Quaternization of cassava starch and determination of antimicrobial activity against bacteria and coronavirus

• Published in: Carbohydrate research Vol. 538; p. 109098
• Main Authors: Ribeiro de Carvalho, Guilherme, Kudaka, Amanda Miki, Fares Sampar, Jórdan, Alvares, Lúcia Elvira, Delarmelina, Camila, Duarte, Marta Cristina Teixeira, Lona, Liliane Maria Ferrareso
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.04.2024
• Subjects: Ammonium Compounds; Cassava starch modification; Coronavirus; GTMAC; Manihot - chemistry; Staphylococcus aureus; Starch - chemistry; GTMAC; Cassava starch modification; Coronavirus
• ISSN: 0008-6215; 1873-426X
• DOI: 10.1016/j.carres.2024.109098

This study describes the novel development of quaternized cassava starch (Q-CS) with antimicrobial and antiviral properties, particularly effective against the MHV-3 coronavirus. The preparation of Q-CS involved the reaction of cassava starch (CS) with glycidyltrimethylammonium chloride (GTMAC) in an alkaline solution. Q-CS physicochemical properties were determined by FTIR, NMR, elemental analysis, zeta potential, TGA, and moisture sorption. FTIR and NMR spectra confirmed the introduction of cationic groups in the CS structure. The elemental analysis revealed a degree of substitution (DS) of 0.552 of the cationic reagent on the hydroxyl groups of CS. Furthermore, Q-CS exhibited a positive zeta potential value (+28.6 ± 0.60 mV) attributed to the high positive charge density shown by the quaternary ammonium groups. Q-CS demonstrated lower thermal stability and higher moisture sorption compared to CS. The antimicrobial activity of Q-CS was confirmed against Escherichia coli (MIC = 0.156 mg mL−1) and Staphylococcus aureus (MIC = 0.312 mg mL−1), along with a remarkable ability to inactivate 99% of MHV-3 coronavirus after only 1 min of direct contact. Additionally, Q-CS showed high cell viability (close to 100%) and minimal cytotoxicity effects, guaranteeing its safe use. Therefore, these findings indicate the potential use of Q-CS as a raw material for antiseptic biomaterials. [Display omitted] •Quaternized cassava starch (Q-CS) has been successfully synthesized.•Q-CS showed notable antibacterial and antiviral activity against MHV-3 coronavirus.•Q-CS proved to be a promising biopolymer for producing antimicrobial materials.