15-Lipoxygenase inhibition

Arachidonate 12-lipoxygenase inhibition. Essential oil of the unripe fruit was active on platelets, IC50 7 (Xg/mL Arachidonate 5-lipoxygenase inhibition. 

Misik, V., L. Bezakova, L. Malekova, and D. Kostalova. 1995. Lipoxygenase inhibition and antioxidant properties of protoberberine and aporphine alkaloids isolated from Mahonia aquifolium. Planta Med. 61 372-373. 

In addition to aconitases, nitric oxide is an inhibitor of many other enzymes such as ribonucleotide reductase [71], glutathione peroxidase [72,73], cytochrome c oxidase [74], NADPH oxidase [75], xanthine oxidase [76], and lipoxygenase [77] but not prostaglandin synthase [78]. (Mechanism of lipoxygenase inhibition by nitric oxide is considered in Chapter... 

Seven Artocarpus flavonoids and morusin (3) were tested for their inhibitory actions on arachidonate-5-lipoxygenase purified from porcine leukocyte [84]. As shown in Fig. (13), the IC50 values varied depending on the structural modification of the compound. The compounds having three hydroxyl groups at positions 2, 4, and 5 on the B ring (compounds 7, 8, 52 and 55) were more potent inhibitors. Thus, the vicinal diol partial structure was important for 5-lipoxygenase inhibition. 

These novel tetrameric bromotyrosine metabolites display a range of biological activities, including effects on calcium channels (1900), lipoxygenase inhibition (1772), tumor angiogenesis inhibition (1901), and endothelial cell anti-proliferation (1902). Syntheses of several bastadins have been accomplished (1903,1904). 

Rival, S.G., Boeriu, C.G., and Wichers, H.J. 2001a. Caseins and casein hydrolysates. 2. Antioxidative properties and relevance to lipoxygenase inhibition. J. Agric. Food Chem. 49, 295—302. 

Four protoberberine alkaloids and one aporphine alkaloid were evaluated for lipoxygenase inhibition. Oxyberberine and columbamine were the most potent lipoxygenase inhibitors tested, with jatrorrhizine being intermediate, whereas berberine and magnoflorine exhibited only low potencies. A strong linear correlation between lipoxygenase inhibition and lipid antioxidant properties of these alkaloids was observed. These data suggest that the mechanism of... 

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