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Article

Alkaline Mycoremediation: Penicillium rubens and Aspergillus fumigatus Efficiently Decolorize and Detoxify Key Textile Dye Classes

by
Magda A. El-Bendary
1,*,
Shimaa R. Hamed
2 and
Sayeda Abdelrazek Abdelhamid
2
1
Microbial Chemistry Department, Biotechnology Research Institute, National Research Centre, 33 Bohouth Street, Dokki, Giza 12622, Egypt
2
Microbial Biotechnology Department, Biotechnology Research Institute, National Research Centre, 33 Bohouth Street, Dokki, Giza 12622, Egypt
*
Author to whom correspondence should be addressed.
Sustainability 2026, 18(2), 921; https://doi.org/10.3390/su18020921
Submission received: 6 December 2025 / Revised: 9 January 2026 / Accepted: 13 January 2026 / Published: 16 January 2026
(This article belongs to the Section Sustainable Water Management)
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Abstract

Industrial synthetic dyes are among the most common and hazardous pollutants in manufacturing wastewater. In this study, effective dye-decolorizing fungi were isolated from industrial discharge and evaluated for their decolorization efficiency for various dyes, including a triphenylmethane (malachite green, MG), an anthraquinone (reactive blue 19, RB19), and an azo dye (reactive black 5, RB5). The fungus with the highest potential for MG decolorization was identified as Penicillium rubens, whereas Aspergillus fumigatus proved to be the most effective for RB19 and RB5 decolorization. Maximum decolorization for all dyes occurred at pH 9 and 30 °C after 6–7 days of shaking in the dark. Enzyme activity assays revealed that both P. rubens and A. fumigatus produced multiple oxidative and reductive enzymes, including laccase, azoreductase, anthraquinone reductase, triphenylmethane reductase, lignin peroxidase, manganese peroxidase, and tyrosinase. The decolorized filtrates of MG, RB19, and RB5 exhibited very low phytotoxicity for RB5 and no phytotoxicity for MG and RB19. Furthermore, these filtrates demonstrated significant reductions in chemical oxygen demand (46%, 63%, and 50%) and biological oxygen demand (37%, 60%, and 40%) for MG, RB19, and RB5, respectively, compared to untreated dyes. Given their efficient biological removal of dyes under alkaline conditions, these fungal isolates are promising candidates for sustainable wastewater treatment.

1. Introduction

Potable, clean water is becoming increasingly rare, partly because of aquatic environmental contamination caused by different industries [1]. Dyes have applications in various sectors, including textiles, rubber products, paper color, printing, and pharmaceuticals [2,3]. Industrial wastewater in aquatic environments contains approximately 10–15% of the used dyes, causing acute harmful effects on humans, aquatic plants, and ecosystems [4]. Dyes are classified according to their origin into natural and synthetic dyes [5]. Synthetic dyes, such as aromatic and heterocyclic dyes, and various chromophore groups, such as azo, carbonyl, nitro, autochrome, and quinoid groups, are more harmful than natural dyes [6,7]. The dye effluents discharge a variety of dangerous contaminants into the ecosystem, including critical indicators of contamination such as elevated COD and BOD [8,9]. The primary solution to this dilemma is the decolorization and detoxification of dyes using chemical, physical, and biological methods to discharge dye-free water [10]. Several physicochemical procedures are used to treat dye effluents; however, they are unsatisfactory owing to secondary hazardous byproducts, high costs, and restricted applications [11]. Biological techniques provide a sustainable alternative in terms of ease of use, affordability, fewer secondary byproducts, greater efficiency, and eco-friendliness [12]. Furthermore, most studies have focused on both fungi and bacteria for dye removal from contaminated water [13,14]. The most popular conventional adsorption method, activated carbon, relies on physical adsorption, where dyes are trapped on its surface but not degraded, creating a spent adsorbent that requires regeneration or disposal. Furthermore, activated carbon requires high-temperature and energy-intensive regeneration, with capacity loss over multiple cycles [15]. In contrast, biological methods, particularly those involving fungi, offer a sustainable alternative. These methods employ biosorption (onto fungal biomass) coupled with enzymatic biodegradation by extracellular enzymes produced by fungi. They cleave and mineralize complex dye structures, potentially leading to complete detoxification without generating hazardous sludges. Furthermore, fungal biomass is biodegradable and can potentially be composted or used as a soil amendment. Therefore, fungal degradation of dyes is a sustainable, environmentally safe, and cost-efficient method [16].
Fungi are widely known for their capacity to degrade synthetic pigments through enzymatic processes, making them promising candidates for bioremediation. However, most fungal species exhibit optimal dye degradation in acidic environments (pH 4–6), limiting their efficiency in alkaline conditions (pH > 7), where many industrial dyes are discharged [17]. This presents a significant drawback because textile effluents rich in synthetic dyes are often alkaline (pH 8–11) owing to the use of alkaline chemicals in the textile dyeing procedures. While some fungi, such as Aspergillus niger, can adapt to mild alkalinity, their degradation rates decline sharply compared to acidic conditions. Thus, the reliance on acidic pH restricts the practical application of fungi in treating industrial wastewater unless pH adjustments are made, which increases costs and complexity [18]. Temperature, dye concentration, illumination, pH, and aeration are critical factors that affect the efficacy of microbial dye degradation [2,7]. Enzymes are extremely successful in dye degradation because of their high selectivity and catalytic activity [17,19,20]. Manganese and lignin peroxidases are heme-containing glycoproteins that catalyze the oxidation of aromatic polycyclic hydrocarbon materials [21]. Azoreductases are essential for breaking down bright synthetic azo dyes by cleaving their characteristic (–N=N–) bond in the presence of reducing agents such as NADH and NADPH [22]. Tyrosinases are oxidation enzymes that catalyze the oxidation of aromatic molecules without the use of cofactors [23]. Laccases are copper-containing oxidase enzymes that oxidize various aromatic compounds by removing electrons from substrates and transferring them to oxygen, reducing it to water [24].
While fungal bioremediation of dyes is a well-established field, the vast majority of studies have focused on acidic to neutral pH conditions. This study presents an efficient and sustainable dye decolorization method under alkaline conditions. This is critical because many industrial dye effluents, particularly those from textile processing, are inherently alkaline. The aim of the current study was to investigate the efficiency of fungal isolates as dye-decolorizing bio-agents under alkaline conditions. Simultaneously, the optimization of the growth physical parameters for dye decolorization was studied. Oxidoreductive enzymes produced by the promising fungi were tested. Additionally, the phytotoxicity, chemical, and biological oxygen demands of the decolorized solutions were investigated.

