Critical review on the immunomodulatory activities of carrot’s β-carotene and other bioactive compounds

Carrots (Daucus carota L.) are vegetables proven to have nutraceutical effects and beneficial for health due to its natural bioactive substances. One of the potential of carrots to maintain optimum health status is by regulating immune response. This literature review summarized the proposed immunomodulatory mechanisms of the antioxidant properties of carrot’s β-carotene and other bioactive compounds such as phenolic acid, flavonoid, polyacetylene and ascorbic acid via the anti-inflammatory, antioxidant and overall (innate and adaptive) immune response modulation. Overall, carrot’s bioactive compounds regulated pro-inflammatory and anti-inflammatory cytokines, reduced oxidative stress by decreasing the reactive oxygen species accumulation and improving antioxidant capacity and the expression of genes in order to prevent more damaging oxidative destruction. Carrots also modulated the immune components by regulating leukocytes, antigens, immunoglobulins, and histamine levels. Thus, the immunomodulatory activity makes carrots as a functional food source that has the potential to prevent and treat various diseases.