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The surge in multidrug-resistant pathogens worldwide has jeopardized the clinical efficiency of many current antibiotics. This problem steered many researchers in their quest to discover new effective antimicrobial agents from natural origins including plants or their residing endophytes. In this work, we aimed to identify the endophytic fungi derived from Hedera helixL. and investigate their potential antimicrobial activity. Bioguided fractionation approach was conducted to isolate the pure compounds from the most active fungal fraction. Out of a total of six different isolated endophytic fungal strains, only Aspergillus cejpiishowed the highest activity against all tested microbial strains. The most active fraction was the dichloromethane/methanol fraction (DCM:MeOH), where it showed significant activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Serratia marcescens, Acinetobacter baumannii, Salmonella typhi, and three drug-resistant clinical isolate strains including Methicillin-resistant Staphylococcus aureus(MRSA, H1), Pseudomonas aeruginosa(PS 16), and Acinetobacter baumannii(ACT 322) using tetracyline and kanamycin as the control antibiotics. Bioguided fractionation of the active fraction led to the isolation of the γ-butenolide, spiculisporic acid. Structure elucidation was carried out using 1H and 13C-NMR spectroscopic analysis. The compound showed good antimicrobial activities with minimum inhibitory concentration (MIC) values ranging from 3.9 to 31.25 μg/mL against all tested strains. Gas chromatography coupled to mass spectrometry (GC-MS) profiling was also carried out to identify the metabolites in the microbial crude extract. In conclusion, endophytic fungi, Aspergillus cejpii, isolated from Hedera helixL. roots showed promising antimicrobial activity which merits further in-depth investigations for potential utilization as a source of new antibiotics in the future. It can also be considered as a novel source for spiculisporic acid.

Twelve pairs of SSR markers were used to evaluate the genetic diversity of 138 accessions of potato cultivars from the Western Highlands region of Cameroon. The average Polymorphism information content (PIC) value (0.74) and number of alleles (7.08) indicated a high genetic diversity of the potato cultivars tested. Analysis of molecular variance revealed that most of the genetic variations are found within geographic region (≥ 91%), resulting in high gene flow (Nm > 4 individuals). Local varieties had significantly more alleles than exotic varieties. Genetic diversity estimates for accessions from low elevations were significantly lower than those from medium and high elevations. Cluster analysis showed three clusters; the model-based approach inferred two gene pools. Genotypes revealed a high level of admixture between gene pools within locations and elevations. A core collection identified in this study composed of 27 individuals representing 19.57% of the whole collection and captured 99.15% of the total alleles found. Se usaron doce pares de marcadores SSR para evaluar la diversidad genética de 138 accesiones de variedades de papa de la región de los altiplanos occidentales de Camerún. El valor promedio del contenido de la información polimórfica (PIC) (0.74) y el número de alelos (7.08) indicaron una alta diversidad genética de las variedades de papa probadas. El análisis de la varianza molecular reveló que la mayoría de las variaciones genéticas se encuentran dentro de la región geográfica (≥90%), resultando en un alto flujo genético (Nm > 4 individuos). Las variedades locales tuvieron significativamente más alelos que las exóticas. Las estimaciones de la diversidad genética para las accesiones de poca elevación fueron significativamente más bajas que las de elevaciones medias y altas. El análisis de conjunto mostró tres grupos; el enfoque basado en el modelo infirió dos grupos de genes. Los genotipos revelaron un alto nivel de mezclas entre los grupos de genes dentro de las localidades y elevaciones. Una colección núcleo identificada en este estudio se conformó de 27 individuos representando 19.57% de toda la colección y capturó 99.15% del total de alelos encontrados.