Abstract
The study recommends the Artemisia nilagirica (Clarke) Pamp. essential oil (ANEO) as plant-based shelf-life enhancer of millets against fungal, aflatoxin B1 (AFB1) contamination and lipid peroxidation with favourable safety profile. Chemical characterisation of ANEO through GC-MS, recorded 1,5-heptadiene-4-one,3,3,6-trimethyl (32.72%)as the main compound, followed by Artemisia alcohol (13.40%), alpha lonone (4.55%), benzene, methyl (1-methylethyl) (2.97%) and 1-cyclohexene-1-carboxaldehyde,4-(1-methylethyenyl) (2.23%). The mycoflora analysis of millet samples showed Aspergillus flavus strain[LHP(R)-5] as the most AFB1 secreting strain. The ANEO inhibited growth and AFB1 production by the toxigenic strain at 1.4 and 1.0 µL mL−1, respectively, and also possess broad fungitoxic spectrum. The decrement in membrane ergosterol content, enhanced leakage of cellular Ca2+, K+ and Mg2+ ions along with SEM and TEM study of ANEO-treated cell denotes plasma membrane as antifungal site of action. The ANEO also showed strong antioxidant activity as determined by DPPH• and ABTS•+ assays having IC50 value 2.51 and 1.07 µL mL−1, respectively. More than 70.78% protection of Ragi samples from fungal contamination was observed during in situ trial. The ANEO showed favourable safety profile with high LD50 value (7528.10 µL kg−1) for male mice and also exhibited non-phytotoxicity for Ragi seeds germination.
Acknowledgment
Authors are thankful to Head, CAS in Botany, Banaras Hindu University, DST-PURSE and ISLS, Banaras Hindu University, Varanasi for laboratory facilities and SAIF, AIIMS, New Delhi for SEM and TEM analysis.
Disclosure statement
No potential conflict of interest was reported by the authors.