Arbolado urbano de la zona metropolitana de Asunción (Paraguay) y hongos descomponedores asociados

La madera puede presentar una riqueza de organismos que puedan asociarse a la pudrición, específicamente organismos fúngicos del Phylum Basidiomycota. Este trabajo tuvo la finalidad de identificar cuáles son los principales géneros de hongos descomponedores de la madera que afectan a las diversas especies forestales en el Área Metropolitana de Asunción, en los lugares: Paseo Central de la Avenida Mariscal López, el Parque Carlos Antonio López, las Plazas de Las Américas, Infante Rivarola, Plaza Italia y Uruguaya, de la ciudad de Asunción, Paraguay, teniendo en cuenta la diversidad arbórea urbana. Se realizó un inventario forestal procediendo a la identificación de los árboles que se encuentran en el área de estudio. Se realizó la colecta y caracterización histológica de los hongos que afectan a los árboles inventariados para que fueran identificados a nivel de género. Las especies forestales de mayor abundancia registradas fueron las pertenecientes a la familia Fabaceae. Las especies de hongos descomponedores de la madera encontrados son: Ganoderma australe, Ganoderma sp., Fomitiporia sp. y Hydnopolyporus fimbriatus.

Bioprospecting of the agaricomycete Ganoderma australe GPC191 as novel source for l-asparaginase production

Abstractl-Asparaginase is a therapeutically and industrially-competent enzyme, acting predominantly as an anti-neoplastic and anti-cancerous agent. The existing formulations of prokaryotic l-asparaginase are often toxic and contain l-glutaminase and urease residues, thereby increasing the purification steps. Production of l-glutaminase and urease free l-asparaginase is thus desired. In this research, bioprospecting of isolates from the less explored class Agaricomycetes was undertaken for l-asparaginase production. Plate assay (using phenol red and bromothymol blue dyes) was performed followed by estimation of l-asparaginase, l-glutaminase and urease activities by Nesslerization reaction for all the isolates. The isolate displaying the desired enzyme production was subjected to morphological, molecular identification, and phylogenetic analysis with statistical validation using Jukes-Cantor by Neighbour-joining tree of Maximum Likelihood statistical method. Among the isolates, Ganoderma australe GPC191 with significantly high zone index value (5.581 ± 0.045 at 120 h) and enzyme activity (1.57 ± 0.006 U/mL), devoid of l-glutaminase and urease activity was selected. The present study for the first-time reported G. australe as the potential source of l-glutaminase and urease-free l-asparaginase and also is one of the few studies contributing to the literature of G. australe in India. Hence, it can be postulated that it may find its future application in pharmaceutical and food industries.

CONHECIMENTO ETNOMICOLÓGICO DE COMUNIDADES QUE HABITAM O ENTORNO DA REBIO DE PEDRA TALHADA, ALAGOAS, BRASIL

Estudos etnomicológicos sobre comunidades brasileiras são escassos, quase todos centrados em povos da Amazônia. O presente trabalho teve por objetivo verificar a existência de conhecimento etnomicológico em nove comunidades nordestinas estabelecidas nas proximidades da Reserva Biológica de Pedra Talhada - RBPT (Quebrangulo, AL). Utilizou-se um formulário semiestruturado, um álbum de fotografias e amostras de macrofungos recém-coletadas para entrevistar 61 pessoas (59% homens; 41% mulheres, 18 a 81 anos), a maioria agricultores (70%) com baixo nível de instrução. Quase todos (92%) reconheceram os macrofungos e a maioria citou seus nomes populares, baseados em caracteres morfológicos, associados ao ambiente onde ocorrem (cebola da mata, cogumelo do cocô, orelha de pau) ou às propriedades a eles atribuídas (cogumelo do bem e cogumelo do mal). Percebem a relação desses organismos com o ambiente e a influência dos fatores climáticos sobre sua esporulação. Chás preparados com basidiomicetos foram indicados para tratamento de câncer (Fomes fasciatus) e asma (Ganoderma australe); duas espécies não identificadas foram indicadas para tratamento de problemas respiratórios. Cookeina tricholoma (Ascomycota) foi referida como comestível por um ex-caçador idoso. O uso lúdico foi relatado para uma espécie de Geastrum (Basidiomycota). Embora não micófilos, os entrevistados percebem os macrofungos como elementos importantes no ambiente. PALAVRAS-CHAVE: Etnobiologia. Etnomicologia. Macrofungos. Mata Atlântica. Micologia.

An Integrated In Silico and In Vitro Assays of Dipeptidyl Peptidase-4 and α-Glucosidase Inhibition by Stellasterol from Ganoderma australe

Background: Ganoderma fungus is rich in terpenoids. These compounds are known for their anti-hyperglycemic activities. However, the study of terpenoids as the secondary metabolite from Ganoderma as a dipeptidyl peptidase-4 (DPP-4) inhibitor remains unexplored. In addition, we examined the α-glucosidase inhibition activity. Objective: This study aimed to isolate the major terpenoid from non-laccate Ganoderma and examined its inhibitor activity on DPP-4 and α-glucosidase enzymes, and its interaction. Methods: The compound was isolated using column chromatography from Ganoderma australe. The structure of the isolated compound was confirmed by 1H and 13C nuclear magnetic resonance spectroscopy, while the inhibitory activity was evaluated using an enzymatic assay. The interaction of the isolated compound with DPP-4 and α-glucosidase enzymes was investigated using an in silico study. Results: The isolated compound was identified as stellasterol; IC50 values for DPP-4 and α-glucosidase inhibitor were 427.39 µM and 314.54 µM, respectively. This study revealed that the inhibitory effect of stellasterol on DPP-4 enzyme is through hydrophobic interaction, while the α-glucosidase enzyme is due to the interaction with six amino acids of the enzyme. Conclusion: Stellasterol is the major component of the steroid from G. australe. Enzyme inhibitory assay and in silico study suggest that stellasterol may contribute antidiabetic activity with a mechanism closer to acarbose rather than to sitagliptin.