How olive mill wastewater could turn into valuable bionanoparticles in improving germination and soil bacteria

• Published in: Industrial crops and products 2022-11, Vol.188, p.115682, Article 115682
• Main Authors: Hamimed, Selma, Chamekh, Anissa, Slimi, Hamda, Chatti, Abdelwaheb
• Format: Article
• Language: English
• Subjects: Green synthesis; Magnesium sulphide nanoparticles; Olive mill wastewater; Seed germination; Soil bacteria
• ISSN: 0926-6690; 1872-633X
• DOI: 10.1016/j.indcrop.2022.115682

Olive mill wastewater (OMW) is a hazardous effluent due to large quantities of pollutant compounds, such as polyphenols. Land spreading of untreated OMW comes with severe toxicity on agricultural lands. Cleaning up OMW via the extraction of polyphenols was employed as reducing, capping, and stabilizing agents to biosynthesize magnesium sulfide nanoparticles (MgS NPs). Detailed characterization spectroscopy analysis revealed the appearance of peaks at 439, 593, and 667 cm−1 confirming the synthesis of MgS NPs. In addition, XRD showed the characteristic peaks of MgS NPs with an average crystalline size of 86.3 nm. TEM and EDX confirmed the high purity of nanoparticles with irregular spherical shapes. For the first time, the biogenic MgS NPs were investigated in the germination of old pea (Pisum sativum L. var.) and soil bacteria. Results demonstrated positive efficacy in the germination growth promotion of seeds and bacterial growth. Machine learning classifiers suitable for our study were mentioned, and SVC performs showed the best with accuracy and an F1 score of 86 %. Further investigations are required to determine the efficacy of these nanoparticles in agriculture. [Display omitted] •Purely synthesized magnesium sulphide nanoparticles (MgS NPs) by olive mill wastewater.•Dual processes deal with cleaning up OMW and upcycled biomolecules in valuable nanoproducts.•A low concentration of MgS NPs was beneficial in bacterial and germination enhancement.•Machine learning modelling was used to explore the efficiency of MgS NPs application.