# Antimicrobial and anti-cancer potential of turmeric synthesized AuNPs and Chitosan-AuNP nanocomposites against MDR pathogens and breast/colorectal carcinoma cells

## TL;DR

This study explores the antimicrobial and anti-cancer properties of turmeric-based gold nanoparticles and their chitosan composite against drug-resistant bacteria and cancer cells.

## Contribution

The study introduces a novel nanocomposite combining turmeric-synthesized gold nanoparticles with chitosan for dual antimicrobial and anticancer applications.

## Key findings

- NCS-TAuNPs showed higher antibacterial activity against K. pneumoniae and E. coli compared to TAuNPs alone.
- Both TAuNPs and NCS-TAuNPs exhibited significant cytotoxic effects on MCF-7 and HCT-116 cancer cell lines.
- The nanocomposites demonstrated strong antioxidant and anti-biofilm properties.

## Abstract

The rise in antimicrobial resistance to current antibiotics has driven the search for novel natural compounds with antimicrobial properties. This study aimed at evaluate the Antimicrobial, Anti-Biofilm, and Cytotoxic Potential of Turmeric synthesized AuNPs and Chitosan-AuNP Nanocomposites against MDR urinary tract infections (UTIs) Pathogens (K. pneumoniae and E. coli) and MCF-7 & HCT-116 Cancer Cell Lines. Biosynthesize- characterization of turmeric-gold nanoparticles (TAuNPs) using methanolic extract of Curcuma longa rhizome by Transmission Electron Microscopy (TEM), X-ray spectroscopy, Fourier Transform Infrared (FT-IR) spectroscopy, and Zeta potential (Z-potential) analysis. Coated biosynthesized TAuNPs with biodegradable chitosan to form a chitosan-turmeric gold nanocomposite (NCS-TAuNPs). Phytochemical and gas chromatography-mass spectrometry (GC–MS) analysis were used to investigate the total phenolic and flavonoids contents, and chemical properties of the C. longa extract, assessment the antimicrobial and anti-biofilm efficiency of TAuNPs and NCS-TAuNPs conjugate against K. pneumoniae ESA254 and E. coli ESA253 isolates, evaluation in vitro, the cytotoxicity effects of TAuNPs and NCS-TAuNPs conjugate against MCF-7 cells and HCT-116 cancer cell lines copared with Fluorouracil (5FU) chemical anticancer drug. The results indicated that, presence of high levels (3452 mg QE/100 g DW and 2624 mg GAE/100 g DW) of flavonoids and phenolic contents in C. longa extract, the antioxidant scavenging abilities of 150 μg/mL of TAuNPs and NCS-TAuNPs conjugate against ABTS free radicals were reported 63.72 ± 0.09% and 52.55 ± 0.07% respectively, and 50.29 ± 0.038% and against DPPH free radicals were 68.43 ± 0.095% respectively. The maximum antibacterial activity by inhibiting K. pneumoniae ESA254 and E. coli ESA253 were recorded 15.6 ± 0.2 mm and 13.3 ± 0.20 mm at exposed to 150 µg/mL of NCS –TAuNPs, 14.3 ± 0.3 mm and 10.8 ± 0.23 mm by exposed to 150 µg/mL TAuNPs respectively. The maximum anti-biofilm activity (biofilm reduction %) of K. pneumoniae ESA254 and E. coli ESA253 were recorded 85.67 ± 2.46% and 77.50 ± 2.8% at exposed to 150 µg/mL of NCS –TAuNPs, 63.82 ± 1.89% and 58.07 ± 2.13% by exposed to 150 µg/mL TAuNPs respectively. The anticancer activity of TAuNPs and NCS–TAuNPs conjugate against MCF-7 and HCT-116 cell lines as cell viability %, showed potential cytotoxic effect in MCF-7 cells with IC50 values 38.77 ± 3.1 μg/mL and 36.31 ± 2.9 μg/mL exposed to 150 μg/mL of NCS–TAuNPs and TAuNPs respectively, and 41.26 ± 1.9 μg/mL and 39.85 ± 2.7 μg/mL in HCT-116 cell exposed to 150 μg/mL of NCS–TAuNPs and TAuNPs respectively. The study concluded that, the resulting biosynthesized TAuNPs and NCS–TAuNPs nanocomposite exhibited novel potential dual- anaotherapeutic efficiency combating MDR UTI pathogens and cancer treatment, the safe and biocompatible chitosan nanoconjugate is drug carriers with intelligent therapeutic platform, offering synergistic efficacy to AuNPs as anticancer and antibacterial agents against MCF-7 and HCT-116 cancer cell lines, against infections caused by K. pneumoniae and E. coli pathogens.

The online version contains supplementary material available at 10.1186/s13568-025-01953-y.