RESEARCH ARTICLE Role of Nanocurcumin as a Surface Modifying Agent with Excellent Preventive Effect on Device-Related CoNS Infections K. R. Soumya 1 • P. Jishma 1 • R. Dhivya 2 • Jamespandi Annaraj 2 • Sheela Sugathan 3 • Jyothis Mathew 1 • E. K. Radhakrishnan 1 Received: 9 August 2018 / Revised: 10 December 2018 / Accepted: 9 January 2019 Ó The National Academy of Sciences, India 2019 Abstract The study focused on the analysis of efficiency of curcumin and nanocurcumin (NC) against biofilm- forming methicillin-resistant clinical isolates of Staphylo- coccus epidermidis and Staphylococcus haemolyticus. Antibacterial, minimum inhibitory concentration and anti- biofilm activities of both curcumin and NC were carried out, and the specific changes were analyzed by transmis- sion electron microscopy (TEM). Surface modifying effect of NC was further analyzed by coating it onto nasogastric polyvinyl chloride (PVC) tubes followed by challenging it with selected pathogens, and the results were visualized by scanning electron microscopy. Curcumin and NC were found to have antibacterial effects at a concentration of 100 and 10 lg mL -1 , respectively. Also 250 and 500 lg mL -1 concentrations of NC were found to have 99% inhibition on biofilm formation of S. epidermidis and S. haemolyticus. TEM analysis of NC-treated coagulase-negative staphylo- cocci (CoNS) samples showed remarkable inhibition of biofilm formation with the complete lysis of bacterial cell. NC functionalization showed excellent preventive effect on bacterial adhesion and biofilm formation on nasogastric PVC catheters and hence has the promises to be used as alternative chemotherapeutic agents. The current study forms the first report on detailed investigation on potential of NC as an effective agent against CoNS, which is well known for biomedical infection. Keywords Antibiofilm Á MRCoNS Á Nanocurcumin Á Ryle’s tube Á Surface modification Introduction Curcumin is a natural polyphenolic flavonoid present in the rhizome of Curcuma longa L. This has been used from ancient times in Ayurvedic medicines due to its antioxidant and free radical scavenging properties [1, 2]. Curcumin has wide range of applications as anti-inflammatory, antioxi- dant, anticarcinogenic, antimutagenic, antidiabetic, antibacterial, antifungal, antiprotozoal, antifibrotic, antiul- cer and hypocholesterolemic agent [3]. Antibacterial effects of curcumin on both Gram-positive and Gram- negative bacteria of clinical significance have already been demonstrated in various studies [4]. Also many reports are there on its antibiofilm activity against S. aureus, E. coli, Pseudomonas spp., S. mutans and H. pylori [5]. Apart from all these multidisciplinary beneficial effects, therapeutic use of curcumin is limited due to its poor solubility, metabolism, rapid elimination and less bioavailability [6]. Nanomised curcumin particles called nanocurcumin have been suggested to have enhanced bioactivity due to its high surface area-to-volume ratio [7]. The excellent physicochemical features of nanocurcumin have also resulted in its improved solubility, bioavailability, enhanced absorbance and reduced medicinal doses with an Significance statement Nanocurumin functionalization on nasogastric catheter prevented adhesion and biofilm formation by coagulase-negative staphylococci. & E. K. Radhakrishnan radhakrishnanek@mgu.ac.in 1 School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala 686560, India 2 Department of Materials Science, School of Chemistry, Madurai Kamaraj University, Madurai 625021, India 3 Sree Narayana Institute of Medical Sciences, Chalakka, Ernakulam, Kerala 683594, India 123 Proc. Natl. Acad. Sci., India, Sect. B Biol. Sci. https://doi.org/10.1007/s40011-019-01075-z