# A sustainable approach to extracting baobab oil: neat supercritical CO2 optimization

## TL;DR

This paper explores using supercritical CO2 to extract oil from baobab seeds in an eco-friendly way, achieving good quality oil with a sustainable method.

## Contribution

The study presents the first systematic optimization of neat supercritical CO2 extraction for baobab seed oil without co-solvents.

## Key findings

- Optimized extraction conditions yielded 9.3 ± 1.1 wt% oil with a favorable fatty acid profile.
- The extracted oil was solvent-free and suitable for cosmetic and nutraceutical applications.
- Solubility, not mass transfer, was the main limiting factor in the extraction process.

## Abstract

Baobab (Adansonia digitata) seeds are a source of valuable lipids with notable nutritional and functional attributes. In response to the rising demand for sustainable, high-quality oils in the cosmetic and nutraceutical sectors, there is an increasing interest in environmentally friendly extraction techniques that maintain lipid bioactivity while reducing the use of toxic solvents. This study represents the first systematic optimization of baobab seed oil extraction utilizing neat supercritical CO2 without co-solvents, employing response surface methodology. Under the optimized conditions of 77 °C and a CO2 density of 0.8 g mL−1, the extracted oil yield was 9.3 ± 1.1 wt%. Although this yield was lower than that achieved through conventional hot pressing (37 wt%), the extracted oil exhibited a fatty acid profile comparable to that of warm-pressed oil, with substantial levels of oleic (37 wt%), linoleic (29 wt%), and palmitic (30 wt%) acids, suggesting higher selectivity for free fatty acids. Furthermore, the scCO2 extracted oil retained a solvent-free purity, indicating its suitability for cosmetic and nutraceutical applications. Kinetic studies indicated that solubility, rather than mass transfer, was the primary limiting factor, with an optimal extraction flow rate of 4 mL min−1 over 25 minutes. These findings underscore the feasibility and selectivity of neat scCO2 extraction as an environmentally friendly alternative to traditional mechanical and solvent-based methods for obtaining high-quality baobab seed oil.

Baobab (Adansonia digitata) seeds are a source of valuable lipids with notable nutritional and functional attributes.