EcoFoulPest

Context and objectives

A pesticide is defined as any substance used to kill, repel, or control certain forms of plant or animal life that are considered to be pests. They include herbicides for destroying weeds and other unwanted vegetation, insecticides for controlling a wide variety of insects, fungicides used to prevent the growth of molds, disinfectants for preventing the spread of bacteria, and rodenticides used to control mice and rats. The first synthetic pesticides became available during the 1940s. Organophosphate insecticides appeared in the 1960s, carbamates in 1970s and pyrethroids in 1980s. Herbicides and fungicides were introduced in the 1970s–1980s. Concern about their adverse impacts on the environment and on human health started being voiced in the early 1960s, resulting in the ban or restriction of the organochlorine insecticides, that had been used successfully in controlling a number of diseases up to that time. A large part of published material related to pesticides focuses on negative attributes and outcomes. Despite their hazards, tremendous benefits have been derived from the use of pesticides in forestry, public health, in the domestic sphere and, of course, in agriculture. Pesticides provide an unquestionable benefit by controlling pests (including diseases and weeds) and vectors of plant disease, by controlling human and livestock vectors and nuisance organisms, and by preventing or controlling organisms that impact other human activities and structures. To maximize the benefits of pesticide use at minimum human, environmental and economic costs, pesticides must be strictly regulated and used properly. However, the use of high volumes of pesticides in the past few decades has led to the development of resistance to pests. The current critical situation is that many of the previously used pesticides are no longer effective, thus the urgent need to develop new, more effective, target-specific and less persistent biocides.

In the search for new pesticides, several researches focused on marine natural products. It is well-known that the marine environment is an exceptional reservoir of bioactive products, which produce several novel structures absent from terrestrial natural products and with unique biological properties. A number of studies have suggested that some of the bioactive compounds isolated from marine organisms exhibit pesticidal properties. Such metabolites may be an environmentally-friendly alternative source for vector and agricultural pest control agents. Here, ECOFOULPEST project aims to further innovate the research effort towards the investigation of new pesticides by focusing on particular families of marine natural products with antifouling properties.

ECOFOULPEST objectives follow the key novel clear-cut aspects highlighted in the state-of-art. The main goal of ECOFOULPEST is to assess the potential of marine organisms to produce prototype eco-friendly tools for agriculture, especially herbicides and fungicides, and to further evaluate the potential hits. In parallel, I will investigate the biosynthetic pathway of the parent natural compound as well as its ecological role towards other marine organisms. Evaluation of such marine natural products and their biological properties will be executed through the following four concrete objectives, each corresponding to work packages (WP) listed on the Gantt chart.

Objective 1 (WP1):

Screening of known marine antifoulings for pesticidal, in particular herbicidal and fungicidal, properties. This objective is based on the screening of marine natural compounds readily available to identify agro-bioactivities. The hits will be further modified for Structure-Activity Relationship (SAR) purposes. In parallel, toxicology studies will be carried out in order to focus research in non-toxic compounds.

Objective 2 (WP2):

Screening of marine natural extracts (from fouling-free organisms) for pesticidal, in particular herbicidal and fungicidal, properties. In addition to the screening of known/putative antifouling compounds, it is also important to investigate new compounds through bioprospection. Easily accessible natural extracts will be screened on the selected biological targets. Hits will be isolated and identified.

Objective 3 (WP3):

Chemical ecology and biosynthesis. This objective aims at understanding the ecological role of such antifoulings and marine extracts in nature, as well as the biosynthetic pathways of the parent natural compounds.

Objective 4 (WP4):

Communication and dissemination. Communication and dissemination of the results will occur via seminars, conference presentations, public talks, submission of manuscripts to peer-reviewed science journals and local science outreach initiatives.

Results

During the first 6 months of the project, an extensive litterature review has been performed in order a) to select the compounds to investigate as pesticides and b) to select the organisms and specific pathways to target for bioassays .some of the selected compounds selected were then chemically synthetised. protocols for bio-assays were validated. Some extracts of marine macroalgae were produced using accelerated solvent extraction technics, a method which has the advantage of being environmentally friendly.