Phytochemical Investigations And Biological Activities Of Cultured Spirulina Fusiformis Isolated From Lake Chitu, Ethiopia.

Abstract

Now Days A Wide Variety Of Secondary Metabolites Has Been Isolated From Terrestrial Plants However, Unexplored Natural Sources Of Bioactive Ingredients From Marine Are Gaining Much Attention Since They Can Lead To The Discovery Of New Compounds Or Bioactivities. Microalgae Have Been Proposed As An Interesting, Almost Unlimited, Natural Source In The Search For Novel Natural Functional Ingredients, And Several Works Have Shown The Possibility To Find Bioactive Compounds In These Organisms. Among The Micro Algae Spirulina Are Blue-Green Alga That Exists As A Single Celled Organism That Converts Sunlight Into Energy. This Study Investigated The Indoor Cultivation Of Spirulina, Followed By Isolation And Characterization Of Bioactive Compounds With Antibacterial, Antioxidant, And Sun Protection Potential. The Indoor Cultivation Of Spirulina Was Done Using Appropriate Media (Zarrouk Media) And Growth Condition Such As Ph., Light, And Aerator. While Indoor Cultivation Minimized Contamination Risks, Maintaining Temperature And Light Within The Ideal Range Presented A Significant Challenge. Total Extraction Was Done By Using Methanol And Fractionated Successively With Petroleum Ether, Dichloromethane Ethyl Acetate And Butanol By Liquid Extraction. Tlc Analysis Guided Further Separation Of The Extracts, Leading To Dichloromethane Being Chosen For Subsequent Column Chromatography Based On Its Promising Profile Which Led To The Isolation Of Two Compounds Namely Stigmasterol And Astaxanthin Diester While Ethyl Acetate Extract Furnishes Hexadecenoic Acid. The Structures Of These Compounds Were Established Using Spectroscopic Methods 1h, 13c Nmr, And Ir Spectroscopy. Antibacterial Activity Was Tested Against Two Gram-Negative E. Coli (Atcc 25922), P Aeruginosa (Atcc 27825), And Two Gram- Positive Bacteria S. Aureus (Atcc 25923) And S. Pyogenes (Atcc 11778) At 25 Mg/Ml, 50mg/Ml, 100mg/Ml And 200mg/Ml Concentrations Using Agar Disc Diffusion Method. The Results Indicate Methanol Extract Of Spirulina Show The Strongest Antibacterial Activity. Methanol Extract Showed A Maximum Zone Of Inhibition (18??.33) On S. Aureus Bacteria At Concentration 200 Mg/Ml Compared To The Ciprofloxacin (16??.33) At A Concentration Of 10??G/Ml Followed By P. Aeruginosa, E. Coli And S. Pyogenes At Concentration 200mg/Ml. The Antioxidant Activity Of The Spirulinaextracts (Methanol And Water Extract) And Isolates (Stigmasterol And Diester Astaxanthin) Was Evaluated By Dpph Free Radical Using Concentrations 25, 50,100, 200??G/Ml. Their Ic50 Inhibition Was 3.248, 0.46, 12.19, And 3.14 Respectively. The Methanol Extract Of The Microalgae Spirulinainhibited The Dpph Radical By 66.66, 73.35, 76.4 And 79.5 At 25,50, 100 And 200 ??G/Ml Respectively On The Other Hand, Compound 36 Displayed % Inhibition Of 79.8, 79.9, 80.2,83.6 At 25,50, 100 And 200 ??G/Ml Respectively. In This Study The Sun Protection Potential Of Spirulinaextracts (Water And Methanol Crude) And Compound 37 Were Evaluated Using The In Vitro Method. Among The Tested Samples, Compound 37 Exhibits The Highest Spf Value, Which Is 17.49. This Study Successfully Isolated And Characterized Bioactive Compounds From Spirulina And Demonstrated Their Potential In Diverse Applications, Including Antibacterial, Antioxidant, And Sun Protection. The Findings Highlight The Exciting Possibilities Of Exploring Spirulina For Novel Natural Ingredients With Significant Health Benefits.