Effect of ultrasonic-assisted extraction on the properties, antioxidant and inflammatory activities of carotenoids from gac (Momordica cochinchinensis) fruit pericarp

Abstract

This study investigated the effects of ratio of ethanol to water (green solvent), extraction temperature and reaction time on properties of carotenoids ultrasonically extracted from pericarp of gac fruit. The solvent ratio and temperature significantly affected the antioxidant activity and carotenoid contents. Ultrasonic-assisted extraction (UAE) with absolute ethanol at 75°C for 15 min produced the extract with the highest antioxidant activity and carotenoid level similar to the extract extracted for 30 min. This extract consisted of lycopene, β-carotene, and lutein, as confirmed by HPLC-DAD and did not degrade during extraction as detected by FTIR analysis. However, extraction with a high temperature in UAE changed carotenoid isomerization from all trans to x-cis lycopene. Additionally, the anti-inflammatory properties of this ethanolic extract on THP-1 cells were investigated. As a result, the extract at the concentration of 0.25–1.00 µg/ml should be considered for its benefit in enhancing IL-1β cytokines and safe for THP 1 cell.

Keywords:

• Thai gac fruit
• ultrasonic treatment
• antioxidant properties
• inflammatory properties
• THP-1 cell

PUBLIC INTEREST STATEMENT

In this research, the extraction of carotenoids from gac fruit pericarp assisted with ultrasonic was study. The extraction with high temperature did not increase carotenoid contents. The optimal condition of ultrasonic-assisted extraction was obtained by using absolute ethanol as an effective solvent and extracting at 75°C for 15 min. This carotenoid extract possessed the highest antioxidant activity and carotenoid level. Moreover, the improvement of extraction yield was received while the structure and properties of carotenoids were not affected as confirmed by FTIR. The extract of gac fruit pericarp did not suppress pro-inflammatory cytokine and nor did it affect the level of anti-inflammatory cytokine.

Competing Interests

The authors declares no competing interests.

Acknowledgements

This research was supported by the Graduate Program Scholarship from Graduate School, Kasetsart University.

Cover Image

Source: Author.

Additional information

Funding

This work was supported by the Graduate School, Kasetsart University [Graduate Program Scholarship];

Notes on contributors

Supassara Natnoi

Supassara Natnoi is doing her Master Degree in Product Development with scholarship obtained from Graduate School, Kasetsart University for studying in Department of Product Development, Faculty of Agro-Industry, Bangkok, Thailand.

Tantawan Pirak

Dr.Tantawan Pirak is an Assistant Professor at Department of Product Development, Faculty of Agro-Industry, Kasetsart University, Bangkok, Thailand since 2007 until now. She received her Ph.D. in Food Technology from Chulalongkorn University, Thailand in 2007. Her research expertise is the development of functional ingredients and functional meat products, natural extracts and their utilization in food, chitosan and hydrocolloids in food, protein hydrolysate and functional peptides and interactions of food macromolecules with functional ingredients. Her research interest and future research is in the field of the study using in vitro gut model system.