International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 07 Issue: 05 | May 2020 www.irjet.net p-ISSN: 2395-0072 © 2020, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 1 AN APPRAISAL ON ANTIMICROBIAL APPLICABILITY OF MARINE MACROALGAE Dr. Ankita Jain 1 , Nikunj B. Patel 2 , Varsha Tailor 3 , Smit Sathvara 4, Haresh S. Kalasariya 5 * 2,4,5* Smt. S. S. Patel Nootan Science & Commerce College, Sankalchand Patel University, Visnagar-384 315 1,3 Bhagwan Mahavir College of Science and Technology Bhagwan Mahavir University, Surat-395007 2 niks17micro@gmail.com, 3 Varshtailor96@gmail.com, 4 smitkadia3020@gmail.com, 1 jain.aim2009@gmail.com, * hareshahir22@gmail.com ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract - Algae are a very diverse group of autotrophic organisms that exist as unicellular as well as multicellular forms. The most complex marine plants are called seaweeds. Seaweeds are known for their various therapeutic properties. The term seaweeds refer only to macro or large marine algae, found as wild and cultivated, growing in saltwater. Seaweed produces metabolites that help in the protection against different biotic and abiotic stresses. These compounds show antiviral, antiprotozoal, antifungal, and antibacterial properties. Secondary metabolites from natural resources are a potential source of antimicrobial leads and drugs can be exploited to combat antimicrobial resistance in microorganisms. Seaweeds are a valuable medicinal source with a broad spectrum of biological activities. The substances isolated from Chlorophyta, Phaeophyta, and Rhodophyta show potent antimicrobial activity mainly belong to polysaccharides, fatty acids, phlorotannins, pigments, lectins, alkaloids, terpenoids, and halogenated compounds. In recent years, biological activities, potential health benefits, and the nutraceutical value of marine algae have been in great interest. Marine algae derivatives have shown potent sources for the novel, antibacterial drug discovery. This review, however, focuses specifically on the antimicrobial aspects of marine algae. Key Words: Macroalgae, Antimicrobial, Phycocompounds, Antibacterial, Seaweed 1.INTRODUCTION Algae are one of the primary producers and it is the division of lower plants that contain chlorophyll in plant cell organelle chloroplast. They can be divided broadly into two different types: macro-algae (macroscopic) and microalgae (microscopic).[1] Marine algae is a broad term of marine life in which, together with cyanobacteria, it forms the main primary producers at the base of the ocean food chain. Marine algae include invisible and unicellular microalgae, which together with cyanobacteria from the ocean phytoplankton, as well as, more visible and complex multicellular macroalgae commonly called seaweed. Seaweeds are found along with coastal areas, living on the floor of continental shelves and washed up in intertidal zones. The term seaweed refers to the macrophytic marine algae that grow exclusively in the shallow waters. They provide shelter and food for many different sea animals, lend beauty to the underwater landscape, and are a direct source of food and feed. It has been reported that seaweeds serve as an important source of bioactive natural substances.[2]Many metabolites isolated from marine algae are found to be bioactive.[3]They absorb the nutrients from the surrounding water and don’t need roots or any complex conducting tissues. Some large seaweed such as the kelps have root-like parts called holdfasts, not for conduction of water but to attach them to the rock. Most seaweed has to be attached to something to survive, and only a few will grow while drifting loose in the sea.[4]Three types of seaweeds are recognized, according to their pigments that absorb light of particular wavelengths and give them their characteristic colors of green (Chlorophyta), brown (Phaeophyta),or red (Rhodophyta). Because they need light to survive, seaweeds are found only in the relatively shallow parts of the oceans, which means around the shores. The seaweeds are distributed horizontally in different zonations viz. supratidal (supralittoral), intertidal (littoral), and subtidal (sublittoral) regions of the seas and oceans.[5]Seaweeds found in the intertidal, shallow, and deep waters of the sea up, to 180 m depth and in estuaries and backwaters. They grow on substrates like rocks, corals, stones, pebbles, and also as epiphytes on sea grasses. Many species of