Search

Herein, the anthocyanins from rose were extracted, purified and identified by ultrasound-assisted deep eutectic solvents (DES), the resin, and ESI-Q-TOF-MS, respectively. The purified anthocyanins were modified through acylation by means of enzymatic catalysis method to improve the stability of anthocyanins. Compared with traditional extraction agents (ethanol), anthocyanins extraction rate was significantly improved when choline chloride/lactic acid was chosen as extraction solvent, and reached 8.265 mg g−1. The ESI-Q-TOF-MS detection results showed that the main component of the anthocyanins was peonidin-3,5-di-O-glucoside with 65.93% content. Meanwhile, the maximal acylation rate was 95.13% under optimal conditions (0.25 g of anthocyanin, 2.5 mL of pyridine, 4 mL of methyl benzoate; 400 mg of Novocain 435 lipase addition; a water bath at 50 °C under negative pressure of 0.09 Mpa for 9 h). Furthermore, the loss rate of acylated anthocyanins was significantly lower than that of natural anthocyanins under the same temperature or light conditions, and the acylation of anthocyanin could significantly improve stability against temperature, light and pH. The acylated anthocyanin exhibited excellent free radical scavenging activities for DPPH and ABTS+, and IC 50 values (4.451 μg mL−1 for DPPH and 7.760 μg mL−1 for ABTS+) displayed its high antioxidant activity. • A sustainable DES-assisted sonication method for extracting anthocyanins from rose was developed. • The main component of the anthocyanins was peonidin-3,5-di-O-glucoside. • Τhe acylation of rose anthocyanin could improve stability against temperature, light and pH. • The acylated anthocyanin exhibited high antioxidant activity. [ABSTRACT FROM AUTHOR]

In this study, a novel three-dimensional zinc-based metal-organic framework (Zn-MOF), i.e., {Zn 2 (L) 2 (DMF) 2 H 2 O} n (L = 2,5-bis(phenylamino)-1,4-benzenedicarboxylic acid) was designed and developed under solvothermal condition. As a proof-of-principle, a π-conjugated framework of carboxylate ligand capable of “bottom up” synthesis was integrated with metal ion to construct a novel MOF for sensing applications. As expected, the synthesized Zn-MOF exhibited fluorescence enhancement for cadmium ion (Cd 2+ ) and sensing of nitrobenzene (NB) through fluorescence quenching. The detection limits were calculated to be 0.12 μM for Cd 2+ and 1.19 μg mL −1 for NB based on signal-to-noise ratio of 3:1. Moreover, various techniques and density functional theory investigations verified that the possible sensing mechanisms for Cd 2+ and NB included ion exchange and photoinduced electron transfer, respectively. Finally, their practical applications on real samples also demonstrated that the Zn-MOF-based sensor can be effectively utilized for detection and imaging of Cd 2+ present in the real water samples and living cells. This study may inspire future research and design of target fluorescent MOFs with specific functions. [ABSTRACT FROM AUTHOR]