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Eight new bis-styryllactones, goniolanceolatins A-H (1-8), possessing a rare α,β-unsaturated δ-lactone moiety with a (6S)-configuration, were isolated from the CH2Cl2 extract of the stembark and roots of Goniothalamus lanceolatus Miq., a plant endemic to Malaysia. Absolute structures were established through extensive 1D- and 2D-NMR data analysis, in combination with electronic dichroism (ECD) data. All of the isolates were evaluated for their cytotoxicity against human lung and colorectal cancer cell lines. Compounds 2 and 4 showed cytotoxicity, with IC50 values ranging from 2.3 to 4.2 μM, and were inactive toward human noncancerous lung and colorectal cells. Compounds 1, 3, 6, 7, and 8 showed moderate to weak cytotoxicity. Docking studies of compounds 2 and 4 showed that they bind with EGFR tyrosine kinase and cyclin-dependent kinase 2 through hydrogen bonding interactions with the important amino acids, including Lys721, Met769, Asn818, Arg157, Ile10, and Glu12.

Two new alkaloids, (−)-goniolanceolactam (1) and 2-acetyl-3-amino-1,4-naphthoquinone (2), along with two known naphthoquinone alkaloids, 2-acetyl-3-amino-5-hydroxy-1,4-naphthoquinone (3) and cleistopholine (4) were isolated from the cytotoxic, dichloromethane root extract of Goniothalamus lanceolatus (Annonaceae). The structures were elucidated by spectroscopic techniques and the absolute configuration of 1 was established by single-crystal X-ray diffraction. Alkaloid 1 showed cytotoxic activity on human colon and lung cancer cell lines with IC50 values ranging from 5.32 to 9.91 μM. © 2018 Phytochemical Society of Europe

Ethnopharmacological relevance Malaria, a devastating infectious disease which was initially recognized as episodic fever, is caused by parasitic protozoan of the genus Plasmodium. Medicinal plants with ethnobotanical information to treat fever and/or malaria has been the key element in identifying potential plant candidates for antimalarial screening. Goniothalamus lanceolatus Miq. (Annonaceae) is used as a folk remedy, particularly to treat fever and skin diseases. Aim of the study In this context, supported with previous preliminary data of its antiplasmodial activity, this study was undertaken to determine the in vitro antiplasmodial and cytotoxicity activities of G. lanceolatus crude extracts and its major compounds. Materials and methods The in vitro antiplasmodial activity was determined by parasite lactate dehydrogenase (pLDH) assay on chloroquine-sensitive (3D7) and chloroquine-resistant (K1) strains of Plasmodium falciparum. The cytotoxicity activity was evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on hepatocellular carcinoma (HepG2) and normal liver (WRL-68) cell lines. Results The root methanol extract possessed potent antiplasmodial activity against both P. falciparum 3D7 and K1 strains (IC50 = 2.7 μg/ml, SI = 140; IC50 = 1.7 μg/ml, SI = 236). Apart from the DCM extract of stem bark and root that were found to be inactive (IC50 > 50 μg/ml) against 3D7 strain, all other tested crude extracts exhibited promising (5 30 µg/ml, CC50 > 10 µM, respectively), except for the hexane and DCM extracts of root, which exerted mild cytotoxicity on HepG2 cell line (IC50 Conclusions This study suggests that the root methanol extract and compound C (Parvistone D) obtained from G. lanceolatus are highly potential for exploitation as source of antimalarial agents. Parvistone D is identified as one of the bioactive styryl lactones found in the plant extract. It is also noteworthy, that the extract and compound were more active against chloroquine-resistant (K1) strain of P. falciparum. Further studies are being carried out to assess their toxicity profile and antimalarial efficacy in animal model.

This study is aimed at investigating the antiplasmodial activity and acute toxicity of the methanol (MeOH) extracts of the leaves and roots, and the dichloromethane (DCM) extracts of the stem bark, leaves, and roots of Goniothalamus lanceolatus. Phytochemical analysis was then carried out on the most active extract. In vivo antiplasmodial activity was assessed using the 4-day suppressive test against Plasmodium berghei ANKA (PbANKA) in mice. The plant extracts were administered intraperitoneally (i.p.) as a single dose (30 mg/kg) starting 4 h after infection. At a dose level of 30 mg/kg (i.p.), the DCM extracts of the stem bark and leaves, and the MeOH root extracts, prolonged the survival period of infected mice compared to that of the negative control. In addition, all crude extracts, except for the DCM root extract, exhibited parasitemia suppressive activity. The highest level of parasitemia suppression was recorded in mice treated with the DCM stem bark extract at 66.3%. No mortality was observed in mice treated with the DCM extracts of the stem bark and leaves, and the MeOH extract of the leaves, indicating that the LD50 is greater than 300 mg/kg. On the other hand, both the MeOH and DCM extracts of the roots showed toxic effects at a dose of 300 mg/kg (i.p) with an 83.3% mortality rate. The results obtained indicate that the stem bark of G. lanceolatus (DCM crude extract) possesses good antiplasmodial activity against PbANKA infected mice without causing acute toxicity. Five known styrylpyrone derivatives namely goniodiol 1, 8-epi-9-deoxygoniopypyrone 2, 9-deoxygoniopypyrone 3, digoniodiol 4 and goniothalamin 5 have been isolated from the bark of Goniothalamus lanceolatus (DCM crude extract). The structures and stereochemistry of all compounds were elucidated by interpretation of spectroscopic data. This study provides a scientific basis to support the traditional use of the plant as a remedy for malaria.

This paper reports for the first time phytochemical study on Meiogyne monosperma (Annonaceae) which was collected from National Park, Pahang, Malaysia. The isolation and purification steps involve column chromatography, centrifugal thin layer chromatography and preparative thin layer chromatography lead to isolation of four triterpenes, lupeol, campesterol, β-sitosterol; a sesquiterpene, β-selinenol and two alkaloids, liriodenine and lanuginosine.