Bioremediation of polycyclic aromatic hydrocarbon-contaminated saline-alkaline soils of the former Lake Texcoco.

Polycyclic aromatic hydrocarbons (PAHs) such as phenanthrene, anthracene and Benzo[a]pyrene (BaP) are toxic for the environment. Removing these components from soil is difficult as they are resistant to degradation and more so in soils with high pH and large salt concentrations as in soil of the former lake Texcoco, but stimulating soil micro-organisms growth by adding nutrients might accelerate soil restoration. Soil of Texcoco and an agricultural Acolman soil, which served as a control, were spiked with phenanthrene, anthracene and BaP, added with or without biosolid or inorganic fertilizer (N, P), and dynamics of PAHs, N and P were monitored in a 112-day incubation. Concentrations of phenanthrene did not change significantly in sterilized Acolman soil, but decreased 2-times in unsterilized soil and >25-times in soil amended with biosolid and NP. The concentration of phenanthrene in unsterilized soil of Texcoco was 1.3-times lower compared to the sterilized soil, 1.7-times in soil amended with NP and 2.9-times in soil amended with biosolid. In unsterilized Acolman soil, degradation of BaP was faster in soil amended with biosolid than in unamended soil and soil amended with NP. In unsterilized soil of Texcoco, degradation of BaP was similar in soil amended with biosolid and NP but faster than in the unamended soil. It was found that application of biosolid and NP increased degradation of phenanthrene, anthracene and BaP, but to a different degree in alkaline-saline soil of Texcoco compared to an agricultural Acolman soil.

Productos naturales con actividad antimicótica / Natural products with antimycotic activity

En las últimas décadas se ha observado no sólo un notable aumento de las infecciones causadas por hongos en todo el mundo sino un incremento de la resistencia farmacológica que han mostrado varias especies de hongos a los diferentes antimicóticos que se utilizan en la práctica médica. Esta situación ha llevado a la búsqueda de nuevos antifúngicos de origen natural. En recursos naturales, como plantas, insectos y organismos marinos y terrestres, se han identificado una serie de moléculas con actividad contra diferentes géneros y especies de hongos de importancia clínica para los humanos, convirtiéndose en alternativa para el desarrollo y la formulación de nuevos fármacos antimicóticos con menores efectos secundarios, mayor espectro de acción y menor costo que los disponibles actualmente para el tratamiento de las infecciones por hongos. En este artículo se presenta una revisión de las principales fuentes naturales de moléculas con actividad antimicótica (AU)

In the past few decades, a worldwide increase in the incidence of fungal infections has been observed and the resistance of some species of fungus to different fungicidals used in medical practice has also risen. This has led to the search for new antimycotics, particularly those obtained from natural sources such as plants, insects, and land and marine microorganisms. In these natural sources, a series of molecules with antifungal activity against different species of fungus of great clinical importance for humans has been found, and these substances have become an alternative for the development and formulation of new antifungals with fewer side effects, a greater spectrum of action and lower cost than those in current use. In this article, we review the main sources of molecules with antimycotic activity obtained from natural sources (AU)

[Natural products with antimycotic activity]. / Productos naturales con actividad antimicótica.

In the past few decades, a worldwide increase in the incidence of fungal infections has been observed and the resistance of some species of fungus to different fungicidals used in medical practice has also risen. This has led to the search for new antimycotics, particularly those obtained from natural sources such as plants, insects, and land and marine microorganisms. In these natural sources, a series of molecules with antifungal activity against different species of fungus of great clinical importance for humans has been found, and these substances have become an alternative for the development and formulation of new antifungals with fewer side effects, a greater spectrum of action and lower cost than those in current use. In this article, we review the main sources of molecules with antimycotic activity obtained from natural sources.

Cytotoxic and antiviral activities of Colombian medicinal plant extracts of the Euphorbia genus.