2. Materials and Methods

2.1. Chemicals

Reactive blue 19 (RB19) and reactive black 5 (RB5) were kindly gifted by the Dyeing, Printing, and Textile Auxiliaries Department at the National Research Centre of Egypt. Malachite green (MG) was purchased from Oxford Fine Chem Lap (Oxford, UK). The characters of these dyes are recorded in Table 1. These dyes were used as received without further purification. Guaiacol was obtained from GmbH & Co. KG, (Frankfurt, Germany) and NADH was from Park Scientific Limited, (Northampton, UK). Catechol, syringaldazine, n-propanol, tartaric acid, and H2O2 were acquired from Sigma-Aldrich (Burlington, MA, USA). All other chemicals were of analytical grade.

2.2. Isolation of Dyes Degrading Fungi

Dyed wastewater samples of Cloverbrook Textile Company, Cairo, Egypt, were collected and subjected to fungal isolation according to the method of Fouda et al. [25] with some modifications. These samples were serially diluted using 0.85% NaCl and inoculated on Czapek–Dox agar plates, which contained (g/L) glucose (30), NaNO3 (3), KCl (0.5), MgSO4.7H2O (0.5), K2HPO4 (1), FeSO4.7H2O (0.01), and for solidification 15g/L agar was added. These plates were incubated at 30 °C for 5 days. The fungal colonies were collected and sub-cultured on Czapek–Dox agar to obtain pure fungal cultures. Each pure fungal organism was cultured on a Czapek–Dox agar slant.

2.3. Screening Dye Decolorization Efficiency of the Isolated Fungi

The decolorization activity of the tested fungi was assessed according to Robinson et al. [26]. Tested fungal isolates were cultivated in 250 mL Erlenmeyer flasks containing 100 mL of Czapek–Dox medium supplemented separately with 50 mg/L of each tested dye (MG, RB19, and RB5). They were incubated at 30 °C for 5 days under shaking (120 rpm) and dark conditions. The cultures were centrifuged for 10 min at 5000 rpm. The supernatants were spectrophotometrically analyzed using a JASCO V-630 spectrophotometer, JASCO Corporation (Hachioji, Japan) at the λmax of each dye. Blank dye controls (without inoculum) were run simultaneously under the same conditions. The decolorization percentage was calculated using Equation (1) based on Roy et al. [27]:
Decolorization (%) = (A − B)/A × 100
where A and B represent the absorbance of the solution prior to and following the fungal dye decolorization, respectively.

2.4. Identification of the Fungal Isolates

All isolated fungi have been identified according to their morphological and microscopic features using an optical light microscope (Olympus CH40, Olympus Corporation, Tokyo, Japan) in accordance with the following references: Ainsworth as a dictionary of the fungi [28,29] for a synoptic key to the Aspergillus nidulans group and Emericella species; Klich et al. [30] for Aspergillus species; and Ramirez; Pitt, and Pitt et al. [31,32,33] for Penicillium species.
The promising dye-removing fungi (two isolates) were molecularly identified. The tested isolates were cultured in Czapek–Dox medium for 4 days. After culture growth, the mycelia were filtered and washed with distilled water, and used for genomic DNA extraction according to Sharma et al. [34]. Primers ITS1 5′-TCCGTAGGTGAACCTGCGG-3′ and ITS4 5′-TCCTCCGCTTATTGATATGC-3′ were used for amplification of the ITS region of the fungal ribosomal DNA (rDNA). The PCR reaction began with an initial 10 min denaturation at 95 °C, followed by 30 cycles of 92 °C for 50 s, 55 °C for 70 s, and 72 °C for 60 s each, with a final 10 min step at 72 °C. The amplified products were purified using Millipore Corp.’s gel extraction kit (Bedford, MA, USA). The sequencing reaction was performed using PRISM Big Dye Terminator v3.1 Cycle Sequencing Kit (Thermo Fisher Scientific, Waltham, MA, USA) and analyzed using an ABI Prism 3730XL DNA analyzer (Applied Biosystems, Foster City, CA, USA). The sequences were examined via the BLAST database from NCBI (http://www.ncbi.nlm.nih.gov/BLAST (accessed on 14 March 2024)). The independent Pair Group Method and Neighbor-Joining using Molecular Evolutionary Genetics Analysis (MEGA ver. 12) were used to generate a phylogenetic tree based on the ITS region of rDNA registered in NCBI [35]. The ITS sequences of the isolated fungi were deposited in GenBank and allocated an accession number by NCBI.

2.5. Optimization of the Dye Decolorization Process

The promising fungal cultures were subjected to different physicochemical conditions to determine their effect on the dye decolorization efficiency. Different factors were studied as the effect of pH of the medium (5, 6, 7, 8, 9, and 10), dye concentration (40, 50, 75, and 100 mg/L), incubation period (3, 4, 5, 6, and 7 days), temperatures (25, 30, 35, and 40 °C), and inoculum size (0.5%, 1%, 1.5%, and 2%). Also, the effect of shaking, static, light, and dark conditions was studied. The experiments were carried out in triplicate.

2.6. Fungal Extracellular and Intracellular Enzyme Preparation

The extracellular and intracellular enzymes generated by the tested fungal species have been extracted employing the methods described by Lade et al. [36] with some modifications. Each culture was cultivated in two distinct batches of 250 mL Erlenmeyer flasks. The first batch contains Czapek–Dox medium (50 mL), while the second batch contains Czapek–Dox medium supplemented with 50 mg/L dye. The two batches were inoculated and incubated at 120 rpm and 30 °C for 7 days. After that, the mycelia and the filtrates were separated by centrifugation at 5000 rpm for 10 min. The supernatants were used as extracellular enzyme sources. The mycelia were washed two times and resuspended in phosphate buffer (50 mM, pH 7) and sonicated with 8 strokes for 40 s each for 2 min intervals with 60 amplitude output at 4 °C. The resulting suspensions were centrifuged at 5000 rpm for 10 min, and the supernatant was employed as the intracellular enzyme source.

2.7. Oxidative and Reductive Enzymes Analysis

The activities of different extracellular and intracellular oxidoreductive enzymes have been evaluated spectrophotometrically.

