Chemical composition, antimicrobial and antioxidant activities data of three plants from Tunisia region: Erodium glaucophyllum, Erodium hirtum and Erodium guttatum

In the present work, phytochemical contents (total phenolic content, total flavonoids, and condensed tannins), antioxidant potentials, and antimicrobial activities of three plants in the Mediterranean genus Erodium (Erodium glaucophyllum, Erodium hirtum, and Erodium guttatum) from the Tunisia region were analyzed. The results showed that E. glaucophyllum contained high levels of polyphenols, flavonoids, and tannins. Therefore, E. glaucophyllum possesses high antioxidant activities (2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power scavenging activities), and high inhibition of linoleic acid oxidation. All three plants exhibited high antimicrobial activities. This study highlights tree plants’ importance as dietary sources for natural antioxidants can be used in traditional medicine and the pharmaceutical industry.


a b s t r a c t
In the present work, phytochemical contents (total phenolic content, total flavonoids, and condensed tannins), antioxidant potentials, and antimicrobial activities of three plants in the Mediterranean genus Erodium (Erodium glaucophyllum, Erodium hirtum, and Erodium guttatum) from the Tunisia region were analyzed. The results showed that E. glaucophyllum contained high levels of polyphenols, flavonoids, and tannins. Therefore, E. glaucophyllum possesses high antioxidant activities (2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power scavenging activities), and high inhibition of linoleic acid oxidation. Determination of the phytochemical content, total phenolic compounds, total flavonoids, and condensed tannins.
Evaluation of the antioxidant power and antimicrobial activity of the three plants.
Results have also important role sources of natural antioxidants, and might be appropriate for the development of reliable index to estimate tuber richness with bioactive molecules. Table 1 showed that the three plants contained high levels of polyphenols: 12476 mg GAE/ml, 18074.02 mg GAE/ml and 248.0872 mg GAE/ml for Erodium guttatum, Erodium hirtum and Erodium glaucophyllum, respectively. In addition the plant showed high levels of flavonoids with E. glaucophyllum being the richest one (91.9771.56 mg RE/ml). Concerning the levels of tannins they were 2070.5 mg TA/ml, 4271.3 mg TA/ml and 31.8770.38 mg TA/ml, for E. guttatum, E. hirtum and E. glaucophyllum, respectively. In parallel, antioxidant activities of the plants were investigated namely radical DPPH scavenging activities, the reducing power and inhibition of the peroxidation of linoleic acid. Furthermore, the E. glaucophyllum process high antioxidant activity (Table 1). Table 1 Reducing power, DPPH radical scavenging activity, and inhibition of the peroxidation of linoleic acid activity.

Extracts
Total phenolics (mg GAE/g DR * ) In addition, the results ( Table 2) showed that the three plants exhibit high antimicrobial activity. Furthermore, the E. guttatum possess high antimicrobial activity compared to E. glaucophyllum, and E. hirtum. These results show a high correlation between polyphenol content and antimicrobial activity. As a potential drug, three plants needs to be explored properly following bioactivity-directed fractionation in order to isolate bioactive constituents and to evaluate its therapeutic effects.

Material
The tuber of the three plants of E. glaucophyllum, E. hirtum and E. guttatum were collected from Jebel Orbata National Park-Gafsa-Tunisia regions. Fifty grams of leaf powder is extracted by maceration in a volume of 400 ml of a water-methanol solution (50%, v/v), for 24 h and with continuous stirring. All strains were obtained from Laboratory of Extremophile plants, Center of Biotechnology at the Ecopark of Borj-cédria. Hammam-Lif. Tunisia.

Determination of total phenolic content
The total polyphenols phenolic compounds were determined according to the method [1]. The results were expressed as gallic acid equivalents (mg GAE/g DR).

Determination of total flavonoid content
The level of flavonoids is determined based on the capacity of formation of a yellow flavonoidaluminum complex whose maximum absorbance is at 510 nm [2]. The amount of total flavonoid was reported as rutin equivalents (mg RE/g DR).

Condensed tannins contents
The determination of the condensed tannins in the different extracts is carried out according to the method of Broadhurst and Jones [3], modified by Heimler et al. [4]. Condensed tannins were expressed in milligrams of catechin equivalent per gram of extract (mg CE/g DR).

Antioxidant activity
The antioxidant activities were measured by different tests; the scavenging activity on DPPH radical of extracts was estimated as reported by Okawa et al. [5]. The reducing power of the extracts was determined according to the method reported by Choi et al. [6]. The peroxidation of linoleic acid was determined according to the method of Tlili et al. [7].

Antimicrobial activity
The antimicrobial activity of the extracts was determined by the diffusion method in agar medium cited by Oyaizu [8] and Celiktas et al. [9] with a slight modification, this method was employed to determine inhibition diameter of the extract against 6 g negative and gram positive strains.