The paper describes the use of photochemiluminescence assay (PCL) and DPPH method for the measurement of lipid-soluble antioxidants capacity (ACL) of six commercially available cold-pressed, non-refined flaxseed, walnut, rapeseed, pumpkin seed, evening primrose and black cumin oils. The cold-pressed plant oils are rich in various valuable bioactive compounds, e.g., tocopherols, tocotrienols, carotenoids, sterols, phospholipids and may reveal the antioxidant properties. The photochemiluminescence analysis (PCL) and free radical scavenging activity toward DPPH. were fully applicable for the evaluation of the antioxidant capacity of lipophilic fraction of samples and the outcomes correlated (r = 0.91). The highest ACL exhibited black cumin oil in case of both methods.
Practical applications: Photochemiluminescence analysis and radical scavenging activity toward DPPH. were fully applicable for the evaluation of the antioxidant capacity of lipophilic fraction of oil samples. However, providing a simple and reliable analytical method to detect the antioxidant capacities at very low concentrations of antioxidants in the sample is of major interest. Photochemiluminescence analysis shows many advantages over the other methodologies as it is fully automatic, sensitive, quick and does not require any time-consuming or complicated sample preparation steps that is needed in case of, e.g., DPPH method.