In this study, we found that alpha-pinene (α-pinene) exhibits anti-inflammatory activity through the suppression of mitogen-activated protein kinases (MAPKs) and the nuclear factor-kappa B (NF-κB) pathway in mouse peritoneal macrophages. α-Pinene is found in the oils of many coniferous trees and rosemary. We investigated the inhibitory effects of α-Pinene on inflammatory responses induced by lipopolysaccharide (LPS) using mouse peritoneal macrophages. α-Pinene significantly decreased the LPS-induced production of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and nitric oxide (NO). α-Pinene also inhibited inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions in LPS-stimulated macrophages. Additionally, the activations of MAPKs and NF-κB were attenuated by means of α-pinene treatment. These results indicate that α-pinene has an anti-inflammatory effect and that it is a potential candidate as a new drug to treat various inflammatory diseases.

Three new flavonoids, 5,6,7,8,3′,4′‐hexamethoxyhomoflavone (1), 5,6,7,8,4′‐pentamethoxyhomoflavone (2) and 3,6,7,8,2′,5′‐hexamethoxyflavone (3) were isolated from the peels of mature fruits of Citrus unshiu Marcow (Rutaceae), together with the three known compounds 6,7,8,4′‐tetramethoxyflavone (=6,7,8‐trimethoxy‐2‐(4‐methoxyphenyl)‐4H‐1‐benzopyran‐4‐one), 3,5,7,8,2′,5′‐hexamethoxyflavone (=2‐(2,5‐dimethoxyphenyl)‐3,5,7,8‐tetramethoxy‐4H‐1‐benzopyran‐4‐one), and scopoletin (=7‐hydroxy‐6‐methoxy‐2H‐1‐benzopyran‐2‐one) of which the former two have never been isolated from natural resources, although they have been reported as synthetic compounds. The structures of 1–3 were elucidated on the basis of spectroscopic evidence, including 1D‐ and 2D‐NMR analysis.

Phytochemical investigation of the rhizomes of Gastrodia elata Blume (Orchidaceae) led to the isolation and identification of twelve compounds, including two new phenolic compounds, 4hydroxybenzyl vanillyl ether (¼ 4-{[(4-hydroxyphenyl)methoxy]methyl}-2-methoxyphenol; 1) and 4-{{4-[4-(methoxymethyl)phenoxy]benzyl}oxy}benzyl methyl ether (¼ 1-[4-(methoxymethyl)phenoxy]-4-{[4-(methoxymethyl)phenoxy]methyl}benzene; 2). The structures of 1 and 2 were elucidated by spectroscopic data analysis including 1D-and 2D-NMR experiments.