Manuka honey, which shows strong nonperoxide-dependent antibacterial activity, contains unique components, such as methyl syringate 4-O-_-D-gentiobioside (leptosperin) and its aglycone,methyl syringate (MSYR). We investigated the absorption and metabolism of these components in manuka honey.

Manuka honey (15 g) was fed to healthy human volunteers.  MSYR-GA, MSYR-S, and MSYR were detected in both plasma and urine. In conjunction with the disappearances, a significant amount of metabolites along with trace leptosperin was excreted in urine within 4 h.

Akari Ishisaka1,2, Shinichi Ikushiro3, Mie Takeuchi1, Yukako Araki1, Maki Juri1, Yui Yoshiki1,
Yoshichika Kawai4, Toshio Niwa5, Noritoshi Kitamoto1,2, Toshiyuki Sakaki3, Hirohito Ishikawa6
and Yoji Kato1,