2.7.1. Oxidative Enzymes Analysis

Laccase, tyrosinase, lignin peroxidase (LiP), and manganese peroxidase (MnP) were analyzed as oxidative enzymes.
Laccase activity was tested using guaiacol according to El-Bendary et al. [37] with minor modifications. The reaction mixture contains the filtrate (0.4 mL) and 1.6 mL guaiacol (10 mM in phosphate buffer, 50 mM, pH 7). The mixture was incubated at 30 °C for 30 min, then put in an ice bath for 15 min to stop the reaction. The samples were spectrophotometrically measured at 470 nm. An extinction coefficient of 6740 M−1cm−1 was used for calculating the enzyme units.
Tyrosinase activity was evaluated according to Lade et al. [36]. A three mL reaction mixture contained 0.1 mL of 50 mM catechol, 0.1 mL of 2.1 mM L-ascorbic acid in phosphate buffer (50 mM, pH 7), and 0.1 mL of enzyme solution was incubated at 30 °C. A decrease in optical density at 265 nm indicates the formation of dehydro-ascorbic acid and o-benzoquinone. An extinction coefficient of 2200 M−1 cm−1 was used for the calculation of the enzyme activity.
LiP was determined by the formation of propanaldehyde at 300 nm as recorded by Jadhav and Govindwar [38]. The reaction mixture (2.5 mL) containing 100 mM of n-propanol, 250 mM of tartaric acid, 10 mM of H2O2, and 0.5 mL of the enzyme was incubated for 10min at 30 °C. The reaction was stopped in an ice bath, and the optical density was recorded at 300 nm. An extinction coefficient of 9300 M−1cm−1 was used for the calculation of the enzyme activity.
MnP activity was measured at 270 nm according to Jarvinen et al. [39]. The reaction mixture contained 0.5 mM MnSO4 in sodium malonate buffer (50 mM, pH 4.5), 0.5 mL of the tested enzyme solution, and H2O2 (0.1 mM). The reaction was followed for 30 s at 30 °C. An extinction coefficient of 11,590 M−1cm−1 was used for unit calculation.

2.7.2. Reductase Enzymes Analysis

The reductase dye decolorizing enzyme activity, such as MG reductase (triphenylmethane reductase), RB19 reductase (anthraquinone reductase), RB5 reductase (azoreductase), and NADH-DCIP reductase (azoreductase), was assessed as reported by Salokhe and Govindwar [40] by changing the DCIP with different dyes. In general, the reaction mixture (2 mL) contains 25 µM of DCIP or 2 µg of each tested dye dissolved in phosphate buffer (50 mM, pH 7), 0.2 mL of enzyme, and 250 µM of NADH, and was incubated for 5 min at 30 °C. The decrease in optical density was determined at 590 nm, 620 nm, 595 nm, and 597 nm for determining the absorbance decrease in DCIP, MG, RB19, and RB5, respectively. The reductases of DCIP, malachite green, reactive blue 19, and reactive black 5 were calculated by using the molar extinction coefficient of 19,000 M−1 cm−1, 8400 M−1cm−1, 6258 M−1cm−1 and 35,500 M−1cm−1, respectively.
Enzyme activity was expressed as U/mL and calculated using Equation (2):
EA = (A × V)/(t × e × v)
where EA is enzyme activity (U/mL); A is absorbance at a specific wavelength; V is reaction mixture volume (mL); v is enzyme volume (mL); t is incubation time (min); and e is molar extinction coefficient. One unit of enzyme activity is the enzyme amount required to oxidize/reduce 1 µmol of substrate or produce 1 µmol of product in one min under testing conditions.

2.8. Phytotoxicity Test

The phytotoxicity test was used to determine the acute toxicity of the various dyes tested before and after fungal degradation. Lentil seeds were used for the test in triplicate. For each dye, two sets of 10 lentil seeds in Petri dishes containing cotton pads were treated as follows: one set was watered with 5 mL of the tested dye (50 mg/L for MG and 100 mg/L for RB19 and RB5). The second set was watered with 5 mL of the fungal supernatant after dye decolorization. Under the same circumstances, a control set that was watered with tap water also operated concurrently. After seven days, the phytotoxicity was assessed in terms of the percentage of germination and the length of the plumule and radicle. The following formula was used to calculate the rate of germination index, relative root elongation, relative seed germination, and germination index [41]:
Relative seed germination (SG %) = Number of seeds germinated in the treated group/Number of seeds germinated in the control group × 100
Relative root elongation (RE %) = mean root elongation in the treated group/mean root elongation in the control group × 100
Relative shoot elongation (SE %) = mean shoot elongation in the treated group/mean shoot elongation in the control group × 100
Germination index (GI) = SG% × RE%/100.
GI values less than 50% are highly phytotoxic, GI values between 50 and 80% are low phytotoxic, and GI values more than 80% are non-phytotoxic.

2.9. Determination of COD and BOD

COD and BOD were determined before and after fungal decolorization for the various tested dyes at 50 mg/L for MG and 100 mg/L for RB19 and RB5. COD determination was carried out using the 5220 D technique [42] while BOD measurement was carried out using the 5210 B technique [43].

2.10. Statistical Analysis

Data obtained from this study were statistically analyzed according to the SPSS statistics version 22 using one-way analysis and Duncan’s multiple range test to determine the significance between means. Data were expressed as mean values ± standard errors (SE). p ≤ 0.05 revealed a significant difference.

3. Results and Discussion

The textile industry releases huge amounts of wastewater stained with organic pigments and toxic heavy metals. Compared to traditional physicochemical-based methods, fungal-based bioremediation for dye wastewater provides significant benefits, including detoxification of textile dyes and other hazardous chemicals in an eco-friendly manner [44].

3.1. Fungal Isolation and Their Dye Decolorization Efficiency

Fourteen fungal candidates were obtained from the textile industry’s dye wastewater. The isolated fungi, as shown in Table 2, were identified by microscopic examination, and they belonged to four genera: Aspergillus, Penicillium, Absidia, and Rhizopus. The results, as given in Table 2, revealed that four fungal isolates can decolorize MG (SRH9, SRH12, SRH13, and SRH14) with the maximum by SRH14, whereas seven can decolorize RB19 (SRH1, SRH2, SRH3, SRH9, SRH11, SRH12, and SRH14) with the maximum by SRH9. RB5 was decolorized by four fungal isolates (SRH1, SRH5, SRH9, and SRH11), with the maximum by SRH9. SRH14 exhibited the most MG decolorization (55%), while SRH9 had the most RB19 and RB5 decolorization (58% and 59%), respectively (Table 2 and Figure 1). Therefore, these isolates (SRH14 and SRH9) were molecularly identified and selected for dye decolorization optimization.

