Plant extracts to control Alternaria alternata in Murcott tangor fruits.

Background: Alternaria alternata causes the Alternaria brown spot disease (ABS) in many tangerines and their hybrids worldwide. Plant extracts offer an alternative method for controlling this disease, which control is based on chemical fungicides.

Aims: To identify plant species with antifungal properties against A.

Evaluation of native and exotic Brazilian plants for anticancer activity.

Native and exotic Brazilian plants collected in the State of Minas Gerais were evaluated for their anticancer potential. Methanol extracts from leaves of 51 plant species were tested for cytotoxicity against four tumor cell lines: B16 (murine skin), HL-60 (human leukemia), MCF-7 (human breast), and HCT-8 (human colon). Plant extracts that exhibited IC(50) values less than 30 microg/ml against any tumor cell line were tested on sea urchin egg development and mouse erythrocytes.

Identification of the antimicrobial substances produced by Solanum palinacanthum (Solanaceae).

To find out natural antimicrobial agents as alternative in therapeutics and to preserve food, the methanol extract of Solanum palinacanthum aerial parts was submitted to purification steps guided by antibacterial and antifungal assays. As a consequence, the flavonoid rutin and 3,5-dicaffeoylquinic acid were isolated by column chromatography and high performance liquid chromatography, and identified by mass and nuclear magnetic resonance spectrometry. Minimal inhibitory concentrations (MIC) of the quinic acid derivative against Aeromonas hydrophila, Bacillus subtilis, Staphylococcus aureus and the fungus Aspergillus ochraceus were 250, 1000, 1000 and > 568 microg/mL, respectively.

Antibacterial activity of plant extracts from Brazilian southeast region.

A screening was conducted with 26 plants collected in the Brazilian southeast region, to identify plant extracts with antibacterial properties against Aeromonas hydrophila, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus. Initially, the agar diffusion method was employed. Then, those extracts presenting activity were submitted to a broth microdilution assay to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC).