Lemna gibba and Eichhornia crassipes extracts: Clean alternatives for deacidification, antioxidation and fungicidal treatment of historical paper.

Abstract In this research Lemna gibba (L) and Eichhornia crassipes (E) ethanolic extracts were added to pure cellulose substrate to produce impregnated interleaving papers (LIP) and (EIP). These products are proposed to cure historical paper undergoing acidification, oxidation and fungal infection. The extracts were analysed using Gas Chromatography/Mass Spectrometer (GC/MS) and polyphenolic compounds were assessed. The products were tested on model decayed paper showing identical characteristics of historical paper, on which pH values were measured, transition metals concentrations were evaluated using Inductively Coupled Plasma- Optical Emission Spectrometry (ICP-OES) and samples were investigated using Scanning Electron Microscope combined with Energy Dispersive Spectroscopy (SEM-EDX) respectively. Radical scavenging and antioxidation activities of the extracts were also assessed using 1,1-diphenyl-2-picryl-hydrazyl free radical DPPH·. Results demonstrated a significant increase (P < 0.01) in the DPPH· free radical scavenging with increasing concentration in the following order vitamin C > BHT ≈ (L) extract > (E) extract. Results showed also that both (LIP) and (EIP) products effectively neutralized the acidity of decayed paper after 7 day treatment and evidently chelated transition metals. Zn2+ and Fe2+ were better chelated by (LIP) treatment in the order; Zn2+ > Fe2+ > Pb2+ > Cu2+, while Pb2+ and Cu2+ were greater removed by (EIP) treatment in the order Pb2+ > Cu2+ > Zn2+ > Fe2+. Up to 90% radical scavenging was achieved at 320.00 μg/mL concentration of (L) extract and 667.296 μg/mL concentration of (E) extracts. Aspergillus niger , Penicillium roqueforti and Eurotium chevalieri growth are inhibited at 1000 μg/mL concentration of LIP with considerable fungal spots elimination. Our findings established LIP and EIP products as novel natural origin alternative for effective synergic deacidification, antioxidation, antiradical, metal chelation and fungicidal treatment of historical paper. Graphical abstract Image 1 Highlights • Treatment of ink induced corrosion of historical paper with novel eco-friendly method. • We produced clean products from Lemna gibba and Eichhornia crassipes extracts. • Treatments neutralized the acidity of paper and slightly enhanced the manuscript legiblity • LIP gave better performance for Fe and Zn chelation after 7 day treatment. • The growth of the tested fungi was inhibited by the treatment. [ABSTRACT FROM AUTHOR]