Review Use of plant extracts in fish aquaculture as an alternative to chemotherapy: Current status and future perspectives M. Reverter a,b,c, ⁎, N. Bontemps b , D. Lecchini a,c , B. Banaigs b , P. Sasal a a CRIOBE, USR 3278 - CNRS/EPHE/UPVD, Centre de Recherches Insulaires et Observatoire de l'Environnement, BP1013 Papetoai, 98729 Moorea, French Polynesia b CRIOBE, USR 3278 - CNRS/EPHE/UPVD, University of Perpignan Via Domitia, 52 Avenue Paul Alduy, 66860 Perpignan, France c Laboratoire d'Excellence “CORAIL”, 98729 Moorea, French Polynesia abstract article info Article history: Received 13 May 2014 Received in revised form 28 May 2014 Accepted 30 May 2014 Available online 7 June 2014 Keywords: Plant extracts Fish aquaculture Disease resistance Immunostimulant Natural products Aquaculture is the main source to increase fish supply. Fast development of aquaculture and increasing fish de- mand lead to intensification of fish culture, magnifying stressors for fish and thus heightening the risk of disease. Until now, chemotherapy has been widely used to prevent and treat disease outbreaks, although use of chemical drugs has multiple negative impacts on environment and human health e.g. resistant bacterial strains and resid- ual accumulation in tissue. Hence, disease management in aquaculture should concentrate on environmentally friendly and lasting methods. Recently, increasing attention is being paid to the use of plant products for disease control in aquaculture as an alternative to chemical treatments. Plant products have been reported to stimulate appetite and promote weight gain, to act as immunostimulant and to have antibacterial and anti-parasitic (virus, protozoans, monogeneans) properties in fish and shellfish aquaculture due to active molecules such as alkaloids, terpenoids, saponins and flavonoids. However, as it is a relatively emerging practice there is still little knowledge on the long-term effects of plant extracts on fish physiology as well as a lack of homogenization in the extract preparation and fish administration of the plant extracts. This article aims to review the studies carried out on the use of plant products on fish aquaculture and their biological effects on fish such as growth promoter, immunostimulant, antibacterial and anti-parasitic. It also intends to evaluate the current state of the art, the methods used and the problems encountered in their application to the aquaculture industry. © 2014 Elsevier B.V. All rights reserved. Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 2. Potential of plant extracts in aquaculture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 2.1. Plant extracts as appetite stimulators and growth promoters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 2.2. Plant extracts as immunostimulants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 2.3. Plant extracts as fish anti-pathogenic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 2.3.1. Antibacterial. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 2.3.2. Anthelminthic (monogeneans) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 2.3.3. Other parasites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 3. Isolated natural products with anti parasitic properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 4. Conclusion and perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 1. Introduction Fish and fishery products represent a very valuable source of protein and essential micronutrients for balanced nutrition and good health. In 2009, fish accounted for 17% of the world population intake of animal protein and 6.5% of all protein consumed. World fish food supply has Aquaculture 433 (2014) 50–61 ⁎ Corresponding author at: Centre de Recherches Insulaires et Observatoire de l'Environnement, BP1013 Papetoai, 98729 Moorea, French Polynesia. Tel.: +689 56 13 45; fax: +689 56 28 15. E-mail address: mirireverter@gmail.com (M. Reverter). http://dx.doi.org/10.1016/j.aquaculture.2014.05.048 0044-8486/© 2014 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Aquaculture journal homepage: www.elsevier.com/locate/aqua-online