• Journal of Life Science
• /
• v.25 no.11
• /
• pp.1298-1303
• /
• 2015

Machilus thunbergii (Lauraceae) is an evergreen tree cultivated in Korea and Japan. M. thunbergii has long been used as a traditional medicine in Korea, China, and Japan to treat various diseases, including edema, abdominal pain, and abdominal distension. In this study, dried stem bark of M. thunbergii extracted in methanol and extract was partitioned into n-hexane, CHCl₃, and BuOH. The CHCl₃-soluble extracts chromatographed on silica gel column using a CHCl₃/acetone and n-hexane/EtOAc mixture to afford Compound 1 and 2. Two dibenzylbutane lignans, macelignan (1) and meso-dihydroguaiaretic acid (2), were isolated from the CHCl₃-soluble extract of M. thunbergii stem bark. The structures of 1 and 2 were determined by ¹H- and ¹³C-NMR spectroscopic data analyses and a comparison with literature data. The tyrosinase inhibitory activity of the isolated compounds was evaluated. Among these compounds, Compound 2 strongly inhibited the monophenolase (IC₅₀=10.2 μM) activity of tyrosinase. A kinetic analysis showed that Compound 2 was a competitive inhibitor. The apparent inhibition constant (K_i) for Compound 2 binding to free enzyme was 4.8 μM. Based on these results, it can be concluded that meso-dihydroguaiaretic acid (2) is a potential candidate for the treatment of melanin biosynthesis-related skin diseases.

• Biomedical Science Letters
• /
• v.16 no.2
• /
• pp.91-95
• /
• 2010

Meso-dihydroguaiaretic acid (MDGA) is a medicinal herbal product isolated from the bark of Machilus thunbergii Sieb. et Zucc. (Lauraceae). It exhibits a neuroprotective effect and also exerts cytotoxicity to certain cancer cells. In the present study, we investigated whether or not MDGA inhibits inflammatory reaction through the inhibition of nitric oxide (NO) generation. The results showed that MDGA (5~$25 {\mu}M$) inhibited 100 ng/ml lipopolysaccharide (LPS)- induced NO generation in macrophage Raw 264.7 cells in a concentration-dependent manner. We also measured the cytotoxic effects of MDGA on Raw 264.7 cells and found no evidence of cytotoxicity. The inhibition of NO generation by MDGA was consistent with the inhibitory effect on the expression of inducible nitric oxide synthase (iNOS). In addition, MDGA inhibited the LPS-induced gene expression of $interleukin-1{\beta}$ $(IL-1{\beta})$ as well as tumor necrosis $factor-{\alpha}$ $(TNF-{\alpha})$. The present results may provide that MDGA has anti-inflammatory properties through inhibition of the toll-like receptors (TLRs) pathway, and suggest that MDGA can be used as an anti-inflammatory agent.

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.195.2-195.2
• /
• 2003

The CH$_2$Cl$_2$ fraction of the bark of Machilus thunbergii Sieb. et Zucc. (Lauraceae) significantly protected primary cultures of rat cortical cells exposed to the excitotoxic amino acid, L-glutamate. Several lignans including (-)-isoguaiacin, meso- dihydroguaiaretic acid, machilin A, (+)-galbelgin, licarin A, (-)-sesamin, and (+)-guaiacin were isolated from the CH$_2$Cl$_2$ fraction using by bioactivity-guided isolation techniques. Among these lignans, (-)-isoguaiacin, meso-dihydroguaiaretic acid, licarin A and (+)-guaiacin had significant neuroprotective activities against glutamate-induced toxicity in primary cultures of rat cortical cells at concentration ranging from 0.1 ${\mu}$M to 10.0 ${\mu}$M. (omitted)

• Korean Journal of Pharmacognosy
• /
• v.21 no.4
• /
• pp.270-273
• /
• 1990

Antioxidant activity of diarylbutane type lignans was evaluated in TBA-reactant assay to elucidate the structure-activity relationship. The antioxidant potency of lignans increased with increasing the number of hydroxyl groups, with the exception of macelignan(I), which showed a more potent activity than demethyl meso-dihydroguaiaretic acid(III).

• Bulletin of the Korean Chemical Society
• /
• v.31 no.6
• /
• pp.1751-1752
• /
• 2010

• Applied Biological Chemistry
• /
• v.47 no.3
• /
• pp.366-369
• /
• 2004

Myristica fragrans Houtt were extracted in 80% aq. MeOH and solvent fractionated sing $CHCl_3$, EtOAc, n-BuOH and water, successively. The n-BuOH fraction gave three phenylpropanoids through application of silica gel column chromatographies. The chemical structures of the phenylpropanoids were determined by the interpretation of several spectral data, including NMR and MS as meso-dihydroguaiaretic acid (1), nectandrin B (2) and syringin methyl ether (3). Compound 1, which was first isolated from this plant by authors, showed inhibitory activities with $60.0{\pm}2.1%\;(100\;{\mu}g/ml),\;42.6{\pm}0.9%\;(140\;{\mu}g/ml)\;and\;12.2{\pm}0.2%\;(200\;{\mu}g/ml)$ on ACAT(acyl-CoA:Cholesterol Acyltransferase), chitin synthase III and HMG-CoA reductase (3-hydroxy-3-methylglutaryl coenzyme A reductase), respectively. Compound 3 showed inhibitory activities with $27.2{\pm}0.9%\;(100\;{\mu}g/ml),\;45.5{\pm}0.8%\;(200\;{\mu}g/ml)$ on ACAT and chitin synthase III.

• Natural Product Sciences
• /
• v.18 no.4
• /
• pp.227-232
• /
• 2012

Ten known compounds, 7-hydroxysauchinone (1), sauchinone (2), di-O-methyltetrahydrofuriguaiacin B (3), henricine (4), saucerneol K (5), meso-dihydroguaiaretic acid (6), (-)-guaiacin (7), (3R,4S)-4-(4-hydroxy-3-methoxyphenyl)-4-methoxy-3-methylbutan-2-one (8), (E)-7-(4-hydroxy-3-methoxyphenyl)-7-methylbut-8-en-9-one (9), and licarin A (10), were isolated from aerial part of Sarurus chinensis. The chemical structures of these compounds were determined on the basis of spectroscopic analyses including 2D NMR. Compounds 1 - 10 were evaluated for their cytotoxic activity against the HL-60, MCF-7, and A549 cancer cell lines in in vitro.

• Natural Product Sciences
• /
• v.23 no.1
• /
• pp.21-28
• /
• 2017

In our program to search for new AMP-activated protein kinase (AMPK) activators from plants that exert potential anticancer property, we found that an EtOAc extract of Myristica fragrans (nutmeg) activated AMPK enzyme in human breast cancer MCF-7 cells. Two major diarylbutane-type lignans, macelignan and meso-dihydroguaiaretic acid (MDGA), were isolated as active principles from this extract. Treatment of breast cancer cells with two compounds induced cellular apoptosis, evidenced by cleavage of poly-(ADP-ribose) polymerase (PARP) and Ser 15 phosphorylation of p53. Moreover, macelignan and MDGA significantly inhibited the colony formation of MCF-7 breast cancer cells on soft agar. Intraperitoneal injection of macelignan and MDGA (20 mg/kg) suppressed the tumor growth of 4T1 mammary cancer cells. These results indicate that the chemopreventive effects of two major diarylbutane-type lignans from Myristica fragrans (nutmeg) may be associated with induction of apoptosis presumably through AMPK activation.