceae) and the effects of such bioaccumulation on plant responses to herbivory. Seedlings of E. erythropappus were grown in a glasshouse on soils that represented a metal concentration gradient (Al, Cu, Fe, Mn and Zn), and then the exposed plants were fed to the herbivores in a natural habitat. The effect of herbivory on plant growth was significantly mediated by foliar metal ion concentrations. The results suggest that herbivory effects on these plants change from negative to positive depending on soil metal concentration. Hence, these results provide quantitative evidence for a previously unsuspected interaction between herbivory and metal bioaccumulation on plant growth.

Rescue and vegetative propagation of Eremanthus erythropappus (DC.) MacLeish in natural stand.

The native stands of 'candeia' (Eremanthus erythropappus) have been explored through management plans due to the economic potential of essential oil. The rescue of adult trees, as well as the application of silvicultural techniques that favor the restoration of the stand, can contribute to the genetic conservation of this species. This study's objective was to assess the efficiency of propagation techniques for the rescue of 26 matrices of 'candeia' in a natural managed stand and discussion about the rhizogenesis. In August 2017, trees were induced to regrowth by coppice, followed by exposure and scarification of roots. The emergence of shoots and morphology were evaluated according to the origin (i.e., stump or root). After that period, 19 matrices had their sprouts collected for the preparation of apical cuttings. Indole-3-butyric acid (IBA) was applied at the base of the cuttings. Cutting survival at greenhouse exit (GE), rooting at shade house exit (SHE), morphology and root anatomy were evaluated. In 189 days, the scarification of roots promoted 76.92% of budding. The percentage of sprouted matrices, number of shoots per matrice, length, diameter, and shoot length/diameter ratio increased over time. Only 12.2% of the cuttings survived in GE, and of these, 7.9% rooted in SHE. The cutting resulted in the formation of a clonal mini-garden of 'candeia', with seven of the 19 matrices submitted to propagation. The anatomical analyses showed that bud formation occurs from cell redifferentiation in the phloem parenchyma, and presence of crystals on the walls of the vessel elements of the secondary xylem. The shoots induction from scarification of roots could be used as a silvicultural practice for the reestablishment of the native fragments handle.

(-)-α-Bisabolol Production in Engineered Escherichia coli Expressing a Novel (-)-α-Bisabolol Synthase from the Globe Artichoke Cynara cardunculus var. Scolymus.

(-)-α-Bisabolol is a functional ingredient in various health and cosmetic products and has antibacterial, anti-inflammatory, and wound healing properties. (-)-α-Bisabolol is chemically synthesized and produced by steam distillation of essential oils extracted from Brazilian Candeia (Eremanthus erythropappus). To sustainably produce pure (-)-α-bisabolol, we previously engineered Escherichia coli to produce 9.1 g/L (-)-α-bisabolol via heterologous mevalonate pathways and (-)-α-bisabolol synthase (BOS) from German chamomile, Matricaria recutita (MrBOS). BOS has only been reported in MrBOS and Brazilian Candeia (EeBOS). The limited availability of BOS has made it difficult to achieve high titer and yield and large-scale (-)-α-bisabolol production. We identified a novel BOS in globe artichoke (CcBOS) and examined its functionality in vitro and in vivo. CcBOS showed higher catalytic efficiency and (-)-α-bisabolol production rates than those from MrBOS or EeBOS. In fed-batch fermentation, CcBOS generated the highest reported (-)-α-bisabolol titer to date (23.4 g/L). These results may facilitate economically viable industrial (-)-α-bisabolol production.

Vacant rooms? The secondary use of stem-galls by ants in Eremanthus erythropappus (Asteraceae)

Galls are atypical proliferations of plant tissue induced by highly specialized herbivores, such as some insect groups. Although gall inducers create these structures for their own purpose (food, habitat, protection against natural enemies, and harsh weather), many other organisms can use galls as secondary inhabitants. The creation of new and better habitats with ameliorated micro-environmental conditions allows for the use of many other organisms, and as such, some galling insects are considered "micro" ecosystem engineers. This study characterized the occurrence of ants in microhabitats created by a gall-inducing cecidomyiidae associated with Eremanthus erythropappus (DC.) Mac. Leish (Asteraceae). It was 153 individuals of ants belonging to three species in 19 galls (9.5%) from the 200 galls sampled. The most common ant species found was Myrmelachista gallicola Mayr (Formicinae), including a single queen and larvae individuals. Galls occupied by these ants were 11.5% larger compared to unoccupied galls (gall diameter: occupied galls - 10.00 ± 2.09 mm; unoccupied galls - 8.97 ± 1.90 mm). Abandoned galls might promote the diversity of other organisms, especially for opportunistic dwellers such as ants.

