Biostimulants derived from organic urban wastes and biomasses: An innovative approach

Alessia Giordana; Mery Malandrino; Alfonso Zambon; Gigliola Lusvardi; Lorenza Operti; Giuseppina Cerrato

doi:10.3389/fchem.2023.969865

Biostimulants derived from organic urban wastes and biomasses: An innovative approach

Front Chem. 2023 Feb 10:11:969865. doi: 10.3389/fchem.2023.969865. eCollection 2023.

Authors

Alessia Giordana¹, Mery Malandrino¹, Alfonso Zambon², Gigliola Lusvardi², Lorenza Operti¹, Giuseppina Cerrato¹

Affiliations

¹ Dipartimento di Chimica, Università degli Studi di Torino, Turin, Italy.
² Dipartimento di Scienze Chimiche e Geologiche, Università degli Studi di Modena e Reggio Emilia, Modena, Italy.

Abstract

We used humic and fulvic acids extracted from digestate to formulate nanohybrids with potential applications in agronomy. In order to obtain a synergic co-release of plant-beneficial agents, we functionalized with humic substances two inorganic matrixes: hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂, HP) and silica (SiO₂) nanoparticles (NPs). The former is a potential controlled-release fertilizer of P, and the latter has a beneficial effect on soil and plants. SiO₂ NPs are obtained from rice husks by a reproducible and fast procedure, but their ability to absorb humic substances is very limited. HP NPs coated with fulvic acid are instead a very promising candidate, based on desorption and dilution studies. The different dissolutions observed for HP NPs coated with fulvic and humic acids could be related to the different interaction mechanisms, as suggested by the FT-IR study.

Keywords: biostimulant; fulvic acid; humic acid; hydroxyapatite; nanofertilizer; rice husk; silica.

Grants and funding

Partial funding was obtained by the SATURNO project (Scarti organici e Anidride carbonica Trasformati in carbURanti, fertilizzanti e prodotti chimici; applicazione concreta dell’ecoNOmia circolare): this is a Piedmont regional project for the activities devoted to circular economy, active in the framework of POR F.E.S.R. 2014/2020 funding from the European Commission (Actions I.1b.2.2 and 1.8.II.2.3.1) at https://saturnobioeconomia.it/.