Tawornchat Parichat, Pattarakankul Thitiporn, Palaga Tanapat, Intasanta Varol, Wanichwecharungruang Supason
Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
Center of Excellence on Petrochemical and Materials Technology, Chulalongkorn University, Bangkok 10330, Thailand.
ACS Omega. 2021 Jan 19;6(4):2846-2855. doi: 10.1021/acsomega.0c05142. eCollection 2021 Feb 2.
Luteolin is an anti-inflammatory flavonoid commonly found in many edible plants. The compound is popularly consumed as a supplement regardless of its poor water solubility (27.8 μg/mL at 25 °C) and low bioavailability. Here, mild one-pot polymerization of luteolin into water-dispersible nanospheres, with an average dry size of 234.8 ± 101.6 nm, an aqueous size distribution of 379.1 ± 220.5 nm (PDI = 0.338), an average ζ-potential of -36.2 ± 0.2 mV, and an 89.3 ± 4.8% yield, is described. The nanospheres consist of polymerized luteolin (polyluteolin) with a weight-average molecular mass of around 410000 Da. The chemical structure of polyluteolin is identified through H-H correlated spectroscopy (COSY), H-C heteronuclear single-quantum coherence (HSQC), and H-C heteronuclear multiple-bond correlation (HMBC) NMR spectroscopic analyses of the oligomers, and a polymerization mechanism is proposed. Unlike luteolin that showed both dose-dependent anti-inflammatory activity and cytotoxicity when tested in lipopolysaccharide-stimulated macrophages, the polyluteolin nanoparticles possess dose-dependent anti-inflammatory activity without causing cell death even at high concentrations.
木犀草素是一种常见于许多可食用植物中的抗炎类黄酮。尽管其水溶性较差（25℃时为27.8μg/mL）且生物利用度较低，但该化合物作为补充剂被广泛食用。本文描述了一种温和的一锅法将木犀草素聚合成水分散性纳米球的方法，纳米球平均干尺寸为234.8±101.6nm，水相尺寸分布为379.1±220.5nm（多分散指数PDI=0.338），平均ζ电位为-36.2±0.2mV，产率为89.3±4.8%。纳米球由聚合木犀草素（聚木犀草素）组成，重均分子量约为410000Da。通过对低聚物进行氢-氢相关光谱（COSY）、氢-碳异核单量子相干（HSQC）和氢-碳异核多键相关（HMBC）核磁共振光谱分析确定了聚木犀草素的化学结构，并提出了聚合机理。与在脂多糖刺激的巨噬细胞中测试时显示出剂量依赖性抗炎活性和细胞毒性的木犀草素不同，聚木犀草素纳米颗粒具有剂量依赖性抗炎活性，即使在高浓度下也不会导致细胞死亡。
