CURCUMIN WITH SCHIFF BASE FUNCTIONALITY: SYNTHESIS, ANTIMICROBIAL ACTIVITIES

Abstract

Curcumin is a natural substance that has a wide range of biological functions and is a source to several medications. It is becoming more difficult to produce a natural-based drugs that can prevent bacterial antibiotic resistance. To achieve this goal, Schiff bases were prepared by a one pot process that involves reacting curcumin with various amino acids. The amino acids selected for this work were those with heterocyclic functionality in addition to the amine and the carboxylic groups. The selected were histidine, lysine, cysteine, and arginine. The structures of the produced compounds were tested by FT-IR, H NMR, mass spectral analysis and antibacterial activity. Schiff bases was tested against gram-positive bacteria which are Staphylococcus aureus, Staphylococcus epidermidis, and methicillin-resistant Staphylococcus aureus. And with gram-negative bacteria which are Escherichia coli and Klebsiella pneumonia. The Schiff base 5 which produced from reacting curcumin with arginine was the most effective MIC value of 200 µg mL-1. The Schiff base 2 which produced from reacting curcumin with histidine changed the DNA of E. coli strain, this could be attributed to the presence of many nitrogen atoms in the structure of the compound. Keywords: Schiff bases, natural substance, Curcumin, amino acids.