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Petroleum ether and dichloromethane extracts of fruits, aerial parts and exudate of Zuccagnia punctata Cav. (Fabaceae) showed moderate antifungal activities against the yeasts C. albicans, S. cerevisiae and C. neoformans (MICs: 62.5 - 250 microg/mL) and very strong antifungal activities against the dermatophytes M. gypseum, T. rubrum and T. mentagrophytes (MICs: 8 - 16 microg/mL) thus supporting the ethnopharmacological use of this plant. Antifungal activity-directed fractionation of active extracts by using bioautography led to the isolation of 2',4'-dihydroxy-3'-methoxychalcone (1) and 2',4'-dihydroxychalcone (2) as the compounds responsible for the antifungal activity. Second-order studies included MIC (80), MIC (50) and MFC of both chalcones in an extended panel of clinical isolates of the most sensitive fungi, and also comprised a series of targeted assays. They showed that the most active chalcone 2 is fungicidal rather than fungistatic, does not disrupt the fungal membranes up to 4 x MFC and does not act by inhibiting the fungal cell wall. So, 2',4'-dihydroxychalcone would act by a different mechanism of action than the antifungal drugs in current clinical use, such as amphotericin B, azoles or echinocandins, and thus appears to be very promising as a novel antifungal agent.

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Essential oils from foliage, bark and heartwood of Cryptomeria japonica D. Don from Azores Archipelago (Portugal) were analyzed by GC and GC-MS. Two populations, of black and reddish heartwood color, were studied. The main compounds found in the foliage of both populations were -pinene (9.6-29.5%), (+)-phyllocladene (3.5-26.5%), ent-kaur-16-ene (0.2-20.6%), sabinene (0.5-19.9%) and limonene (1.4-11.5%), with a large variation in individual compounds from each population. Heartwood oils were characterized by a high content of cubebol (2.8-39.9%) and epi-cubebol (4.1-26.9%) isomers, which were absent in the foliage. Elemol and eudesmol isomers were found in the foliage and heartwood oils, while (+)-phyllocladene was absent in heartwood. Black and reddish bark oils were composed of the diterpenes dehydroferruginol (1.9-5.1%) and ferruginol (2.6-11.5%), along with the sesquiterpenes -cadinene (10.4-15.9%), -muurolene (3.3-5.4%), epi-zonarene (4.0-5.0%), cubenol (9.3-14.0%), -muurolol (4.8-10.7%), -eudesmol (3.0-9.9%), eudesmol (1.9-7.0%) and hedycariol (1.4-6.2%). Azorean C. japonica oils exhibited significant chemical differences compared with native plants from Asia. The essential oils showed moderate antimicrobial activity against the pathogenic fungus Cryptococcus neoformans and human pathogenic bacteria (especially against multidrug-resistant Mycobacterium tuberculosis). The antimicrobial activity of the essential oils may be attributed to compounds such as ent-kaur-16ene, (+)-phyllocladene, ferruginol and elemol, which are present in different proportions within the complex oil mixture. These results suggest a potential use for C. japonica oils obtained from wood industry leftovers.

The methanolic crude extract from the roots of Jacquinia flammea showed moderate antifungal activity against dermatophytes and very strong antifungal activity against Colletotrichum gloeosporioides. The bioassay-guided purification of the extract, using a combination of vacuum-liquid chromatography and high performance liquid chromatography, allowed the identification of sakurasosaponin as the main metabolite responsible for the antifungal activity.

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RESUMENMediante marcadores RAPDs se determinó la variabilidad genética de aislamientos de Tricoderma spp. encontrándose alto polimorfismo con los primeros OPA 03, OPD 05, OPA 01 y OPB 01. La variación molecular observada fue baja (26%) entre las poblaciones de Trichoderma spp. identificadas por su origen geográfico como Ipiales, Pupiales y Gualmatán. En contraste la variación dentro de las poblaciones fue alta, superando el 70%. Las especies de Trichoderma spp. encontradas no mostraron una relación con el origen geográfico. Los aislados se agruparon con base en la diversidad genética de Jaccard. El rango de distancia genética entre los distintos aislamientos estuvo entre 0,37 y 1,42. La especie más frecuente fue T. harzianum que mostró alta variación al estar presente en todos los agrupamientos.Palabras clave: Diversidad genética, hongo benéfico, RAPDs. ABSTRACTThe genetic variability of Trichoderma spp isolates was determined through RAPD markers. A high polymorphism was found with primers OPB 01, OPC 01, OPA 03, OPD 05, and OPA 01. The observed molecular variation was low (26%) among populations of Trichoderma spp., identified by their geographical origin as ARTICULO DE INVESTIGACIÓN BIOLOGIA MOLECULAR REVISTA DE CIENCIAS AGRÍCOLAS