Use Of Glucan From Saccharomyces Cerevisiae As An Immunostimulant In Carp: Impact On Hematology, Phagocyte Function, And Infection With Aeromonas Hydrophila

Abstract

Glucan was extracted from yeast (Saccharomyces cerevisiae) and subjected to chemical analy- ses. Thin layer chromatography (TLC) revealed that glucan is primarily composed of glucose units and contains 97.2% glucose. Infrared spectrum showed a major band at 883/cm, suggest- ing that glucan is linked to β-glycosidic. Intraperitoneal administration of different doses of glu- can enhanced the survival rate of carp (Cyprinus carpio) infected by Aeromonas hydrophila. When a concentration above 500 μg glucan per fish was administered, survival relative to the uninfected control was 100%. The total leukocyte count and neutrophil and monocyte popula- tions increased after administration of the glucan. The maximum effect occurred on day 6 after injection. Macrophages of compound-administrated test animals significantly increased produc- tion of superoxide anions, efficiently killing the bacterial pathogen. This study showed that glu- can can be effective in inducing non-specific cellular defense mechanism in carp.