The enemy within: the effects of mistletoe parasitism on infected and uninfected host branches

To comprehend how mistletoes affect their host functioning is a key matter in plant ecology. As yet, it is not clear whether the impact of mistletoes is confined to infected branches or the entire host is compromised as well. Here, we compared leaf functional traits between branches infected by mistletoes (infected), uninfected branches yet close to mistletoe attachment (neighbour), and branches of trees without any mistletoe (control). Our model species pairs were Phoradendron crassifolium infecting Eremanthus erythropappus tree and Psittacanthus robustus infecting Vochysia thyrsoidea tree. The study was carried out in the Brazilian savannah, Cerrado. We found that neighbour branches of E. erythropappus suffered a greater reduction in specific leaf area compared to infected branches. Control branches occupied an intermediary position between infected and neighbour branches. On the other hand, both infected and neighbouring branches of V. thyrsoidea suffered a reduction in carbon assimilation rate compared to control trees. As far as we know, our study is the first to describe the presence of mistletoe affecting the healthy branches neighbouring the mistletoe attachment. This finding sheds light on the need to consider both infected and neighbouring branches when evaluating the effects of parasitism on tropical trees.

SEEDLINGS OF TREE SPECIES PRODUCED IN SUBSTRATES BASED ON ORGANIC COMPOSTS

The quality of the seedling produced is directly related to substrate composition, so it is essential to select constituents with adequate characteristics. The objective of this study was to evaluate Eucalyptus urophylla, Peltophorum dubium and Eremanthus erythropappus seedlings and to relate the physical and chemical characteristics of the formulated substrates to their quality. For each species, an experiment was carried out in a completely randomized design (CRD), consisting of five treatments, five replicates, and plots composed of 20 seedlings. In order to evaluate the quality of the seedlings, the biometric variables were measured and, as a qualitative analysis, the ease to remove the seedlings from the tubes (ERT) and root aggregation to the substrate (AGGR) were evaluated. Seedlings produced in the substrates formulated with alternative constituents showed higher values when compared to seedlings produced with commercial substrate, for most of the analyzed variables. Coffee husk can be applied in the production of seedlings of P. dubium and E. urophylla. For the formation of E. erythropappus seedlings, none of the formulations tested are recommended.

Title: priority areas for genetic conservation of Eremanthus erythropappus (DC.) MacLeish in Brazil

Eremanthus erythropappus (DC.) MacLeish, commonly known as candeia, is a threatened tree species that occurs in Seasonal Semideciduous Forests in Brazil. The tree is valued for the durability of its wood and essential oil production, from which the active agent (alpha-bisabolol) is used in pharmaceutical and cosmetic industries. Due to its high economic value, E. erythropappus has been exploited for several decades. Natural populations have been reduced, with the subsequent ecological and genetic negative impacts. We aimed to use a landscape genetics approach to identify if natural features influence the genetic diversity of E. erythropappus. In order to assess the genetic variability and provide information for the conservation of the species, genetics analyses were carried out for 200 individuals from ten natural populations of E. erythropappus. Nine ISSR primers produced 72 bands, of which 57 (79%) were polymorphic. Genetic diversity ( $${H}_{E}$$ ) was 0.30 and gene flow was 1.4 migrants per population. The Bayesian clustering model indicated the occurrence of four genetically distinct populations (K = 4). Results of AMOVA showed high genetic differentiation between populations (30.8 %) and there was positive correlation between genetic and geographic distances (r = 0.632, P = 0.001). Based on a Mantel correlation and the genetic discontinuity among populations, we recommend the implementation of four operational units to support the conservation of this species.

Effects of fluoride emission on the morphoanatomy of three plant species endemics to Brazil using passive biomonitoring.

Fluoride is the most phytotoxic atmospheric pollutant. The objective of this study was to evaluate the effects of fluoride emissions by an aluminum smelter on three plant species endemics to Brazil, located at Parque Estadual do Itacolomi (PEI). The monitored species were Byrsonima variabilis (Malpighiaceae), Myrceugenia alpigena (Myrtaceae), and Eremanthus erythropappus (Asteraceae), which were monitored during 9 months using passive biomonitoring at five different locations with different distances from the smelter. The monitored species did not show macroscopic phytotoxicity damage to fluoride; however, they did show microscopic damage. The species closer to the smelter presented more severe anatomic damages, such as rupture of cell walls, protoplast retraction, and trichome alterations. Damaged stomatal ledges, flaking epicuticular wax, and damages to trichomes were observed. M. alpigena showed a higher accumulation of fluoride than the other species at all monitored sites. The test for cell death with Evans Blue was positive for the three studied species. Through biomonitoring in the PEI, we concluded that the emissions from the aluminum smelter affect the native vegetation and that due to the greater accumulation of fluoride and the diversity of microscopic damage in M. alpigena, the use of this species in the monitoring of environments polluted by fluoride is enhanced.

