Vitamin A and vitamin E isoforms stability and peroxidation potential of all-in-one admixtures for parenteral nutrition

Background: In all-in-one admixtures (AIOs), vitamins can be degraded and lipid can be peroxidized by light exposure, oxygen action, and multiple chemical interactions. Aim: We investigated the impact of three commercial lipid emulsions and two multivitamin preparations on vitamin A and vitamin E chemical stability and lipid peroxidation potential of AIOs. Methods: A soybean oil (Soy), soybean/medium-chain triacylglycerol oil (MCT), and olive/soybean oil (Olive)-based emulsion (all 20%), and a lyophilized (Lyo) and emulsified (Emu) multivitamin compounds, were tested. Two AIOs for each lipid emulsion were prepared, the former with Lyo and the latter with Emu. The concentrations of retinol palmitate, α-γ-δ-tocopherol, and malondialdehyde were analyzed in AIOs, immediately (T0) and 24 hours (T24) after compounding. Results: Retinol palmitate, and α- and γ-tocopherol were more stable in MCT-AIOs than in both Soy-AIOs and Olive-AIOs (p < 0.013; p < 0.001 respectively). Furthermore α-tocopherol was more stable in Lyo-AIOs than in Emu-AIOs (p < 0.004). Malondialdehyde (MDA) increased differently among the admixtures; however the concentrations were similar in all AIOs at T24. Conclusions: The differences in retinol palmitate stability were due both to lipid emulsions per se and to interaction between lipid emulsions and multivitamin preparations. The α-γ-tocopherol stability depended on both lipid emulsions and multivitamin preparations. In tested AIOs there was a different degradation rate of fat-soluble vitamins to keep the same lipid peroxidation level, since MDA concentrations at T24 were similar among AIOs.