Phenolic composition and antioxidant potential of different solvent extracts of the endemic Origanum elongatum (Bonnet) Emberger& Maire

Abstract

<jats:p>Plants of the Lamiaceae family are widely used for medicinal, cosmetic and culinary purposes. Phenolic compounds such as flavonoids and tannins are the main constituents of these plants; they have a proven multidirectional biological activity. Polyphenols have exceptional antioxidant potential, and they can intervene in the prevention of many health disorders. This work aims to study the composition and antioxidant power of phenolic compounds from crude extracts and fractions of Origanum elongatum leaves. This specie was subjected to phytochemical study through precipitation, turbidity and coloring reactions to highlight their secondary metabolites qualitative composition. Polyphenolic extraction was made by Soxhlet using two solvents: methanol 70%, ethanol 70%. Then, methanol’s crude was fractionated with solvents having escalating polarity; ethyl acetate, n-butanol. The polyphenols and flavonoids contents were spectrophotometrically estimated using Folin-Ciocalteau and Aluminum Trichloride methods. The antioxidant power of crude and fractionated extracts was evaluated by diphenyl-picryl-hydrazyl (DPPH●) and iron (FRAP) tests. The screening tests showed the existence of polyphenols, mucilages, sterols and triterpenes, oses and holosides. The highest yield of extraction is obtained by 70% methanol, with an average of 32.29%. Quantitative assays indicated that the hydroethanolic extract and the ethyl acetate fraction possessed high amount of polyphenols and flavonoids compared with other fractions and subsequently exhibited a marked scavenging activity on DPPH radical (IC50 = 0,085±0,002 and 0,112±0,003 mg/ml, respectively) and high reductive ability on ferric ion assay with IC50 = 0,181±0,004 mg/ml, 0,291±0,005 mg/ml, respectively.</jats:p>

Comparative Studies of the Phytochemical and Antioxidant activities of the leaves, stems, roots, and seeds extracts of Mitracarpus scaber Zucc (Rubiaceae)

“…These results are in agreement with those obtained by TLC. From Figure 3, it is seen that the antioxidant activity in the extracts is similar to those observed in vitamin C. In general, results of anti-radical activity using the spectrophotometer were in agreement with the assays of total polyphenols and total flavonoids 28 . In addition, our study revealed the behavior of DPPH on our hydromethanol extracts as a function of time.…”

“…These extracts were incubated at 3 minutes interval for 15 minutes. The different methods used are the FRAP method, the ORAC, and the radical DPPH • method 28 . The preference for the radical scavenging DPPH • method in the determination of antioxidant activity in compounds or extracts is due to its simplicity and ease of use, its speed, and the formation of a stable radical 29 .…”

Phytochemical Study and Antimicrobial Activity of Two Medicinal Plants from Al-Baha Region

“…On the other hand (Ramamurthy et al,; 2018) their results came in accord with result of this study 9 . (Tagnaout et al, 2016). Studied the chemical constituents of Capparis spinosa leaf extracts in different solvents 6 .…”

“…(Tagnaout et al, 2016). Studied the chemical constituents of Capparis spinosa leaf extracts in different solvents 6 . The results obtained by them were considerably different from what we found.…”

“…Ingredients present are alkaloids, fatty acids, phenolic acids, flavonoids, aldehydes, esters, vitamins and glucosinolates. Other studies by Ali-Shtayeh & Abu-Ghdeib (1999) established that the water extract of Capparis spinosa has antifungal characteristics together with a percentage of suppression greater than 90% against T. violaceum which in charge of ringworm and which is wide difuce in Africa and Asia 6 .…”