A Fast and Efficient Ultrasound-Assisted Extraction of Tocopherols in Cow Milk Followed by HPLC Determination.

Teresa Gervasi,Giovanna Loredana La Torre,Mattia Spano,Archimede Rotondo,Giacomo di Matteo,Andrea Salvo,Cinzia Ingallina

doi:10.3390/molecules26154645

Teresa Gervasi, Giovanna Loredana La Torre + Show 5 more

Open Access

https://doi.org/10.3390/molecules26154645

Copy DOI

Abstract

A fast HPLC method with fluorescence detector (FD) was developed for the determination of three tocopherols (TOCs) in milk samples from Modicana cattle breed. The ultrasound-assisted procedure was optimized for the extraction of TOCs prior to HPLC/FD analysis, reducing sample preparation time and allowing a fast quantification of α-tocopherol, δ-tocopherol and γ tocopherol. The optimized ultrasonic extraction combines an efficient and simple saponification at room temperature and a rapid HPLC quantification of TOCs in milk. The precision of the full analytical procedure was satisfactory and the recoveries at three spiked levels were between 95.3% and 87.8%. The linear correlations were evaluated (R2 > 0.99) and the relative standard deviation (RSD) values for intra-day and inter-day tests at three spiked levels were below 1% for the retention time and below 5.20% for the area at low level spiking. The proposed procedure, reducing the experimental complexity, allowed accurate extraction and detection of three TOCs in milk samples from Modicana cattle breed.

Highlights

Tocopherols (TOCs), together with tocotrienols, are fat-soluble compounds that make up the group of vitamin E
The influence of the solvent volume evidenced that the highest recovery yield was obtained if the milk-solvent ratio was 1:1
During the sample preparation the milk samples were spiked with saponification solution containing different concentrations of methanolic KOH solution

Summary

Introduction

Tocopherols (TOCs), together with tocotrienols, are fat-soluble compounds that make up the group of vitamin E. From the structural point of view, the TOCs can be considered tocol (6-hydroxy-chroman) derivatives, bearing a methyl group in position 2 and an aliphatic side chain with 16 carbon atoms (phytol). The four TOCs share the same hydroxy-chromic core connected to the saturated carbon chain and differ to each other by the methylated positions over the aromatic ring [2]. Evidence from several studies suggest that TOCs in vivo: (a) may protect lipids from oxidation; (b) may preserve biological membranes by tackling the peroxidation of polyunsaturated fatty acids triggered by free radicals generated inside the cells [3,4]; and,

Objectives

Methods

Results

Conclusion