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Phenol and its derivatives are widely distributed as environmental pollutants due to their presence in the effluents of many industrial processes like chemical, petrochemical, steel, pulp and paper mill industries[2]. These effluents frequently contain high concentrations of phenolics compounds that represents a serious ecological problem due to their widespread use, toxicity and occurrence throughout the environment. Many phenolic compounds are hazardous, toxic, endocrine disrupting, mutagenic, teratogenic, and/or carcinogenic[29]. Therefore, the removal of phenol and its derivatives from industrial wastewater is of great practical significance for environmental protection. Moreover, chlorophenols have been introduced into the environment through their use as biocides, for example penta chlorophenol (PCP), trichlorophenol (TCP) and tectrachloro phenol (TeCP) were used historically as fungicides in wood-preservative formulations[30, 31].
The biodegradation of phenols and chlorophenols by Penicillium species has been reported since the 90's and several works have continued studys in this regard (Table 1). In 1993, Hofrichter et al.[32] reported a Penicillium strain (Bi 7/2) able to grow on phenol (1,000 mg·l−1) as sole source of carbon and energy, and metabolized the phenol by the ortho-pathway. This strain also metabolizes 4-, 3- and 2-chlorophenol (50 mg·l−1) and 4-, 3- and 2-nitrophenol (50 mg·l−1), with phenol or glucose as co-substrate. The fact that an external carbon source, such as glucose, is needed implies an additional cost for the process. However, many Penicillium species can use phenol as a carbon source. This facilitates the development of a treatment process, since most of the effluents that contain chlorophenols, for example effluents from pulp and paper mill industries, contains phenol that can be utilized as a carbon source. Later, Marr et al.[33] found a Penicllium simplicissimum SK9117 strain able to degrade 3-chlorophenol, 4-chlorophenol, 4-bromophenol, 3-fluorophenol and 4-fluorophenol. However, monobromophenols and monochlorophenols were transformed to other intermediates (chlorohydroquinone, 4-chlorocatechol, 4-chloro-1,2,3-trihydroxybenzene, and 5-chloro-1,2,3-trihydroxybenzene) and could not support the fungus growth as the sole carbon and energy source, while monofluorophenols were mineralized completely without a co-substrate. In addition, difluorophenols were transformed by P. frequentans strain Bi 7/2, using phenol as a sole source of carbon and energy[35]. From the 90’s onwards, even up to 2021, more species of Penicillium were described with the ability to degrade phenol and chlorophenols (Table 1).
Table 1. Degradation of phenol and its derivatives by Penicillium spp.
Chemical compound External
carbon sourcePenicillium spp. Reference Phenol None P. frequentans Bi 7/2 [32] P. chrysogenum var. halophenolicum [23] P. chrysogenum ERK1 [8, 37] P. notatum [41] Resorcinol None P. chrysogenum var. halophenolicum [24, 36] Catechol,
HydroquinoneNone P. chrysogenum var. halophenolicum [36] 2-chlorophenol Phenol P. frequentans Bi 7/2 [32] Acetate P. camemberti [39] 3-chlorophenol Phenol P. frequentans Bi 7/2 [32] P. simplicissimum [33] 4-chlorophenol Phenol P. frequentans Bi 7/2 [32] P. simplicissimum [33] 2-nitrophenol Phenol P. frequentans Bi 7/2 [32] 3-nitrophenol Phenol P. frequentans Bi 7/2 [32] 4-nitrophenol Phenol P. frequentans Bi 7/2 [32] 4-bromophenol Phenol P. simplicissimum [33] 3-fluorophenol None P. simplicissimum [33] 4-fluorophenol None P. simplicissimum [33] 2,3- difluorophenol Phenol P. frequentans Bi 7/2 [35] 2,4- difluorophenol Phenol P. frequentans Bi 7/2 [35] 2,5- difluorophenol Phenol P. frequentans Bi 7/2 [35] 3,4- difluorophenol Phenol P. frequentans Bi 7/2 [35] 2,4,6-trichlorophenol Acetate P. chrysogenum ERK1 [7] Pentachlorophenol Acetate P. camemberti [39] 3,5-dimethyl-2,4-dichlorophenol None Penicillium spp [40] A case worth mentioning is that described by Leitão et al.[23], where a Penicillium chrysogenum var. halophenolicum was able to mineralize phenol completely at 5.8% NaCl, since this fungus was found to be halotolerant. This condition increases the chances to use this strain in biological treatments of phenol-containing wastewater, since some of them contain high concentrations of salts. The same strain degraded up to 250 mg·l−1 of resorcinol, as the sole carbon source in batch experiments in the presence of 58.5 g·l−1 of sodium chloride[24]. In addition, the authors showed the decrease of the acute toxicity of phenol and resorcinol, on Artemia franciscana larvae, after the bioremediation process with P. chrysogenum var. halophenolicum. Ferreira-Guedes & Leitão[36], described the removal efficiency of hydroquinone, catechol and resorcinol in binary substrate systems under saline conditions by the same P. chrysogenum var. halophenolicum strain. Catechol, resorcinol and hydroquinone are dihydroxybenzene isomers. The simultaneous presence of two or three isomers in a mixture will be defined as binary or ternary mixtures. The results of Ferreira-Guedes & Leitão[36] showed that the efficiency to remove dihydroxybenzene in binary substrate systems was higher than in mono substrate systems, except for hydroquinone. In the binary substrate systems, dihydroxybenzenes were removed not only simultaneously, but also preferentially. At high dihydroxybenzene concentration, fungal strain preferentially degraded hydroquinone followed by catechol and resorcinol.
Most of the results reported in Table 1, were obtained in batch culture in shaking conditions between 80 to 160 rpm. However, some studies showed that Penicillium frequentans Bi 7/2 and Penicillium chrysogeunm ERK1 could degrade dichlorophenols and phenol, respectively in resting mycelium conditions[35,37]. This may be convenient in terms of reducing the costs of wastewater treatment processes.
Furthermore, Aranciaga et al.[7] studied the biodegradation of 2,4,6-trichlorophenol, demonstrating that Penicillium chrysogenum ERK1 was able to degrade 85% of TCP in batch cultures in the presence of sodium acetate. In their study, hydroquinone and benzo quinone were identified as degradation intermediates, and although the complete mineralization of the TCP did not occur, a reduction on the phytotoxicity (50% approximately) was observed. The extent of degradation depends on the structure of the compound, the number of chlorine substituents, and the position of chlorine in the compound[38]. This directly influences the toxicity of the compound, which generally increases as the chlorinated substituents number increases. That is why it is equally important to reduce the toxicity of the effluent, even when the compound cannot be completely mineralized.
In the case of pentachlorophenol (PCP), Taseli & Gokcay[39] showed that Penicillium camemberti was able to remove 56% of PCP in batch experiments with acetate as a carbon source. In other experiments, without acetate but in the presence of Tween 80, P. camemberti removed 86% of the PCP. Moreover, an up-flow column reactor was operated with this fungus in the laboratory[39] and 77% of PCP removal was achieved in 4 d of contact without aeration and with minimum amount of carbon supplement. The percentages of PCP removal continued decreasing to 18.8% until the 18th day. These results agree with the results mentioned above, and show almost ideal conditions with respect to operating costs, without aeration and a reduced concentration of external carbon source.
In another study, Yan et al.[40] studied the performance of a Penicillium sp. strain to remove a 3,5-dimethyl-2,4-dichlorophenol (DCMX) from saline industrial wastewater. The results of batch experiments showed that biodegradation of DCMX was affected by pH value, salinity and DCMX concentration. The maximum DCMX removal efficiency was obtained at salinity 2.6%, temperature 32 °C and pH 5.87.
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The term colorant, which includes dyes and pigments, refers to substances capable of colouring a substrate. Colorants are used in industries like clothing, paints, plastics, photographs, prints and ceramics. They are used alone or in combination with other ingredients, which impart or alter the colour of the product[42]. Most dyes used in these processes are synthetic and are classified based on chromophore structures (namely acidic, basic, disperse, reactive, azo dyes and anthraquinone).
Dye wastewater treatment, mainly from textile industries, is really important in order to control its negative impact on the environment. Some dye precursors or its degradation byproducts were reported as toxic, carcinogenic and mutagenic[43,44], like aromatic amines which damage the DNA in cells and this leads to a risk of cancer[42].
The mycoremediation of dyes has shown to be a possible option to the conventional physico-chemical treatment technologies. The most widely used fungi in decolorization and degradation of dyes are the lignolytic fungi of class Basidiomycetes. However, non basidiomycotas fungi such as Aspergillus niger and A. terreus[45], Rhizopus oryzae[46] and some species of Penicillium[39,47−49] can also decolorize and/or biosorb diverse dyes[50,51].
