Baicalein from Scutellaria baicalensis

Nishioka T, Kawabata J, Aoyama Y. (1998) Baicalein, an a-glucosidase inhibitor from Scutellaria baicalensis. J Nat Prod 61 1413-1415. 

Separation, purification and identification have yielded baicalein, baicalin and other Free-B-Ring flavonoids as the major active components in the organic extract from the roots of Scutellaria baicalensis, and S. orthocalyx. In Table 2, we demonstrated the potencies of five Free-B-Ring flavonoids isolated from three different Scutellaria species. 

Since ancient times, the roots of Scutellaria baicalensis have been used to treat allergic and inflammatory diseases in China and Japan. We reported the isolation from these roots of three new compounds, i.e., 2 S), 2, 5,6, 7-tetetahydroxy flavanone[25], 2 R), 3(i )-2, 3,5,6, 7-pentahydroxyflavanone and 2, 5,5, 7-tetrahydroxy-6, 8-dimethoxy-flavone, as antibacterial or anti-lipid peroxidation substances [26, 27], as well as six flavonoids, i.e., baicalein, bailcalin, oroxylin A, wogonin, skullcapflavone II, etc. Furthermore, we found that baicalein and baicalin "Fig. (47)" suppressed the development of secondary lesions in adjuvant-induced arthritis in rats "Fig. (48)". 

Fig. (48). Effects of baicalein and baicalin isolated from the roots of Scutellaria baicalensis on adjuvant-induced arthritis in rats.

Flavonoids such as baicalein from Scutellaria baicalensis and S. lateriflora inhibit pro-inflammatory metabolites including certain prostaglandins and leukotrienes. Quercetin and others are effective inhibitors of the release of histamine induced by various agents. They inhibit a number of stages of inflammation including granulation tissue formation in chronic arthritis (Middleton and Drzewiecki... 

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