Plant-Derived Natural Antimicrobials as Sustainable Alternatives to Synthetic Preservatives in the Food Supply Chain

Abstract

Synthetic preservatives—sodium benzoate, potassium sorbate, sodium nitrite and the phenolic antioxidants BHA and BHT—underpin the safety and shelf life of the modern food supply, yet mounting toxicological scrutiny, tightening regulation and consumer rejection of chemical additives are eroding their acceptability; in 2026 regulators including the US FDA opened formal reassessments of BHA and BHT. Plant-derived antimicrobials offer a scientifically credible and sustainable alternative, combining broad-spectrum activity with renewable sourcing, biodegradability and high consumer acceptance. This review evaluates plant-derived antimicrobials as sustainable substitutes for synthetic preservatives across the entire farm-to-fork supply chain. Six compound classes—phenolics, terpenoid essential oils, organosulfur compounds, alkaloids, saponins and antimicrobial peptides—are examined with respect to chemistry, structure–activity relationships, antimicrobial spectrum and mechanism. Compiled minimum inhibitory concentrations (MICs) show that the principal actives carvacrol, thymol and cinnamaldehyde inhibit major foodborne pathogens (Escherichia coli, Salmonella, Listeria monocytogenes, Staphylococcus aureus) at roughly 128–400 µg/mL, with Gram-positive organisms generally more susceptible than Gram-negative.
Their multi-target mode of action—membrane disruption, proton-motive-force collapse, reactive-oxygen-species induction, efflux-pump and quorum-sensing inhibition, and DNA binding—confers a low propensity for resistance, and binary combinations exhibit marked synergy, lowering effective doses by up to 75–94% and mitigating sensory impact. Supply-chain applications spanning pre-harvest treatment, processing, active packaging and storage are reviewed, with documented shelf-life extensions of two- to threefold. A sustainability assessment contrasts the renewable, low-ecotoxicity profile of plant antimicrobials with the cost, stability and regulatory advantages that still favour synthetics, and identifies the principal translational barriers—dose–sensory trade-offs, formulation stability, matrix effects, cost and regulatory harmonisation. The review concludes that plant-derived antimicrobials are best deployed not as one-for-one replacements but as engineered components of hurdle-based, clean-label preservation systems.