3.2. Identification of the Promising Dye Decolorizing Fungi

Morphologically, SRH14 colonies were light green on the CYA medium, with a diameter of around 28 mm after 4 days of incubation. Conidiophores are classified as “terverticillata,” and they have one to three branches situated between the metulae and the stipe. While SRH9 grown on CYA developed a velvety, blue–green tint with a short white border and a white to pale yellowish reverse. Microscopic inspection revealed green conidia generated in chains identified by greenish phialides; the vesicles are subclavate, with lactophenol cotton blue.
Molecularly, the nucleotide sequences of the ITS region of rDNA of the two isolates (SRH14 and SRH9) were detected. The phylogenetic tree was structured by the method based on ITS sequences registered in NCBI. ITS region of rDNA sequence analysis showed that SRH14 and SRH9 are closely related to P. rubens and A. fumigatus, respectively. The phylogenetic analysis of the sequences of P. rubens and A. fumigatus is shown in Figure 2a,b, respectively. ITS sequences of P. rubens and A. fumigatus were deposited in the GenBank under accession numbers of PP484940.1 (http://www.ncbi.nlm.nih.gov/nuccore/PP484940.1 (accessed on 14 March 2024)) and PP484878.1 (http://www.ncbi.nlm.nih.gov/nuccore/PP484878.1 (accessed on 14 March 2024)), respectively.
Many fungi were reported as potential dye bio-decolorizing organisms, such as Penicillium sp., Aspergillus niger, Aspergillus sojae, Pycnoporus cinnabarinus, Ganoderma sp., Ceriporia metamorphosa, Trichoderma sp., Bjerkandera adusta [20], Peyronellaea prosopidis, Aspergillus flavus, Coriolopsis sp., Aspergillus bombycis, Scheffersomyces spartinae, Ceriporia cerata, Cerrena sp., Phanerochaete chrysosporium, Pleurotus ostreatus, Myceliophthora vellerea, Pichia sp. [18], Phanerochaete velutina, Trametes versicolor, Ganoderma lucidum, Perenniporia subtephropora, Ganoderma sp., and Pleurotus eryngii [17].

3.3. Optimization of Fungal Growth Conditions for Dye Decolorization

Growth parameters that involve pH, incubation period, temperatures, dye concentration, inoculum size, aeration, and illumination all have a significant effect on microbial growth, enzyme synthesis, and subsequently dye decolorization [2,45].

3.3.1. Effect of pH

pH is one of the most significant factors that influence the dye decolorization and other biological activities [1]. As shown in Figure 3, Czapek–Dox medium at pH 9 showed the maximum dye decolorization of MG by P. rubens, and RB19 and RB5 by A. fumigatus, respectively. The finding that P. rubens and A. fumigatus obtained maximum decolorization of tested dyes at pH 9 in Czapek–Dox medium is especially significant because it contradicts the typical acidic pH preference observed for most dye-decolorizing fungi. A good decolorization at alkaline pH suggests tremendous potential for biotechnological applications, particularly in the remediation of alkaline textile effluent.
After dyeing, bioremediation of wastewater from textile factories requires the use of alkalophilic microorganisms that can thrive in harsh conditions. Certain Aspergillus species exhibit remarkable alkalotolerance and possess the enzymatic machinery (e.g., alkaline-stable laccases, peroxidases, and azoreductases) necessary for efficient decolorization of a wide range of synthetic dyes under alkaline conditions (>pH 7). This unique adaptation is not universal among fungi, but it is a major biotechnological feature for isolated A. fumigatus, making it a promising candidate for the bioremediation of alkaline dye-wastewater without requiring pH neutralization [46,47]. It was reported that the dye decolorization activity by A. niger was the maximum at pH 6 [48,49]. In the same trend, Khan et al. [45] found that Remazol Brilliant Blue (RBB) dye decolorization using A. fumigatus and A. terreus showed a maximum of 99% at acidic pH, while the lowest decolorization was obtained under alkaline pH conditions.
It was reported that a high alkaline or acidic pH can reduce the dye decolorization rate. The functional groups, such as hydroxyl and carboxyl groups, which are produced as a result of medium pH, affect the microbial biomass surface charge. These functional groups serve as dye adsorbing sites. The wastewater released from textile manufacture is usually alkaline; therefore, the isolation of fungi that can grow and decolorize dyes in this alkaline pH is particularly promising [50].

3.3.2. Effect of Dye Concentration

As shown in Figure 4, P. rubens decolorized MG at 50 mg/L by 80%. At higher concentrations of MG (75 and 100 mg/L), the decolorization sharply decreased to 31% and 25%, respectively. While A. fumigatus showed high decolorization of RB19 and RB5 at 50–100 mg/L. These findings contradict Khan et al. [45], who reported that A. terreus and A. fumigatus exhibited maximum decolorizations of 40 mg/L RBB (azo dye), while no decolorization was obtained at 100 mg/L RBB. Also, Ramya et al. [51] found that 82%, 88%, and 93% decolorization of Acid-Red 151 by A. niger SA1, A. terreus SA3, and A. flavus SA2 was obtained at 50 mg/L, respectively.
It was reported that the concentration of dyes significantly affects their degradation by microorganisms [52]. The presence of dyes at hazardous quantities can impact microbial growth, as well as dye decolorization and degradation efficiency, by blocking enzyme active sites and decreasing enzyme activity [17,18,53]. Rajhans et al. [18] concluded that increasing dye concentration per unit volume suppressed fungal growth due to increased stress, reduced enzyme activities, and decreased their degradation efficiency.

3.3.3. Effect of Incubation Period

The incubation period varies significantly based on the type of growth medium and the specific microorganisms used in the decolorization procedure. Also, it is a fundamental parameter that governs the kinetics and pathway of microbial dye degradation. The effect of the incubation period on fungal dye degradation is a critical and complex aspect [52]. As shown in Figure 5, the decolorization percent of all tested dyes gradually increased with increasing the incubation period from 3 days to 7 days, reaching about 95–97% on the 7th day. Similarly, Khan et al. [45] found that the best incubation time was 5 days for A. fumigatus and A. terreus for decolorization of RBB. Furthermore, de Almeida et al. [54] reported that Phanerochaete chrysosporium strain ME-446 could decolorize three azo dyes (RRB5, direct yellow 27, and reactive red 120) after 10 days of incubation.
While the fungal decolorization process demonstrates exceptional biological efficacy at the lab scale, its engineering limitations concerning reaction time and operational mode constrain its application as a stand-alone, full-scale solution. However, its true potential lies in its strategic integration as a specialized pretreatment step. By adapting the process objectives towards rapid partial degradation/detoxification and advancing research in bioreactor engineering and immobilization, this technology can evolve into a sustainable and cost-effective unit process.

