A novel LC-MS/MS method to characterize the antimicrobial lipid glycerol monolaurate in global human milk.

Glycerol monolaurate (GML), a monoglyceride found in human milk (HM), has antimicrobial properties against a broad spectrum of bacteria, viruses, and fungi. In this study, an LC-MS/MS method was developed and validated for quantifying GML in HM based on quantification of two distinct isomers, 1-monolaurin and 2-monolaurin. The method validation included assessments of selectivity (no interferences), linearity (r ² range of 0.9954- 0.9985 and 96 of 98 individual points having residual <15%), accuracy (average recovery of 96.4% across both isomers and a range of spiked levels), and precision (total GML repeatability 6.6% RSD and intermediate precision 9.7% RSD). This validated method was used to measure the concentration of GML in unpasteurized HM from 60 mothers and compared geographical locations (Cincinnati and Shanghai), lactation time (weeks 2 and 26), and self-reported maternal allergy status (yes or no). Our findings suggest GML concentration in unpasteurized HM is considerably lower than previously reported in a study characterizing pasteurized HM. The data reported here highlights a novel, validated method used to quantify GML in HM and identified no differences in total GML concentrations when comparing HM from different geographical locations, lactation times, and mother's allergy status.
Competing Interests: Declaration of Competing Interest TV, NAM, SDM, LB, RS, MAG, and SCP are all employees of Reckitt/Mead Johnson Nutrition, NS was previously employed by Reckitt/Mead John Nutrition and ALM received funding from Reckitt/Mead Johnson Nutrition for the GEHM study.
(Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)