Assessment of the impact of chlorophyll derivatives to control parasites in aquatic ecosystems

Abstract

Several research groups have studied new biopesticides which are less toxic to the environment and capable of controlling the vectors of parasitic diseases, especially in aquatic ecosystems. Pest control by photodynamic substances is an alternative to chemical or other measures, with chlorophyll and its derivatives as the most studied substances supported by their easy availability and low production costs. The impact of chlorophyll derivatives on four different species, a small crustacean (Daphnia similis), a unicellular alga (Euglena gracilis) and two species of fish (Astyanax bimaculatus and Cyprynus carpio) were tested under short-term conditions. In addition, the effects of long-term exposure were evaluated in D. similis and E. gracilis. In short-term tests, mortality of D. similis (EC50 = 7.75 mg/L) was most strongly affected by chlorophyllin, followed by E. gracilis (EC50 = 12.73 mg/L). The fish species showed a greater resistance documented by their EC50 values of 17.58 and 29.96 mg/L in C. carpio and A. bimaculatus, respectively. A risk quotient is calculated by dividing an estimate of exposure by an estimate of effect. It indicated that chlorophyll derivatives can be applied in nature to control the vectors of parasitic diseases under short-term conditions, but long-term exposure requires new formulations.

Chlorophyllin Treatment Against the Snail Lymnaea acuminata: A new tool in Fasciolosis Control

“…It is reported that chlorophyllin was able to kill four different species, a small crustacean (Daphnia similis), a unicellular alga (Euglena gracilis) and two species of fish (Astyanax bimaculatus and Cyprynus carpio) the vector of parasitic diseases. 19 Although it has been reported 19 that chlorophyllin is toxic against Astyanax bimaculatus and Cyprynus carpio, yet in our observation it is not toxic against C. fasciatus. Both extracted and pure chlorophyllin are more effective in summer than winter.…”

Chemistry in the Bioactivity of Chlorophylls: An Overview

“…Chlorophylls should be incubated in dark conditions for a few hours to accumulate in the larvae and subsequent exposure to light, for example applying chlorophyll derivatives to water at night, which will be accumulated in larvae and photodynamic reaction will start with the sunrise [7]. In this sense, chlorophyllin and pheophorbide are fatal to larvae of Culex and Chaoborus [125], chlorophyllin effectively kills Aedes and Anopheles species [126] and even chlorophyll derivatives are effective against the larvae of freshwater snail [127] and certain parasites of fish [128].…”

Photomediated Larvicidal Activity of Pheophorbide a against Cercaria Larvae of Fasciola gigantica

“…Photolarvicidal activity of red spectral band irradiated Pa was followed by white and sunlight irradiance. It has been advocated by various scientists that chlorophyll derivatives like chlorophyllin and pheophorbide show more photomediated control of disease caused by mosquito and insect larvae [12, 13, 16]. The EC 50 values exposed to pheophorbide for 3 h to a light intensity of 147 W/m 2 were 8.44 mg/L and 1.05 mg/L against Culex and Chaoborus mosquito larvae, respectively [11].…”