Ultrasound-assisted extraction, optimisation using response surface methodology and HPLC-DAD phenolic compounds quantification from Passiflora edulis S. peels cultivated in Tunisia

Abstract

A new ultrasound-assisted extraction method was developed for the determination of phenolic compounds extracted from Passiflora edulis Sims peels cultivated in Tunisia. Several extraction variables including: extraction time, temperature, liquid/solid ratio and pH have been studied using response surface methodology. The extraction efficiency was evaluated by measuring the total phenolics; flavonoids and antioxidants content. The highest values of the studied response were observed after 9.78 min at 49.64 °C in a liquid-to-solid ratio 22.07 ml/g and in pH (5.54). The individual phenolic compounds content of the optimum extract peels of the Passiflora edulis Sims have been analysed using HPLC-DAD. The results revealed the presence of gallic followed by caffeic acids, while the apigenin-7-glucoside and rutin have been quantified as the abundant flavonoid compounds (0.653 and 0.488 mg/ml, respectively). This green procedure should be a promising option to guide industrial design for the production of phenolic-rich plant extracts.

ABSTRACT

Keywords:

• Passiflora edulis
• ultrasound
• response surface methodology
• Phenolic compounds
• Ultrasound-assisted extraction

Acknowledgements

We thank the Ministry of Higher Education and Scientific Research, Tunisia for their financial and Professor Mohamed Rigane for useful discussions about the English.

Disclosure statement

The authors report that they have no conflict of interests.

Data availability statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.