Preliminary Phytochemical Screening, Proximate Analysis, Antioxidant and Antibacterial Activities of an Algal Species of Hydrodictyon Reticulatum

The freshwater algae grow in a wide range of aquatic habitats across the globe and are rich in secondary metabolites. The present study was designed to conduct the phytochemical screening, proximate analysis, antioxidant and antibacterial activities of water net (Hydrodictyon reticulatum), an algal weed from Pakistan. The pure and dried algal mass was crushed into a fine powder and four solvent-based extracts were used for phytochemical screening. The results of preliminary qualitative screening indicated the presence of flavonoids, phenols, quinones, steroids, resins, anthraquinones, glycosides, lignin, proteins, saponins, tannins, reducing sugars, alkaloids, terpenoids, fats, and oils, whereas the quantification results revealed the high quantities of total ash, crude proteins, crude fiber, alkaloids, carotenoids, flavonoids, and chlorophyll a. The studied methanolic extracts with maximum concentration (150 μg/ml) showed significantly (p-value ≤ 0.05) higher antioxidant and antibacterial activities. The IC50 values of the crude methanolic extract of water net were found very close to streptomycin (positive control) against both bacterial pathogenic species of Klebsiella pneumoniae and Staphylococcus aureus. This study concluded that the crude extracts of water net possessed antibacterial activity at par to streptomycin drug, and requires further detailed study for the separation, identification, and testing of the pure phytochemical compound to be used by the nutraceutical and or pharmaceutical industry.