3.3.4. Effect of Temperature

Temperature was a crucial factor in decolorization efficiency since it influenced microbial proliferation and enzymatic activity [55]. As shown in Figure 6, the maximum dye decolorization by the tested fungi was at 30 °C for MG (95%) and RB5 (97%) by P. rubens and A. fumigatus, respectively. Raising the incubation temperature to 35 °C and 40 °C significantly reduced MG decolorization by about 47% and 61%, and RB5 decolorization by approximately 51% and 62%, respectively. A. fumigatus demonstrated strong decolorization for RB19 at temperature ranges from 25 °C to 35 °C (95–99%), with a substantial drop of about 24% at 40 °C. Ergene et al. [56] demonstrated that A. flavus and Helminthosporium sp. could decolorize RBB by 95% and 75%, respectively, at 37 °C. Das et al. [50] found that RB5 decolorization increased as the temperature increased from 30 °C to 40 °C; however, it decreased to 43% at 45 °C. On the other hand, Karaca et al. [55] reported that the optimal temperature for reactive blue 13 decolorization by Sporotrichum sp. was at 20 °C.
It was reported that the temperature has a direct effect on fungal growth, degradative enzyme synthesis, and enzyme stability. It was found that increasing the temperature enhanced the rate of color removal of dyes until a certain point was reached, at which point dye decolorization decreased. This could be attributed to an increase in enzyme activity as the temperature rises to a certain point, after which further temperature increases reduce decolorization effectiveness due to enzyme denaturation [50].

3.3.5. Effect of Inoculum Size

The effect of inoculum size on the decolorization of different dyes by fungal isolates is shown in Figure 7. The increase in the inoculum size from 0.5% to 2% showed no significant difference in the decolorization of the tested dyes by the tested organisms. In contrast to these findings, Yusuf et al. [57] found that the percentage of Congo red decolorization was enhanced with a greater amount of A. quadrilineatus inoculum size.
The observation of no significant difference in dye decolorization with inoculum size is a powerful indication. It suggests that the process is not merely a function of biomass but is governed by the induced physiological state of the fungus and the kinetic parameters of its enzyme system.

3.3.6. Effect of Shaking and Stationary Conditions on Dye Decolorization

It is quite clear from the data in Figure 8 that there is a noticeable difference between shaking and static incubation on the decolorization of different dyes. The decolorization of MG, RB19, and RB5 increased from 42.7, 25, and 65% under static conditions to 91, 95, and 96% under shaking conditions, respectively. Shaking cultures have been shown to remove more color than static cultures because of improved oxygen transport and nutrient distribution [58]. Similar findings were reported by Rigas and Dritsa [59], who found that basidiomycetes strains exhibited higher Poly R-478 removing efficiency under shaking conditions as compared to static conditions. Also, Martínez-Trujillo et al. [60] reported that the shaking increases Trametes versicolor’s ability to remove the RB5 dye. In contrast to these findings, Ali et al. [61] reported that the highest decolorization percentage of azo dyes by Penicillium spp., Alternaria spp. SA4 and A. flavus SA2 were under static conditions compared with shaking conditions. Also, Bettin et al. [62] studied the decolorization of 22 different dyes using Pleurotus sajor-caju PS-2001 laccases and found that the decolorization efficiency was much lower with agitation than that obtained under stationary conditions.
It is hypothesized that reductase activity can be stimulated under anaerobic conditions, whereas aerobic dye degradation requires oxidative enzymes that require oxygen [18].

3.3.7. Effect of Illumination

The dye decolorization by the tested fungi was more efficient in dark conditions than in illuminated conditions, as shown in Figure 9. P. rubens could decolorize 95% of MG under dark conditions in comparison to 43% decolorization under illuminated conditions. Also, A. fumigatus could decolorize RB19 and RB5 about 98% and 95%, under dark conditions in comparison to 64% and 53% decolorization under light conditions, respectively. Typically, Gomaa et al. [63] reported that Phanerochaete chrysosporium could decolorize various textile dyes under dark conditions, avoiding dye polymerization under illumination. Perhaps the dark conditions provide a stable, stress-free environment that allows the complex enzymatic machinery of the fungi to operate at its maximum efficiency.

3.4. Enzyme Analysis

Microbial enzymes play a major role in the biological degradation of dye substances [64]. As shown in Table 3, in general, all the tested fungal isolates showed laccase, MnP, LiP, tyrosinase, RB19 reductase, RB5 reductase, MG reductase, and NADH-DCIP reductase activities.
For P. rubens, the following enzymes are more active in the filtrate without a dye: exo-laccase, endo-laccase, endo-LiP, exo-MnP, exo-RB5 reductase, endo-RB5 reductase, and exo-NADH-DCIP reductase. At the same time, the activity values of exo-LiP, endo-MnP, exo-tyrosinase, exo-MG reductase, endo-MG reductase, exo-RB19, and endo-RB19 are higher in the medium containing MG dye. The activities of endo-tyrosinase and endo-NADH-DCIP reductase are the same in both exo- and endo- filtrates.
For A. fumigatus with RB19, the enzyme activities of exo-laccase, endo-tyrosinase, exo-MG reductase, exo-RB19 reductase, endo-RB19 reductase, and endo-NADH-DCIP reductase are much better in the medium without dye. While endo-laccase, exo-LIP, endo-LIP, exo-MnP, endo-MnP, exo-tyrosinase, endo-MG reductase, and endo-RB5 reductase are more active in the presence of RB19 dye. In the case of exo-RB5 reductase and exo-NADH-DCIP activities in both tested filtrates are nearly the same.
For A. fumigatus with RB5, the activities of exo-laccase, endo-laccase, endo-tyrosinase, exo-MG reductase, endo-RB19 reductase, exo-NADH-DCIP reductase, and endo-NADH-DCIP reductase in the medium without RB5 dye are more than those with RB5. On the other hand, exo-LiP, endo-LiP, exo-MnP, endo-MnP, exo-tyrosinase, endo-MG reductase, exo-RB19 reductase, exo-RB5 reductase, and endo-RB5 reductase increased in the medium with RB5 dye.
It has been reported that enzymes such as laccases, azoreductase, LiP, MnP, and hydroxylases are active during microbial breakdown of azo dyes [65]. Also, A. fumigatus, A. terreus, and A. tamarii were found to have LiP and MnP activities in the degradation of anthraquinone dye [45,66]. The laccase production by many fungal strains is associated with dye degradation, such as Phanerochaete chrysosporium, Pleurotus sp., and Phlebia radiata [67]. Most of these fungi that produce laccase belong to Basidiomycetes [68], and a few strains are reported from Deuteromycetes and Ascomycetes [69]. Furthermore, Chatterjee and Pandey [70] claimed that the two species, Fusarium foetens and A. costaricaensis, as laccase enzyme producers, could be used as significant agents in the degradation of complex fabric dyes. Azoreductases are the most common enzymes detected in the breakdown of azo dyes. They are intracellular or extracellular enzymes that catalyze the breakage of azo linkages to produce colorless aromatic amines [71]. Several azoreductases from various fungi have been identified, and they require the presence of NADH or NADPH to function as reported by Cong et al. [72]. It is known that tyrosinases are often related to spore production and stability, defense and virulence mechanisms, and pigmentation in fungi [73]. They catalyze the oxidation of aromatic molecules, including phenolic compounds. This enzyme stimulates the oxidation of monophenol o-hydroxylation to o-diphenols, then o-diphenol oxidation to o-quinone [74].
It was reported that Saccharomyces cerevisiae MTCC 463 decolorized methyl red in a static environment. The enzymes involved in methyl red decolorization were azoreductase, laccase, peroxidase, and NADH-DCIP reductase [50].
The combination of various enzymes, including laccase, azoreductase, oxidoreductase, and others, can significantly enhance the biodegradation of textile dyes.

