Open Access

Balanites aegyptiaca (Balanitaceae) is a widely grown desert plant with multiuse potential. In the present paper, a crude extract from B. aegyptiaca seeds equivalent to a ratio of 1 : 2000 seeds to the extract was screened for antiplasmodial activity. The determined IC(50) value for the chloroquine-susceptible Plasmodium falciparum NF54 strain was 68.26 μg/μL ± 3.5. Analysis of the extract by gas chromatography-mass spectrometry detected 6-phenyl-2(H)-1,2,4-triazin-5-one oxime, an inhibitor of the parasitic M18 Aspartyl Aminopeptidase as one of the compounds which is responsible for the in vitro antiplasmodial activity. The crude plant extract had a K(i) of 2.35 μg/μL and showed a dose-dependent response. After depletion of the compound, a significantly lower inhibition was determined with a K(i) of 4.8 μg/μL. Moreover, two phenolic compounds, that is, 2,6-di-tert-butyl-phenol and 2,4-di-tert-butyl-phenol, with determined IC(50) values of 50.29 μM ± 3 and 47.82 μM ± 2.5, respectively, were detected. These compounds may contribute to the in vitro antimalarial activity due to their antioxidative properties. In an in vivo experiment, treatment of BALB/c mice with the aqueous Balanite extract did not lead to eradication of the parasites, although a reduced parasitemia at day 12 p.i. was observed.

The non-filarial and non-communicable disease podoconiosis affects around 4 million people and is characterized by severe leg lymphedema accompanied with painful intermittent acute inflammatory episodes, called acute dermatolymphangioadenitis (ADLA) attacks. Risk factors have been associated with the disease but the mechanisms of pathophysiology remain uncertain. Lymphedema can lead to skin lesions, which can serve as entry points for bacteria that may cause ADLA attacks leading to progression of the lymphedema. However, the microbiome of the skin of affected legs from podoconiosis individuals remains unclear. Thus, we analysed the skin microbiome of podoconiosis legs using next generation sequencing. We revealed a positive correlation between increasing lymphedema severity and non-commensal anaerobic bacteria, especially Anaerococcus provencensis, as well as a negative correlation with the presence of Corynebacterium, a constituent of normal skin flora. Disease symptoms were generally linked to higher microbial diversity and richness, which deviated from the normal composition of the skin. These findings show an association of distinct bacterial taxa with lymphedema stages, highlighting the important role of bacteria for the pathogenesis of podoconiosis and might enable a selection of better treatment regimens to manage ADLA attacks and disease progression.

Understanding the interactions between the cervico-vaginal microbiome, immune responses, and sexually transmitted infections (STIs) is crucial for developing targeted diagnostic and therapeutic strategies. Although microbiome analyses are not yet standard practice, integrating them into routine diagnostics could enhance personalized medicine and therapies. We investigated the extent to which partial 16S short-read amplicon microbiome analyses could inform on the presence of six commonly encountered STI-causing pathogens in a patient cohort referred for colposcopy, and whether relevant taxonomic or diagnostic discrepancies occur when using vaginal rather than cervical swabs. The study cohort included cervical and vaginal samples collected from women referred for colposcopy at the University Hospital Bonn between November 2021 and February 2022, due to an abnormal PAP smear or positive hrHPV results. 16S rRNA gene sequencing libraries were prepared targeting the V1–V2 and V4 regions of the 16S RNA gene and sequenced on the Illumina MiSeq. PCR diagnostics for common STI-causing pathogens were conducted using the Allplex STI Essential Assay Kit (Seegene, Seoul, Republic of Korea). Concerning the bacterial microbiome, no significant differences were found between vaginal and cervical samples in terms of prevalence of taxa present or diversity. A total of 95 patients and 171 samples tested positive for at least one among Ureaplasma parvum, Ureaplasma urealyticum, Mycoplasma hominis, Mycoplasma genitalium, Chlamydophila trachomatis or Neisseria gonorrhoeae. Sequencing the V1–V2 region enabled detection of one-third to half of the PCR-positive samples, with the detection likelihood increasing at lower cycle threshold (Ct) values. In contrast, sequencing the V4 region was less effective overall, yielding fewer species-level identifications and a higher proportion of undetermined taxa. We demonstrate that the vaginal microbiome closely mirrors the cervical microbiome, a relationship that has not been explored previously, but which broadens the possibilities for microbiome analysis and pathogen detection and establishes vaginal swabs as a reliable method for detecting the investigated pathogens, with sensitivities comparable with or superior to endocervical swabs. On the other hand, the sensitivity of partial 16S amplicon sequencing appears insufficient for effective STI diagnostics, as it fails to reliably identify or even detect pathogens at higher Ct values.