Ester Risco

Biological and Nonbiological Antioxidant Activity of Some Essential Oils

Fifteen essential oils, four essential oil fractions, and three pure compounds (thymol, carvacrol, and eugenol), characterized by gas chromatography and gas chromatography-mass spectrometry, were investigated for biological and nonbiological antioxidant activity. Clove oil and eugenol showed strong DPPH (2,2-diphenyl-1-picrylhydrazyl) free-radical scavenging activity (IC50 = 13.2 μg/mL and 11.7 μg/mL, respectively) and powerfully inhibited reactive oxygen species (ROS) production in human neutrophils stimulated by PMA (phorbol 12-myristate 13-acetate) (IC50 = 7.5 μg/mL and 1.6 μg/mL) or H2O2 (IC50 = 22.6 μg/mL and 27.1 μg/mL). Nutmeg, ginger, and palmarosa oils were also highly active on this test. Essential oils from clove and ginger, as well as eugenol, carvacrol, and bornyl acetate inhibited NO (nitric oxide) production (IC50 < 50.0 μg/mL). The oils of clove, red thyme, and Spanish oregano, together with eugenol, thymol, and carvacrol showed the highest myeloperoxidase inhibitory activity. Isomers carvacrol and thymol displayed a disparate behavior in some tests. All in all, clove oil and eugenol offered the best antioxidant profile.

Effect of Some Essential Oils on Phagocytosis and Complement System Activity

The aim of the present study was to investigate the in vitro activity of 15 essential oils, 4 essential oil fractions, and 3 pure compounds (thymol, carvacrol, and eugenol) on phagocytosis by human neutrophils and on complement system. Samples were characterized by GC and GC-MS. Most of the oils (nutmeg, clove, niaouli, tea tree, bay laurel, lemon, red thyme, ginger), nutmeg terpenes, eugenol, and carvacrol showed mild to moderate inhibition of phagocytosis (25-40% inhibition at doses ranging from 40 to 60 μg/mL); highest inhibitory activity was found for thymol (72% at 56 μg/mL), whereas the mixture of bornyl and isobornyl acetates showed a mild stimulating activity (21% at 56 μg/mL). All samples were inactive in the alternative pathway of complement system, whereas on classical pathway, clove oil, eugenol, palmarosa oil, red thyme oil, tarragon oil, and carvacrol showed the highest activity, with IC50 values ranging from 65 to 78 μg/mL.

Efecto del arandano americano (Cysticlean®), sobre la adherencia de Escherichia Coli A células epiteliales de vejiga. Estudio in vitro y ex vivo

Resumen es: Objetivo: Las proantocianidinas (PACs) del arandano americano son las principales responsables de su eficacia en infecciones del tracto urinario. Su meca...

Antioxidant activity of Tween-20 and Tween-80 evaluated through different in-vitro tests.

This study aimed to evaluate the possible antioxidant activity of Tween‐20 and Tween‐80, two amphipathic nonionic surfactants commonly used as solubilizers and stabilizers, whose pharmacological effects have been ignored to a large degree.

Screening of Anticancer and Immunomodulatory Activities of Panamanian Plants

Fifty-one extracts, from six Panamanian plants species selected on the basis of their toxicities against Artemia salina, belonging to five families and five genera, were screened for their in vitro anticancer (TK-10, UACC-62, MCF-7) and immunomodulatory activities [inhibition of complement, classical (CP) and alternative (AP) complement pathway and lymphoproliferation]. The results showed that 9 (17.6%) of 51 extracts presented anticancer activity against cancer cell lines, while 28 (54.9%) of 51 extracts stimulated normal spleen cells proliferation, and 25 (49.0%) inhibited in vitro lymphoid tumor cell growth. Finally, 7 (19.4%) and 10 (27.8%) out of 36 extracts showed high and moderate anticomplementary activity on CP, respectively. Moreover, out of 36 extracts, 1 (2.8%) produced higher inhibition while 4 (11.1%) showed moderate inhibition in the alternate pathway. The dichloromethane, methanolic and aqueous extracts from the leaf (3.0, 3.2, 4.2) and branch (3.5, 5.7, 5.8) of Trichospermum galeottii and from the leaf (2.4, 2.5, 5.6) and stem (2.3, 2.3, 4.7) of Sauraria yasicae were the most active immunomodulatory plants. The dichloromethane extract from the root of Morinda panamensis (8.7, 4.4, 6.3) was active against the three cancer cell lines, while the dichloromethane extract from the bark of Trichospermum galeottii(TK-10 = 3.4,UACC-62 = 9.4) and the bark of Morinda panamensis (UACC-62 = 5.5, MCF-7 = 5.9) as well as the methanolic extract from the root of Morinda rojoc (UACC-62 = 9.2, MCF-7 = 9.4) exhibited selectivity against two cancer cell lines.