Antiviral abilities of Curcuma kwangsiensis ingredients against grouper iridoviral infection in vitro and in vivo

As one of the most serious pathogens in mariculture, the outbreaks of grouper Iridovirus (SGIV-Gx) caused high mortality rates in cultured groupers in Guangxi, China. Hence, effective medicines for fighting against grouper Iridovirus are urgently needed. The possible application of Curcuma kwangsiensis ingredients against SGIV-Gx infection was evaluated in vitro and in vivo in this study. The safe working concentration of each C. kwangsiensis ingredient was identified (C. kwangsiensis ethanol ingredient, CKEE <= 5 mg/ml; curcumin <= 20 mu g/ml; curdione <= 500 mu g/ml; curcumenol <= 500 mu g/ml; curcumol displayed no cytotoxic effects even at 2 mg/ml) in vitro and in vivo. The inhibitory activities of each C. kwangsiensis ingredient against SGIV-Gx infection were analysed using aptamer (Q2)-based fluorescent molecular probe (Q2-AFMP) and RT-qPCR. The results showed that C. kwangsiensis ingredient (CKEE, curcumin, curcumol, curdione and curcumenol) displayed antiviral activities against SGIV-Gx infection in a dose-dependent manner. Furthermore, according to the inhibitory percentage analysed using RT-qPCR results, CKEE and curdione had the best antiviral activity against SGIV-Gx above 93%. Overall, the results suggest that some C. kwangsiensis ingredients have excellent antiviral effects, making it an interesting candidate for developing effective medicines for preventing and controlling SGIV-Gx outbreaks in mariculture.