Analysis of Xanthine Oxidase Inhibitors from Clerodendranthus spicatus with Xanthine Oxidase Immobilized Silica Coated Fe3O4 Nanoparticles

Abstract

Abstract:In this study, xanthine oxidase immobilized silica coated Fe 3 O 4 nanoparticles (Fe 3 O 4 @SiO 2 -XO) were successfully prepared and characterized by transmission electron microscope, X-ray powder diffraction, Fourier transform infrared spectroscopy and vibrating sample magnetometer. The average diameter of the Fe 3 O 4 nanoparticles was about 300 nm to 350 nm with a shell thickness of 60 nm. The maximum saturation magnetization of the Fe 3 O 4 @SiO 2 -XO nanoparticles was 44.9 emu/g, which ensured the separation from the medium within one minute by using an ordinary magnet. A xanthine oxidase (XO) inhibitor screening method using Fe 3 O 4 @SiO 2 -XO nanoparticles was established and utilized in the extract of Clerodendranthus spicatus. Under the optimized conditions, two compounds were screened out and identified as gardenin B and eupatorin. The half maximal inhibitory concentration (IC 50 ) values of these two compounds were 1.488 µg/mL and 11.197 µg/mL, respectively. The interactions between these two compounds and XO were investigated by the fluorescence spectroscopic method. The results suggested that the quenching effects of gardenin B and eupatorin were due to a static quenching mechanism. Furthermore, gardenin B showed stronger binding capacity than that of eupatorin. In conclusion, this screening method exhibited efficiency and reusability in screening, identification and analysis of enzyme inhibitors from complex mixtures.

Advances in structures required of polyphenols for xanthine oxidase inhibition

“…Liu et al. (2018) isolated two compounds from extract of Clerodendranthus spicatus using XO‐immobilized silica‐coated Fe 3 O 4 nanoparticles and identified them as gardenin B and eupatorin (seen in Figure 2). Both of them possessed multiple methoxyl groups and showed potent XO inhibitory effects in vitro with IC 50 values of 1.488 and 11.197 μg/mL, respectively.…”

“…Liu et al. screened four XO inhibitors from Puerariae flos extract with centrifugal ultrafiltration coupled with HPLC‐MS, which were identified as tectoridin, daidzin, ononin, and biochanin A (Liu et al., 2018). Another three isoflavonoids, 2′‐hydroxygenistein, 3′‐methoxygenistein, and lupinalbin A, were isolated from the ethyl acetate fraction of Apios americana on the catalytic reaction mediated by XO (Kim & Jin, 2019).…”

“…Various bioactive compounds, including polyphenols, saponins, terpenoids, phenylethanoid glycosides, and alkaloids, have been reported to be effective XO inhibitors (Amessis-Ouchemoukh et al, 2017;Mehmood et al, 2019;Shi, Chen, Bao, Zeng, & Cai, 2019;Zhu et al, 2017). Among them, polyphenols have attracted most of the attentions from researchers because of their huge amounts and diverse biological activities such as antioxidation, antitumor, anti-inflammatory, antiviral, antihypertensive, hypoglycemic, and enzyme inhibitory effects Xie, Yang, Chen, & Xiao, 2014;Xie, Yang, Tang, Chen, & Ren, 2015;Zhao et al, 2018).…”

Screening and Evaluation of Xanthine Oxidase Inhibitors from Gnetum parvifolium in China

“…Gnetum parvifolium was extracted by microwave-assisted extraction method [23]. Twenty grams of samples were transferred into a conical flask containing 200 mL of 90% ethanol solution.…”

“Kidney Tea” and Its Bioactive Secondary Metabolites for Treatment of Gout

“…spicatus possesses diverse bioactive properties involving antioxidant, , anticancer, antiobesity, , anti-inflammatory, , diuretic, and nephroprotective ,,, effects. Nevertheless, according to a literature survey, there has been no report to pinpoint the secondary metabolites that might be responsible for anti-gouty properties of this plant. , We evaluated the effects of ethanol extract (EE) and its subfractions of C. spicatus on the treatment of gout, and the results showed that the ethyl acetate fraction (EAF) had potent anti-gouty arthritis, analgesic, and antihyperuricemic activities.…”