For example, Shedbalkar et al.[47] showed that Penicillium ochrochloron decolorized cotton blue (50 mg·l−1), a triphenylmethane dye (Table 2). In this case, the dye was degraded to sulphonamide and triphenylmethane, as final products, by a battery of enzymes (lignin peroxidase, tyrosinase and aminopyrine N-demethylase) and the analysis of the phytotoxicity and microbial toxicity of extracted metabolites, suggested a decrease in their toxicity. The same P. ochrochloron has been shown to detoxify malachite green into p-benzyl-N,N-dimethylaniline and N,N-dimethyl-aniline hydrochloride. These metabolites were nontoxic when tested on Triticum aestivum and Ervum lens Linn (Table 2)[48]. The reaction was mediated by lignin peroxidase and the fungal culture was also found to have detoxified the textile effluent, reducing the values of total dissolved solids (TDS), total suspended solids (TSS), biochemical oxygen demand (BOD), and chemical oxygen demand (COD). In both works, it was demonstrated that P. ochrochloron was able to degrade and reduce the toxicity of two different dyes. However, it would be interesting to study the degradation and the analysis of the toxicity of the mixture of both dyes.
Table 2. Dye decolorization and degradation by Penicillium spp.
Penicillium spp Chemical group Dye name Concentration
(mg·l−1)Toxicity analysis Wastewater tested Reference P. chrysogenum Azo Direct Black 22,
Direct Yellow 86,
Direct Blue 200200 T. aestivum Diluted effluent [4, 6] P. ochrochloron Triphenylmethane Cotton blue 50 T. aestivum
E. lens
A. vinelandiiNo [47] Malachite green 50 T. aestivum
E. lensDiluted effluent [48] P. simplicissimum
AzoReactive Red 198 Reactive Blue 214 200 D. pulex No [52] Phthalocyanine Reactive Blue 21 200 D. pulex No [52] Triphenylmethane Methyl Violet, Crystal Violet, Malachite Green
Cotton Blue50−100 V. radiate
B. cereus
S. aureusNo [53, 54] P. oxalicum Azo Acid Red 183, Direct Blue 15 Direct Red 75 100−300 No No [5] P. pinophilum Triphenylmethane Malachite Green 10 No No [55] Moreover, Penicillium simplicissimum INCQS 40211 decolorized the textile dyes: Reactive Red 198 (RR198), Reactive Blue 214 (RB214), Reactive Blue 21 (RB21) and their mixture[52]. In this case, it was suggested that dye decolorization involved dye adsorption by the biomass first, followed by degradation. In addition, P. simplicissimum reduced the toxicity of RB21 from moderately acutely toxic to minor acutely toxic and it also reduced the toxicity of RB214 and the mixture of the three dyes, which remained minor acutely toxic. It is also worth noticing that the fungus increased the toxicity of RR198. These results showed that more studies regarding dye degradation and toxicity reduction by P. simplicissimum INCQS 40211 are necessary. Later, Chen & Ting[53] and Chen et al.[54] described the biosorption and biodegradation activities of the same Penicillium species towards triphenylmethane dyes. Crystal Violet (CV), Methyl Violet (MV), Malachite Green (MG), and Cotton Blue (CB) were decolorized by P. simplicissimum with 98.7%, 97.5%, 97.1%, and 96.1 % of decolorization efficiency, respectively, within 2 h of incubation (50 mg·l−1, pH 5.0, 25 ± 2 °C) (Table 2). In this work, only UV–visible spectral analysis of dyes was conducted before and after treatment with P. simplicissimum, indicating the occurrence of biodegradation, however the intermediate products of the degradation or complete mineralization could not be confirmed. Some enzymatic activities were detected as manganese peroxidase, tyrosinase, triphenylmethane reductase activities, suggesting their involvement in the degradation pathway. In addition, reduction of phytotoxicity and microbial toxicity were observed only for MG.
Other Penicillium species that have been reported to have decolorization/degradation abilities are: Penicillium oxalicum[5], Penicillium pinophilum[55], Penicillium purpurogenum[56] and a Penicillium strain not characterized at the species level[57].
In all the cases mentioned above, degradation occurs with the addition of some external carbon source. In general, dyes are evaluated in culture media and only in a few cases mixtures of dyes and real effluents are studied.
