Chemical characterization and in vitro biological evaluation of aqueous extract of Althaea officinalis L. flower grown in Lebanon

Introduction: Herbal medicine is extensively used in various therapeutic strategies. Althaea officinalis L. of the family Malvaceae exhibits many biological activities through its phenolic acids, flavonoids, coumarins and polysaccharides. In Lebanon, the flowers are consumed in hot infusions. Therefore, the current study aimed to evaluate chemical and biological properties of Lebanese Althaea officinalis L. flower water extract.Methods: Chemical characterization was performed by qualitative phytochemical screening, gas chromatography-mass spectrometry (GC/MS) and liquid chromatography-mass spectrometry (LC-MS). Anti-proliferative effect was evaluated in cancer cells by MTT assay. The mRNA expression levels of pro-inflammatory enzyme and in-flammatory cytokines were assessed in LPS-stimulated RAW 264.7 cells. Cytoprotective activity was examined in red blood cells against hydrogen peroxide-induced hemolysis. Antioxidant property was assessed by DPPH radical scavenging assay.Results: Qualitative phytochemical screening of the extract revealed the presence of anthraquinones, flavonoids, lignins, phenols, tannins, terpenoids and others. GC/MS analysis suggested that most of the phytocompounds are conjugated to sugars rather than free. LC/MS analysis identified 5 phenolic acids (syringic, gallic, caffeic, p-coumaric and trans-ferulic acids) and 8 flavonoids (catechin, apigenin, chrysin, quercetin, kaempferol, genistein, rutin trihydrate and galangin). Biological evaluation of the extract showed anti-proliferative effects on A549, EB, HCT-116, MCF-7 and HeLa 229 cells, anti-inflammatory activity illustrated by decrease in mRNA expression of inducible nitric oxide synthase, interleukin 1 beta, tumor necrosis factor alpha and interleukin 6, cytoprotective activity in red blood cells and antioxidant property.Conclusion: Althaea officinalis flowers rich in phytocompounds exert interesting biological activities and hold promise in the pharmacological field.