Crude extracts and eight isolated compounds from Chresta scapigera were evaluated for antibacterial and antifungal activities by the agar-well diffusion method. Twenty strains, including Gram-positive and Gramnegative bacteria and yeasts were used in the bioassay. Hexane extracts presented the best results while ethanol extracts did not indicate inhibition of the microbial growth. Amongst the evaluated compounds β-amyrin acetate, tiliroside and luteolin showed the strongest antimicrobial effect.

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A comparative study of classical and ultrasound-assisted extractions of steroids and triterpenoids from stem, leaves and flowers of Chresta exsucca, C. scapigera and C. sphaerocephala is described. The direct analysis of crude apolar and medium-polar extracts has been conducted by high-resolution gas chromatography followed by co-injections of the crude extract with certified standards on capillary columns of different polarities. The use of ultrasound decreased significantly the total time of treatment and in addition, this extraction method was more effective for the steroids and most of the triterpenes.

Fractionation of bioactive crude extracts of Chresta scapigera led to the isolation of four triterpenes and five flavonoids, among them β-amyrin acetate (1), 11α,12α-oxidetaraxeryl acetate (2) and lupeol (3), as well as the flavonoids apigenin (6), kaempferol (7), crysoeriol (8) and luteolin (9) were active against Leishmania amazonensis amastigotes-like stages, while only the flavonoids (6), (7) and (9) showed toxicity towards bloods trypomastigote forms of Trypanosoma cruzi.