Efecto citotóxico de diterpenos derivados del ácido ent-kaureno aislados de Coespeletia moritziana (Sch. Bip. ex Wedd.) Cuatrec / Cytotoxic effect of ent-kaurene acid-derived diterpenes isolated from Coespeletia moritziana (Sch. Bip. Ex Wedd.) Cuatrec

The objective of the work was to study the cytotoxic effect of ent-kaurene acid derivatives obtained from Coespeletia moritziana (Sch. Bip. Ex Wedd.) Cuatrec., After analysis by GC/MS, IR and NMR. Isolating: kaurenic acid (I), grandifloric acid (II), 15-α-hydroxy kaurenic acid (III), 15 α-acetoxy-kaur 16-en-19-oic acid (IV), Kaurenol (V); and by hemisynthesis: 15,16-epoxy-17-acetoxy-kauran 19-oic acid (VI), 15-oxo-ent-kaur-16-en-19-oic acid (VIII), ester 2,3,4,6 -15-oxo-kaur-16-en-19-oic acid acetyl α-D-pyranosyl tetra-tetra (VII). Cytotoxicity was tested in human cancer cell lines: uterus (HeLa), lung (A-549), breast (MCF-7), African green monkey kidney non-tumor line (Vero) and human peripheral blood mononuclear cells (CMPS). Compound (I) was active against HeLa, A-549 and Vero. Compounds (II and VIII) showed moderate and good (IC50 ≤ 9 µM) cytotoxicity, respectively, against the five cell lines. Compound (V) showed moderate activity against A-549 and compound (VII), slight cytotoxicity against HeLa and A-549. Results that show the cytotoxic specificity of the isolated kaurenes and derivatives of Coespeletia moritzianaand their therapeutic potential.

El objetivo del trabajo fue estudiar el efecto citotóxico de derivados del ácido ent-kaureno obtenidos de Coespeletia moritziana (Sch. Bip. ex Wedd.) Cuatrec., previo análisis mediante GC/MS, IR y RMN. Aislandose: ácido kaurénico(I), ácido grandiflorénico (II), ácido 15-α-hidroxi kaurénico(III), ácido 15 α-acetoxi-kaur 16-en-19-oico (IV), Kaurenol (V); y por hemisíntesis: ácido 15,16-epoxi-17-acetoxi-kauran 19-oico (VI), ácido15-oxo-ent-kaur-16-en-19-oico (VIII), éster 2,3,4,6-tetra acetil α-D-piranosilo del ácido 15-oxo-kaur-16-en-19-oico (VII). La citotóxicidad fue ensayada en líneas celulares cancerosas humanas: útero (HeLa), pulmón(A-549), mama (MCF-7), línea no tumoral de riñón de mono verde africano (Vero) y células mononucleares humanas de sangre periférica (CMPS). El compuesto (I) resultó activo frente a HeLa, A-549 y Vero. Los compuestos (II y VIII), mostraron moderada y buena (IC50≤9µM) citotoxicidad respectivamente, frente a las cinco líneas celulares. El compuesto (V) presentó moderada actividad frente a A-549 y el (VII), leve citotoxicidad frente a HeLa y A-549. Resultados que evidencian la especificidad citotóxica de los kaurenos aislados y derivados de Coespeletia moritzianay su potencial terapéutico.

Chemical composition and biological activity of essential oil of achyrocline ramosissima briton ex rusby (asteraceae) / Composición química y actividad biológica del aceite esencial de achyrocline ramosissima britton ex rusby (asteraceae)

