Molecular Structure–Affinity Relationship of Flavonoids in Lotus Leaf (Nelumbo nucifera Gaertn.) on Binding to Human Serum Albumin and Bovine Serum Albumin by Spectroscopic Method

Abstract

Lotus leaf has gained growing popularity as an ingredient in herbal formulations due to its various activities. As main functional components of lotus leaf, the difference in structure of flavonoids affected their binding properties and activities. In this paper, the existence of 11 flavonoids in lotus leaf extract was confirmed by High Performance Liquid Chromatography (HPLC) analysis and 11 flavonoids showed various contents in lotus leaf. The interactions between lotus leaf extract and two kinds of serum albumins (human serum albumin (HSA) and bovine serum albumin (BSA)) were investigated by spectroscopic methods. Based on the fluorescence quenching, the interactions between these flavonoids and serum albumins were further checked in detail. The relationship between the molecular properties of flavonoids and their affinities for serum albumins were analyzed and compared. The hydroxylation on 3 and 3’ position increased the affinities for serum albumins. Moreover, both of the methylation on 3’ position of quercetin and the C2=C3 double bond of apigenin and quercetin decreased the affinities for HSA and BSA. The glycosylation lowered the affinities for HSA and BSA depending on the type of sugar moiety. It revealed that the hydrogen bond force played an important role in binding flavonoids to HSA and BSA.

The interaction of dietary flavonoids with xanthine oxidase in vitro: molecular property-binding affinity relationship aspects

“…The uorescence spectra of xanthine oxidase and the quenching effects of samples were performed according to procedures reported in previous literature. 27,28 Various volumes of samples (0-100 mL, 1.0 mmol L À1 in methanol) were mixed with 2.0 mL of…”

Biotransformations of Flavones and an Isoflavone (Daidzein) in Cultures of Entomopathogenic Filamentous Fungi

“…Flavones, unlike flavanones, have a double bond between C2 and C3. The presence of this bond provides the molecule with planarity and is of great importance for interaction with enzymes and the biological activity exhibited by the compounds [ 7 , 33 ].…”

Hydrophobics of CnTAB in an aqueous DMSO–BSA nanoemulsion for the monodispersion of flavonoids

“…In the past decade, many investigations have been carried out on the study of the spectroscopic interactions of avonoids with globular proteins and surfactants systems. [23][24][25][26][27] No adequate work had been reported in the literature that deals with the study of avonoids with BSA and surfactants mixtures [28][29][30] in the formation of dispersions at various temperatures.…”

“…The dipole moment value (Table S2 †) was calculated by using the reported equation. 23 This proton (3H + ) could further activate the destabilized H 2 O as:…”