Optimization of the extraction process of Moringa oleifera flower by using Deep Eutectic Solvents (DES)

[Display omitted] •Deep Eutectic Solvents (DESs) are non-toxic solvents, also named as green solvents.•Combination of a hydrogen bond donor and a hydrogen bond acceptor tend to lower the melting point of DESs, which is termed as Eutectic point.•DESs enhance the extraction yield of phytochemicals.•DESs possess high viscosity so water is added to reduce the viscosity of the solvents.•Density of DESs depends on the molecular bonding and is affected by the interstitial spaces/voids in the molecules. Moringa oleifera is a plant native to India and its flowers are an excellent source of phenols, flavonoids, and antioxidants. DES (Deep Eutectic Solvents) based solvents have a vast majority of benefits, such as they are non-toxic, green solvents, with a highly efficient method of extraction of phenolic, antioxidant, and flavonoid compounds. DES solvents are made by combining two solvents, out of which one must be a hydrogen bond donor (HBD) and another must be a hydrogen bond acceptor (HBA) whereas, combining these two types reduces the melting point of the solvents. Six different types of DESs combinations were used in different ratios, for the optimization of the extraction process. The six combinations used were ChCl-Gly, ChCl-MA, ChCl-LA, ChCl-Glu, Pro-Gly, and Pro-LA. Total phenolic content, flavonoid content, antioxidant activity, lipase activity and glucose uptake assay of Moringa oleifera flower (MOFs) extracts were calculated in vitro at different temperatures ranging from 50 to 80 ℃ by using the statistical tool Anova single factor. Maximum yield, of phytochemicals were found at 70 ℃ with the DES combination Pro-Gly in 1:2 M ratio where phenolic content (32.4 mg GAE/g DW), Flavonoid content (42.1 mg QE/g DW), and antioxidant activity (65.82 %).