Anti-Proliferative Acyl Phenols and Arylnonanoids from the Fruit Rind of Myristica malabarica Lam

Phytochemical investigation of the methanol extract of the fruit rind of Myristica malabarica led to the isolation of eight known compounds that were identified as malabaricones A-D, promalabaricones B and C, 1-(2,6-dihydroxyphenyl)tetradecan-1-one, and ericanone by comparison with literature spectroscopic data. The structures of malabaricones A-D, promalabaricone B, and 1-(2,6-dihydroxyphenyl)tetradecan-1-one were confirmed by X-ray crystallography. In vitro assay of the isolated phenols indicated that they exhibited moderate anti-proliferative activity against the A2780 human ovarian cancer cell. Compounds (1, 3, 5, 6 and 7) had the most potent activities, whereas the anti-proliferative activities of compounds 2 and 4 were less potent.

HPLC-Guided Isolation, Purification and Characterization of Phenylpropanoid and Phenolic Constituents of Nutmeg Kernel (Myristica fragrans)

Many studies on the biological activities of nutmeg continue to appear in the literature. The most common targets include GIT, CNS, oxidative stress and inflammation. However, results obtained from most studies are often inconsistent due to the variability of utilized samples, lack of standardized nutmeg products or insufficient amounts of pure compounds for comprehensive follow-up investigation. To address the consistency and supply issue we utilized available technology to develop a reproducible procedure for preparation of specific extracts and isolation of the major phenolic constituents present in nutmeg kemel. A well-defined and reproducible sequence of extraction, fractionation and chromatographic purification was adopted and was guided by HPLC fingerprinting. Spectroscopic methods, mainly NMR, and mass spectrometry were utilized to identify each compound. Thirteen compounds were isolated in a pure form and identified as: elemicin (1), isoelemicin (2), myristicin (4), surinamensin (5), malabaricone C (6), 2-(3'-allyl-2',6'-dimethoxy-phenyloxy)-l- acetoxy-(3,4-dimethoxyphenyl)-propyl ester (7), methoxylicarin A (8), licarin A (9), malabaricone B (10), licarin C (11), 5'-methoxylicarin B (12), licarin B (13), and 2-(3'-allyl-2',6'-dimethoxy-phenyloxy)-l-methyl-5-methoxy-1,2-dihydrobenzofuran (3, a new compound). With repeated isolation runs, these pure compounds can be prepared in quantities sufficient for biological evaluation as needed. The availability of purified compounds will also allow the development of specific, accurate, and sensitive analytical procedures for pharmacokinetic studies and for quality control of nutmeg products. Both aspects are essential for nutmeg-focused drug discovery. The same approach can also be adapted to other medicinal plants of potential interest.

The Blood-Brain Barrier Permeability of Lignans and Malabaricones from the Seeds of Myristica fragrans in the MDCK-pHaMDR Cell Monolayer Model

The blood-brain barrier (BBB) permeability of twelve lignans and three phenolic malabaricones from the seeds of Myristica fragrans (nutmeg) were studied with the MDCK-pHaMDR cell monolayer model. The samples were measured by high-performance liquid chromatography and the apparent permeability coefficients (P_app) were calculated. Among the fifteen test compounds, benzonfuran-type, dibenzylbutane-type and arylnaphthalene-type lignans showed poor to moderate permeabilities with P_app values at 10⁻⁸–10⁻⁶ cm/s; those of 8-O-4′-neolignan and tetrahydrofuran-lignan were at 10⁻⁶–10⁻⁵ cm/s, meaning that their permeabilities are moderate to high; the permeabilities of malabaricones were poor as their P_app values were at 10⁻⁸–10⁻⁷ cm/s. To 5-methoxy-dehydrodiisoeugenol (2), erythro-2-(4-allyl-2,6-dimethoxyphenoxy)-1-(3,4-dimethoxyphenyl)-propan-1-ol acetate (6), verrucosin (8), and nectandrin B (9), an efflux way was involved and the main transporter for 6, 8 and 9 was demonstrated to be P-glycoprotein. The time and concentration dependency experiments indicated the main transport mechanism for neolignans dehydrodiisoeugenol (1), myrislignan (7) and 8 was passive diffusion. This study summarized the relationship between the BBB permeability and structure parameters of the test compounds, which could be used to preliminarily predict the transport of a compound through BBB. The results provide a significant molecular basis for better understanding the potential central nervous system effects of nutmeg.