Of luteolin

Fig. 2 The influence of the reagent concentration on the sensitivity of detection detection of equal amounts of luteolin with basic lead acetate solution that was (A) undiluted, (B) diluted 1 + 4 and (C) diluted 1 + 50.

Tenerife and La Palma, revealed the existence of luteolin and an array of simple phenolic derivatives as well as three known phytosterols, B-amyrin, sitosterol, and stigmasterol. The phenols identified comprised a set of phenylpropanoids myristicin [566] (see Fig. 6.16 for structures 566-573), methyleugenol [567], todadiol [568], todatriol [569], crocatone [570], elemicin [571], apiole [572], and the coumarin scopoletin [573]. The occurrence of these compounds is recorded in Table 6.5. The differences between the two profiles were taken by Gonzalez and his co-workers... 

Floiistics and Paleofloristics of Asia and Eastern North America. Elsevier, Amsterdam. Harborne, J. B. 1960. Luteolinidin, a 3-deoxyanthocyanin analogue of luteolin. Chem. Ind. (London) 130. 

The optimized RPLC UV-Vis ESI MS method for all typical blue colourants (indi-goids, hematein, tannins, anthocyanins and selected flavonoids) was used for the identification of dyes extracted from a thread taken from an Italian tapestry of unknown origin from the collection of the National Museum in Warsaw (Poland). It was found that to obtain the red-blue colour of the fibre a mixture of dyestuffs was probably used. The presence of indigotin, tannic and ellagic acid (at m/z 301, NI), as well as carminic acid, suggested the use of indigo and cochineal. Reseda luteola could also have been used due to the presence of luteolin and apigenin. 

Mareck, U. et al., The 6-C-chinovoside and 6-C-fucoside of luteolin from Passiflora edulis. Phytochemistry, 30, 3486, 1991. 

Shimoi, K., Okada, H., Furugori, M., Goda, T., Takase, S., Suzuki, M., Hara, Y., Yamamoto, H., and Kinae, N., Intestinal absorption of luteolin and luteolin 7-0- 3-glucoside in rats and humans, FEBS Lett., 438, 220, 1998. 

Substantial quantities of luteolin-7-O-glucuronide, luteolin-7-O-glucoside, and luteolin-7-O-rutinoside occur in Red Oak Leaf and Lollo Rosso, two red-leaved varieties of lettuce (Lactuca sativa) [Llorach et al., 2008], Polymethoxylated flavones such as nobiletin, scutellarein, sinensetin, and tangeretin (Fig. 1.8) are found exclusively in citrus species [Crozier et al., 2006c], while diosmetin-7-O-glucuronide has been isolated from the fruits of a Chinese herb, Luffa cylindrical. 

Kim TJ, Kim JH, Jin YR, Yun YP. 2006. The inhibitory effect and mechanism of luteolin 7-glucoside on rat aortic vascular smooth muscle cell proliferation. Arch Pharm Res 29 67-72. 

Figure 5.2 Structures of luteolin (L), kaempferol (K), and taxifolin (T). A comparison of the antioxidant (inhibition of MPO and radical scavenging activity) and anti-inflammatory (inhibition of LTB4) activity with that of quercetin (Q) is summarized.

Hydnocarpin (68) and hydnocarpin D (69) are regioisomers. While biomimetic radical coupling of luteolin (118) with 45 in the presence of Ag2C03 yielded 69 as a major product, coupling in the presence of horseradish peroxidase/H202 produced a good yield of hydnocarpin (68) 123) (Scheme 7). 

The antimicrobial activity of luteolin. Fig. (35), a flavonoid isolated from Wedelia paludosa was also evaluated [205]. The compound showed activity towards the dermatophytes Epidermophyton floccosum. Trichophyton rubrum and Trichophyton mentagrophytes. 

Fig. 14 (-)-Epicatechin (flavan-3-ol, 62), (-)-epigallocatechin (flavan-3-ol, 63), (+)-catechin (flavan-3-ol, 43) and (+)-gallocatechin (flavan-3-ol, 64) in leaves of tea (Camellia sinensis L.), and analogs of luteolin (flavone, 65) and isoorientin C-glycoside (flavone C-glycoside, 66) in angiosperms...

Lucenin-1 has the same ultraviolet absorption spectrum as that of luteolin and orientin, and shows the same diagnostic shifts it gives no sugar under conditions normal for the acid hydrolysis of glycosides, and... 

Two-dimensional chromatograms of Vitex lucens extracts show the presence of (a) four compounds, all of which are postulated to be 6,8-di-C-glycosyl derivatives of luteolin, differing only in the structure of the glycosyl groups, and (b) at least three compounds which are, similarly, di-C-glycosyl derivatives of apigenin. 

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