Neuraminidase (NA) is a glycoside hydrolase that has been proposed as a potential therapeutic target for influenza. Thus, the identification of compounds that modulate NA activity could be of great therapeutic importance. The aim of this study is to develop a drug discovery tool for the identification of novel modulators of NA from both compound libraries and natural plant extracts. NA was immobilized onto the surface of magnetic beads and the inherent catalytic activity of NA-functionalized magnetic beads was characterized. Based on the enzymatic activity (hydrolysis ratio), the inhibitory activities of 12 compounds from plant secondary metabolites were screened, and the desired anti-NA activities of flavonoids were certified. Ligand fishing with the immobilized enzyme was optimized using an artificial test mixture consisting of oseltamivir, lycorine and matrine prior to carrying out the proof-of-concept experiment with the crude extract of Flos Lonicerae . The combination of ligand fishing and HPLC-MS/MS identified luteolin-7- O -β-D-glucoside, luteolin, 3,5-di- O -caffeoylquinic acid and 3,4-di- O -caffeoylquinic acid as neuraminidase inhibitory ligands in Flos Lonicerae . This is the first report on the use of neuraminidase functionalized magnetic beads for the identification of active ligands from a botanical matrix, and it sets the basis for the de novo identification of NA modulators from complex biological mixtures.
Huaiju is one of the most famous and widely used Flos Chrysanthemi (FC) for medicinal purposes in China. Although various investigations aimed at phenolics extraction from other FC have been reported, a thorough optimization of the phenolics extraction conditions from Huaiju has not been achieved. This work applied the widely used response surface methodology (RSM) to investigate the effects of 3 independent variables including ethanol concentration (%), extraction time (min), and solvent-to-material ratio (mL/g) on the ultrasound-assisted extraction (UAE) of phenolics from FC. The data suggested the optimal UAE condition was an ethanol concentration of 75.3% and extraction time of 43.5 min, whereas the ratio of solvent to material has no significant effect. When the free radical scavenging ability was used as an indicator for a successful extraction, a similar optimal extraction was achieved with an ethanol concentration of 72.8%, extraction time of 44.3 min, and the ratio of solvent to material was 29.5 mL/g. Furthermore, a moderate correlation between the antioxidant activity of TP extract and the content of extracted phenolic compounds was observed. Moreover, a well consistent of the experimental values under optimal conditions with those predicted values suggests RSM successfully optimized the UAE conditions for phenolics extraction from FC. Practical Application The work of the research investigated the plant phenolics in Flos Chrysanthemi and antioxidant capacities. These results of this study can support the development of antioxidant additive and relative food.
Yueyuan Chen,Ningtao Zhao,Jingru Song,Xiaojie Yan,Xiaohua Jiang,Fenglai Lu,Min Zhang,Dianpeng Li
Starch-guest complexes are gaining popularity due to their low digestibility and unique physicochemical properties. In this study, kudzu starch (KS) was modified by complexing it with four food-medicine homology extracts (FMH) to form starch-guest complexes (KS-FMH). The assembly process involved pre-gelatinization, autoclaving, and ultrasonic treatment. Digestion and structural characterization of KS-FMH were investigated to assess their potential as low glycemic index (GI) foods. Following the complexation treatment, the KS-FMH exhibited a more favorable hydrolysis pattern compared to native KS, showing a lower hydrolysis rate and equilibrium concentration ( C ∞ ) ( p < 0.05). Moreover, the addition of FMH affected the structural properties of KS, possibly due to non-covalent interactions between KS and FMH. The morphology and distribution of phenolic guests in KS-FMH were determined using scanning electron microscopy, confocal laser scanning microscopy, and high-performance liquid chromatography. These analyses demonstrated the selective inclusion characteristics of FMH in complexation, confirming the formation of KS-FMH complexes. This study underscores the potential of FMH as functional additives for creating low-GI diets with KS, thus promoting their practical application in the food industry.
危险品化学品经营许可证（带存储）