Contribution à l’étude des options de valorisation de l’espèce Arbutus unedo L. dans l’ouest algérien.

Abstract

Arbutus unedo L., commonly known as Strawberry tree is a species known for its ecological and economic importance throughout its range, particularly in Algeria. It is of great interest in the maintenance of biodiversity, so that its preservation is required acutely now. However, it is rich in active ingredients and natural substances giving it so therapeutic value, should be studied and valued, featuring its phytochemicals, and identifying their chemical profiles and antioxidant activities. This study helps to highlight his ethnobotanical interest and industrial interest, and therefore we suggest domestication and culture as an industrial culture. In this context, this work contributes to the valorisation of the species Arbutus unedo L, an ericaceous in West Algerian. And this at traves: -An ethnobotanical investigation using a semi-structured questionnaire to determine the different medicinal uses of this plant. The investigation has shown that it is used in the treatment of painful and inflammatory conditions, diseases of the circulatory system and skin infections. -By addition, a phytochemical study was also initiated. In determining the quantitative determination of total phenolics and flavonoids extracts from four different solvents (1-butanol, ethyl acetate, chloroform, water), of Arbutus unedo L. fruit that grows naturally in three regions in western Algeria, the region of El Marsa (province of Chlef) the Terni region (province of Tlemcen) and Jebel Guezoul (province of Tiaret). The methodology for the quantitative assessment of these compounds is the method of colorimetry and Folin Ciocalteu procedure. The results revealed that the most significant amount of phenolic compounds was recorded in the ethyl acetate fraction extracted from native fruits of El Marsa, followed by that of Terni. The results show that the flavonoid compounds of ethyl acetate fraction of El Marsa gives the most remarkable values (56.84 mg CE/g dp) compared to other fractions which record values of the order of 2.18-56.84 EC mg /g dp. However, a characterization of phenolic molecules in the extracts of the fruit of the strawberry tree, a native of Tiaret region and El Marsa by chromatography method using high performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR) has was undertaken, respectively, to identify the qualitative content of these phenolic acids. Five flavonoid compounds have been identified in the area of Tiaret; which are: catechin, apiginine, silybin, naringin and fisetin. In additionthe characterization of the chemical profile of flavonoids of Arbutus unedo L. from El Marsa was performed by the method of nuclear magnetic resonance, and which revealed that two molecules identified are: 2’,5-dihydroxy-3’-methoxyflavone-7-O-β-D-glucopyranoside (flavonoïd glycoside) and 5-deoxysigmoidin B-4′-methyl ether (flavanone). The valorisation of our species Arbutus unedo L. is completed by the determination of the antioxidant capacity of four extracts in vitro, using the DPPH method. Of all the extracts, the ethyl acetate fraction extracted from fruit native of El Marsa (province of Chlef) showed the highest antioxidant activity, followed by that of the Jebel Guezoul (wilaya of Tiaret). Therefore, the results of the phytochemical study of the fruit of the strawberry tree native to western Algeria and its DPPH antioxidant determined by the test activity have shown clearly the phytochemical and biological potential of the forest species Arbutus unedo.L and could justify their use in traditional medicine. In the end, a statistical study was started to showcase the results of this study. This analysis allows to highlight the correlation characteristics of the study areas and polyphenols of fruits of Arbutus unedo L.