Zataria multiflora and bunium persicum essential oils as two natural antioxidants

Autoxidation is considered to be the main route of edible oil deterioration, which produces undesirable odors and flavors [attributed to primary and secondary products of unsaturated fatty acids] during storage and heating. Antioxidant activities of Zataria multiflora [ZMEO] and Bunium persicum [BPEO] essential oils [EOs] in linseed oil [containing higher omega-3 in vegetable sources] were studied with 4 indexes. Total phenol content, electropositive potential [by bleaching using violet ethanol solution of DPPH], antioxidant capacity [by radical cation of ABTS], scavenging activity of hydrogen peroxide and Fe-reducing power of the EOs were measured. Then ZMEO and BPEO [0.6, 1, 1.4, 1.8 mg/ml] were added to linseed oils; peroxide and tiobarbituric acid in 0[th]- 15[th] days [at 60°C] were compared with TBHQ [0.01, 0.02] and BHT [0.1, 0.2]. IC50 of ZMEO and BPEO in mentioned assays were 0.78 and 1.52; 0.11 and 7.50; 0.31 and 0.72 mg/ml and RP0.5 for reducing power assay was 0.76 and 2.12 mg/ml. Total phenolic compound of ZMEO and BPEO were 322 and 50.6 mg/ml. The best antioxidant levels of reductive oxidation were 600 for ZMEO and BPEO and 20 for TBHQ. PV and TBA values demonstrated that both of EOs in linseed oil had the same antioxidant activity in 600 ppm [ZMEO>BPEO] in 4 tests, and EOs will be used as natural antioxidants as a good replacement in 600 ppm with BHT [100] and TBHQ [10] as synthetic