3.5. Phytotoxicity

Untreated waste dye water has a significant health and environmental impact. Considering that this water can be utilized for plant irrigation, it is critical to evaluate the dyes’ phytotoxicity before and after the decolorization technique. As shown in Table 4, the seeds were watered with 50 mg/L of MG, 100 mg/L of RB19, or 100 mg/L of RB5, revealing high phytotoxic effects, especially with RB19 and RB5. However, the treated dye solution by tested fungi considerably increases the germination of seeds, percentage shoot and root lengths, and germination index, indicating that the degraded dye in the solution generated after fungal treatment has less/no toxicity on the plant. The solution after fungal decolorization of dye showed a superior increase in the germination index from 48% to 96% for the MG solution and from 7.2% to 154% for the RB19 solution, indicating the non-phytotoxicity after dye treatment. A GI value over 100% indicates stimulation or beneficial effects on seed germination and sprouting. Also, treatment of RB5 dye with RSH9 showed an increase in germination index from 6.4% to 58%, indicating low toxicity of the solution. These results are similar to the study of Yan et al. [4], who used P. janthinellum LM5 for the treatment of Congo red solution and found that the treated dye solution had no influence on plumule and radicle germination and development, demonstrating its effective and environmentally benign approach for dye removal with fungal growth. Also, Abd-Elrahim et al. [75] reported that the Direct Red 81 solutions treated by Penicillium spp., Aspergillus spp., and Trichoderma sp. were non-phytotoxic to Vicia faba, Trigonella foenum-graecum, or Lens culinary. Ghanaim et al. [16] concluded that the degraded products after treatment of azo dyes and malachite green solutions using Aspergillus flavus were less harmful to the germination rates and growth of bean and maize plants.

3.6. COD and BOD

COD and BOD levels serve as essential indicators for evaluating the degree of aquatic environment pollution, and reducing them means pollutant degradation [76]. The filtrates of Czapek–Dox broth amended with MG, RB19, and RB5 after decolorization by tested fungi showed a reduction in their COD and BOD, as shown in Table 5. A reduction in COD was about 46%, 63%, and 50% for MG, RB19, and RB5, respectively. A reduction in BOD was about 37%, 60%, and 40% for MG, RB19, and RB5, respectively. Observing a reduction in both COD and BOD after fungal treatment of dye solutions is a strong indicator that the tested fungi are performing effective biodegradation. They are not just removing color but are actively breaking down the polluting organic compounds, reducing the overall oxygen demand of the effluent, and improving its compatibility with the natural environment or further treatment stages [44].

4. Conclusions

This study establishes the significant potential of two locally isolated fungal strains, Penicillium rubens and Aspergillus fumigatus, as robust and sustainable biocatalysts for the bioremediation of textile wastewater under alkaline conditions. At pH 9.0 and 30 °C, P. rubens efficiently decolorized the triphenylmethane dye (MG) by 95%, while A. fumigatus decolorized the anthraquinone dye (RB19) and the azo dye (RB5) 5 by 98 and 95%, respectively. This high efficiency under alkaline conditions highlights their direct sustainable applicability for treating real textile effluents. Dye removal was mediated by a complementary extracellular oxidoreductive enzyme system (laccase, MnP, LiP, tyrosinase, and Mg, RB19, RB5, and DCIP reductases), enabling the degradation of structurally diverse chromophores. Importantly, the process achieved substantial detoxification, as confirmed by phytotoxicity assay, and significantly reduced the organic pollutant load, with COD and BOD reductions of up to 37–63%. Finally, P. rubens and A. fumigatus represent promising eco-friendly candidates for advancing sustainable mycoremediation strategies. Their alkaliphilic nature, multi-enzyme degradation capacity, and no/low phytotoxicity offer a viable green alternative to conventional textile wastewater treatments. Future studies should focus on elucidating degradation pathways and developing scalable bioreactors or in situ applications to support sustainable industrial wastewater management.

Author Contributions

M.A.E.-B.: conceptualization, methodology, formal analysis, investigation, writing—original draft preparation, review, and editing of the final manuscript. S.R.H.: conceptualization, methodology, formal analysis, investigation, writing—original draft preparation, review, and editing of the final manuscript. S.A.A.: conceptualization, methodology, formal analysis, investigation, writing—original draft preparation, review, and editing of the final manuscript. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The raw data supporting the conclusions of this article will be made available by the authors on request.

Acknowledgments

The authors thank and appreciate the National Research Centre of Egypt for its technical and moral support.

Conflicts of Interest

The authors declare no conflicts of interest.

