Reactive oxygen species cause cytotoxic effects. The body requires the uptake of exogenous compounds with antioxidant potential. Black seed (BS) is a plant that contains at least one active lipid soluble antioxidant, thymoquinone. Fractionation of the seed components yielded antioxidant compounds in both the water soluble and lipid soluble fractions. The objective of the study was to determine the safety of the fractionated compounds and compare their potency with pure thymoquinone and vitamin E on A549 cells in culture for 24, 48 and 72 hours.
Results: Black seed extracts and pure thymoquinone showed markedly reduced levels of MDA for the duration of the study. The vitamin E dosage used led to greater toxicity and cellular damage rather than cell protection. Cellular proteins levels after 24 hours showed cells in BS + ETOH extract group had the highest metabolic activity. However, at 72 hours, the activity was shifted and showed the least amount of protein synthesis. As for vitamin E, the results were consistent throughout all three phases showing slow metabolic activity. Cell number was decreased after 24 hours in thymoquinone treated cells, and remained reduced for the duration of the study. The BS+H2O fraction showed a similar trend to thymoquinone, where as the BS+ETOH fraction showed a negative shift in cell number at 48 hours when compared with the control.
Conclusion: The study concludes that of the two BS extracts, the BS+H2O extract had the greatest effect on the cell viability and function.