Assessing the Levisticum officinale Koch. essential oil as a novel preservative for stored chia seeds (Salvia hispanica L.) with emphasis on probable mechanism of action

The present study was undertaken to explore the inhibitory effect of Levisticum officinale Koch. essential oil (LoffEO) on the growth and aflatoxin B-1 secretion by Aspergillus flavus (AF-LHP-SH1, aflatoxigenic strain) causing deterioration of stored chia seeds (Salvia hispanica). The chemical profile analysis of LoffEO by GC-MS analysis revealed the presence of alpha-terpinyl acetate (26.03 %) as a major component followed by terpineol (24.03 %) and citronellal (24.03 %). Results on antifungal and antiaflatoxigenic activity indicated that LoffEO at 2.0 and 1.75 mu L/mL caused complete inhibition of growth and aflatoxin B-1 production, respectively. Antifungal toxicity of LoffEO was strongly correlated with the inhibition of ergosterol content, leakage of cellular ions, and disintegration of membrane permeability. Reduction in cellular methylglyoxal by LoffEO indicated a novel antiaflatoxigenic mechanism of action. The LoffEO showed moderate free radical quenching activity in DPPH assay (IC50 = 26.10 mu L/mL) and exhibited remarkable inhibitory efficacy against lipid peroxidation of chia seeds. In addition, LoffEO presented strong in situ antiaflatoxigenic efficacy, and exhibited non-phytotoxic nature, acceptable sensory characteristics, and favorable safety profile (LD50 = 19786.59 mu L/kg), which recommends its practical utilization as a novel and safe preservative to improve the shelf life of stored chia seeds from fungal infestation and aflatoxin B-1 contamination.

Automated summary

The essential oil of Levisticum officinale Koch. showed significant inhibitory effects on the growth and aflatoxin B1 secretion of Aspergillus flavus, possibly through mechanisms such as inhibition of ergosterol content, leakage of cellular ions, and disintegration of membrane permeability. Additionally, the oil exhibited moderate free radical quenching activity and remarkable inhibition against lipid peroxidation, suggesting its potential use as a safe preservative for improving the shelf life of stored chia seeds.