Ursane-type triterpenoids, steroids and phenolics from the stem bark and leaves of Nauclea orientalis (L.) L. (Rubiaceae). (June 2022)

• Record Type: Journal Article
• Authors: Songoen, Weerasak; Brecker, Lothar; Yooboon, Thitaree; Bullangpoti, Vasakorn; Pluempanupat, Wanchai; Schinnerl, Johann
• Is Part Of: Biochemical systematics and ecology. Volume 102(2022)
• Publication Date: 2022-06
• Subjects: Nauclea orientalis -- Rubiaceae -- Stem bark -- Leaves -- Ursane-type triterpenoids -- Contact toxicity; Chemotaxonomy -- Periodicals; Biochemical variation -- Periodicals; Ecology -- Periodicals; Biochemistry -- Periodicals; Ecology -- Periodicals; Chimiotaxinomie -- Périodiques; Variation biochimique -- Périodiques; Écologie -- Périodiques; 578.012
• DOI: 10.1016/j.bse.2022.104401
• Languages: English
• ISSNs: 0305-1978

Abstract

Abstract: Phytochemical investigation of the stem bark and leaf extract of Nauclea orientalis led to the isolation and identification of the three ursane-type triterpenoids rotundic acid, (3β)-3, 19, 23, 24-tetrahydroxyurs-12-en-28-oic acid, 3-oxo-19, 23, 24-trihydroxyurs-12-en-28-oic acid, the two steroids β-sitosterol, β-sitostenone, the two megastigmane derivatives blumenol A and blumenol A glucoside, the isocoumarine trans -4-hydroxymellein, as well as the flavonole glycoside rutin. From the crude stem bark extract, we performed an anti-bacterial assay against four Gram positive and six Gram negative bacterial strains. An acetylcholinesterase inhibitory assay was performed from the crude extracts and rotundic acid, (3ß)-3, 19, 23, 24-tetrahydroxyurs-12-en-28-oic acid and β-sitostenone. Both assays showed only weak effects. Contact toxicity determined via topical application revealed increased mortality of Spodoptera exigua caterpillars. The chemophenetic significance of ursane-type triterpenoids for the genus Nauclea is discussed briefly. Graphical abstract: Image 1 Highlights: Three ursane-type triterpenoids and six other compounds could be isolated from Nauclea orientalis . 3-oxo-19α, 23, 24-trihydroxyurs-12-en-28-oic acid (3 ) was isolated the first time from a Rubiaceae species. The lipophilic stem bark extract showed contact toxicity on Spodoptera exigua larvae.