# Mycoremediation as a Potentially Promising Technology: Current Status and Prospects--A Review
## 9 Emerging Mycoremediation Applications
### Polycyclic Aromatic Hydrocarbon (PAHs) by Myoremediation  
The term \"PAHs,\" also known as \"polyarenes,\" refers to a large and diverse group of substances (more than 100 substances) that contain over two condensed benzene groups in a linear form or an angular cluster. Aromatic rings categorize PAHs; small PAHs have fewer than six rings, whereas large PAHs have more. PAHs' melting and boiling points rise along with their molecular weight while water solubility and vapour pressure decrease. The impacts of bioaccumulation and persistence on human health and the environment are severe. The accumulation of PAHs in adipose tissue, kidneys, and liver leads to the formation of even more dangerous compounds such as formaldehyde, benzene, and heterocyclic aromatic amines. These substances present a more significant risk because of their widespread environmental presence, biodegradation resistance, and bioaccumulation capacity [267]. The risk persists due to the mutagenic and carcinogenic results of breathing in air containing PAHs. Mycoremediation is, therefore, a more effective method, and this procedure has a reasonable cost-to-benefit ratio compared to other methods. Fungi can degrade PAHs due to their intrinsic properties. For example, ligninolytic fungal enzymes are known to be nonspecific to their substrates, prompting researchers to explore this technique [268]. Figure 5: Schematic representation of the emerging applications of mycoremediation. Various tests, such as dye decolouration, guaiacol, and gallic acid, evaluate the ligninolytic properties. Several other pollutants can also be broken down by enzymes that degrade lignin. These enzymes are located outside cells, are abundant in fungi, and are extracellular. These enzymes are ideal for bioremediation because they are not substrate-specific [269]. These fungi are believed to oxidize PAHs initially using their peroxididases in the extracellular environment. Some PAHs are immediately oxidized by fungal lignin peroxididases, while fungal manganese peroxididases indirectly oxidize others via enzyme-mediated lignin peroxidation [270]. Hydrocarbons derived from petroleum are so pervasive that we cannot avoid them. However, they are the world's most significant pollutants. Fungi are among the many microorganisms that have demonstrated the capacity to degrade petroleum hydrocarbon effluents. Generally, fungi are more effective than bacteria at degrading petroleum effluents. The fungus consumes petroleum as a source of carbon and removes it from the environment if it grows near an oil well. _Penicillium sp., Rhizopus sp., Aspergillus niger_, and _Aspergillus terrus_ are the fungi species that have been tested for bioremediation of hydrocarbons. _Cochlioblous lutanus_ is the newest member of this group of fungi that degrade the oil. As previously stated, _Penicillium_ sp. possesses the lowest elimination potential, and _Aspergillus niger_ possesses the highest bioremediation potential among the species. There are four major groups of fungi, and Deuteromycetes and Ascomycetes both have a large number of members that contribute to the bioremediation of hydrocarbons. Numerous microorganisms in diesel oil sludge tanks degrade petroleum hydrocarbons and aliphatic hydrocarbons. _Aspergillus fumigatus_ was more effective than other tested microorganisms [271]. Propionic acid and other metabolites were detected in the water phase of _A. fumigatus_ growth assays after 60 days of incubation. As a beneficial species for mycoremediation, _Pleurots ostreatus_ possesses anti-oxidant, anti-cancer, immunostimulatory, anti-inflammatory, and anti-diabetic therapeutic properties [272]. Numerous studies have demonstrated that it is effective at degrading petroleum hydrocarbons. The fungus _Pleurots ostreatus_ retains many enzymes that degrade multiple compounds. _P ostreatus_ can transmit water, nutrients, bacteria, and contaminants along the mycelium, dispersing resources for contaminant degradation within the soil matrix. _P.