Table 1.
Characteristics of the collections assayed against P. falciparum.
Fig 1.
A. Different diaphorase concentrations in the developing buffer were assayed. The absorbance was measured kinetically, taking absorbance data every two minutes verifying that the linearity of the assay comprises the 10 first minutes, time used for the development of plates. B. Percentage of hit rates depending on the dilution applied and the organism origin of the extract. Different dilutions were applied in a pilot sample of module A, comprising both actinomycetes and fungi. Extracts with ≥ 70% parasite growth inhibition were selected as hits.
Fig 2.
Examples of confirmation of the hits obtained in the primary assay.
Both the LDH and SYBR Green assays were used for the confirmation of the positive extracts of the primary screening.
Fig 3.
Compounds detected by LC-MS among the positive extracts of module A.
The known products detected are presented depending on the microorganism origin of the extract (fungi or actinomycetes). The group of underrepresented compounds comprises all the compounds that are detected in only one extract.
Fig 4.
Compounds detected in the screen.
Known (A) and unknown (B) compounds are indicated. The corresponding EC50 values, calculated using the LDH method, are shown below each compound. Results of mean and standard deviation for the EC50 values are from three independent experiments in triplicate.
Table 2.
NMR data for pepstatin K (500 MHz, CD3OD, at 24°C).
Fig 5.
Key HMBC correlations (H to C) and MS/MS fragments observed in the spectra of pepstatin K.