Characterization, Large-Scale HSCCC Separation and Neuroprotective Effects of Polyphenols from Moringa oleifera Leaves

Abstract

Moringa oleifera leaves have been widely used for the treatment of inflammation, diabetes, high blood pressure, and other diseases, due to being rich in polyphenols. The main objective of this work was to largely separate the main polyphenols from Moringa oleifera leaves using the technique of high-speed counter-current chromatography (HSCCC). The phenolic composition in Moringa oleifera leaves was first analyzed qualitatively and quantitatively by UPLC-Q-Exactive Orbitrap/MS and UPLC-QqQ/MS, respectively, indicating that quercetin and kaempferol derivatives, phenolic acid and apigenin are the main polyphenols in Moringa oleifera leaves, with quercetin and kaempferol derivatives predominating. Furthermore, the conditions of HSCCC for large-scale separation of polyphenols from Moringa oleifera leaves were optimized, which included the selection of the solvent system, flow rate and the sample load. Only by one-step HSCCC separation (within 120 min) under the optimized conditions, six quercetin and kaempferol derivatives, a phenolic acid and an apigenin could be individually isolated at a large scale (yield from 10% to 98%), each of which possessed high purity. Finally, the isolated polyphenols and phenolic extract from Moringa oleifera leaves (MLPE) were verified to have strong neuroprotective activities against H2O2-induced oxidative stress in PC-12 cells, suggesting that these compounds would contribute to the main beneficial effects of Moringa oleifera leaves.

Rapid Separation of Asiatic Acid, Quercetin, and Kaempferol from Traditional Chinese Medicine Centella asiatica (L.) Urban Using HSCCC-Semi-Prep-HPLC and the Assessment of Their Potential as Fatty Acid Synthase Inhibitors

“…Various factors were analyzed, including the rotation speed and the flow rate of the mobile phase. The flow rate of the mobile phase directly affects the amount of stationary phase fixed in the column, separation time, and peak resolution [ 29 , 32 ]. In this study, the effect of solvent systems at rotation speeds of 800 rpm/min, 900 rpm/min, and 1000 rpm/min on the retention of the target compound's stationary phase was investigated by comparing the retention of AA, QCN, and KPL in HSCCC.…”

An insight into the neuroprotective and anti-neuroinflammatory effects and mechanisms of Moringa oleifera

“…Quercetin is among the abundant flavonoids of M. oleifera (Vergara-jimenez, Almatrafi, & Fernandez, 2017). The leaves contain the highest quercetin, among other flavonoid compounds with four of the quercetin derivatives made up the majority of the flavonoids (Coppin et al, 2013;Zhu et al, 2020;Gao et al, 2022). Moreover, Makita et al (2016) and Lin et al (2018) have revealed that the quercetin present is in significant amounts as glycosides associated with a variety of sugar moieties.…”

“…The neuroprotective activities of astragalin are associated with the free radical scavenging ability and oxidative stress-induced influences on the brain neuronal cells ( Wasik and Antkiewicz-Michaluk, 2017 ; Riaz et al, 2018 ). Astragalin and isoquercitrin isolated from M. oleifera leaves showed potent anti-oxidative effects as enhanced cell viabilities were observed in H2O2-induced oxidative stress in PC-12 cells ( Gao et al, 2022 ). Although the associated active substances involved in the mechanism were not described, the study has found that the rate of survival for the damaged cells improved as the treatment concentration of isolated compounds increased, suggesting the effect of anti-oxidative activities.…”

Moringa oleifera Lam: A versatile medicinal tree in tropical and subtropical countries

“…Moringa can be used as a potent neuro-protectant by reducing the formation of ROS, thereby protecting the brain (Kirisattayakul et al, 2013). The isolated polyphenols and phenolic extract from moringa leaves have demonstrated strong neuroprotective activities against H2O2-induced oxidative stress in PC-12 cells (Gao et al, 2022). A cardioprotective alkaloid ( L-N,αrhamnopyranosyl vincosamide (VR), isolated from the leaves of markedly reduced isoproterenol (ISO)-M. oleifera, induced increase in the levels of serum cardiac markers (troponin-T, creatine kinase-MB, lactate dehydrogenase and glutamate pyruvate transaminase as well as cardiac lipid peroxidation) with a parallel increase in the antioxidants suggesting its cardio-protective and free radical scavenging potential (Panda et al, 2013).…”