Antibacterial and Cytotoxic Activities of Capparis zeylanica Linn Roots

Se analizaron extractos crudos y un ácido graso, ácido octadec-7-en-5-ynoic (1), de la corteza de la raíz de Capparis zeylanica Linn. (familia de las Capparidaceae) para observar sus actividades antibacterianas frente a la bacteria Gram positiva y Gram negativa. Entre los extractos crudos, el extracto de cloroformo mostró una buena actividad frente a todos los organismos de prueba. El ácido graso (1) aislado del extracto de cloroformo mostró actividades antibacterianas frente a todos los organismos de prueba, a excepción de E. coli. Las actividades se compararon con un antibiótico estándar: la kanamicina. Las concentraciones inhibitorias mínimas (CIH) de 1, determinadas mediante la técnica de dilución en serie, fueron 64 μg/ml frente a Bacillus subtilis y Shigella dysenteriae. Las actividades citotóxicas del extracto crudo y del ácido graso (1) se observaron mediante el bioensayo de gambas en salmuera y el valor de LC50 del compuesto fue 6,27 μg/mlCrude extracts and a fatty acid, octadec-7-en-5-ynoic acid (1), from the root bark of Capparis zeylanica Linn. (Fam. Capparidaceae) were screened for their antibacterial activities against Gram positive and Gram negative bacteria. Among the crude extracts, chloroform extract showed good activity against all test organisms. The fatty acid (1) isolated from chloroform extract exhibited antibacterial activities against test organisms except E. coli. The activities were compared to a standard antibiotic- kanamycin. The minimum inhibitory concentrations (MICs) of 1, determined by serial dilution technique, were found to be 64 μg/ml against Bacillus subtilis and Shigella dysenteriae. The cytotoxic activities of crude extract and fatty acid (1) were observed by brine shrimp biassay and LC50 value of the compound was found to be 6.27 μg/m

Differential Anti-Proliferative and Anti-Migratory Activities of Ursolic Acid, 3-O-Acetylursolic Acid and Their Combination Treatments with Quercetin on Melanoma Cells

We evaluate how 3-acetylation modulates the in vitro activity of ursolic acid in melanoma cells alone or in combination treatments with quercetin. Anti-proliferative studies on A375 cells and adult human dermal fibroblasts included analyses on cell cycle distribution, caspase activity, phosphatidylserine translocation, cell morphology and Bax/Bcl-2 protein expression. Then, 2D and 3D migration of B16F10 cells were studied using scratch and Transwell assays, respectively. Ursolic acid and 3-O-acetylursolic acid have shown similar GI50 on A375 cells (26 µM vs. 32 µM, respectively) significantly increased both early and late apoptotic populations, activated caspases 3/7 (48–72 h), and enhanced Bax whilst attenuating Bcl-2 expression. Ursolic acid caused elevation of the sub-G1 population whilst its 3-acetyl derivative arrested cell cycle at S phase and induced strong morphological changes. Combination treatments showed that ursolic acid and quercetin act synergistically in migration assays but not against cell proliferation. In summary, 3-O-acetylursolic acid maintains the potency and overall apoptotic mechanism of the parent molecule with a more aggressive influence on the morphology of A375 melanoma cells but the 3-acetylation suppresses its anti-migratory properties. We also found that ursolic acid can act in synergy with quercetin to reduce cell migration.</jats:p

Antimicrobial activities of alkaloids and lignans from zanthoxylum budrunga

This paper examines the antimicrobial activities of alkaloids and lignans from zanthoxylum budrunga

Microbial efflux systems and inhibitors: Approaches to drug discovery and the challenge of clinical implementation

Conventional antimicrobials are increasingly ineffective due to the emergence of multidrug-resistance among pathogenic microorganisms. The need to overcome these deficiencies has triggered exploration for novel and unconventional approaches to controlling microbial infections. Multidrug efflux systems (MES) have been a profound obstacle in the successful deployment of antimicrobials. The discovery of small molecule efflux system blockers has been an active and rapidly expanding research discipline. A major theme in this platform involves efflux pump inhibitors (EPIs) from natural sources. The discovery methodologies and the available number of natural EPI-chemotypes are increasing. Advances in our understanding of microbial physiology have shed light on a series of pathways and phenotypes where the role of efflux systems is pivotal. Complementing existing antimicrobial discovery platforms such as photodynamic therapy (PDT) with efflux inhibition is a subject under investigation. This core information is a stepping stone in the challenge of highlighting an effective drug development path for EPIs since the puzzle of clinical implementation remains unsolved. This review summarizes advances in the path of EPI discovery, discusses potential avenues of EPI implementation and development, and underlines the need for highly informative and comprehensive translational approaches. © Kourtesi et al

Antibacterial and antifungal activities of the constituents of flemingia paniculata

A salicylic acid derivative (1), a cinnamaldehyde (2), and six isoflavones (3-8) from the stem bark of Flemingia paniculata. Wall. (Leguminosae) were tested for antibacterial (both Gram-positive and Gram-negative) and antifungal activities. All the compounds showed significant activities against the test organisms having MIC values in the range of 1.57-200 μ g/mL. The highest potency (MIC = 1.57 μ g/mL) was exhibited by 3 against Staphylococcus aureus