title: Antiparasitic efficacy of curcumin from Curcuma longa against Ichthyophthirius multifiliis in grass carp.
abstract: Ichthyophthirius multifiliis is a ciliated parasite that elicits great economic losses in aquaculture. In the present study, a polyphenol compound, curcumin, was obtained from the rhizome of Curcuma longa by bioassay-guided isolation based on the efficacy of anti-I. multifiliis theronts. Anti-I. multifiliis efficacy of curcumin was evaluated in vitro and in vivo. Curcumin resulted in 100% mortality of I. multifiliis theronts at a concentration of 1mg/L within 21.7±1.2min and killed all tomonts at 8mg/L within 31.0±1.0min. Curcumin at 4mg/L for 16h exposure can completely terminate the reproduction of tomonts. The pretreatment with curcumin at concentrations of 0.5, 0.25, and 0.125mg/L for 2h significantly reduced the infectivity of I. multifiliis theronts. Curcumin at 4mg/L completely cured the infected grass carp and protected naive fish from I. multifiliis infection after 10days exposure. The 4h median effective concentration (EC50) of curcumin to I. multifiliis theronts and the 5h EC50of curcumin to I. multifiliis tomonts were 0.303mg/L and 2.891mg/L, respectively. The 96h median lethal concentration (LC50) of curcumin to grass carp was 56.8mg/L, which was approximately 187.4 times EC50of curcumin to theronts and 19.6 times EC50of curcumin to tomonts. The results demonstrated that curcumin has the potential to be a safe and effective therapeutant for controlling ichthyophthiriasis in aquaculture.
authors.affiliation: Key Laboratory of Aquatic Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering Ministry of Education, Institute of Hydrobiology, Jinan University, West 601 Huangpu Avenue, Tianhe District, Guangzhou 510632, People's Republic of China.
authors.forename: Yan-Meng
authors.initials: YM
authors.lastname: Liu
authors.affiliation: Key Laboratory of Aquatic Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering Ministry of Education, Institute of Hydrobiology, Jinan University, West 601 Huangpu Avenue, Tianhe District, Guangzhou 510632, People's Republic of China. Electronic address: zhangqzdr@126.com.
authors.forename: Qi-Zhong
authors.initials: QZ
authors.lastname: Zhang
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Aquatic Animal Health Research Unit, 990 Wire Road, Auburn, AL 36832-4352, USA.
authors.forename: De-Hai
authors.initials: DH
authors.lastname: Xu
authors.affiliation: Key Laboratory of Aquatic Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering Ministry of Education, Institute of Hydrobiology, Jinan University, West 601 Huangpu Avenue, Tianhe District, Guangzhou 510632, People's Republic of China.
authors.forename: Yao-Wu
authors.initials: YW
authors.lastname: Fu
authors.affiliation: Key Laboratory of Aquatic Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering Ministry of Education, Institute of Hydrobiology, Jinan University, West 601 Huangpu Avenue, Tianhe District, Guangzhou 510632, People's Republic of China.
authors.forename: De-Jie
authors.initials: DJ
authors.lastname: Lin
authors.affiliation: Key Laboratory of Aquatic Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering Ministry of Education, Institute of Hydrobiology, Jinan University, West 601 Huangpu Avenue, Tianhe District, Guangzhou 510632, People's Republic of China.
authors.forename: Sheng-Yu
authors.initials: SY
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Aquatic Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering Ministry of Education, Institute of Hydrobiology, Jinan University, West 601 Huangpu Avenue, Tianhe District, Guangzhou 510632, People's Republic of China.
authors.forename: Jian-Pei
authors.initials: JP
authors.lastname: Li
mesh_terms: D000818:Animals; D000981:Antiprotozoal Agents / Q000009:adverse effects / Q000494:pharmacology*; D002347:Carps; D016770:Ciliophora Infections / Q000188:drug therapy / Q000469:parasitology / Q000662:veterinary*; D003474:Curcumin / Q000009:adverse effects / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005393:Fish Diseases / Q000188:drug therapy* / Q000469:parasitology; D016803:Hymenostomatida / Q000187:drug effects* / Q000502:physiology; D011897:Random Allocation
chemical_list: D000981:Antiprotozoal Agents; D003474:Curcumin
keywords: Acute toxicity; Antiparasitic efficacy; Curcuma longa; Curcumin; Ichthyophthirius multifiliis