A highly efficient extraction protocol for metabolic profile analysis of avocado mesocarp samples using LC-MS

Authors: ALTOMARE, ANTHONY - University Of Central Florida; ANYIAM, NGOZI - University Of Central Florida; HUO, QUN - University Of Central Florida; Freeman, Barbara; ELTAHER, SHAMSELDEEN - Oak Ridge Institute For Science And Education (ORISE); Ali, Gul

Submitted to: American Chemical Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 9/2/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: Avocados are subtropical fruits widely recognized for their health benefits. Every year, people around the world consume around 11 billion pounds of avocados. They are not only a great source of fiber, vitamins, and minerals, but also contain healthy fats and a variety of other beneficial compounds - some of which are still being discovered. To better understand the nutritional makeup of avocados, we developed a new method to extract and study these compounds. This method uses two solvents to pull out both water-loving and fat-loving substances from the fruit. The process is quick, taking less than an hour, and it neatly separates the avocado sample into two layers each containing different compounds. Analyses of these layers using a technique call liquid chromatography-mass spectrometry, LC-MS, we detected a wide variety of compounds, including many that have not been reported before. In fact, our method produced extracts that were about ten times more concentrated. In summary, this new extraction and analyses approach provides a powerful tool for uncovering the full nutritional richness of avocados, helping researchers and breeders select the most healthful varieties for consumers and stakeholders.

Technical Abstract: Avocados are nutrient-dense subtropical fruits known for their health benefits. Globally, approximately 11 billion pounds of avocados are consumed annually. Avocado is a good source of fiber, rich in vitamins and minerals and has a high content of mono- and poly-unsaturated healthy fat as well as yet-to-be discovered metabolic compounds. Metabolic profile analysis can enhance our understanding of the molecular composition of avocados and can help select cultivars with the highest nutritional value for consumers. Here we report a new extraction protocol for metabolic profile analysis of avocados using LC-MS. In this protocol, a mixed, two-phase solvent system, methanol and hexane in a 1/1 volume ratio was introduced to extract compounds from avocado mesocarp samples. Avocado contains a high percentage of hydrophobic compounds such as lipids and fatty acids, as well as polar organic solvent- and water-soluble metabolites. By using a methanol/hexane two-phase mixed solvent system, avocado mesocarp was more uniformly disrupted during mechanical homogenization, exposing both polar and non-polar compounds to the solvent. Our extraction protocol, which completes in under an hour, clearly separated the samples into two solvent phases with a clear methanol bottom layer, a top hexane layer, and an intermediate insoluble residue suspended in-between the two layers. LC-MS analysis of the methanol layer using a positive ion ESI (electrospray ionization) revealed a large number of both polar and non-polar compounds that have not been reported previously, and the concentration of the extract is approximately ten times higher than the extract obtained using methanol alone. In summary, our study established a highly efficient extraction and LC-MS analysis protocol to study the metabolomic profiles of avocado mesocarp samples.