Turkish Journal of Fisheries and Aquatic Sciences
2015, Vol 15, Num, 1 (Pages: 49-57)
Evaluation of Antibacterial Activity of Green Tea (Camellia sinensis L.) Seeds Against Some Fish Pathogens in Rainbow Trout (Oncorhynchus mykiss, Walbaum)
Halis Boran 1 ,Cengiz Çiftci 1 ,Akif Er 1 ,Özay Köse 1 ,İlker Zeki Kurtoğlu 1 ,Şevki Kayış 1
1 Recep Tayyip Erdoğan University, Faculty of Fisheries, Rize, Turkey
DOI :
10.4194/1303-2712-v15_1_06
Viewed :
5708
-
Downloaded :
7748
In aquaculture, bacterial fish diseases are still one of the most serious problem and fish mortality of bacterial origin can
cause significant economic losses worldwide. The evolution of microorganism resistance to antibiotics has resulted in
growing need for new antibacterial compounds. In the present study, the antibacterial activity of green tea (Camellia sinensis
L.)seed and its secondary metabolite saponin were evaluated on five bacterial fish pathogens that cause diseases in rainbow
trout (Oncorhynchus mykiss, Walbaum). In addition to this, possible histological effects were investigated on the vital organs
of fish. The antibacterial activity of tea seed and saponin were determined using the agar diffusion method. Watered tea seed
(WTS) powder and saponin used in this research as the feed additives demonstrated antibacterial activity against the five
pathogens but statistically significant inhibition was observed only with Listonella anguillarum. Accordingly, significantly
higher survival levels were observed in fish infected with L. anguillarum in WTS and saponin diet groups. However, organs
of fish fed with WTS and saponin showed some nonvital symptoms such as hyperplasia and epithelial lifting in the gills and
lipid droplets, intercellular edema and nuclear degeneration in liver. Results from this study confirmed the potential use of
WTS as a source of antibacterial compounds or as a feed additive for prevention of disease against L. anguillarum infection in
trout culture.
Keywords :
Tea seed, saponin, antibacterial activity, histopathology, rainbow trout