Investigating the anti-inflammatory potential of Elaeagnus an-gustifolia L. through enzyme inhibition assays

Abstract

Elaeagnaceae family, which is common in the steppe regions of Asia, Europe, and North America, contains about 45 species, including three genus: Hippophae, Shepherdia, and Elaeagnus. There are two species in the genus Hippophae rhamnoides and Elaeagnus angustifolia. The species of the Elaeagnaceae family is widely used in public and traditional medicine due to its widespread prevalence in the world and in Turkey. Ethnobotanical field studies have revealed that the fruits of E. angustifolia L. are used in Anatolia as an anti-inflammatory, antipyretic, urolithiatic, antidiarrheal, and anti-inflammatory agent in eye infections. Furthermore, the fruit of this plant is consumed as an appetizer and a source of nutrition. The study aims to evaluate the in vitro anti-inflammatory activity of extracts in different polarities from the leaves, branches, and fruits of E. angustifolia and to establish the content of polyphenolic compounds (flavones and polyphenolic carboxylic acids) in the ethyl acetate extract branches using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS). In this context, the anti-inflammatory effects of n-hexane, ethyl acetate, and methanol extracts prepared from the plant have been evaluated through in vitro cyclooxygenase (COX-1 and COX-2) enzyme inhibition, inhibition of protein denaturation and proteinase enzyme, and anti-lipoxygenase activity tests. The results showed the highest activity of the ethyl acetate extract from branches. The HPLC-MS analysis revealed that the ethyl acetate extract prepared from the branches at a concentration of 100 mg/g contains p-coumaric acid (123.91 mg%), ferulic acid (62.07 mg%), kaempferol (43.11 mg%), sinapic acid (9.82 mg%), and quercetol (12.46 mg%). It was concluded that the data obtained in this context supported the use of the plant in folk medicine.