Ifakat Tulay Cagatay

Ifakat Tulay Cagatay

Akdeniz University, Turkey

Title: Antimicrobial activities of microalgea nannochloropsis oculata for fish pathogens


I completed my master degree in Microbiology at Hacettepe University, Ankara, Turkey, in 1997 and finished my PhD (Molecular Microbiology) at Lincoln University, New Zealand, 2005. I have been also working in Akdeniz University as a researcher and lecturer as an Associate Prof. Dr. position. Recently, I and my group are working on bacterial fish diseases and microalgea projects and also lecturing undergraduate and postgraduate level microbiology, genetics, molecular biology and marine microbiology in faculty.



Nannochlopsis oculata are important photosynthetic microalgae of aquatic environment, are the primary sources of many bioactive compounds. It is considered a promising organism for industrial and biotechnological applications because of its ability to accumulate high levels of polyunsaturated fatty acids. Microalge are nowadays used directly in food additive for human or animal nutrition, cosmetic and pharmaceutical industry, biofuel production, drug therapy and antimicrobial agent for human pathogens.

Bacterial fish diseases are the most important problem in aquaculture sector worldwide. Antibiotics and vaccine are the principal agents of protection and curing diseases however, accumulation and resistance to these drugs by pathogens are increasing problems aquaculture. Therefore, finding the environmental friendly alternative agents to control and cure fish pathogens are crucial in a country like Turkey which has production capacity of about 240 thousand tons of cultured fish which is the second biggest producer in Europe.

In our study, we tested the antimicrobial activity of Nannochloropsis oculata against fish pathogens for rainbow trout. Agar disk diffusion test method was used for studying antimicrobial activity on pathogens. Both Aeromonas spp. have shown antimicrobial activity positively as the inhibition zones were 10 -14 mm respectively. This results confirmed that both pathogens that have not shown groth activity in the presence of Nannochloropsis oculata extract. According to our primary results, future challenged projects for green aquaculture should be designed and tested with Nannochloropsis oculata extracts/biomass to control of diseases as an alternative sustainable reagent to synthetic antibiotics.

Keywords: Antimicrobial test, fish diseases, Nannochloropsis