Phytochemical and antioxidant analysis of the alcoholic extract of leaves, stem bark and roots of mangrove Avicennia marina from Gwater Bay

Marine plants are good source of natural antioxidant compounds. Mangroves are a group of salt-tolerant marine plants of intertidal areas with numerous medicinal properties. In the present study, phytochemical analysis (steroids, alkaloids, phenols, flavonoids and tannins) and antioxidant properties (total phenolic content, DPPH free radical scavenging activity, reduction power and metal chelating activity) of methanolic extract of leaves, stem bark, and roots of mangrove species Avicennia marina was investigated. The mangrove samples were collected from the shores of Gwater Bay in the southeast of Sistan and Baluchestan province. Phytochemical analysis showed that all the tested compounds were present in the extract of mangrove leaves, except alkaloids. While in the stem bark extract, only phenolic compounds, flavonoids and tannins were observed and alkaloids and steroids were not detected. Alkaloids, phenols and flavonoids were discovered in the root extract. The assessment of the antioxidant properties showed that among different parts of mangroves, the highest amount of phenol (6.28 mg gallic acid/ g extract), free radical scavenging (59.18 %) and iron ion reduction power (absorbance at 700 nm: 0.37) was found in the leaves extract. Contrary to these two indicators, the highest amount of iron chelating activity (absorbance at 562 nm: 0.84) was found in mangrove root extract. The results of this research showed that different parts of the mangrove plant, especially its leaves, can be considered as a potential source of natural antioxidants.