ABSTRACT
Neolentinus ponderosus y N. lepideus son dos especies de hongos saprobios que poseen uso alimenticio tradicional en comunidades de los departamentos de Huehuetenango y Totonicapán, Guatemala. La capacidad degradadora de ambas especies les confiere potencial para el estudio de la producción de cuerpos fructíferos a nivel de sustrato, por lo que en esta investigación se evaluó el crecimiento de una cepa nativa de N. ponderosus y una de N. lepideus en el medio de cultivo agar extracto de malta (EMA) a diferente pH y también se estudió la degradación de la madera de dos especies de pino (Pinus tecunumanii y P. ayacahuite) en cámaras de podredumbre durante 12 meses. El mayor diámetro de crecimiento miceliar de la cepa N. ponderosus se observó a pH 7.0, en tanto que para N. lepideus se obtuvo a pH 5.0 y 5.6. Las colonias de ambas cepas evidenciaron textura afelpada, borde regular a irregular, color blanco, con o sin pigmento difusible, olor frutal, hifas de 1.0-5.0 µm de diámetro, con clamidosporas y fíbulas. La madera de P. tecunumanii degradada por la cepa de N. ponderosus y la madera de P. ayacahuite por la cepa N. lepideus, presentaron porcentajes de pérdida de peso de 8.76 (±5.58) y 12.07 (±5.66), respectivamente y en ambos casos se alcanzó solamente el estadio temprano de degradación. Los resultados de este estudio sientan las bases para investigaciones posteriores en los que se evalúe el cultivo en troncos de ambas especies para la producción de cuerpos fructíferos con fines alimenticios y comerciales
Neolentinus ponderosus and N. lepideus are two saprophytic fungi species used traditionally in Huehuetenango and Totonicapán, Guatemala. The degradative capacity of both species confers them potential for fruiting bodies production. This study evaluated the mycelial growth of two native strains of N. ponderosus and N. lepideus in malt extract agar (EMA) at different pH and the degradation of wood from two pine species in rot chambers during 12 months. pH 7.0 was the most appropriate for the mycelial growth of N. ponderosus and for N. lepideus were 5.0 and 5.6. The colonies of both strains showed fruity odor, velvety texture, regular to irregular edge, white color, with or without diffusible pigment, hyphae with 1-5 µm width, chlamydospores and clamp connections. Wood from Pinus tecunumanii and P. ayacahuite exhibit weight-loss percentages between 8.76 ± 5.58 and 12.07 ± 5.66, with N. ponderosus 145.2003 and N. lepideus 90.2002, respectively. In both cases reached the early stage of brown-rot decay. These results could be useful for future research that evaluate the fruiting bodies production in logs for food and commercial purposes
ABSTRACT
Introduction In vitro bioassays were performed to access the larvicidal activity of crude extracts from the endophytic fungus Pestalotiopsis virgulata (Melanconiales, Amphisphaeriaceae) and the saprophytic fungus Pycnoporus sanguineus (Basidiomycetes, Polyporaceae) against the mosquitoes Aedes aegypti and Anopheles nuneztovari. Methods The extracts were tested at concentrations of 100, 200, 300, 400 and 500ppm. Ethyl acetate mycelia (EAM) extracts and liquid culture media (LCM) from Pe. virgulata and Py. sanguineus were tested against third instar larvae of Ae. aegypti and An. nuneztovari. Results The larvicidal activity of the EAM extracts from Pe. virgulata against Ae. aegypti had an LC50=101.8ppm, and the extract from the basidiomycete fungus Py. sanguineus had an LC50=156.8ppm against the Ae. aegypti larvae. The Pe. virgulata extract had an LC50=16.3ppm against the An. nuneztovari larvae, and the Py. sanguineus extract had an LC50=87.2ppm against these larvae. Conclusions These results highlight the larvicidal effect of EAM extracts from the endophyte Pe. virgulata against the two larval mosquitoes tested. Thus, Pe. virgulata and Py. sanguineus have the potential for the production of bioactive substances against larvae of these two tropical disease vectors, with An. nuneztovari being more susceptible to these extracts. .