Another strain, which is worth mentioning, is Penicillium chrysogenum. This fungus showed great potential to decolorize and degrade three azo dyes (at 200 mg·l−1) independently or a mixture of them, even in a complex wastewater matrix as it was real textile wastewater[6] (Table 2). The degradation process was carried out in the presence of glucose as a carbon source and showed that decolorization rates differed depending on the azo dye structure (number of azo bonds, terminal or substituent groups, steric hindrance, etc.). Moreover, a kinetic model for degradation was developed, which allowed prediction of the degradation kinetics of the mixture of the three azo dyes and the real textile wastewater[6]. Later, the immobilization on loofah of the same strain of P. chrysogenum significantly increased the degradation rate of DB22 in a laboratory scale as well as at bench scale reactor, with respect to the non-immobilized treatment[4]. The degradation rate of immobilized cells increased twice as compared to free-cells control and at day 5 the decolorization was almost complete, while without loofah, the total decolorization took more than 10 d. The results of these studies show an improvement in the azo dye degradation process, however, using glucose as a carbon source is still costly. Therefore, more studies should be carried out using alternative carbon sources such as waste from food industries, for example starch, beer bagasse, etc. to minimize effluent treatment costs.
Erdal & Taskin[58], also showed the potential of a strain of P. chrysogenum MT-6 to decolorize the textile dye Reactive Black-5. However, degradation was not confirmed in this case.
Lately, Fouda et al.[59] biosynthesized maghemite nanoparticles (γ-Fe2O3-NPs) using Penicillium expansum with the purpose of treating wastewater. Decolorization and degradation analyses, indicated that γ-Fe2O3-NPs was an effective biocatalyst for dye degradation under dose- and time-dependent manner. The highest decolorization (89%–90%) occurred after 6.0–8.0 h of incubation. The contaminant load of the textile wastewater was improved, as indicated by the reduction in COD, TDS, and TSS. Although, GC-MS results showed the complete disappearance of peaks in treated textile wastewater in comparison with the untreated samples, no toxicity analysis was carried out.
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Polycyclic aromatic hydrocarbons (PAHs) are poorly soluble, hydrophobic organic compounds which are among the most widely distributed organic contaminants[2]. They are released/transposed due to incomplete combustion of organic matter in petrochemical industries and proven to be highly genotoxic, mutagenic, carcinogenic as well as teratogenic to humans[64]. The PAHs are considered important environmental pollutants since they are the most frequently found in soil pollutants[65].
As described by Leitão[2] and Rabha & Jha[14], there are several reports regarding biodegradation of PAHs by Penicillium species[34, 66−72] (Table 3). The effect of oxygen, ciclodextrins, surfactants, carbon and nitrogen sources, and other factors on PAHs biodegradation were studied in these reports. In addition, the presence of pyrene for example was described to influence the size and shape of the fungal pellets as well as the density of mycelium and hyphal length[71]. These studies, showed the degradation of different PAHs separately. In 2014, Vanishree et al.[73] isolated a Penicillium sp. strain from petrol bunks soils and automobile workshops which can tolerate, grow and degrade different petrol concentrations.
Table 3. Hydrocarbon degradation by Penicillium spp.
Chemical compound Penicillium spp Reference Acenaphthene Penicillium sp. CHY-2 [74] Anthracene P. oxalicum [75] P. ilerdanum [76] P. oxalicum SYJ-1 [77] Benzo[a]pyrene Penicillium sp. CHY-2 [74] P. janthinellum [66, 67] Benz[a]antracene P. janthinellum [67] Butylbenzene Penicillium sp. CHY-2 [74] Chrysene P. janthinellum [67] Ethylbenzene Penicillium sp. CHY-2 [74] Dibenz[a,h]anthracene P. janthinellum [67] Dibenzothiophene P. oxalicum [75] Dibenzofuran P. oxalicum [75] Fluorene P. italicum [69] P chrysogenum [68] Fluoranthene P. ilerdanum [76] Naphthalene P. ilerdanum [76] Penicillium sp. CHY-2 [74] Phenanthrene P. frequentans [72] P. ilerdanum [76] P. oxalicum [75] P. oxalicum SYJ-1 [77] Pyrene P. simplicissimum,
P. funiculosum,
P. harzianum,
P. terrestre[70] P. janthinellum, [66,67,70] P. ochrochloron [71] P. glabrum [34] P. ilerdanum [76] Penicillium oxalicum SYJ-1 [77] Petrol Penicillium sp [73] Decane Penicillium sp. CHY-2 [74] Dodecane Penicillium sp. CHY-2 [74] Octane Penicillium sp. CHY-2 [74] Penicillium oxalicum was also reported to be able to completely remove anthracene and dibenzothiophene within 4 d, as well as phenanthrene and dibenzofuran, although at slower rates[75]. Most Penicillium strains which degrade PAHs carried out the degradation through the cytochrome P450 monooxygenase enzyme pathway. However, cytochrome P450 monooxygenase plays a role in the first steps of transformation of PAHs, while induction of oxygenase activity was detected in the subcellular fraction of the fungal mycelium exposed to these aromatic compounds.