Acaricidal activity of essential oils of Cinnamomum zeylanicum and Eremanthus erythropappus, major compounds and cinnamyl acetate in Rhipicephalus microplus.

This study aimed to chemically characterize the essential oils (EOs) of Cinnamomum zeylanicum (cinnamon) and Eremanthus erythropappus (candeia) and evaluate their acaricidal activity, together with that of their major compounds and cinnamyl acetate derivative, against Rhipicephalus microplus. Essential oil compounds were identified through gas chromatography. The larval packet test (LPT) at concentrations ranging from 0.31 to 10.0 mg/mL and the adult immersion test (AIT) at concentrations between 2.5 and 60.0 mg/mL were performed. (E)-cinnamaldehyde and α-bisabolol were the major compounds in cinnamon (86.93%) and candeia (78.41%) EOs, respectively. In the LPT, the EOs of cinnamon and candeia and the compounds (E)-cinnamaldehyde, α-bisabolol and cinnamyl acetate resulted in 100% mortality at concentrations of 2.5, 2.5, 5.0, 10.0 and 10.0 mg/mL respectively. In the AIT, percentage control values > 95% were observed for cinnamon and candeia EOs, (E)-cinnamaldehyde and α-bisabolol at the concentrations of 5.0, 60.0, 20.0, and 20.0 mg/mL, respectively, whereas cinnamyl acetate showed low activity. We conclude that EOs and their compounds showed high acaricidal activity, whereas the acetylated derivative of (E)-cinnamaldehyde presented less acaricidal activity on R. microplus engorged females.

Potencial uso da casca de café como constituinte de substrato para produção de mudas de espécies florestais

Na produção de mudas de espécies florestais há vários fatores que influenciam no seu crescimento. Dentre estes, um dos mais importantes é a composição do substrato. Nesse sentido, é essencial a seleção de bons constituintes que atendam a essa demanda. O objetivo deste trabalho foi avaliar o crescimento inicial de mudas de Eucalyptus urophylla, Peltophorum dubium e Eremanthus erythropappus, produzidas em diferentes formulações de substratos. Para cada espécie, foi instalado e conduzido um experimento, utilizando-se nas formulações os constituintes casca de arroz compostada, casca de café compostada, fibra de coco e substrato comercial. Os experimentos foram instalados em delineamento inteiramente casualizado (DIC), constituídos por oito tratamentos, cinco repetições e 20 mudas por parcela. Para avaliação da qualidade das mudas, aos 120 dias foram mensuradas as variáveis altura, diâmetro do coleto, peso de matéria seca da parte aérea, peso de matéria seca do sistema radicular e índice de qualidade de Dickson. Como análises qualitativas, foram avaliadas a facilidade de retirada das mudas do tubete e a agregação das raízes ao substrato. Os resultados encontrados após a avaliação atestaram que as mudas produzidas nos tratamentos formulados com casca de café compostada apresentaram valores superiores para a maioria das variáveis analisadas, quando comparado com as mudas produzidas nos tratamentos formulados com a casca de arroz e na testemunha. Para as três espécies, indica-se a utilização da proporção de 40% de casca de café compostada com 40% de substrato comercial e 20% de fibra de coco para composição do substrato.

Fine-scale analysis reveals a potential influence of forest management on the spatial genetic structure of Eremanthus erythropappus

Forest management may have significant effects on forest connectivity and natural population sizes. Harvesting old-growth single trees may also change natural patterns of genetic variation and spatial genetic structure. This study evaluated the impacts of forest management using a silvicultural system of seed trees on the genetic diversity and spatial genetic structure of Eremanthus erythropappus (DC.) MacLeish. A complete survey of 275 trees on four plots was undertaken out to compare the genetic variation of a managed stand with an unmanaged stand. We genotyped all adult and juvenile individuals 60 months after the management and compared the genetic diversity and the spatial genetic structure parameters. Genetic diversity was considered high because of an efficient gene flow between stands. There were no genetic differences between stands and no evidence of inbreeding. Genetic clustering identified a single population (K = 1), indicating no genetic differentiation between managed and unmanaged stands. Adult and juvenile individuals of the unmanaged stand were more geographically structured than individuals from the managed one. There was a tendency of coancestry among juveniles at the first class of distance of the managed stand, suggesting a drift of genetic structure possibly caused by management. Understanding early responses to management on genetic diversity and stand structure is a first step to ensuring the effectiveness of conservation practices of tree species. The sustainability of forest management of E. erythropappus on genetic diversity, and more accurately, on spatial genetic structure needs evaluation over time to promote effective conservation of the population size and genetic variability.