ORIGINAL ARTICLE 1128 P J M H S VOL. 7 NO.4 OCT – DEC 2013 Comparative Analysis of Antioxidant Potential of Sargassum Sp and Lyengaria Sp GHAZALA BUTT 1 , EJAZ HUSSAIN 1 , ABDUR REHMAN 2 ABSTRACT Aim: To evaluate wide ranging bioactive ingredients using in-vitro assays for a better understanding of the protein networks which are targeted by natural agents. Methods: Sargassum sp and Iyengaria sp were collected from southeast coast of Karachi. The powdered seaweed samples (500 g of Sargassum sp and Iyengaria sp) were extracted with methanol in conical flasks at room temperature for three weeks. The samples were filtered using Whatman filter paper to obtain clarified filtrates. ABTS radical scavenging assay and FRAP assays were used to analyze antioxidant potential. Results: The methanolic extract of Sargassum sp showed higher potential of antioxidant activity as evidenced by ABTS radical scavenging assay. Methanolic extract of Iyengaria sp show the highest FRAP value 26.5 mM, indicating to highest antioxidant potential as evidenced by FRAP assay. Conclusion: Identification of bioactive ingredients having considerable antioxidant potential will be helpful in better and deeper understanding of the underlying mechanisms inhibited or activated by natural agents to suppress carcinogenesis. Keywords: Antioxidant, sargassum Sp, Lyengaria Sp INTRODUCTION Increasingly it is being realized that due to off target effects of chemotherapeutic drugs, drug discovery from marine natural products has re-gained tremendous appreciation in past few years. Rapidly accumulating experimental evidence regarding considerable and encouraging results obtained from in-vitro studies set stage for an interdisciplinary research to identify drugs with substantial efficacy and lesser off target effects 1,2 . It is appropriate to mention that translation of some of marine derived compounds from bench-top to the bedside including Ziconotide a peptide originally discovered in a tropical cone snail for the treatment of pain and Trabectedin (first marine anticancer drug) has opened new horizons for the researchers. MATERIALS AND METHODS Algal Material: Seaweeds used in this study were Sargassum sp and Iyengaria sp. The seaweeds were collected during the winter season in the month of Feb. 2013, from, Sandspit, Hawkesbay, Buleji, Haji Goth and Paradise Point region on the southeast coast of Karachi Pakistan respectively. The seaweeds samples were dried, and powdered after washing thoroughly in fresh water to remove salt and ---------------------------------------------------------------------- 1 Department of Botany, GCU, Lahore, Pakistan. 2 Department of Radiology, Rashid Latif Medical College, Ferozepur Road, Lahore. Correspondence to Miss Ghazala Butt, Department of Botany, GCU, Lahore, Pakistan. drghazala71@yahoo.com other unwanted materials and stored in airtight containers at room temperature for further study. The powdered shad-dried seaweed samples (500 g of Sargassum sp and Iyengaria sp) were extracted with methanol in conical flasks (1500 ml) (Volumetric flasks, (Pyrex) 1000 cm3) respectively at room temperature for three weeks. Filtration and evaporation give rise to a dark green viscous oily mass (17.34 g and 19.08 g respectively) of methanolic crude extract. The methanolic crude extract (5 mg) was mixed with (1 ml) of methanol for antioxidant activity. ABTS radical cation decolourization assay ABTS assay can be used to determine the antioxidant efficacy of organic fluids, tissues, cells, synthetic and natural therapeutical compounds. Trolox was a water soluble form of vitamin E used for positive control for reducing the formation of radical cation in this assay. ABTS solution was prepared with mixing of 5 ml of 14 mM ABTS solution with 5 ml of 4.9 mM potassium per sulphate (K 2 S 2 O 8 ) solution. After that the mixture was left to stand in dark at room temperature for 16 h for suspension. The absorbance of the reagent was then adjusted to 0.700 ± 0.02 at 734 nm with deionized water and used for this assay. Ferric reducing antioxidant activity assay The FRAP test was inexpensive, simple, wild and vigorous assay which uses antioxidants as reluctant in a redox associated colorimetric method to test the total antioxidant potential directly. FRAP reagent was prepared by mixing the reagents such as: 0.1 Molar acetate buffer with pH 3.6, 10 mili Molar of (TPTZ)