Essential oil from fresh aerial parts of Achyrocline ramosissima Britton ex Rusby (Asteraceae) collected in the Venezuelan Andes was obtained by hydrodistillation and analyzed by GC/MS. A yield of 0.10 percent w/v was afforded, and thirty seven components were identified by comparison of their retention indices (RI) and mass spectra with the Wiley GC-MS Library Data. The major components identified were rosifoliol (31.69 percent), beta-caryophyllene (8.61 percent), guaiol (3.95 percent), beta-eudesmol (3.33 percent) and selina-3,7 (11)-diene (2.99 percent). Antimicrobial activity of A. ramosissima essential oil was also evaluated against Gram positive, Gram negative bacterial strains and Candida albicans yeast. The results showed that, this oil is effective against Gram positive bacteria Staphylococcus aureus ATCC 6538 with MIC values ranging from 50 to 100 μg/mL and MBC values > 200 μg/mL as well as Bacillus subtilis CECT 39 with MIC values of 50 μg/mL and MBC of 100 μg/mL, however a low activity was observed against Gram negative bacterial strains, Pseudomonas aeruginosa AK 958, Escherichia coli CECT 99 and C. albicans yeast performing MIC and MBC values > 200 μg/mL. Cytotoxic activity was also determined against HeLa (cervix carcinoma), A-459 (lung carcinoma), MCF-7 (breast adenocarcinoma) human cancer cell lines and against normal Vero cells (African green monkey kidney), exhibiting antiproliferative effects with IC50 values of 28.2 μg/mL (HeLa cells). This is the first report regarding the chemical composition, antibacterial and cytotoxic activities of the essential oil from this species.

El aceite esencial de las partes aéreas frescas de Achyrocline ramosissima Britton ex Rusby (Asteraceae) recolectada en los Andes venezolanos fue extraído por hidrodestilación y analizado por CG/EM. Se obtuvo un rendimiento de 0,10 por ciento m/v, treinta y siete componentes fueron identificados por comparación de los índices de retención (IR) y sus espectros de masas con los datos de la biblioteca Wiley GC-MS. Los principales componentes identificados fueron rosifoliol (31,69 por ciento), beta-cariofileno (8,61 por ciento), guaiol (3,95 por ciento), beta-eudesmol (3,33 por ciento) y selina-3,7 (11)-dieno (2,99 por ciento). La actividad antimicrobiana del aceite esencial de A. ramosissima fue evaluada contra cepas bacterianas Gram positivas, Gram negativas y la levadura Candida albicans. Los resultados mostraron que el aceite esencial fue activo contra las bacterias Gram positivas Staphylococcus aureus ATCC 6538 con una CIM entre 50-100 μg/mL y CBM de valores > 200 μg/mL y Bacillus subtilis CECT 39 con CIM de 50 μg/mL y CBM de 100 μg/mL, sin embargo se observó una baja actividad contra las cepas bacterianas Gram negativas Pseudomonas aeruginosa AK 958, Escherichia coli CECT 99 y la levadura C. albicans cuyos valores de CIM y CBM fueron > 200 μg/mL. La actividad citotóxica fue determinada frente a las líneas celulares cancerígenas HeLa (carcinoma de cuello uterino), A-459 (carcinoma de pulmón), MCF-7 (adenocarcinoma de mama) y frente a las células normales Vero (células renales de mono verde), mostrando efectos antiproliferativos con valores de CI50 28.2 μg/mL frente a las células HeLa. Este es el primer reporte sobre la composición química, actividad antibacteriana y citotóxica del aceite esencial de esta especie.

Chemical composition, antimicrobial and cytotoxic activities of Piper hispidum Sw. essential oil collected in Venezuela.

This article provides an evaluation of the chemical composition, antimicrobial and cytotoxic activities of the essential oil of Piper hispidum Sw collected in the Venezuelan Andes. The chemical composition was examined by GC/MS analysis. Thirty four compounds were identified representing 95.2 % of the total oil. The major components were α-pinene (15.3 %), β-pinene (14.8 %), β-elemene (8.1 %), caryophyllene oxide (7.8 %) and δ-3-carene (6.9 %). Antimicrobial activity was observed against Gram positive bacterial strains S. aureus ATCC 6538, S. epidermides CECT232, S. saprophyticus CECT 235, B. cereus CECT496, B. subtilis CECT39 and E. faecalis CECT735 showing MIC values between 6.25 to 15 μg/mL and MBC values of 12.5 to 15 μg/mL however a low activity was observed against Gram negative bacterial strains E. coli CECT99, P. mirabilis CECT 170 and P.aeruginosa AK 958 performing MIC and MBC values of  200 μg/mL. On the other hand, Candida albicans yeast presented a moderate activity with MIC 100-200 μg/mL and MBC  200 μg/mL.Cytotoxic activity was also determined against HeLa (cervix carcinoma), A-459 (lung carcinoma), MCF-7 (breast adenocarcinoma) human cancer cell lines and against normal Vero cells (African green monkey kidney), exhibiting potent antiproliferative effects with IC50 values ranging from 18.6 to 37.7 μg/mL.