Aranda et al.[75] demonstrated that glucose was required for anthracene degradation by P. oxalicum using a defined growth medium with low carbon content for stable isotope tracer experiments with 13C 6-anthracene. Therefore, anthracene mineralization could not be confirmed, but 13C-labelled oxy and hydroxy-derivatives were identified by nuclear magnetic resonance (NMR) as major metabolites. Although P. oxalicum was found to be the fungus with the highest and fastest PAHs degradation capability, the toxicity of these major metabolites should be evaluated, for a safe application in biotechnological pollutant removal processes.
Antarctic soil has also been a source of hydrocarbon degrading microorganisms[78,79] including Penicillium. A Penicillium sp. CHY-2 isolated from Antarctic soil was able to degrade not only aromatic hydrocarbons but also aliphatic hydrocarbons[74]. The highest level of degradation was for decane (49.0%), followed by butylbenzene (42.0%) and dodecane (33.0%), and lower levels of degradation were found for naphthalene (15.0%), acenaphthene (10.0%), octane (8.0%), ethylbenzene (4.0%), and benzo[a]pyrene (2.0%) at 20 °C. Later, the authors studied decane degradation in depth and showed that the addition of carbon sources such as glucose (5 g·l–1) and Tween-80 (5 g·l–1) enhanced decane degradation by about 1.8-fold and 1.61-fold respectively at 20 °C. 1,6-hexanediol was identified as one of the metabolites produced during the degradation of decane and a manganese peroxidase (MnP) enzyme was isolated from the fungi.
Over the years, more and more studies with new isolates able to degrade hydrocarbons have appeared, for example in 2021 a Penicillium ilerdanum NPDF1239-K3-F21, isolated from Arabian sea sediments, showed > 75% ability to degrade naphthalene, phenanthrene, pyrene, fluoranthene and anthracene[76]. However, beyond the degradation processes, further optimization, pilot scale and toxicity studies must be carried out before applying these processes to wastewater or bioremediation treatments.
Recently, Zhou et al.[77] showed a novel self-assembled PAH-degrading fungal mycelium Penicillium oxalicum SYJ-1-carbon nanotube (CNT) composites for pyrene removal. Their study is a good example of the combination of biodegradation and nanotechnology to increase the total PAH removal efficiency. Anthracene, phenanthrene and pyrene could be removed by 65%–92% within 72 h, while no naphthalene removal was observed by Penicillium oxalicum SYJ-1. Due to pyrene moderate degradation, this was selected as a model substrate to evaluate the possible positive effect of CNTs. The addition of it did not affect the growth of strain SYJ-1 and the complete removal of pyrene (20 mg·l–1) was achieved within 48 h, while the sole fungus and CNTs alone could only remove 72% and 80% of pyrene at 72 h, respectively. Besides, the authors carried out a transcriptomic analysis, and a cytochrome P450 inhibition experiment and identified some degradation products, which allowed them to suggest that an intracellular PAH transformation pathway was employed by strain SYJ-1.
Further, the versatility of the assembly approach was also confirmed by adding different nanomaterials (TiO2, δ-MnO2 and α-MnO2) and using them to remove phenanthrene, which was successful.
Most of the studies carried out on hydrocarbon degradation by Penicillium spp. showed that pilot scale and toxicity studies on the metabolites are scarce, being an important point for the design of a suitable wastewater treatment.
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So far we have reviewed large groups of organic pollutants, of which there are many references as we can see above, dyes, phenols, hydrocarbons, and others. Penicillium species have demonstrated their ability to degrade other xenobiotic compounds (Table 4).
