Optimization of high pressure bioactive compounds extraction from pansies (Viola × wittrockiana) by response surface methodology

ABSTRACT

Response surface methodology (RSM) was employed for the first time to optimize high pressure extraction (HPE) conditions of bioactive compounds from pansies, namely: pressure (X₁: 0–500 MPa), time (X₂: 5–15 min) and ethanol concentration (X₃: 0–100%). Consistent fittings using second-order polynomial models were obtained for flavonoids, tannins, anthocyanins, total reducing capacity (TRC) and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity. The optimum extraction conditions based on combination responses for TRC, tannins and anthocyanins were: X₁ = 384 MPa, X₂ = 15 min and X₃ = 35% (v/v) ethanol, shortening the extraction time when compared to the classic method of stirring (approx. 24 h). When the optimum extraction conditions were applied, 65.1 mg of TRC, 42.8 mg of tannins and 56.15 mg of anthocyanins/g dried flower were obtained. Thus, HPE has shown to be a promising technique to extract bioactive compounds from pansies, by reducing the extraction time and by using green solvents (ethanol and water), for application in diverse industrial fields.

KEYWORDS:

• Pansies flowers
• high pressure extraction
• antioxidant activity
• bioactive compounds
• response surface methodology

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Luana Fernandes http://orcid.org/0000-0001-9377-2453

Susana I.P. Casal http://orcid.org/0000-0002-1686-3850

José A. Pereira http://orcid.org/0000-0002-2260-0600

Elsa Ramalhosa http://orcid.org/0000-0003-2503-9705

Jorge A. Saraiva http://orcid.org/0000-0002-5536-6056

Additional information

Funding

The authors acknowledge the Portuguese Foundation for Science and Technology (FCT, Portugal) for the financial support provided by the research grant SFRH/BD/95853/2013 and FCT/MEC for the financial support to QOPNA Research Unit (FCT UID/QUI/00062/2013) through national funds and where applicable co-financed by the FEDER, within the PT2020 Partnership Agreement, and REQUIMTE through the Project PEst/UID/QUI/50006/2013. The authors are also grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013).