Technical actions

A. Preparatory actions

A series of agri-food by-products, both crop pruning as agroindustry residues, with proven biocide activity compounds have been selected and gathered.
The objective is the development of a residual biomass supply plan for the manufacturing of extracts that will take part in the composition of new pesticide formulates, replacing the chemical origin ones used a t present.
ICA-CSIC and CTAEX working teams have selected and gathered three kinds of agri-food by-products as source of biocide compounds:
a)    Plant solid residues from the steam distillation of aromatic species: wormwood, winter savory, dittrichia, groso lavender, red thyme, oregano and olivardilla.
b)    Vegetable processing residues: blanched artichokes and asparagus, and their blanching water, and alperujo (olive oil mill waste water).
c)    Pruning from different crops:  lemon, orange and grapefruit, olive tree, eucalyptus and fine chips from eucalyptus, holm oak and black poplar pruning 
Generation periods, their conditions and volumes produced have also been recorded, in order to assure suppliers for pilot extractions from theses residual biomass. The corresponding deliverable compiles all the information.

B. Implementation actions

The following eight agricultural by-products are available

1.    Artichoke peels
2.    Water from artichoke blanching
3.    Asparagus peels
4.    Water from asparagus blanching
5.    AJENJO var. Candial (extracted wormwood)
6.    AJEDREA: Satureja montana parental line (extracted winter savory)
7.    SAMO: S. montana var. Martín (extracted winter savory var. Martin)
8.    Dittrichia graveolens (extracted stinkwort)

The fresh artichoke and asparagus vegetable and water residues of from the canning processes were frozen and lyophilized. All plant materials were dried in a stove with circulating air at 35ºC. Once dried, we can proceed to mill it and subsequent extraction.

Extraction: depending on the starting material, a solid-liquid (Sohxlet type) or liquid-liquid extraction is carried out, following the established protocols in this action.
 

An extraction protocol has been developed in order to obtain micro-extract from the agroindustry by-products with potential bio pesticide capacity collected. Due to the different agri-food by-products’ physical nature, two different extraction protocols have been defined:
-    Solid- liquid Soxhlet extraction, for solid residues and for those liquid ones that required previous lyophilization, such as blanching waters, using Ethanol as extracting agent.
-    Liquid- liquid extraction, with Ethanol also, for liquid by-products.

 

The objective is the obtaining of by-products´ micro-extracts that will be assessed on their biocide capacity over organisms causing pests and diseases of stone fruits.
ICA-CSIC and CTAEX working teams have carried out the extractions and assessed their yield regarding their industrial scale-up.

Insecticidal, nematicide, bactericidal and fungicidal activities of micro-extracts from agri-food by-products have been assessed at ICA-CSIC and CTAEX laboratories according to standardized analytical protocols. These assays include antifeedant activity to phytophagous insects, tests with phytophagous nematodes, fungistatic and bactericidal capacity.
The by-products´ micro-extracts with higher bio pesticidal activity have been selected and will be tested in binary mixes for the strengthen of their synergic activity.
All this information is compiled in the corresponding deliverable: Report on extracts´ validation.