Scientists in the US have shown that dietary intake of glucoraphanin, a compound found in broccoli sprouts, reduces the negative effects of diesel exhaust particles on asthma and allergies. Diesel exhaust particles contain a range of redox active compounds that irritate the linings of the airways by causing oxidative stress. This irritation is even worse in asthmatics and allergy sufferers.
Glucoraphanin is a precursor for sulforaphane, which stimulates the expression of around 200 antioxidant producing enzymes. Antioxidants counteract the effects of oxidising species from pollutants in the tissues lining the airways.
The sprouts of three to four day old broccoli plants are particularly rich in glucoraphanin, although it is still present in older broccoli plants. Other cruciferous vegetables such as cauliflower, cabbage and, kale are also good sources of glucoraphanin.
In their study the group based at the David Geffen School of Medicine at the University of California, Los Angeles, exposed 29 people with allergies to 300µg of diesel exhaust particles, a dose equivalent to around 40 hours spent breathing polluted air near a typical Los Angeles highway. Subjects who drank juice enriched with 100µmol broccoli sprout extract before exposure to diesel exhaust particles had a significantly reduced immune response.
Read the full article in Chemistry World»
Read the original journal article in Food & Function:
Sulforaphane-rich broccoli sprout extract attenuates nasal allergic response to diesel exhaust particles
David Heber, Zhaoping Li, Maria Garcia-Lloret, Angela M. Wong, Tsz Ying (Amy) Lee, Gail Thames, Michael Krak, Yanjun Zhang and Andre Nel
Food Funct., 2014, Advance Article, DOI: 10.1039/C3FO60277J