. Mechanisms underlying the anti-inflammatory actions of boswellic acid derivatives in experimental colitis.

The TLC method developed allows unambiguous identification of three different olibanum samples (Boswellia papyrifera, Boswellia serrata, Boswellia carterii/Boswellia sacra). Evidence on the specific biosynthesis routes of these Boswellia species is reported.

3‐O‐Acetyl‐11‐oxo‐β‐boswellic acid (AKBA), found in incense, is a potent inhibitor of 5‐lipoxygenase, p38 and p42 MAP kinase and topoisomerases. Starting from crude extracts from incense, procedures are presented for the efficient large‐scale synthesis of AKBA and other boswellic acids (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

In extracts prepared from various fruits as well as in fruit juices a single tryptophan glycoconjugate was detected by HPLC-MS analysis. Product ion spectra demonstrated the N-glycosidic linkage of a hexose moiety to the indole nitrogen. For structure elucidation, the novel tryptophan glycoside was isolated from pear juice and identified as N(1)-(beta-D-glucopyranosyl-(4)C(1))-L-tryptophan by (1)H, HH-COSY and (13)C NMR spectroscopy. Finally, we disclosed the biosynthetic origin of the novel tryptophan metabolite by demonstrating the enzymatic glycosylation of deuterium-labeled tryptophan, which was applied to pear fruit.