Antioxidant Activity of Some Plant Extracts Towards Xanthine Oxidase, Lipoxygenase and Tyrosinase

Abstract

Natural products have the potential to be developed into new drugs for the treatment of various diseases. The aim of the present study was to screen the antioxidant activities of some common edible fruits, garden plants and medicinal plants indigenous to Taiwan. This was performed by assessing the activities of lipoxygenase, xanthine oxidase and tyrosinase following incubation with extracts from these plants. A further aim was to use HPLC-DAD and tyrosinase to chromatographically identify the antioxidative constituents obtained from an extract exhibiting strong antioxidative properties. The acetone extracts of 27 cultivated plant species from Taiwan were tested for antioxidant activities towards xanthine oxidase, tyrosinase and lipoxygenase using spectrophotometric assays. Koelreuteria henryi, Prunus campanulata, and Rhodiola rosea showed the highest xanthine oxidase inhibitory activities. Camellia sinensis, Rhodiola rosea, and Koelreuteria henryi exhibited good tyrosinase inhibitory activities and potent anti-lipoxygenase activities. As Koelreuteria henryi had notable significant inhibitory activities towards xanthine oxidase, tyrosinase, and lipoxygenase, it was further tested with tyrosinase and HPLC-DAD. The results from this part of the study revealed that the more powerful the antioxidant capability of the extracted component, the greater the decrease in peak height obtained after reacting with tyrosinase. Additional studies are warranted to further characterize the compounds responsible for the antioxidant properties of the examined extracts.

Antioxidant Capacity and Lipophilic Constitution of Alternanthera bettzickiana Flower Extract

“…The acetone extract of A.bettzickiana has been recorded to possess lipoxygenase, tyrosinase and xanthine oxidase inhibitory activities 15 . Consequently, the fresh flowers of A.bettzickiana ( Fig.…”

“…3 and 4), that have been identified from the lipophilic fraction are tabulated (Table 2). Eighteen saturated [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] and four unsaturated [19][20][21][22] hydrocarbons, ten saturated [23][24][25][26][27][28][29][30][31][32] cholesterol homologues and it is reported that lowdoses of phytosterol-supplementation has produced significantly lowered plasma total cholesterol 22 . Such lipid-lowering effect of phytosterols is claimed to be mediated by competitive inhibition of cholesterol absorption and by transcriptional induction of genes implicated in cholesterol metabolism in both enterocytes and hepatocytes.…”

“…The whole plant is reported to be useful in purifying and nourishing blood and is claimed to be a soft laxative, a galactagogue and an antipyretic, in addition to its wound healing property. The acetone extract has been found to possess lipoxygenase, tyrosinase and xanthine oxidase inhibitory activities 15 . Earlier studies have reported the characterisation of simple and acylated betacyanins from the leaves 16 .…”

Effect of quercetin derivatives on melanogenesis stimulation of melanoma cells

“…Rhodiola rosea extracts was studied as melanogenesis suppressor. The acetone extract of R. rosea exhibits tyrosinase inhibitory activity [48]. Besides R. rosea root containing phenylethanol derivatives, phenylpropanoids, monoterpenes, flavonoids, phenolic acids, and triterpenes [49,50] decreases melanin content in B16 melanoma cells via suppressing the expressions of MC1R, a receptor of a-MSH, MITF, TRP-1, and tyrosianse [51].…”

Hepatoprotective effects ofFlagellaria indicaare mediated through the suppression of pro-inflammatory cytokines and oxidative stress markers in rats

“…Oxidative stress takes place in the human body when there is an upsurge in the amount of free radicals, or reactive oxygen species (ROS) that cannot be contained by our body's antioxidant defense system, therefore, leading to harmful diseases (Chin et al 2009). Normally, the human body has the ability to scavenge ROS using its naturally occurring antioxidant defense system and there is equilibrium between the ROS formation and dissipation.…”