Pharmaceutica Analytica Acta

Abstract

Agarwood (Aquilaria Crassna) Extracts Decrease High-protein High-fat Diet-induced Intestinal Putrefaction Toxins in Mice

Mamoru Kakino, Tsuyoshi Sugiyama, Hitomi Kunieda, Shigemi Tazawa, Hiroe Maruyama, Kazuhiro Tsuruma, Yoko Araki, Masamitsu Shimazawa, Kenji Ichihara, Hiroshi Mori and Hideaki Hara

Agarwood (Aquilaria spp.) is famous for its aromatic resin, but its leaves are also prized as a healthy tea in South East Asia. Previously, we reported that agarwood extract (Aquilaria sinensis and Aquilaria crassna) shows laxative effect via acetylcholine receptors in constipation model mice and rats. In the present study, we investigated the effects of agarwood (Aquilaria crassna) on intestinal toxins, such as indole derivatives and ammonium to investigate the enteral environment. Male mice received regimens of three types of food, CE-7 (normal diet), CE-2 (high-protein normal diet), and Quick Fat (high-protein high-fat diet). Extracts of agarwood (water extract of agarwood: WEA and ethanol extract of agarwood: EEA) were orally administered once daily for a week. We measured the contents of indole derivatives and ammonium in feces and also examined the Minimum Inhibitory Concentrations (MICs) of agarwood against nine strains of enterobacteria in vitro. As compared with CE-7, Quick Fat increased the contents of indoles and ammonium in fecal beads. Single administration and multiple administrations for 7 days of WEA at 1,000 mg/kg/day decreased the contents of indoles and ammonium in fecal beads; on the other hand, multiple administrations of EEA decreased contents of indoles, but not those of ammonium. Interruption of administration abolished the effects of WEA and EEA. Quick Fat delayed carmine egestion in the digestive tract and administration of WEA and EEA accelerated the carmine egestion. Both WEA and EEA showed significant antimicrobial activity against some urease-positive bacteria, such as Staphylococcus aureus, Clostridium difficile, and Bacteroides spp. In conclusion, feeding with Quick Fat (high-protein high-fat diet) increased fecal-containing toxins and delayed carmine egestion in mice. Administrations of WEA and EEA decreased fecal-containing toxins and accelerated carmine egestion, and the decrement of fecal-containing toxins was abolished in response to interruption of the administration.