Validation of an analytical method by HPLC for the quantification of yangambin from the Ocotea duckei species / Validación de un método analítico por HPLC para la cuantificación de yangambin de la especie Ocotea duckei

Ocotea duckei , known as Louro - de - cheiro, belongs to the Lauraceae family and presents lignoid yangambine (YAN) as the main plant marker. This work aimed to develop and validate an analytical method by high performance liquid chromatography for the quantification of YAN. The sample used was the crude eth anolic extract (CEE) obtained from aerial parts. In the developed method, a C18 column was used. The mobile phase was composed of acetonitrile and water (45:55), whereas the method parameters included mobile phase flow rate at 0.8 mL/min, oven temperature at 40°C, and monitoring at 205 nm. In the validation, the parameters of selectivity, linearity, precision, accuracy, robustness, limits of detection and quantification were evaluated. As a result, the developed method is in accordance with the guidelines f or validation of analytical methods and presented satisfactory chromatographic parameters for YAN determination. Thus, the present analytical methodology can be applied in the quality control of O. duckei raw materials.

Ocotea duckei , conocida como Louro - de - cheiro, pertenece a la familia Lauraceae y presenta la yangambina lignoide (YAN) como principal marcador vegetal. Este trabajo tuvo como objetivo desarrollar y val idar un método analítico por cromatografía líquida de alta resolución para la cuantificación de YAN. La muestra utilizada fue el extracto etanólico crudo (EEC) obtenido de partes aéreas. En el método desarrollado se utilizó una columna C18. La fase móvil c onsistió en acetonitrilo y agua (45:55), mientras los parámetros del método incluyeron el caudal de la fase móvil a 0,8 m L /min, la temperatura del horno a 40°C y la monitorización a 205 nm. En la validación se evaluaron los parámetros de selectividad, line alidad, precisión, exactitud, robustez, límites de detección y cuantificación. Como resultado, el método desarrollado está de acuerdo con las pautas para la validación de métodos analíticos y presentó parámetros cromatográficos satisfactorios para la deter minación de YAN. Por lo tanto, la presente metodología analítica se puede aplicar en el control de calidad de las materias primas de O. duckei.

In vitro anti-Candida activity and mechanism of action of the flavonoid isolated from Praxelis clematidea against Candida albicans species.

The prevalence of candidiasis in the world is high. Candida species are able to create superficial and systemic infections. Candida albicans is an opportunistic pathogen, causing mycoses in immunocompromised patients as well as long-term antibiotic users. The present study objective was to evaluate in vitro anti-candida effect of this compost isolated from Praxelis clematidea. The minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) were determined by the broth microdilution techniques. We also investigated possible flavonoid 5,7,4´trimethoxflavone (TMF) action on cell walls (0.8 M sorbitol) and cell membranes (TMF to ergosterol binding). The MIC50 of flavonoid were 64 𝜇g/mL and tha MFC50 was 64 𝜇g/mL. Involvement with the cell wall and ergosterol binding were comproved as possible mechanisms of action. In conclusion the flavonoid showed in vitro antifungal potential against strains of C. albicans.

Antifungal Effect of Flavonoid 5, 7, 4’- Trimethoxyflavone against Candida krusei Strains.

Most of the flavonoids are considered as constitutive antimicrobial ingredients, especially those belonging to prenylated flavonoids, flavones and isoflavones. In the study, the flavonoid 5,7,4’- trimethoxyflavone was evaluated for its antifungal effects. Four fungal strains were used in the study for activities, Candida krusei – LM 9700, Candida krusei – LM 656, Candida krusei– LM 13 and Candida krusei – LM08. All the microorganism strains were obtained from the Laboratory of Mycology collection. Microdilution method was used for antifungal assay of the flavonoid. The results were also compared with the standard drug, Nistatin (100 UI/mL). The obtained results showed activity fungistatic against Candida krusei strains.