Chemical composition and biological activity of Baccharis erioclada DC. essential oil

Abstract The chemically complex essential oils of Baccharis species are associated with several biological activities, such as antimicrobial and antiulcerous properties. However, few studies have investigated Baccharis erioclada DC. Therefore, in this study, we aimed to characterize the essential oil of B. erioclada and evaluate its antioxidant, antimicrobial, and hemolytic potential. The essential oil was extracted by hydrodistillation using a Clevenger apparatus and analyzed via gas chromatography-mass spectrometry (GC-MS). Phosphomolybdenum complex formation, reducing antioxidant power, and thiobarbituric acid reactive substances (TBARS) methods were used to determine antioxidant potential. To evaluate the essential oil's antimicrobial activity, minimum inhibitory concentrations (MIC) in Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans were calculated. Hemolytic activity was determined in sheep red blood cells. Thirty-one compounds were identified via GC-MS analysis, representing 81.60% of the total essential oil. These compounds included: turmerone (27.97%), fokienol (13.47%), ledol (9.78%), and santalol (5.35%). The class of compounds identified was the oxygenated sesquiterpenes (62.52%). Antioxidant activity was confirmed via phosphomolybdenum complex formation and TBARS methods. Moderate antimicrobial activity and low hemolysis rates were displayed at concentrations of 250 and 500 µg/mL

Foliar anatomy and microscopy of six Brazilian species of Baccharis (Asteraceae).

We report for the first time the presence of cluster crystals of calcium oxalate within the glandular trichomes and oil bodies in the mesophyll for Baccharis species. Moreover, the comparative leaf anatomy and micro-morphology of six species of Baccharis, namely B. illinita, B. microdonta, B. pauciflosculosa, B. punctulata, B. reticularioides, and B. sphenophylla is investigated by light and scanning electron microscopy. The studied species exhibited differences in their leaf anatomical features such as the morphology of the cuticle, type and occurrence of the stomata, presence or absence of glandular trichomes, shape of the flagelliform trichomes, and the arrangement of the mesophyll tissues. These differences can be helpful in the species identification and classification and could represent informative characters for the reconstruction of the evolution of the genus.

Phenotypic plasticity and similarity among gall morphotypes on a superhost, Baccharis reticularia (Asteraceae).

Understanding factors that modulate plant development is still a challenging task in plant biology. Although research has highlighted the role of abiotic and biotic factors in determining final plant structure, we know little of how these factors combine to produce specific developmental patterns. Here, we studied patterns of cell and tissue organisation in galled and non-galled organs of Baccharis reticularia, a Neotropical shrub that hosts over ten species of galling insects. We employed qualitative and quantitative approaches to understand patterns of growth and differentiation in its four most abundant gall morphotypes. We compared two leaf galls induced by sap-sucking Hemiptera and stem galls induced by a Lepidopteran and a Dipteran, Cecidomyiidae. The hypotheses tested were: (i) the more complex the galls, the more distinct they are from their non-galled host; (ii) galls induced on less plastic host organs, e.g. stems, develop under more morphogenetic constraints and, therefore, should be more similar among themselves than galls induced on more plastic organs. We also evaluated the plant sex preference of gall-inducing insects for oviposition. Simple galls were qualitative and quantitatively more similar to non-galled organs than complex galls, thereby supporting the first hypothesis. Unexpectedly, stem galls had more similarities between them than to their host organ, hence only partially supporting the second hypothesis. Similarity among stem galls may be caused by the restrictive pattern of host stems. The opposite trend was observed for host leaves, which generate either similar or distinct gall morphotypes due to their higher phenotypic plasticity. The Relative Distance of Plasticity Index for non-galled stems and stem galls ranged from 0.02 to 0.42. Our results strongly suggest that both tissue plasticity and gall inducer identity interact to determine plant developmental patterns, and therefore, final gall structure.

Carqueja (Baccharis trimera): utilização terapêutica e biossíntese / Broom (Baccharis trimera): therapeutic use and biosynthesis

A utilização de plantas medicinais no tratamento e cura de enfermidades é um recurso terapêutico muito antigo e talvez o único adotado em muitas comunidades e grupos étnicos. A família Asteraceae concentra grande número de espécies com potencial terapêutico, algumas das quais do gênero Baccharis, utilizadas na medicina popular e também na produção de fitoterápicos. Estudos relatam que a principal indicação terapêutica mencionada para estas espécies estão relacionadas com ações sobre o trato gastrintestinal. A partir de pesquisa bibliográfica, foram identificadas as características morfológicas da carqueja, bem como, as propriedades terapêuticas cientificamente comprovadas, biossíntese dos principais metabólitos secundários, e possíveis interações medicamentosas.

The use of medicinal plants to treat and cure diseases is a very old therapeutic resource and perhaps the only one adopted in many communities and ethnic groups. The Asteraceae family concentrates a great number of species with therapeutic potential, some of which belong to the Baccharis genus and have been used in folk medicine and herbal medicine production. Studies have reported that the main therapeutic indication for these species is related to actions on the gastrointestinal tract. From literature searches, the morphological characteristics of broom, its scientifically proven therapeutic properties, as well as biosynthesis of secondary metabolites and possible drug interactions were identified.

Genetic variation within a dominant shrub species determines plant species colonization in a coastal dune ecosystem.