Table 4. Degradation of other organic pollutants by Penicillium spp.
Compound Penicillium spp Reference Formaldehyde P. chrysogenum DY-F2 [86] Diethylketone Penicillium spp. [87] Polychlorinated biphenyls P. chrysogenum,
P. citreosulfuratum,
P. canescens.[88] Sodium dodecylbenzene sulfonate P. chrysogenum [11] Poly ɛ-caprolactone and Polyester vylon 200 P. fellutanum (Lipases) [89, 90] In 2014, Luo et al.[86] reported a formaldehyde-degrading Penicillium chrysogenum DY-F2 strain, which was isolated from deep sea sediment. This characteristic is interesting, as this makes this fungus useful to be used for the bioremediation of polluted marine environment or wastewater with high salt content. In most studies reported previously, the fungi were isolated from contaminated soils, river sediments or from wastewater treatment plants. P. chrysogenum DY-F2 showed high formaldehyde resistance and was able to grow in the presence of formaldehyde up to 3,000 mg·l–1. In addition, it was able to degrade formaldehyde as the sole source of carbon and energy with the formation of formic acid as the intermediate. This study by Luo et al.[86] was the first to report degradation of formaldehyde by marine fungi.
Some Penicillium species, like P. citreonigrum, P. oxalicum, P. chrysogenum, P. spinulosum, P. verruculosum and P. variabile can efficiently degrade diethyl ketone[87], sodium dodecyl benzene sulfonate[11] and grow well in agar media containing paraffin, chitin, cellulose, leather, pectin, skim milk, sunflower oil, and starch[9] (Table 4). However, the disappearance of the substrates was not measured, and therefore it cannot be confirmed that there was degradation or mineralization of these compounds.
Polychlorinated biphenyls (PCBs) were widely used in electrical equipment and in heat transfer fluids. These pollutants are widespread, persistent, deleterious to the environment and very dangerous for humans. Germain et al.[88] recently described the isolation of four native fungal strains with a remarkable biodegradation capacity, greater than 70%. Three of the four isolates belong to the genus Penicillium: P. chrysogenum, P. citreosulfuratum and P. canescens. The last one was the only one that reduced the toxicity related to PCBs and their metabolites, significantly.
Lately, Amin et al.[89, 90] described the degradation of poly ɛ-caprolactone (PCL), a biodegradable aliphatic polyester, and of polyester vylon 200 (PV-200), a synthetic non-biodegradable plastic, by lipases from Penicillium fellutanum. These lipases exhibited stability over a broad pH spectrum and by incubation with various industrially relevant organic solvents (benzene, hexanol, ether, and acetone). Under optimal operating conditions, lipase catalyzed the degradation of PCL film leading to 66% weight loss and 81% weight loss for PV-200. These results showed that P. fellutanum lipase would be a prospective green and ecofriendly biocatalytic system for efficient degradation and depolymerization of polyester for environmental safety.
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The author would like to thank National Scientific and Technical Research Council (CONICET) and National University of Mar del Plata for supporting this work. Thank you very much to Inés Lanfranconi and Jorge Froilán González for the critical reading of the manuscript and her helpful suggestions.
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About this article
Cite this article
Wolski EA. 2023. The versatility of Penicillium species to degrade organic pollutants and its use for wastewater treatment. Studies in Fungi 8:2 doi: 10.48130/SIF-2023-0002
The versatility of Penicillium species to degrade organic pollutants and its use for wastewater treatment
- Received: 28 November 2022
- Accepted: 27 December 2022
- Published online: 31 January 2023
Abstract: The removal of xenobiotics from industrial wastewater is of great interest to avoid environmental contamination. Penicillium species have been shown to be able to adapt its metabolism to many different circumstances and these fungi can use different xenobiotics as a carbon source. In this review, the ability of Penicillium to degrade different xenobiotic compounds is discussed. This review describes not only the biodegradation processes but also addresses the toxicity of the degradation products as well as the potential application of these processes in wastewater treatment. Penicillium strains have proven to be versatile and capable of being used for the biodegradation of different organic pollutants (phenols, azo dyes, hydrocarbons, pharmaceutical compounds, etc.) and show high potential to be used for wastewater treatment. From this review, it is concluded that beyond the degradation and optimization processes; pilot scale studies and toxicity must be carried out.
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Key words:
- Biodegradation /
- Fungi /
- Toxicity /
- Xenobiotic compounds.