Tomato skin extract, naringenin chalcone, shows strong inhibition of histamine release. According to recent research from Japan, "The anti-allergic activity of a tomato extract was studied by using an in vitro histamine-release assay.

The tomato skin extract exerted the strongest inhibition of histamine release. Chlorogenic acid, rutin and naringenin were identified in the 60% ethanol extract of tomato skin."

"However," T. Yamamoto and colleagues, Kikkoman Foods Inc., explained, "the extract contained an unknown compound which strongly inhibited histamine release. This active compound in tomato skin was identified as naringenin chalcone (trans-2'4'6'4-tetrahydroxychalcone). Naringenin chalcone inhibited histamine release with an IC value of 68 mcg/ml. The anti-allergic activity of the tomato skin extract was next investigated by the in vivo mouse ear-swelling response."

"We found that naringenin chalcone showed the strongest inhibitory effect of the polyphenols of the tomato skin extract. These results indicate that a tomato skin extract could inhibit allergic reactions," the authors concluded.

Yamamoto and colleagues published their study in Bioscience Biotechnology and Biochemistry (Anti-allergic activity of naringenin chalcone from a tomato skin extract. Biosci Biotechnol Biochem, 2004;68(8):1706-1711).