Cruciferous vegetables like broccoli, cabbage, and kale contain a powerful and biologically active antioxidant – glucoraphanin1. Through a process called hydrolysis, sulfur-containing glucoraphanin is metabolized into the biologically active isothiocynate sulforaphane, which is associated with a variety of positive effects stemming from its antioxidant activity2,3.
For example, sulforaphane2,3:
- Releases hydrogen sulfide when cooked, producing a cardioprotective effect similar to that of garlic
- Induces phase II enzymes, an important part of the body’s detoxification pathways
- Increases expression of antioxidant enzymes
- Exerts other protective antioxidant effects
Glucoraphanin is a type of glucosinolate, a sulfur-containing compound associated with a pungent aroma and spicy taste. Glucobrassicin and gluconastutin are two other types of glucosinolates – differentiated by their amino acid composition – prod
uced by cruciferous vegetables like broccoli. When these glucosinolates go through hydrolysis, they enter their biologically active form, then called isothiocynates1.
A novel antioxidant is a broccoli seed extract standardized to yield 13 percent glucoraphanin, which metabolizes to sulforaphane and activates Nrf-2 pathways to produce4:
- Antioxidants for reducing oxidative stress
- Phase 2 enzymes, detoxifiers vital for the body’s natural detoxification process
Oxidative stress is a process caused by free radicals – unstable molecules formed during both natural body processes and from exposure to toxins5. Activation of Nrf-2 pathways help target harmful inflammation, thus limiting the extent and magnitude to which inflammation occurs6.
Oxidative stress and unhealthy inflammation is often a primary cause for systemic imbalances in the human body. These imbalances are connected to conditions like cancer, cardiovascular disease, and diabetes7.
- Fahey, J.W., Zalcmann, A.T. & Talalay, P. The chemical diversity and distribution of glucosinolates and isothiocyanates among plants. Phytochemistry 2001; 56: 5-51.
- Navarro SL, Schwarz Y, Song X, et al. Cruciferous vegetables have variable effects on biomarkers of systemic inflammation in a randomized controlled trial in healthy young adults. J Nutr. 2014; 144(11):1850-7.
- Bryan, HK, Olayanju, A, Goldring, CE, Park, BK. The Nrf2 cell defense pathway: Keap1-dependent and -independent mechanisms of regulation. Biochem Pharmacol. 2013; 85(6):705-717.
- Turpaey KT. Keap 1-Nrf2 signaling pathway: mechanisms of regulation and role in protection of cells against toxicity caused by xenobiotics and electrophiles. Biochemistry (Mosc) 2013; 78(2):111-126.
- Lee, Jong Hun et al. Dietary phytochemicals and cancer prevention: Nrf2 signaling, epigenetics, and cell death mechanisms in blocking cancer initiation and progression. Pharmacol Ther 2013; 137(2): 153-171.
- Davidson, RK et al. Sulforaphane represses matrix-degrading proteases and protects cartilage from destruction in vitro and in vivo. Arthritis Rheum. 2013.
- Lugrin, J, Rosenblatt-Velin, N, Parapanov, R, Liaudet, L. The role of oxidative stress during inflammatory processes. Biol Chem 2013.
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