Antioxidant Structure⁻Activity Relationship Analysis of Five Dihydrochalcones.
Xican LiBan ChenHong XieYuhua HeDewei ZhongDongfeng ChenPublished in: Molecules (Basel, Switzerland) (2018)
The study determined the comparative antioxidant capacities of five similar dihydrochalcones: phloretin, phloridzin, trilobatin, neohesperidin dihydrochalcone, and naringin dihydrochalcone. In the ferric-reducing antioxidant power (FRAP) assay, the antioxidant activities of pairs of dihydrochalcones had the following relationship: phloretin > phloridzin, phloretin > trilobatin, trilobatin > phloridzin, trilobatin > naringin dihydrochalcone, and neohesperidin dihydrochalcone > naringin dihydrochalcone. Similar relative antioxidant levels were also obtained from 1,1-diphenyl-2-picryl-hydrazl radical (DPPH•)-scavenging, 2,2′-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) (ABTS•⁺)-scavenging, and superoxide radical (•O₂−)-scavenging assays. Using ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC−ESI−Q−TOF−MS/MS) analysis for the reaction products with DPPH•, phloretin, phloridzin, and trilobatin were found to yield both dihydrochalcone-DPPH adduct and dihydrochalcone-dihydrochalcone dimer, whereas naringin dihydrochalcone gave a naringin dihydrochalcone-DPPH adduct, and neohesperidin dihydrochalcone gave a dimer. In conclusion, the five dihydrochalcones may undergo redox-based reactions (especially electron transfer (ET) and hydrogen atom transfer (HAT)), as well as radical adduct formation, to exert their antioxidant action. Methoxylation at the ortho-OH enhances the ET and HAT potential possibly via p-π conjugation, whereas the glycosylation of the ⁻OH group not only reduces the ET and HAT potential but also hinders the ability of radical adduct formation. The 2′,6′-di-OH moiety in dihydrochalcone possesses higher ET and HAT activities than the 2′,4′-di-OH moiety because of its resonance with the adjacent keto group.
Keyphrases
- tandem mass spectrometry
- liquid chromatography
- oxidative stress
- anti inflammatory
- mass spectrometry
- electron transfer
- simultaneous determination
- ultra high performance liquid chromatography
- ms ms
- high performance liquid chromatography
- multiple sclerosis
- high resolution
- high throughput
- pseudomonas aeruginosa
- cystic fibrosis
- staphylococcus aureus
- biofilm formation
- climate change