The In Vitro Antioxidant Activity and Inhibition of Intracellular Reactive Oxygen Species of Sweet Potato Leaf Polyphenols

Abstract

The in vitro antioxidant activity and inhibition of intracellular reactive oxygen species (ROS) of the total and individual phenolic compounds from Yuzi No. 7 sweet potato leaves were investigated in this study. Sweet potato leaf polyphenols possessed significantly higher antioxidant activity than ascorbic acid, tea polyphenols, and grape seed polyphenols. Among the individual phenolic compounds, caffeic acid showed the highest antioxidant activity, followed by monocaffeoylquinic acids and dicaffeoylquinic acids, while 3,4,5-tri-O-caffeoylquinic acid showed the lowest value. Sweet potato leaf polyphenols could significantly decrease the level of intracellular ROS in a dose-dependent manner. The order of the inhibiting effect of individual phenolic compounds on the intracellular ROS level was not in accordance with that of antioxidant activity, suggesting that there was no direct relationship between antioxidant activity and intracellular ROS-inhibiting effect. Sweet potato leaves could be a good source of biologically active polyphenols with multiple applications in the development of foods, health products, pharmaceuticals, and cosmetics.

Total Polyphenol Content, Antioxidant Activity, and Individual Phenolic Composition of Different Edible Parts of 4 Sweet Potato Cultivars

“…1 leaves (2109 ± 0.15 mg/100 g DW), and Shangshu 19 leaves (1855 ± 0.17 mg/100 g DW), with significant differences among them (Table 2, P < 0.05). Our findings were in agreement with those reported by Lu et al 25 and Sun et al 12 in SPL. Our results also showed differences in phenolic acid composition which might be attributed to the differences between cultivars, the state of maturity, genotype, and environmental conditions, resulting in different phenolic acid constituents (ie, mono-, di-, and tri-caffeoylquinic acids).…”

“…7 These variations are ascribed to differences in color, variety, and environmental and processing conditions. 12 Bioactive components described in sweet potato comprise phenolic acids, such as caffeic acid and caffeoylquinic acid derivatives, including mono-, di-and tri-caffeoylquinic acids 13 ; flavonoids, such as astragalin, quercetin, kaempferol, and myricitrin 14 ; and cyanidin or peonidin-type anthocyanins. 9,15 Zengin et al 16 investigated TPC in SPL and found a range of 73.10 ± 3.75 to 89.26 ± 1.34 gallic acid equivalents (GAE) mg/g extract.…”

Transcriptome Analysis Identified Coordinated Control of Key Pathways Regulating Cellular Physiology and Metabolism upon Aspergillus flavus Infection Resulting in Reduced Aflatoxin Production in Groundnut

“…Previously, it has been shown that the presence of these compounds could help in mitigating aflatoxin contamination in groundnut [ 55 ]. Likewise, genetic manipulation of crops to improve the flavonoids/anthocyanin/polyphenols content has been broadly used to enhance the antioxidant content and reduce susceptibility to diseases (biotic stress) including fungal diseases [ 56 , 57 , 58 , 59 ]. Furthermore, application of flavonoids/polyphenol can significantly reduce the growth of A. flavus and toxin production [ 55 , 60 , 61 ].…”

Influence of Green Leafy Vegetables in Diets with an Elevated ω-6:ω-3 Fatty Acid Ratio on Rat Blood Pressure, Plasma Lipids, Antioxidant Status and Markers of Inflammation

“…Although the current research study did not focus on the mechanisms whereby which the nutritional, chemical, antioxidant and bioactive compounds within the GLVs were able to mitigate the risks for CVD, several metabolic pathways may be initiated or suppressed that may to some extent offer insight to the observed findings. For example, reductions in oxidative stress, inflammation, blood pressure and improved endothelial function may be mediated by compounds such as nitrates [ 82 ], phytochemicals [ 83 ], flavonoids [ 84 ], polyphenols [ 85 ] and omega-3 fatty acids [ 86 ], which are commonly found in GLVs such as collard greens, purslane and sweet potato greens. While brown and white adipose tissue levels were not measured, research has demonstrated that these tissues play a vital role in lipid storage, endocrine function, adipokine concentrations and inflammation [ 87 ].…”