Annona Genus: Traditional Uses, Phytochemistry and Biological Activities.

Species from the Annona (Anonaceae) genus are used in traditional medicine for the treatment of various diseases. Ethnobotanical studies provide information regarding the plant part and the preparation method being used, while scientific studies such as in vitro, in vivo, and clinical tests can provide evidence supporting ethnopharmacological reports, directing studies towards the isolation of compounds which may be active for specific pathologies. Annona muricata and Annona squamosa were the most commonly reported species from those studied, with Annona cherimola and Annona classiflora also standing out. Acetogenins were the most commonly isolated metabolite class due to their cytotoxic properties, with flavonoids, alkaloids, steroids, and peptides also being reported. Many species from the Annona genus have proven biological activities, such as antitumor, antioxidant, antimicrobial and antifungal. The present review had as its objective to facilitate access to ethnobotanical, chemical and biological information in order to direct future researches.

Antibiotic-Potentiating Activity of Phanostenine Isolated from Cissampelos sympodialis Eichler.

Cissampelos sympodialis Eichler is well studied and investigated for its antiasthmatic properties, but there are no data in the literature describing antibacterial properties of alkaloids isolated from this botanical species. This work reports the isolation and characterization of phanostenine obtained from roots of C. sympodialis and describes for the first time its antimicrobial and antibiotic modulatory properties. Phanostenine was first isolated from Cissampelos sympodialis and its antibacterial activities were determined. Chemical structures of the alkaloid isolate were determined using spectroscopic and chemical analyses. Phanostenine was also tested for its antibacterial activity against standard strains and clinical isolates of Escherichia coli and Staphylococcus aureus. Minimal inhibitory concentration (MIC) was determined in a microdilution assay and for the evaluation of antibiotic resistance-modifying activity. MIC of the antibiotics was determined in the presence or absence of phanostenine at sub-inhibitory concentrations. The evaluation of antibacterial activity by microdilution assay showed activity for all strains with better values against S. aureus ATCC 12692 and E. coli 27 (787.69 mm). The evaluation of aminoglycoside antibiotic resistance-modifying activity showed reduction in the MIC of the aminoglycosides (amikacin, gentamicin and neomycin) when associated with phanostenine, MIC reduction of antibiotics ranging from 21 % to 80 %. The data demonstrated that phanostenine possesses a relevant ability to modify the antibiotic activity in vitro. We can suggest that phanostenine presents itself as a promising tool as an adjuvant for novel antibiotics formulations against bacterial resistance.