title: Assessment of safety and efficiency of nitrogen organic fertilizers from animal-based protein hydrolysates--a laboratory multidisciplinary approach.
abstract: BACKGROUND
  Protein hydrolysates or hydrolysed proteins (HPs) are high-N organic fertilizers allowing the recovery of by-products (leather meal and fluid hydrolysed proteins) otherwise disposed of as polluting wastes, thus enhancing matter and energy conservation in agricultural systems while decreasing potential pollution. Chemical and biological characteristics of HPs of animal origin were analysed in this work to assess their safety, environmental sustainability and agricultural efficacy as fertilizers. Different HPs obtained by thermal, chemical and enzymatic hydrolytic processes were characterized by Fourier transform infrared spectroscopy and sodium dodecyl sulfate polyacrylamide gel electrophoresis, and their safety and efficacy were assessed through bioassays, ecotoxicological tests and soil biochemistry analyses.
  
  
  RESULTS
  HPs can be discriminated according to their origin and hydrolysis system by proteomic and metabolomic methods. Three experimental systems, soil microbiota, yeast and plants, were employed to detect possible negative effects exerted by HPs. The results showed that these compounds do not significantly interfere with metabolomic activity or the reproductive system.
  
  
  CONCLUSIONS
  The absence of toxic and genotoxic effects of the hydrolysates prepared by the three hydrolytic processes suggests that they do not negatively affect eukaryotic cells and soil ecosystems and that they can be used in conventional and organic farming as an important nitrogen source derived from otherwise highly polluting by-products.
authors.affiliation: Department of Applied Biology-Microbiology, University of Perugia, Borgo XX Giugno 74, I-06121, Perugia, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Corte
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Dell'abate
authors.forename: Alessandro
authors.initials: A
authors.lastname: Magini
authors.forename: Melania
authors.initials: M
authors.lastname: Migliore
authors.forename: Barbara
authors.initials: B
authors.lastname: Felici
authors.forename: Luca
authors.initials: L
authors.lastname: Roscini
authors.forename: Roccaldo
authors.initials: R
authors.lastname: Sardella
authors.forename: Brunella
authors.initials: B
authors.lastname: Tancini
authors.forename: Carla
authors.initials: C
authors.lastname: Emiliani
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Cardinali
authors.forename: Anna
authors.initials: A
authors.lastname: Benedetti
mesh_terms: D000818:Animals; D017753:Ecosystem; D004787:Environmental Pollution; D005308:Fertilizers; D009584:Nitrogen / Q000378:metabolism*; D011492:Protein Hydrolysates / Q000009:adverse effects; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000378:metabolism; D012449:Safety; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D031306:Vicia / Q000187:drug effects* / Q000378:metabolism
chemical_list: D005308:Fertilizers; D011492:Protein Hydrolysates; D012987:Soil; D009584:Nitrogen
keywords: N organic fertilizers; agronomical efficiency; environmental safety; hydrolysed proteins (HPs); waste biotransformation