Grey mangrove (Avicennia marina) is a traditional medicine used for the treatment of various diseases, including rheumatism and ulcers; however, the compounds responsible for its curative effects remain largely unknown. Triterpenoids are a diverse group of plant-specialized metabolites derived from a common precursor, 2,3-oxidosqualene. Triterpenoids are potentially responsible for the beneficial effects of A. marina; however, the chemical profiles of triterpenoids in A. marina and their biosynthetic genes have not been identified. Cytochrome P450 monooxygenases (P450s) have key roles in the structural diversification of plant triterpenoids by catalyzing site-specific oxidation of triterpene scaffolds. Recent studies have revealed that the CYP716 family represents the most common clade of P450s involved in triterpenoid biosynthesis. In this study, we performed triterpenoid profiling and RNA sequencing of A. marina leaves. Mining of CYP716 family genes and enzymatic activity assays of encoded proteins revealed that CYP716A259 catalyzed oxidation at the C-28 position of the pentacyclic triterpene skeletons of β-amyrin, α-amyrin, and lupeol to produce oleanolic acid, ursolic acid, and betulinic acid, respectively. The other functionally defined P450, CYP716C53, catalyzed the C-2α hydroxylation of oleanolic acid and ursolic acid to produce maslinic acid and corosolic acid, respectively. The possible involvement of CYP716A259 and CYP716C53 in the biosynthesis of these health-benefiting compounds in A. marina leaves, and the possible contribution of the resulting compounds to the reported bioactivities of A. marina leaf extract, are discussed.

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Using various chromatographic methods, one new lanostane triterpene, 3α-hydroxylanosta-8,24E-dien-26-oic acid (1), one new lignan, matairesinol 4′-O-β-Dglucopyranoside (2) along with five known compounds, ecdysone (3), 20-hydroxyecdysone (4), 20-hydroxyecdysone 2,3-monoacetonide (5), turkesterone (6), and polypodine B (7) were isolated from the leaves of Vitex trifolia L. Their structures were elucidated by 1D-, 2D-NMR spectroscopic analysis, HR-ESI-MS, CD, and by comparing with the NMR data reported in the literature.

Six sesquiterpenoids were isolated from a methanol extract of Curcuma aeruginosa rhizomes by using various chromatographic separations. Their structures were elucidated as pyrocurzerenone (1), dehydrochromolaenin (2), curzeone (3), linderazulene (4), curzerenone (5), and 8,12-epoxy-1(10),4(15),7,11-germacratetraen-6-one (6) by extensive NMR spectroscopic analysis as well as comparison with the reported data. This is the first report of isolation of compounds 1, 2, 4, and 6 from C. aeruginosa.