Antioxidant, Anti-Inflammatory, and Anti-Diabetic Activity of Phenolic Acids Fractions Obtained from Aerva lanata (L.) Juss.

Many plants that are commonly used in folk medicine have multidirectional biological properties confirmed by scientific research. One of them is Aerva lanata (L.) Juss. (F. Amaranthaceae). It is widely used, but there are very few scientific data about its chemical composition and pharmacological activity. The aim of the present study was to investigate the chemical composition of phenolic acid (PA)-rich fractions isolated from methanolic extracts of A. lanata (L.) Juss. herb using the liquid/liquid extraction method and their potential antioxidant, anti-inflammatory, and anti-diabetic properties. The free PA fraction (FA), the PA fraction (FB) released after acid hydrolysis, and the PA fraction (FC) obtained after alkaline hydrolysis were analysed using liquid chromatography/electrospray ionization triple quadrupole mass spectrometry (LC-ESI-MS/MS). The phenolic profile of each sample showed a high concentration of PAs and their presence in A. lanata (L.) Juss. herb mainly in bound states. Thirteen compounds were detected and quantified in all samples, including some PAs that had not been previously detected in this plant species. Bioactivity assays of all fractions revealed high 2,2-diphenyl-1-picrylhydrazyl (DPPH center dot) (2.85 mM Trolox equivalents (TE)/g) and 2,2-azino-bis-3(ethylbenzthiazoline-6-sulphonic acid) (ABTS(center dot+)) (2.88 mM TE/g) scavenging activity. Fraction FB definitely exhibited not only the highest antiradical activity but also the strongest xanthine oxidase (XO) (EC50 = 1.77 mg/mL) and lipoxygenase (LOX)(EC50 = 1.88 mg/mL) inhibitory potential. The fraction had the best anti-diabetic properties, i.e., mild inhibition of alpha-amylase (EC50 = 7.46 mg/mL) and strong inhibition of alpha-glucosidase (EC50 = 0.30 mg/mL). The activities of all analysed samples were strongly related to the presence of PA compounds and the total PA content.

Automated summary

This study investigated the chemical composition of phenolic acid-rich fractions isolated from Aerva lanata herb and found potential antioxidant, anti-inflammatory, and anti-diabetic properties. Fraction FB displayed the highest antiradical activity and inhibition of enzymes, particularly showing great anti-diabetic potential. The bioactivities were closely related to the presence of phenolic acid compounds and total phenolic acid content.