Evaluation of anticandidal and antioxidant activities of phenolic compounds from Pyrostegia venusta (Ker Gawl.) Miers

• This is the first time that verbascoside and isoverbascoside were isolated from P. venusta.
• The anticandidal activity of the verbascoside isolated from P. venusta was validated.
• P. venusta phytocomplex is more effective than the reference antimicrobials.

We have investigated the in vitro anticandidal and antioxidant activities of phenolic compounds from Pyrostegia venusta flower extracts. We used the HPLC technique to purify the flavonoid (quercetin-3-O-α-l-rhamnopyranosyl-(1→6)-β-d-galactopyranoside) and two phenylpropanoid glycosides (verbascoside and isoverbascoside); we evaluated the antimicrobial activity of the extracts against Candida strains (Candidaalbicans; Candidakrusei ATCC 6258; and the clinical isolate strains of Candida sp. C. albicans, C. krusei, Candidatropicalis, Candidaparapsilosis, and Candidaguilhermondii). The P. venusta flower extracts displayed antimicrobial and antioxidant activities. The semi-purified fraction of the P. venusta flower extract and the phenylpropanoid glycoside verbascoside exhibited activity similar to that of amphotericin B, which denoted that they are potentially applicable as natural antioxidant and anticandidal agents in the pharmaceutical industries.