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Figure 1. Dye degradation by isolated fungi: (a,b) MG before and after decolorization by Penicillium rubens; (c,d) RB19 before and after decolorization by Aspergillus fumigatus; (e,f) RB5 before and after decolorization by Aspergillus fumigatus.
Figure 1. Dye degradation by isolated fungi: (a,b) MG before and after decolorization by Penicillium rubens; (c,d) RB19 before and after decolorization by Aspergillus fumigatus; (e,f) RB5 before and after decolorization by Aspergillus fumigatus.
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Figure 2. Phylogenetic neighbor-joining trees of the partial sequence of the ITS region of the rDNA gene, showing the relative phylogenetic position of isolated (a) Penicillium rubens, and (b) Aspergillus fumigatus with respect to closely related sequences available in the GenBank databases. The red color refers to the isolated fungi.
Figure 2. Phylogenetic neighbor-joining trees of the partial sequence of the ITS region of the rDNA gene, showing the relative phylogenetic position of isolated (a) Penicillium rubens, and (b) Aspergillus fumigatus with respect to closely related sequences available in the GenBank databases. The red color refers to the isolated fungi.
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Figure 3. Effect of growth medium pH on the dye decolorization by tested fungi (50 mg/L dye, 30 °C, 1% inoculum size, 5 days of incubation under shaking and dark conditions).
Figure 3. Effect of growth medium pH on the dye decolorization by tested fungi (50 mg/L dye, 30 °C, 1% inoculum size, 5 days of incubation under shaking and dark conditions).
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Figure 4. Effect of different dye concentrations on the dye decolorization by tested fungi (pH 9, 30 °C, 1% inoculum size, 5 days of incubation under shaking and dark conditions).
Figure 4. Effect of different dye concentrations on the dye decolorization by tested fungi (pH 9, 30 °C, 1% inoculum size, 5 days of incubation under shaking and dark conditions).
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Figure 5. The effect of the incubation period on the dye decolorization by the tested fungi (50 mg/L dye, pH 9, 30 °C, 1% inoculum size, under shaking and dark conditions).
Figure 5. The effect of the incubation period on the dye decolorization by the tested fungi (50 mg/L dye, pH 9, 30 °C, 1% inoculum size, under shaking and dark conditions).
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Figure 6. Effect of growth temperature (°C) on the dye decolorization by tested fungi (50 mg/L dye, pH 9, 1% inoculum size, 7 days of incubation under shaking and dark conditions).
Figure 6. Effect of growth temperature (°C) on the dye decolorization by tested fungi (50 mg/L dye, pH 9, 1% inoculum size, 7 days of incubation under shaking and dark conditions).
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Figure 7. The effect of the inoculum size on the dye decolorization by the tested fungi (50 mg/L dye, 30 °C, pH 9, 7 days of incubation under shaking and dark conditions).
Figure 7. The effect of the inoculum size on the dye decolorization by the tested fungi (50 mg/L dye, 30 °C, pH 9, 7 days of incubation under shaking and dark conditions).
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Figure 8. The effect of aeration on the dye decolorization by the tested fungi (50 mg/L dye, 30 °C, pH 9, 1% inoculum size, 7 days of incubation under dark conditions).
Figure 8. The effect of aeration on the dye decolorization by the tested fungi (50 mg/L dye, 30 °C, pH 9, 1% inoculum size, 7 days of incubation under dark conditions).
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Figure 9. The effect of illumination on the dye decolorization by the tested fungi (50 mg/L dye, 30 °C, pH 9, 1% inoculum size, 7 days of incubation under shaking conditions).
Figure 9. The effect of illumination on the dye decolorization by the tested fungi (50 mg/L dye, 30 °C, pH 9, 1% inoculum size, 7 days of incubation under shaking conditions).
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Table 1. Dyes used and their CAS number, λmax, structure, molecular weight, and formula.
Table 1. Dyes used and their CAS number, λmax, structure, molecular weight, and formula.
Dye NameWavelength λmax (nm)Chemical Structure, Molecular Formula and Molecular Weight (g/mol)
Malachite green
(CAS No: 569-64-2)		620Sustainability 18 00921 i001
MF: C23H25ClN2; MW: 364.911
Reactive blue 19
(CAS NO: 2580-78-1)		595Sustainability 18 00921 i002
MF: C22H16N2Na2O11S3; MW: 626.51
Reactive black 5
(CAS NO:17095-24-8)		597Sustainability 18 00921 i003
MF: C26H21N5Na4O19S6; MW: 991.82
Table 2. Dyes decolorization efficiency of isolated fungi.
Table 2. Dyes decolorization efficiency of isolated fungi.
Isolate CodeScientific NameDye Decolorization (%) Mean ± SE of
MGRB19RB5
SRH1Aspergillus flavus var. columnaris-29.7 ± 2.4 cd45.3 ± 2.0 b
SRH2Aspergillus niger-33.7 ± 1.8 c-
SRH3Aspergillus niger-51.0 ± 1.7 b-
SRH4Aspergillus sulphureus---
SRH5Penicillium janthinellum--50.7 ± 3.4 b
SRH6Penicillium simplicissimum---
SRH7Penicillium citrinum---
SRH8Aspergillus parasiticus---
SRH9Aspergillus fumigatus30.7 ± 2.3 c58.0 ± 1.7 a58.7 ± 2.0 a
