Extraction, isolation, structure elucidation and evaluation of toxicity, anti-inflammatory and analgesic activityof Pituranthosscopariusconstituents from SEtif region

Abstract

ixABSTRACTPituranthos scopariusis a medicinal plant that is used in traditional medicine in Algeria and other North African nations to treat several diseases such as asthma, rheumatism, measles, dermatoses, jaundice, and digestive disorders. The present work aimed to investigate an ethnobotanical survey aboutPituranthos scopariusand assess the toxicity, anti-inflammatory (in vitro, andin vivo) potential,in vitroantioxidant,and analgesiceffects of stems and roots ofPituranthos scoparius. Furthermore;to isolate and elucidate the chemical constituents of then-butanol stem extract ofP. scoparius(ButE) and determine the toxicity and anti-inflammatory effects of these compounds added to the ButE. Data from an ethnopharmacological study showed that 24.47 % of people used this plant in folk medicine. Results obtained from the qualitative phytochemical analysis of stem extracts (SE), roots extracts (RE), and ButErevealed polyphenols, flavonoids, tannins, and free quinones in both SE, RE, and ButE, whereas alkaloids and coumarins were presentin the ButE.Quantitatively, our results showed that the most important highest amount of total polyphenols, flavonoids, and tannins contents were foundin ethyl acetate extract (EaE) of stems with 434.34 ± 2.75 μg gallic acid equivalent; 207.49 ± 1.03 μgquercetin equivalent, and 126.32 ± 1.32 μg tannic acid equivalent/ mg dried extract, respectively. Four compounds, identified as the rare isorhamnetin-3-O-β-apiofuranosyl (1→2)-βglucopyranoside, in addition to three well known compounds, namely isorhamnetin-3-O-β-glucoside, D-mannitol, and isorhamnetin-3-O-β-glucopyranosyl-(1→6)-β-glucopyranoside were isolated from ButE. These compounds were characterized by means of NMR and high-resolution mass spectral (HRMS) data. The crude extracts (CrEs) of stems and roots did not cause any deaths or changes in the behavior of treated animals; LD50values were found to be higher than 5 g/kg body wheight (BW). Results from thein vitrostudieshighlightgood antioxidant proprieties of different extracts from stems and roots in various models. The results from thein vitroanti-inflammatory activity showed that crude extracts, ButE, and the four compounds exhibited a significant level inhibitionof protein(p< 0.05) with dependent concentration (0.5, 1, and 2 mg/mL). Oral administration of CrEs at the doses of 100, 300, and 600 mg/kg produced a significant dose-dependent inhibition effect in both xylene and croton oil-induced ear edema in mice. Administration of CrEs at a dose of 100, 250, and 500 mg/kg significantly (p˂0.05) exhibited an anti-edematogenic effect in the carrageenan-induced rat paw edema after 3h. In the acetic acid-induced writhing model, CrEs significantly (p˂0.05) reduced writhing at a dose of 500 mg/kg. The topical anti-inflammatory effect showed that the four isolated compounds, as well as ButE, exhibit a significant (p< 0.05) dose-dependent (0.5 and 1 mg/ear) anti-inflammatory effect using croton oil-induced ear edema in mice. Results from in vitro cytotoxicity studies showed that the % lysis of the ButE, along with isolated compounds, was found to be virtually non-toxic. Through ethnomedicinal study, our findings prove the medicinal use ofP. scopariusin traditional medicine and as an additional source for natural anti-inflammatory agents.