# Supercritical CO2 Extraction of Bioactive Compounds from Corn Grains (Zea mays L., Hybrid Pri-15-7-16) with Metabolomic Profiling and Confocal Laser Microscopy

## TL;DR

This study uses supercritical CO2 to extract bioactive compounds from corn grains and identifies optimal extraction conditions and compound distribution.

## Contribution

The study introduces optimized supercritical CO2 extraction parameters and provides detailed metabolomic profiling and visualization of bioactive compound distribution in corn grains.

## Key findings

- Optimal extraction conditions were 200 bar pressure and 55 °C, yielding 2.2 mg/g of bioactive compounds.
- Confocal microscopy revealed autofluorescent compounds concentrated in pericarp and aleurone layers.
- Metabolomic analysis identified 44 compounds, including 30 polyphenolic compounds and 14 others like amino acids and fatty acids.

## Abstract

This study aimed to optimize supercritical CO2 extraction conditions, analyze bioactive compounds, and visualize their distribution in corn grains (Zea mays L., hybrid Pri-15-7-16). The optimal extraction conditions were identified as a pressure of 200 bar and a temperature of 55 °C, yielding 2.2 mg/g of bioactive compounds. The distribution of autofluorescent compounds within corn grain tissues was visualized using confocal laser scanning microscopy. Image analysis showed that the pericarp and aleurone layer cell walls were rich in autofluorescent compounds, while the endosperm cell walls exhibited low autofluorescence. Metabolomic analysis, combining high-performance liquid chromatography and mass spectrometry, identified 44 compounds in the extracts, including 30 polyphenolic compounds from subgroups such as polyphenolic acids, flavones, flavan-3-ols, flavonols, and anthocyanidins as well as 14 compounds from other chemical groups, including amino acids and fatty acids.