Forty-seven plant extracts of 10 species of the genus Euphorbia (Euphorbiaceae) used by Colombian traditional healers for the treatment of ulcers, cancers, tumors, warts, and other diseases, were tested in vitro for their potential antitumour (antiproliferative and cytotoxic) and antiherpetic activity. To evaluate the capacity of the extracts to inhibit the lytic activity of herpes simplex virus type 2 (HSV-2) and the reduction of viability of infected or uninfected cell cultures, the end-point titration technique (EPTT) and the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] colorimetric assay were used, respectively. The therapeutic index of the positive extracts for the antiviral activity was determined by calculating the ratio CC50 (50% cytotoxic concentration) over IC50 (50% inhibitory concentration of the viral effect). Five of the 47 extracts (11%) representing 3 out of 10 Euphorbia species (30%) exhibited antiherpetic action; the highest activity was found in the leaf/stem water-methanol extracts from E. cotinifolia and E. tirucalli. The therapeutic indexes of these two plant species were > 7.1; these extracts exhibited no cytotoxicity. Six extracts (13%) representing 4 plant species (40%) showed cytotoxic activity. The highest cytotoxicity was found in the dichloromethane extract obtained from E. cotinifolia leaves and the CC50 values for the most susceptible cell lines, HEp-2 and CHO, were 35.1 and 18.1 microgram/ml, respectively.

Cytotoxic and Antiviral Activities of Colombian Medicinal Plant Extracts of the Euphorbia genus

Forty-seven plant extracts of 10 species of the genus Euphorbia (Euphorbiaceae) used by Colombian traditional healers for the treatment of ulcers, cancers, tumors, warts, and other diseases, were tested in vitro for their potential antitumour (antiproliferative and cytotoxic) and antiherpetic activity. To evaluate the capacity of the extracts to inhibit the lytic activity of herpes simplex virus type 2 (HSV-2) and the reduction of viability of infected or uninfected cell cultures, the end-point titration technique (EPTT) and the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] colorimetric assay were used, respectively. The therapeutic index of the positive extracts for the antiviral activity was determined by calculating the ratio CC50 (50 percent cytotoxic concentration) over IC50 (50 percent inhibitory concentration of the viral effect). Five of the 47 extracts (11 percent) representing 3 out of 10 Euphorbia species (30 percent) exhibited antiherpetic action; the highest activity was found in the leaf/stem water-methanol extracts from E. cotinifolia and E. tirucalli. The therapeutic indexes of these two plant species were > 7.1; these extracts exhibited no cytotoxicity. Six extracts (13 percent) representing 4 plant species (40 percent) showed cytotoxic activity. The highest cytotoxicity was found in the dichloromethane extract obtained from E. cotinifolia leaves and the CC50 values for the most susceptible cell lines, HEp-2 and CHO, were 35.1 and 18.1 æg/ml, respectively

Antitumor and Antiviral Activity of Colombian Medicinal Plant Extracts

Extracts of nine species of plants traditionally used in Colombia for the treatment of a variety of diseases were tested in vitro for their potential antitumor (cytotoxicity) and antiherpetic activity. MTT (Tetrazolium blue) and Neutral Red colorimetric assays were used to evaluate the reduction of viability of cell cultures in presence and absence of the extracts. MTT was also used to evaluate the effects of the extracts on the lytic activity of herpes simplex virus type 2 (HSV-2). The 50 percent cytotoxic concentration (CC50) and the 50 percent inhibitory concentration of the viral effect (EC50) for each extract were calculated by linear regression analysis. Extracts from Annona muricata, A. cherimolia and Rollinia membranacea, known for their cytotoxicity were used as positive controls. Likewise, acyclovir and heparin were used as positive controls of antiherpetic activity. Methanolic extract from Annona sp. on HEp-2 cells presented a CC50 value at 72 hr of 49.6x103mg/ml. Neither of the other extracts examined showed a significant cytotoxicity. The aqueous extract from Beta vulgaris, the ethanol extract from Callisia grasilis and the methanol extract Annona sp. showed some antiherpetic activity with acceptable therapeutic indexes (the ratio of CC50 to EC50). These species are good candidates for further activity-monitored fractionation to identify active principles