CARACTÉRISATION HYDROCHIMIQUE SAISONNIÈRE (ÉTIAGE ET CRUE) ET VULNÉRABILITÉ ENVIRONNEMENTALE DE LA RESSOURCE EN EAU DE LA RETENUE DE MOKOLO (EXTRÊME-NORD CAMEROUN)

The contribution of this work is a hydrochemical characterization andstudy of the environmental vulnerability of the water resources of the waterretention of Mokolo in the Far North of Cameroon, built in 1979 bydamming the upstream part of the Mayo-Tsanaga, and which is used tosupply drinking water for a population of about 800,000 inhabitants. Extremeanthropogenic pressures during the period of low water make vulnerableresource towards the pollution while the wet season rainfall result insignificant changes in the mineralization of the water due to leaching fromagricultural land in the watershed. The analysis of the results shows avariation during low water and flood water of the hydrochemical faciesconsidering a diverse origin of acquisition of the mineralization factors. Inaddition, high concentrations of certain ions during flood highlight the extentof human agricultural activities on physicochemical quality of waterresources

Heptacyclosordarianone, a New Polyketide From Sordaria sp., an Endophytic Fungus From Garcinia polyantha

Tankeu VFT, Sema DK, Jouda J-B, et al. Heptacyclosordarianone, a New Polyketide From Sordaria sp., an Endophytic Fungus From Garcinia polyantha. Natural Product Communications. 2020;15(11): 1934578X20977622.One new polyketide derivative, heptacyclosordarianone (1), together with 2 known compounds, heptacyclosordariolone (2) and sordariol (3), were isolated from an extract of Sordaria sp. AM-71, an endophytic fungus inhabiting Garcinia polyantha. The structures of these compounds were elucidated based on intensive nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry and by comparison with literature data. All compounds were assayed for their antimicrobial and cytotoxic properties. Only compound 2 showed antimicrobial activities against Bacillus subtilis DSMZ 704, Pseudomonas agarici DSMZ 11810, and Micrococcus luteus DSMZ 1605 with minimum inhibitory concentration values of 9.3, 15.5, and 16.9 mu g/mL respectively. None of the isolated compounds showed a significant cytotoxic property