Bioinsecticide potential of Curcuma zedoaria rhizome essential oil

In this study  the potential bioinseticide of the essential oil (OE) extracted from the rhizomes of the species Curcuma zedoaria (Zingiberaceae) was evaluated. The rhizomes were collected during dormancy (winter) and budding (summer). The EO was obtained by hydrodistillation (2h) and identified by GC/MS. In addition, a multivariate exploratory analysis was done to determine the analysis of the major compounds (PCA). The EO yield in dormancy was 0.61± 0.07 (%) and in budding 0.55 ± 0.08 (%). The bioassays on Aedes aegypti larvae and pupae were done by immersion test at different EO concentrations which ranged from 500.00 to 0.003 mg mL-1 (v/v). The results on the larvae and pupae indicated LC99.9 of (0.01 and 1.38 mg mL-1) for EO in dormancy, and (0.08 and 2.63 mg mL-1) for EO during budding, respectively. The action mechanism of EOs in both periods was determined by autobiographic method evaluating the inhibitory potential on the acetylcholinesterase enzyme, indicating greater inhibition of the EO enzyme during dormancy (0.039 mg mL-1) when compared to the EO during budding (0.156 mg mL-1). The projection representation of the EO chemical classes in both evaluated periods indicated that oxygenated sesquiterpenes are the major compound class (46.99% in dormancy) and (43.59% in budding). The projection of major chemical compounds of EOs presented three compounds with greater mass flow distancing: epicurzerenone (18.20% and 12.10%); 1.8 cineole (15.76% and 12.10%) and β-elemene (4.43 and 0.01%) that are found in greater amounts in the dormancy EO when compared to budding, respectively. These results corroborate with the greater potential on Ae. aegypti larvae and pupae found for the dormancy EO. The results are promising because they show in which vegetative cycle phase C. zedoaria EO presents greater bioinsecticide potential

Antifungal activity of Gallesia integrifolia fruit essential oil.

Gallesia integrifolia (Phytolaccaceae) is native to Brazil and has a strong alliaceous odor. The objective of this study was to identify the chemical composition of G. integrifolia fruit essential oil and evaluate fungicidal activity against the main food-borne diseases and food spoilage fungi. The essential oil was extracted by hydrodistillation and identified by GC-MS. From 35 identified compounds, 68% belonged to the organosulfur class. The major compounds were dimethyl trisulfide (15.49%), 2,8-dithianonane (52.63%) and lenthionine (14.69%). The utilized fungi were Aspergillus fumigatus, Aspergillus niger, Aspergillus ochraceus, Aspergillus versicolor, Penicillium funiculosum, Penicillium ochrochloron, Penicillium verrucosum var. cyclopium, and Trichoderma viride. Minimal fungicidal concentration for the essential oil varied from 0.02 to 0.18mg/mL and bifonazole and ketoconazole controls ranged from 0.20 to 3.50mg/mL. The lower concentration of the essential oil was able to control P. ochrochloron, A. fumigatus, A. versicolor, A. ochraceus and T. viride. This study shows a high fungicidal activity of G. integrifolia fruit essential oil and can support future applications by reducing the use of synthetic fungicides

Schinus terebinthifolius essential oil and fractions in the control of Aedes aegypti

Several technologies have been developed to control Aedes aegypti, mainly studies on isolated plant molecules. The Schinus terebinthifolius (Raddi) (Anacardiaceae), popularly known as pink pepper is a plant widely used in reforestation of degraded areas and its fruits are used as condiments. The objective of this work was to investigate the potential of essential oils (EOs) and fractions (FRs) obtained from fresh fruits and leaves of S. terebinthifolius. The EOs were obtained by hydrodistillation (2 hours), fractionated on a chromatographic column using as the stationary phase silica gel 60 (0.063-0.2mm), mobile phases: n-hexane, dichloromethane, ethyl acetate and methanol and chemically evaluated by gas chromatography coupled to mass spectrometer (GC/MS). EOs and FRs were tested against larvae of the third stage and pupae of  Ae. aegypti by Immersion Test at concentrations ranging from 500.00 to 0.003 mg mL-1 (v/v). The hexane FRs obtained from fruits and leaves were the ones that showed the greatest activity on the larvae (LC99.9= 0.60 mg mL-1 and LC99.9 0.64 mg mL-1, respectively) and pupae (LC99,9 = 2.51 mg mL-1 and 2.61 mg mL-1, respectively). These results were confirmed by the anticholinesterase activity where the hexane (fruit and leaf) FRs presented the highest inhibitory potential on the acetylcholinesterase enzyme (0.156 mg mL-1 and 0.312 mg mL-1, respectively), suggesting the likely mechanism of action. The larvicidal potential can be explained by the presence of the major compounds bicyclogermacrene and germacrene D in the hexane FRs, indicating in this way that they may replace or even act in synergisms with conventional chemical larvicides. In this way the present study opens the field for new researches, aiming the development of products with the compounds bicyclogermacrene and germacrene D, as an alternative in the control of this culicide

Antimicrobial activity of Asteraceae species against bacterial pathogens isolated from postmenopausal women.

PURPOSE:Investigation of the antibacterial action of aqueous extracts of Bidens sulphurea, Bidens pilosa, and Tanacetum vulgare, species of Asteraceae family that are popularly used for the treatment of genito-urinary infection. METHODS:The minimum inhibitory concentration (MIC) and minimal bacterial concentration (MBC) of the extracts against standard strains of Staphylococcus aureus (ATCC25923), Enterococcus faecalis (ATCC29212), Escherichia coli (ATCC25922), and Pseudomonas aeruginosa (ATCC27853) and against bacteria that were isolated from cultures of vaginal secretions and urine from menopausal women with a diagnosis of recurrent urinary tract infections (rUTI) were determined by broth microdilution. RESULTS:The MIC values of the three extracts against Gram-positive and Gram-negative standard bacterial strains ranged from 7.81 to 125.00 mg ml-1, and the MBC values ranged from 7.81 to 500.00 mg ml-1. However, B. sulphurea was more efficient. In the urine samples, the three extracts inhibited the growth of coagulase-negative Staphylococcus spp., and the B. pilosa was the most active extract against E. coli compared with the other ones. For the vaginal secretion samples, no significant differences in the inhibition of coagulase-positive Staphylococcus spp. and P. mirabilis were found among the extracts. T. vulgare and B. sulphurea were more effective in inhibiting coagulase-negative Staphylococcus spp. compared with B. pilosa. E. coli was more susceptible to the B. sulphurea extract compared with the B. pilosa and T. vulgare extracts. CONCLUSION:The present results suggested the potential medicinal use of Asteraceae species, especially B. sulphurea, as therapeutic agents against rUTI-related bacteria