Azo dyes demonstrate dose-dependent carcinogenic and mutagenic effects in exposed
cells. Among remediation approaches, microbial adsorption is the most sustainable and
environmentally friendly method for eliminating azo dyes. A novel Aspergillus terreus silica
composite was developed as a sustainable adsorbent for crystal violet dye (CVD) removal.
The fungal strain was isolated from dye wastewater and was genetically identified by 18S
rRNA gene sequencing. Dried mycelia of A. terreus (PX920301) were combined with SiO2
(1:1 w/w) through iterative hydration-drying cycles, yielding a composite characterized by
FTIR analyses. Removal CVD %, adsorption capacity, and CVD residual were calculated,
and the adsorption process was optimized using Box–Behnken design (four factors, 25 runs).
The biosafety of the composite was assessed for phytotoxicity and microbial toxicity. The
composite was also applied to real dyes wastewater collected from the bacteriological
laboratory. Aspergillus terreus-silica composite showed the highest CVD removal percentage
by 85.4%, adsorption capacity (qe) 121.1 mg/L, and lowest CVD residual by 7.26 mg/L,
followed by the dried active mycelia (DA-mycelia) with CVD removal 40.23%, adsorption
capacity (qe) 57.05 mg/L, and CVD residual by 29.73 mg/L. Optimization data cleared that
the maximum experimental values of CVD removal (%) was 99.59% (predicted value 100%)
obtained in run number (4) using initial CVD concentration (200 mg/L), pH (8), adsorbent
composite weight (0.1 g), and contact time (48 h). Biosafety evaluation demonstrated
negligible phytotoxicity against Triticum aestivum seedlings post-treatment, with restored
germination and growth comparable to controls. Microbial toxicity assays via well-diffusion
to seven microbial isolates confirmed no toxic activities against the tested bacteria, yeast,
and fungi, underscoring the composite’s environmental safety. The composite could
decolorize the real dye wastewater of laboratories by 95.37%. In conclusion, A. terreus
mycelial-silica composite offers a cost-effective, sustainable, and eco-friendly alternative
solution for dye bioremediation.