Antimicrobial, antioxidant and phytochemical investigations of sea buckthorn (Hippophaë rhamnoides L.) organs

Hippophaë rhamnoides L. (Elaeagnaceae), commonly known as sea buckthorn, is a thorny bush with orange berries naturally distributed in Asia and Europe. Fruits of H. rhamnoides have been used by Chinese, Mongolian and Tibetan medicines for decades, and possessed considerable medicinal and nutritional values like antimicrobial, antitumoral, antioxidant and dermatological effects [1,2].

However the therapeutic potential and phytochemical diversity of the other H. rhamnoides parts remain unexplored. In this work we present the phytochemical and bio-activities screening of seed, leaf, stem and root of H. rhamnoides. The crude extracts were obtained by Pressurised Liquid Extraction (PLE) using ethanol. Each extract was then partitioned by liquid-liquid extraction using three solvents of different polarities: aqueous, ethyl acetate and hexane. The antimicrobial effect, the total phenolic content, the reducing power (FRAP), and the free radical scavenging activity (DPPH) of crude extracts and their fractions were evaluated. H. rhamnoides organs have all antibacterial values and that the most antioxidant potential was found in root and seed extracts. Furthermore, the antimicrobial and the antioxidant activities were found in the aqueous fraction. High Performance Thin Layer Chromatography (HPTLC) analyses of aqueous fractions showed that they were mainly constituted of sugar and polyphenolic compounds. The bio-activities were consequently attributed to the polyphenolic compounds present in active fractions of seed, leaf, stem and root of H. rhamnoides.

References: 1. Guliyev VB et al. (2004)J Chromatogr B 812: 291–307

2. Zeb A (2004)J Bio Sci 4: 687–693