Search

Baccharis dracunculifolia is a medicinal plant native to southeastern Brazil and is the main botanical source used by bees (Apis mellifera) in the manufacture of green propolis and display similar gastroprotective action and chemical profile. This article reports the healing gastric ulcer activity of the hydroethanolic extract of B. dracunculifolia (HEBD) in an acetic acid‐induced ulcer model. In addition to the extract, the isolated compounds ferulic acid, p‐coumaric acid, caffeic acid, baccharin, and aromadendrin‐4'‐O‐methyl ether were also assayed. HEBD at a dose of 300 mg/kg reduced the ulcerated area by 49.4% after treatment for 7 days, twice a day. Histological analyses revealed that the margins and base of the ulcer obtained significant regeneration, and periodic acid Schiff base staining showed a 78.2% increase in the mucin levels. The action on the enzymatic antioxidant system demonstrated an increased activity of superoxide dismutase and glutathione‐S‐transferase, in addition to raising glutathione reduced levels and myeloperoxidase activity. HEBD did not show cytotoxicity in the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenylterazole bromine test. In vitro, HEBD inhibited the H+/K+‐ATPase enzyme and showed antioxidant activity in the 2,2 diphenyl‐1‐picryllydrazyl test. Regarding the isolated compounds, oral administration of p‐coumaric acid (15 mg/kg) reduced the ulcerated area by 66.2%. The results suggest that HEBD recovers the gastric ulcerated tissue, raising mucus and antioxidant enzyme levels, and reducing the H+/K+‐ATPase activity. In addition, the findings confirm that p‐coumaric acid is a pivotal bioactive compound on the gastric healing effects elicited by HEBD. © 2019 BioFactors, 45(3):479–489, 2019 [ABSTRACT FROM AUTHOR]

The article presents a study which evaluates the effects of Baccharis dracunculifolia ethyl acetate extract (Bd-EAE) to the Chinese hamster lung fibroblasts through comet assay. It says that B. dracunculifolia is the main botanical source of green propolis used as an anti-inflammatory agent to treat gastrointestinal diseases in folk medicine. Methods include evaluation of genotoxicity and antigenotoxicity. Results show chemopreventive activity of Bd-EAE which occurs under various mechanism.

• Premise of the study: Baccharis dracunculifolia (Asteraceae) is a native plant of the Atlantic Forest that is used for the production of essential oil. Microsatellite markers were developed for this species to investigate the genetic diversity of three natural populations. • Methods and Results: Seventeen out of 27 microsatellite loci identifi ed in a genomic library used for the characterization of 315 individuals derived from three natural populations of B. dracunculifolia resulted in successful amplifi cations. Eleven polymorphic loci, ranging from two to seven alleles per locus, were obtained with expected and observed heterozygosity values ranging between 0.068 and 0.775 and 0.046 and 0.667, respectively. • Conclusions: The microsatellite loci described in this study are tools that can be used for further studies of population genetics of B. dracunculifolia with a focus on deforested areas and conservation of natural populations. [ABSTRACT FROM AUTHOR]

1. The relative importance of direct and indirect interactions in controlling organism abundance is still an unresolved question. This study investigated the role of the direct and indirect interactions involving ants, aphids, parasitoids, and the host plantBaccharis dracunculifolia(Asteraceae) on a galling herbivoreBaccharopelma dracunculifoliae(Homoptera: Psyllidae).2. The effects of these interactions on the galling herbivore's performance were evaluated by an exclusion experiment during two consecutive generations of the galling insect.3. Ants had a direct negative effect on the performance of the galling herbivore by reducing the number of nymphs per gall. In contrast, ants had no indirect effects on gall mortality through the associated parasitoids.4. Aphids negatively affected gall development, suggesting that galls and aphids might be partitioning photoassimilates and nutrients moving throughout host-plant tissues.5. In addition, galls that developed during the rainy season were heavier, indicating that variation in the host plant, due to weather changes, can affect the development ofB. dracunculifoliaegalls. However, variation in the development ofB. dracunculifoliaegalls due to presence of aphids or the weather changes did not affect parasitoid attack.6. These results suggest that direct interactions between ants and galls influenced galling insect abundance, whereas numerical indirect effects involving galling insects, ants, aphids, and host plants were less conspicuous. [ABSTRACT FROM AUTHOR]

Summary 1. The pattern of attack by the leaf-galling insect Neopelma baccharidis (Homoptera: Psyllidae) was studied in three populations of the dioecious shrub Baccharis dracunculifolia (Asteraceae) in south-eastern Brazil. The plant vigour hypothesis, which predicts higher rates of attack and increased herbivore performance on the longest plant shoots, was tested. This work also provides further information for the study of differential herbivory in dioecious plants. 2. In total, 9200 shoots were collected randomly from 46 male and 47 female plants belonging to the three populations. Shoot length, number of leaves per shoot, rate of galling, and survival of psyllids did not differ between male and female plants. Another population on the Campus of the Federal University of Minas Gerais was used only to determine the pattern of shoot growth. 3. The hypothesis of sex-mediated herbivory was not corroborated in this study. 4. The frequency of galling increased with increasing shoot length, as predicted by the plant vigour hypothesis. Nevertheless, the number of oviposition sites (leaf buds) increased with shoot length. 5. The performance of the galling herbivore was not related to shoot length in the plant populations studied. 6. In conclusion, Neopelma baccharidis did not select shoots based on length only. [ABSTRACT FROM AUTHOR]

Abstract In this study, the mortality factors acting upon the galling psyllid Neopelma baccharidis Burckhardt (Homoptera) caused by its host plant, Baccharis dracunculifolia De Candole (Asteraceae) were analysed. In March 1999, 982 galls of the same cohort were randomly marked on 109 individuals of B. dracunculifolia in the field. Galls were censused each month during their development, from April to August, and dead galls were collected and analysed for mortality factors. Gall dehiscence rates were calculated for each month. The major mortality source of N. baccharidis was gall dropping (13.2% of the original cohort), which is probably a normal outcome of previous mortality caused by the other factors observed in this study. Unknown factors killed 11.7% of this gall population and were ascribed to plant resistance during gall development. Empty galls represented 7.7% of the observed mortality and may be a consequence of egg retention or egg mortality/abortion related to variations in plant quality. Shoot mortality was high during the dry season and killed 7.5% of the galls, but this impact was minimized after the third month from gall formation due to the ability of nymphs to accelerate development and emerge from galls on dying shoots. However, the size of dehisced galls on dead shoots tended to be smaller, possibly affecting adult performance. Mortality of N. baccharidis attributed to B. dracunculifolia strongly controlled the galling insect population, killing 40.7% of the original cohort of galls. Plant-mediated mortality was caused by often neglected factors acting predominantly during the first 3 months of development, which are critical to gall survivorship. These results reinforce the importance of bottom-up forces in plant-insect systems. [ABSTRACT FROM AUTHOR]