Abstract
•Nano colloid-protein interactions have significant impact on cellular behaviour of proteins.•P10 has the ability to modify the nano colloid-protein interactions.•The CcNc-induced protein destabilization with P10 as one component increases with acidic pH.•P10 and pH can be used to modulate the efficacy of CcNc formulations.
Unique properties of nano colloids make them diverse molecules of biological applications. The antimicrobial activity of nano colloids prepared from Cymbopogon citratus extract has been well documented. However, for the development of nano colloid-based products for human use, in-depth knowledge of the interactions between proteins and nano colloids is essential. Therefore, in this study, the interactions between the nano colloid synthesized using Cymbopogon citrates extract and holo alpha-lactalbumin (h-α-LA) in a crowded milieu was investigated using several techniques. Trp-fluorescence and far-UV CD measurements were carried out under different pH conditions, which showed significant perturbations in the tertiary and alpha-helical and β-sheet structural content of h-α-LA in the presence of nano colloid, P10. Presence of nano colloid in crowded milieu destabilized the protein in terms of midpoint of thermal denaturation (Tm) and Gibbs free energy (ΔGDo). In this manuscript, the effect of nano colloids on protein structure and stability under crowded cellular conditions was investigated. The CcNc in the presence of P10 has significant detrimental effect on protein’s native conformation which leads to decrease in its stability. This study hypothesised that P10 can be used for improving the efficacy of CcNc as antimicrobial agent.