Extraction and evaluation of antioxidant, anti-inflammatory and analgesic effects of Scabiosa atropurpurea L. extracts

Abstract

Scabiosa atropurpurea is a therapeutic herb growing in Algeria, and displayed a variety of biological effects due to its abundance on different secondary metabolites. This investigation focused on the determination of bioactive compounds and evaluation of the antioxidant, anti-inflammatory, anticancer capacities and the acute toxicity of the whole aerial part from S. atropurpurea. The extraction procedures conducted to obtain the aqueous (AqE) and methanolic (ME) extracts with yields of 9.06% and 13.8%, respectively. The initial phytochemical analysis confirmed the presence of polyphenols, terpenoids, flavonoids, saponins, tannins, anthraquinones, free quinones and reducing sugars in both extracts, whereas coumarins were absence in the ME. The quantitative analysis showed that ME exhibited the largest total polyphenols with 114.13 ± 0.92 μg gallic acid equivalent /mg dry extract and flavonoids with 100.57 ± 0.93 μg quercetin equivalent /mg dry extract. However, the important condensed tannins tenor was detected in AqE with 41.04 ± 0.64 μg catechin equivalent /mg dry extract. Furthermore, the UPLC-MS/MS analysis characterized 34 bioactive components in both extracts under negative and positive ion modes. The recognized compounds primarily included phenolic acids and flavonoids, followed by triterpenoids, sesquiterpenoids, tannins, saponins, iridoids, fatty acids, and others. The tested extracts presented in vitro antioxidant capabilities through different protocols (DPPH and hydroxyl radicals scavenging effects, ferrous iron chelating, reducing power and phosphomolybdate assay). The anti-inflammatory potential was assessed in vitro using protein denaturation reduction model and both extracts exhibited a dose related potential. The findings from the in vivo anti-inflammatory activity highlighted a significant reduction in ear and hind paw edematous in dose dependent manner.