Optimized Biosynthesis of Bioactive Silver Nanoparticles-Kombucha Cellulose Nanocomposites

Strategic Insights -

Researchers from Sohag University have made a groundbreaking discovery in the field of nanotechnology, optimizing the biosynthesis of bioactive silver nanoparticles (AgNPs) integrated with nanofabricated kombucha SCOBY cellulose membrane (KC). This novel approach demonstrates potent antimicrobial activity against a range of pathogens, including E. coli, Bacillus subtilis, and Candida spp.

Key Takeaways:

  • The study achieved sustainable biosynthesis of monodisperse, bioactive silver nanoparticles (AgNPs) integrated with nanofabricated kombucha SCOBY cellulose membrane (KC) using the endophytic fungus A. fumigatiaffinis PP235788.1 fungal filtrate.
  • The AgNPs were optimized via full-factorial design of experiments (DOEs) and response surface methodology (RSM), identifying ideal conditions (2 mmol L-1 AgNO3, pH 8 and 60 °C).
  • Characterization revealed spherical AgNPs (14.50 ± 0.58 nm) and AgNPs@KC composites (17.88 ± 0.36 nm); SEM imaging demonstrates the successful fusion of AgNPs within KC's fibrous membrane, creating a seamlessly integrated nanocomposite with enhanced functional architecture.
  • The formed nanoparticles were composed of crystalline metallic silver, as varified by XRD (detected planes at 111, 200, and 220), and were stabilized by amide groups, as identified by FTIR spectroscopy.
  • The biosynthesized AgNPs demonstrated dose-dependent antimicrobial activity with an increase in inhibition zones from 11.8 ± 2.1 mm at 10 g/mL to 36.1 ± 0.4 mm at 100 g/mL for E. coli and from 9.8 ± 2.9 mm to 34.33 ± 1.2 mm for Bacillus subtilis.
  • Fungal pathogens displayed diminished sensitivity, with Aspergillus niger achieving maximum inhibition (25.7 ± 0.3 mm) at 100 g/mL, whereas Candida spp. necessitated 60 g/mL for observable inhibition zones.
  • AgNPs@KC composites demonstrated broad-spectrum efficacy against 12 pathogens (ANOVA, p < 95%), with maximal activity against E. coli, B. subtilis, and A. niger (33.0 ± 0.2 mm).

Statistics:

  • The optimized AgNPs achieved inhibition zones ranging from 11.8 ± 2.1 mm to 36.1 ± 0.4 mm for E. coli and from 9.8 ± 2.9 mm to 34.33 ± 1.2 mm for Bacillus subtilis.
  • AgNPs@KC composites demonstrated maximum activity against E. coli, B. subtilis, and A. niger (33.0 ± 0.2 mm).
  • The nanocomposites showed broad-spectrum efficacy against 12 pathogens, with an ANOVA p-value less than 95%.

Sources:

  • Optimized biosynthesis of bioactive silver nanoparticle-kombucha cellulose nanocomposites for enhanced antimicrobial applications. Applied Microbiology and Biotechnology, 2025,109(1):1-17.
  • NewsRx. Sohag University Researchers Discuss Findings in Nanoparticles (Optimized biosynthesis of bioactive silver nanoparticle-kombucha cellulose nanocomposites for enhanced antimicrobial applications). Nanotechnology Weekly. October 20, 2025; p 1974.