The diversity and structure of plant communities is often determined by the presence and identity of competitively dominant species. Recent studies suggest that intraspecific variation within dominants may also have important community-level consequences. In a coastal dunes ecosystem of northern California, we use a decade-old common garden experiment to test the effects of a genetically based architectural dimorphism within a dominant native shrub, Baccharis pilularis, on plant colonization success and understory plant diversity. We found that erect Baccharis morphs had higher richness and cover of colonizing plant species (both native and exotic species) compared to prostrate morphs, as well as higher biomass of a dominant exotic dune grass (Ammophila arenaria). Trait differences between architectural morphs influenced the abiotic understory environment (light availability, soil surface temperature, and litter depth) and were associated with species colonization success. Taken together, our results demonstrate that incorporating within-species variation, particularly within dominant species, into community ecological research can increase the ability to predict patterns of species diversity and assembly within communities.

Análise morfoanatômica comparativa de duas espécies de carqueja: baccharis microcephala DC. e B. trimera (Less) DC., asteraceae / Morphoanatomical comparative analysis of two species of shrub baccharis microcephala DC. and B. trimera (Less) DC., asteraceae

A identificação de espécies de Baccharis que são constituídas de cladódios, ou seja, caules alados, apresenta dificuldades até mesmo para especialistas em taxonomia vegetal. Baccharis microcephala e B. trimera pertencem ao grupo Trimera e são conhecidas vulgarmente como carquejas. Na medicina popular, é comum o uso de espécies aladas para a aplicação terapêutica como diurético, hepatoprotetor e digestivo. Baccharis trimera consta na F. Bras. IV e possui atividades antiinflamatória, analgésica, bacteriostática, bactericida e antidiabética. As espécies B. trimera e B. microcephala são frequentemente confundidas e utilizadas pela população para as mesmas finalidades terapêuticas. Objetivou-se estudar a morfologia externa e a anatomia dos cladódios dessas espécies, com a finalidade de se obterem dados que auxiliem na diferenciação e consequentemente na identificação das mesmas, contribuindo para o controle de qualidade de fitoterápicos, além de auxiliar na caracterização do grupo taxonômico. O material botânico foi submetido às microtécnicas fotônica e eletrônica de varredura usuais. As duas espécies são trialadas, sendo que em B. microcephala as alas são estreitas, praticamente contínuas em toda a extensão caulinar, enquanto que em B. trimera as alas são mais largas e interrompidas. As características morfológicas permitem a diferenciação dessas duas espécies, principalmente os tricomas tectores.

The identification of Baccharis spp. which have cladodes, defined as winged stems, brings difficulties even for taxonomists. Baccharis microcephala and B. trimera belong to the Trimera group and are known as carquejas. In folk medicine, it is common the use of winged species for the same therapeutic indication, such as diuretic, hepatoprotective and digestive. The monograph of B. trimera is included in the F. Bras. IV and this species shows anti-inflammatory, analgesic, bacteriostatic, bactericidal and antidiabetic activities. The species B. trimera and B. microcephala are alike and used by the population for the same therapeutic purposes. This work has aimed to study the external morphology and anatomy of the cladodes of these species, in order to contribute to the quality control of phytotherapic agents, as well as supply information for the taxonomic group. The botanical material was prepared for light and scanning electron microtechniques. Both species are three-winged, although the stem wings are narrow and nearly continuous in B. microcephala while in B. trimera they are wider and interrupted. The morphological characters and mainly the non-glandular trichomes allow these species to be distinguished.

Plant architecture and meristem dynamics as the mechanisms determining the diversity of gall-inducing insects.

Plant architecture is considered to affect herbivory intensity, but it is one of the least studied factors in plant-insect interactions, especially for gall-inducing insects. This study aimed to investigate the influence of plant architecture on the speciose fauna of gall-inducing insects associated with 17 species of Baccharis. Five architectural variables were evaluated: plant height, number of fourth-level shoots, biomass, average level and number of ramifications. The number of galling species associated with each host plant species was also determined. To test the effects of plant architecture on gall richness at the individual level, we used another data set where the number of fourth-level shoots and gall richness were determined for B. concinna, B. dracunculifolia, and B. ramosissima every 3 weeks during 1 year. The average similarity between host species based on gall fauna was low (9%), but plants with the same architectural pattern tended to support similar gall communities. The most important architectural trait influencing gall richness at the species level was the number of fourth-level shoots, which is indicative of the availability of plant meristems, a fundamental tissue for gall induction and development. This variable also showed a positive correlation with gall richness at the individual level. We propose that variations in gall richness among host species are driven by interspecific differences in plant architecture via availability of young, undifferentiated tissue, which is genetically controlled by the strength of the apical dominance. Plant architecture should have evolutionary consequences for gall communities, promoting insect radiation among architecturally similar plants through host shift and sympatric speciation. We also discuss the role of plant architecture in the global biogeography of gall-inducing insects.

Analysis of propolis from Baccharis dracunculifolia DC. (Compositae) and its effects on mouse fibroblasts.

This paper confirms Baccharis dracunculifolia DC. (Compositae) as the main botanical source of the propolis from southeastern Brazil (state of São Paulo) investigated to ascertain specific biological activity in relation to mouse NIH-3T3 fibroblasts, skin cells directly involved in the cicatrization processes. Flavonoid and total phenolic compounds were determined by spectrophotometry, and chemical composition by HPLC; the chromatographic profile, characterized largely by flavonoids and aromatic acids, was found to be qualitatively similar to that of Baccharis dracunculifolia DC. The adsorption of phenolic compounds in the propolis to skin powder was also investigated, and 68% of these compounds adsorbed to the skin powder. At concentrations from 0.12 to 7.81 microg/ml, the propolis revealed no statistical significant differences from its control solutions; however, at concentrations of 31.25 microg/ml or more, the propolis was toxic to NIH-3T3 cells. Thus, the propolis from Baccharis dracunculifolia DC. (Compositae) presents an in vitro concentration-dependent toxicity on mouse NIH-3T3 fibroblasts.