Antioxidant activity of different extracts of lotus (Nelumbo nuficera Gaertn) rhizome by gradient solvent extraction

Abstract

In vitro antioxidant activity of extracts of lotus rhizome with different solvent by gradient extraction was determined. The extraction yield and total phenolic content of extracts were determined. 1,1-diphenyl-2-picrylhydrazyl hydrate (DPPH) radical scavenging assay and β-carotene-linoleic acid assay were conducted to assess the antioxidant activity of the extracts. Results showed that the yield of butanol extract was the highest. The order of total phenolic content in different extracts was as follows: water extract < petroleum ether extract < chloroform extract < butanol extract < ethyl acetate extract, the same with that of the DPPH scavenging activity. The total phenolic content was significantly correlated with DPPH scavenging activity (R 2 = 0.9363). All extracts, except water extract with too poor antioxidant activity, showed obvious antioxidant activity against β-carotene-linoleic acid, and the antioxidant activity of butanol extract was significantly lower than others. There was no significant correlation between the antioxidant activity against β-carotene-linoleic acid and the total phenolic content (R 2 =0.1995).

Study on the formation mechanism of blackening in damaged lotus rhizome epidermis: Effects of polyphenols and iron

“…This was in high consistency with the results of Yi et al (2016), which detected eight phenolic substances in the epidermal of "Elian 5," both of which detected gallocatechin, catechol, catechin, and epicatechin, but the latter of the remaining three substances was not detected, and the former did not detect gallic acid, p-coumaric acid, caffeic acid, and rutin. The reasons for these differences may be related to the phenological period of lotus rhizome, the extraction method of phenolic substances, and the elution method of HPLC (Ren & Yang, 2022;Vannuchi et al, 2021). Moreover, compared with the BT group, the formation of blackening in LRE (MT group) caused a significant decrease (the larger reduction in gallocatechin, dopa, and catechin contents) in the content of seven kinds of polyphenols (p < 0.05), which was consistent with the change in TPCs (Figure 1f).…”

Optimization of extraction technology of alkaloids in lotus leaf based on BP neural network

“…As a kind of homologous food and medicine, lotus leaf contains multiple chemical components in common plants such as carbohydrates, lipids, tannins (Huang et al, 2017;Liu et al, 2016), but also contains more than 20 alkaloids include lotus alkaloid, N-dimethyl lotus leaf alkaloid, Asiatic papaverine and so on (Pan et al, 2019;Ren & Yang, 2022). Lotus leaf alkaloid not only has the effect of blood circulation, lowering blood fat and losing weight, lowering blood pressure, present arteriosclerosis (Li et al, 2011;Wang, 2012), and antiviral, but also has the effect of anti-mitotic and strong bacteriostatic (Wang et al, 2011;Yan et al, 2022a).…”