SRH10Absidia sp.---
SRH11Aspergillus terrus-50.0 ± 2.9 b32.3 ± 1.9 c
SRH12Rhizopus sp.10.0 ± 1.2 d44.3 ± 2.3 b-
SRH13Penicillum sp.40.3 ± 2.6 b--
SRH14Penicillium rubens55.3 ± 2.9 a25.3 ± 2.4 d-
The means followed by different letters (a, b, c, etc.) in each column are significantly different at p ≤ 0.05.
Table 3. Oxidoreductive enzyme activities in the extracellular and intracellular filtrates of the tested fungi after growth in medium without or with dyes.
Table 3. Oxidoreductive enzyme activities in the extracellular and intracellular filtrates of the tested fungi after growth in medium without or with dyes.
Tested EnzymesEnzyme Activity (U/mL) in Filtrates of
P. rubens After Growth in the
Medium		A. fumigatus After Growth in the Medium
Without MGwith MGWithout RB19with RB19Without
RB5		with RB5
Exo-laccase 9.39 ± 0.07 b1.98 ± 0.22 d17 ± 0.15 a1.26 ± 0.15 e17 ± 0.15 a8.09 ± 0.31 c
Endo-laccase 3.29 ± 0.28 c1.34 ± 0.05 d7.09 ± 0.08 b8.21 ± 0.08 a7.09 ± 0.08 b0.54 ± 0.04 e
Exo-LiP4.27 ± 0.09 e20.31 ± 0.20 a10.04 ± 0.11 d11.05 ± 0.13 c10.04 ± 0.11 d12.03 ± 0.16 b
Endo-LiP10.52 ± 0.40 a6.69 ± 0.16 d7.36 ± 0.11 d9.69 ± 0.06 b7.36 ± 0.11 d8.51 ± 0.3 c
Exo-MnP22.26 ± 1.40 b16.18 ± 0.11 c15.95 ± 0.21 c21.29 ± 0.40 b15.95 ± 0.21 c27.85 ± 0.17 a
Endo-MnP26.33 ± 1.30 d36.61 ± 0.38 b17.84 ± 0.54 e71.33 ± 0.75 a17.84 ± 0.54 e29.30 ± 0.34 c
Exo-tyrosinase25.25 ± 0.56 c46.08 ± 0.52 a3.26 ± 0.16 e30.84 ± 0.18 b3.26 ± 0.16 e16.03 ± 0.12 d
Endo-tyrosinase18.83 ± 0.85 d17.24 ± 0.18 d55.62 ± 0.38 a25.13 ± 0.11 c55.62 ± 0.38 a43.41 ± 0.92 b
Exo-MG reductase10.69 ± 0.23 c19.29 ± 0.40 b21.18 ± 0.34 a8.47 ± 0.34 d21.18 ± 0.34 a20.16 ± 0.46 ab
Endo-MG reductase17.39 ± 0.49 c24.42 ± 0.41 ab12.24 ± 2.18 d26.89 ± 0.52 a12.24 ± 2.18 d22.39 ± 0.55 b
Exo-RB19 reductase102.93 ± 1.10 b144.09 ± 0.61 a39.69 ± 0.29 d31.64 ± 0.41 e39.69 ± 0.29 d68.46 ± 0.61 c
Endo-RB19 reductase55.82 ± 0.82 b152.02 ± 1.15 a35.18 ± 0.25 c23.58 ± 0.72 d35.18 ± 0.25 c13.47 ± 0.28 e
Exo-RB5 reductase11.66 ± 0.58 b0.46 ± 0.06 d4.49 ± 0.24 c5.09 ± 0.54 c4.49 ± 0.24 c15.12 ± 0.74 a
Endo-RB5 reductase7.30 ± 0.03 d2.05 ± 0.28 e9.59 ± 0.49 c16.45 ± 0.35 a9.59 ± 0.49 c10.86 ± 0.29 b
Exo-NADH-DCIP reductase7.4 ± 0.23 a2.91 ± 0.20 b8.09 ± 0.06 a8.24 ± 0.60 a8.09 ± 0.06 a2.11 ± 0.12 b
Endo-NADH-DCIP reductase10.84 ± 0.29 a11.53 ± 0.40 a8.54 ± 0.28 b6.04 ± 0.07 c8.54 ± 0.28 b1.13 ± 0.11 d
Exo- means extracellular filtrate, and endo- means intracellular filtrate. Data were expressed as mean ± SE. The means followed by different letters (a, b, c, etc.) in each row are significantly different at p ≤ 0.05.
Table 4. Phytotoxicity test of dye solutions before and after decolorization by the tested fungi.
Table 4. Phytotoxicity test of dye solutions before and after decolorization by the tested fungi.
Parameter StudiedGermination (%)Shoot Length (cm)Root Length
(cm)		Relative Shoot Length
(%)		Relative Root Length
(%)		Relative Seed
Germination
(%)		Germination
Index
(%)
Water80 ± 2.89 ab2.5 ± 0.2 b1 ± 0.06 ab100100100100
MG (50mg/L)75 ± 1.73 bc1.5 ± 0.12 c0.8 ± 0.05 b60809448
Decolorized MG solution80 ± 1.73 ab2 ± 0.25 c1.2 ± 0.06 a8012010096
RB19 (100mg/L)70 ± 1.53 c0.6 ± 0.06 d0.3 ± 0.03 c24301067.2
Decolorized
RB19 solution		85 ± 1.53 a3.2 ± 0.21 a1.2 ± 0.26 a12812088153.6
RB5 (100mg/L)75 ± 2.08 bc0.8 ± 0.06 d0.2 ± 0.06 c3220946.4
Decolorized
RB5 solution		85 ± 2.08 a1.6 ± 0.15 c0.9 ± 0.08 ab649010657.60
Data were expressed as mean ± SE. The means followed by different letters (a, b, c, etc.) in each column are significantly different at p ≤ 0.05.
Table 5. COD and BOD of dye solutions before and after decolorization by the tested fungi.
Table 5. COD and BOD of dye solutions before and after decolorization by the tested fungi.
SampleCOD (mg O2/L)
Mean ± SE		BOD (mg O2/L)
Mean ± SE
MG dye (50 mg/L)36,055 ± 2514,330 ± 11
Decolorized MG by P. rubens19,583 ± 318975 ± 22
RB19 (100 mg/L)47,166 ± 919,675 ± 66
Decolorized RB19 by A. fumigatus17,250 ± 277931 ± 11
RB5 (100 mg/L) 35,611 ± 2513,502 ± 6
Decolorized RB5 by A. fumigatus17,944 ± 108093 ± 78
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El-Bendary, M.A.; Hamed, S.R.; Abdelhamid, S.A. Alkaline Mycoremediation: Penicillium rubens and Aspergillus fumigatus Efficiently Decolorize and Detoxify Key Textile Dye Classes. Sustainability 2026, 18, 921. https://doi.org/10.3390/su18020921

AMA Style

El-Bendary MA, Hamed SR, Abdelhamid SA. Alkaline Mycoremediation: Penicillium rubens and Aspergillus fumigatus Efficiently Decolorize and Detoxify Key Textile Dye Classes. Sustainability. 2026; 18(2):921. https://doi.org/10.3390/su18020921

Chicago/Turabian Style

El-Bendary, Magda A., Shimaa R. Hamed, and Sayeda Abdelrazek Abdelhamid. 2026. "Alkaline Mycoremediation: Penicillium rubens and Aspergillus fumigatus Efficiently Decolorize and Detoxify Key Textile Dye Classes" Sustainability 18, no. 2: 921. https://doi.org/10.3390/su18020921

APA Style

El-Bendary, M. A., Hamed, S. R., & Abdelhamid, S. A. (2026). Alkaline Mycoremediation: Penicillium rubens and Aspergillus fumigatus Efficiently Decolorize and Detoxify Key Textile Dye Classes. Sustainability, 18(2), 921. https://doi.org/10.3390/su18020921

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