Coumarin-6-sulfonyl derivative: a novel antimicrobial candidate and agriculture control of strawberry black root-rot and cotton leafworm

Abstract

A new methyl 2-[(coumarin-6-yl)sulfonyl] hydrazine-1-carbodithioate (II) was building and tested for its antimicrobial, biofilm formation inhibition, and agriculture fighting of strawberry black root-rot and cotton leafworm. Antimicrobial activity results indicated that II showed considerable antibacterial activity having MIC values of 78.43 ± 1.928 and 158.67 ± 2.137 μg/mL toward S. aureus and E. coli, while it was superior in inhibiting C. albicans and A. niger with MIC values of 20.27 ± 2.359 and 9.71 ± 0.702 μg/mL than the reference nystatin. Anti-biofilm formation result showed that, II demonstrated anti-biofilm efficacy against S. aureus with MIC: 55.91 ± 1.642 μg/mL (1.5-fold) and C. albicans with MIC: 78.705 ± 2.048 μg/mL (4-fold) higher than the reference. The Cytotoxic activity against the normal cell line (Wi38) indicated that II was safe, as it showed an IC₅₀ ≥100 μg/mL. Regarding the efficacy towards strawberry black root-rot pathogens, compound II showed complete growth inhibition of Fusarium solani and Pythium sp., at 80.0 and 40.0 μg/mL, respectively (Laboratory exp.). In the field trial, II diminished black root rot incidence besides severity by 70.5 and 72.2 %, respectively. For the cotton leafworm, S. littoralis, compound II showed a significant effect (LC₅₀: 395.68 μg/mL and LC₉₀: 561.87 μg/mL). The mechanism of antimicrobial activity was suggested to be by action on multiple targets while the insecticidal activity against S. littoralis larvae was proposed to be by AChE inhibition applying the molecular modeling computation.