Two tetranortriterpenoids, kokosanolide A (1) and C (2) were isolated from the seeds and three onoceranoid-type triterpenoids: kokosanolide B (3), 8,14-secogammacera-7,14-diene-3,21-dione (4) and a 1.5:0.5 mixture of 8,14-secogammacera-7,14(27)-diene-3,21-dione (5) and compound 4 were isolated from the bark of kokossan (Lansium domesticum). Complete ¹H- and ¹³C-NMR data of the triterpenoids 1-5 are reported. The triterpenoids’ structures were elucidated primarily by means of high field 1D- and 2D-NMR, IR and HRMS spectral data. Triterpenoids 1-5 exhibited moderate to strong antifeedant activity against the fourth instar larvae of Epilachna vigintioctopunctata.

A new limonoid, pentandricine (1), along with three known limonoids, ceramicine B (2), 6-de(acetyloxy)-23-oxochisocheton (3), 6-de(acetyloxy)-23-oxo-7-O-deacetylchisocheton (4), have been isolated from the stembark of Chisocheton pentandrus. The chemical structures of the new compound were elucidated on the basis of spectroscopic evidence. All of the compounds were tested for their cytotoxic effects against MCF-7 breast cancer cells. Compounds 1–4 showed weak and no cytotoxicity against MCF-7 breast cancer cells with IC₅₀ values of 369.84, 150.86, 208.93 and 120.09 μM, respectively.

Hidayat AT, et al. Nat Prod Sci. 2017 Dec;23(4):291-298. https://doi.org/10.20307/nps.2017.23.4.291

The high incidence of oral health issues and antibiotic resistance has stimulated research into discovering novel antimicrobial drugs. Prior evidence suggests that red betel leaves (Piper crocatum Ruiz and Pav) possess potential antimicrobial properties, including the presence of stigmasterol, a bioactive compound. However, the proteins precisely inhibited by stigmasterol compounds have not been identified as target proteins in the mechanism of action of stigmasterol as an oral antimicrobial agent or proteins involved in the virulence system of pathogenic oral microorganisms. The objective of this research is to identify and predict the antimicrobial mechanism of action of the stigmasterol compound isolated from red betel against specific proteins using a molecular docking approach. The methods employed for this investigation are as follows: Stigmasterol extracted from P. crocatum Ruiz and Pav was utilized as a ligand. Positive controls for each protein were antibiotics or substrates. The study findings indicate that the stigmasterol compound exhibits antibacterial and antifungal properties against pathogenic oral microorganisms in vitro as well as in silico against the crucial antibacterial enzymes MurA and PBP in addition to the pivotal antifungal enzyme exo‐β‐1,3‐glucanase and lanosterol‐14‐α‐demethylase. Therefore, it can be inferred that the stigmasterol present in Red Betel leaves could potentially function as an antimicrobial agent by impeding the spread of pathogenic oral microorganisms.