عنوان مقاله [English]
Introduction: Plants are potential sources of natural antioxidants and produce various antioxidative compounds to counteract reactive oxygen species. Consumption of plant derived antioxidant contributes to reducing risks of certain chronic and degenerative diseases. Echium amoenum also named as Gol-e-gavzaban in persian, is one of the most important species of Boraginaceae family and commonly found in the North of Iran. Echium amoenum is usually used as herbal tea in Iran for conditions such as common cold, bronchitis, sore throat, cough, stress and fatigue. The dried violet–blue petals of Iranian Borage also possess diaphoretic, diuretic, sedative, mood enhancer, antifebrile, laxative, anti-depressant, cardiotonic and blood rectifying properties. Recently, this plant is known as an effective factor against cancer. The present study was conducted at Islamic Azad University of Tehran Medical Sciences. The aim of the present study was to determine total phenolic and flavonoid compounds and antioxidant activity of various extracts of Echium amoenum from Kelardasht region.
Experimental: E. amoenum plants were collected from Kelardasht region in Mazandaran province, Iran (2020, June) at the flowering stage, identified by the herbarium of the Research Institute of Forest and Rangelands. The aerial of E. amoenum dried in shade at room for 6 days and ground to a fine powder. The plant sample (50 g) was extracted using Ethanol and Acetone solvents in different concentrations by maceration method. Afterward, the ethanolic and acetonic extracts of E. amoenum were filtered through Whatman No.1 filter paper. The ethanolic extract was evaporated to dryness under reduce pressure (rotary evaporator Buchi R-300, Switzerland) and acetonic extract was concentrated by vaccum oven (Memmert VO49, Germany) at 35°C. Then the extracts were dried by freeze dryer (UO11, Iran) at -40°C and were pulverized. In this study, extraction of total phenolic compounds from E. amoenum by Acetone and Ethanol solvents in three different concentrations (pure, 50% and 75%) were investigated. Total phenolic contents were determined by Folin- Ciocaltue assay and were expressed as mg of gallic acid per g of extract. Then the antioxidant capacity of extracts were assessed by DPPH radical-scavenging activity and reducing power assay and compared with BHT and ascorbic acid standards
Results and Disscussion: In all extracts, the highest total phenolic contents were observed in 50 percentage concentration so that in these conditions, total phenolic contents of acetonic and ethanolic extracts were obtained as 82.9 and 77.3 mg gallic acid equivalents (GAE)/g extract, respectively, ( p ≤ 0.05). Extracts showed antioxidant activity in a dose-dependent manner. Acetonic extract had more antioxidant activity and DPPH radical-scavenging than ethanolic exrtact. The increase antioxidant activity of the plant can be attributed to the high amounts of phenolic and flavonoid compounds.
Extension: Echium amoenum can be used as a potential source of phenolic compounds and natural antioxidant. According to the obtained results based on the high antioxidant properties of this plant, it is suggested that with more researches on extract of E. amoenum can be used more and more in the food industry to prevent the oxidative deteriorative activity of food materials.