Assessment of Antioxidant and Antifungal Capacity of Selected Drifted Brown Seaweeds.

Abstract

Seaweeds, also known as marine macroalgae, are renewable biological resources found worldwide and possess various secondary metabolites. This study evaluated the phytochemicals, antifungal, and antioxidant activity of locally, and mass number of available seaweeds. Selected seaweeds were extracted using 70% methanol using heat methods. The GC-MS analysis of tested samples displayed, S. wightii and S. marginatum extracts present 13 and 4 bioactive complexes. In S. wightii the alkaloid compound 2,3-Dicyano-5,6-diphenylpyrazine was found to be high, and Silicic acid or dihydrogen tetroxide disilicate riches in S. marginatum. Tested both samples presented high potential to antifungal activity with range from 9 to 74 % and 6 to 74% for F. oxysporum and A. niger respectively. Moreover, F. oxysporum is highly sensitive ( = 74.66%, F_25,4 = 561.219, p = 0.004) to drifted S. marginatum. Minimum inhibitory concentration obeyed S. wightii 395.75 (IC₅₀), sufficient to inhibit 50% of F. oxysporum. In the DPPH method,, higher concentration of S. marginatum (­ = 70.95±1.12, F_25,4 = 449.853, p –0.005) and S. wightii (x̄ = 63.96 ± 1.12, F_25,4 = 397.90, p – 0.005) showed the significantly highest DPPH scavenging inhibition activity.  In the Phosphomolybdenum method, S. marginatum extract noted significantly top topmost inhibition activity (x̄ = 92.71±1.17, F_25,4 = 244.197, p – 0.003) while S. wightii exhibited slightly lower inhibition activity observed at (x̄ = 80.54±2.35, F_25,4 = 159.80, p – 0.003).  IC₅₀ value points to a higher antioxidant activity, IC₅₀ (287.64) value of S. wightii confirms that S. wightii has high antioxidant potential activity by total antioxidant assay methods when compared to S. marginatum. The present findings suggested that drifted seaweeds can be considered as a biological waste and used as a pharmacological activity.