Zinc oxide nanoparticles (ZnO NPs) are among the most frequently utilized nanomaterials because they inhibit

microbial growth; however, their precise mode of action (MOA) remains incompletely understood. This study

details the synthesis of zinc oxide (ZnO) nanoparticles via the sol-gel method, selected for its high purity,

homogeneity, and precise controllability. The research evaluates the impact of calcination temperature on the

structural, morphological, and antimicrobial properties of the resulting particles. Characterization was conducted

using X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Fourier-transform infrared spectroscopy

(FTIR) to determine crystallite size and surface composition. Additionally, the antifungal efficacy of the

synthesized ZnO nanoparticles was rigorously tested against Saccharomyces cerevisiae to assess their potential

The persistent degradation of both historical monuments and contemporary infrastructure caused by the

metabolic activity of microorganisms like fungi represents a major preservation challenge [1]. These biological

agents secrete secondary metabolites and allergenic compounds that compromise human health, contributing to

a rise in respiratory ailments and the prevalence of Sick Building Syndrome (SBS) [2,3].

Nanotechnology provides a sophisticated avenue for addressing these concerns, particularly through the use of

Zinc Oxide (ZnO) Nanoparticles (NPs). These particles are increasingly recognized for their dual functionality

as both antimicrobial agents and photocatalysts [2,4], making them an attractive option for developing protective

treatments for architectural surfaces. To improve the sustainability of these materials, recent research has focused

on the synthesis of metallic nanoparticles using plant extracts, which serve as eco-friendly alternatives to

[8], has emerged as a high-potential candidate in this field.

Research has shown that extracts from this plant are highly effective in synthesizing ZnO NPs when paired with

different precursors. For example, using zinc nitrate with the extract has been shown to refine the optical and

morphological characteristics of the particles [9], while the use of zinc acetate tends to boost their antimicrobial

potency [10,11]. The sol-gel technique is preferred for nanoparticle synthesis because it yields smaller diameters,

higher purity, and greater specific surface areas than other methods. It is particularly effective for producing

high-quality ZnO nanoparticles by allowing precise control over their shape, phase composition, and thermal

stability [12].

Recent research has focused on optimizing synthesis parameters to enhance ZnO performance across diverse

applications [13]. Through sol-gel processing, precursors like zinc acetate or zinc nitrate undergo hydrolysis and

antimicrobial potential of these nanoparticles.

Zinc Nitrate Hydrated (Zn (NO

O) and Gelatin powder was procured from from CDH Fine Chemicals.

ZnO nanopowder was synthesized via a sol-gel technique following the procedure (Ajay.K et.al. 2025) [15]. All

glassware (three-neck round bottom flask, measuring cylinder, and beaker) was cleaned, rinsed with distilled

For Antifungal test ZnO nanoparticle with NP size of 30 ± 15 nm were prepared using sol gel technique as

discussed above. Various concentration ZnOsuspensions were prepared in double distilled water which is

sonicated before its use in order to obtain uniform suspension. The different ZnO suspension concentration used

during the antifungal test are shown below in Table 1.

YPDA media is used for the antifungal test of Saccharomyces cerevisiae. The preparation protocol is shown

below. Amount of material used is described in the Table 2.

A specific quantity of yeast, peptone, and dextrose is introduced into a conical flask, followed by an equivalent

measure of water. The resulting mixture's pH is adjusted to 5.5 through the careful addition of a few drops of

contaminants. Finally, the sterile medium is combined with the desired quantity of a ZnO suspension, poured

the dried media is than kept under incubation for 24-72 hrs.

Transmission electron microscopy studies were carried out using a Hitachi H-7500. Thermogravimetric analysis

(TGA-DSC); Universal V4.1D TA instruments were used. FT-IR spectrum of ZnO nanoparticles were taken on

The characterization results of X-Ray diffraction pattern, FTIR spectroscopy, Thermogravimetric analysis and

TEM spectroscopy of the same ZNO nanoparticles were already discussed and reported in the previous study by

(Ajay.K et.al. 2025) [15].

and normal colony formation was observed. To assess the effect of ZnO NP on Saccharomyces Cerevisiae, the

yeast culture was inoculated by spreading on ypda plates containing different concentrations of ZnO NP which