Benzoate or 4-hydroxybenzoate is initially released by the organism as energetically more difficult to degrade [7], [8], but completely degraded lately.
Due to very stable and xenobiotic nature, reactive dyes are difficult to degrade or exhibit slow degradation [5].
Since, lignin is difficult to degrade, the percentage of un-degraded acid insoluble lignin was found to be 28.67, 35.67, 46.67, 28.33, and 36.33 % in trials 1, 2, 3, 4, and 5, respectively, during the composting process.
In this study, three independent parallel laboratory-scale TBABs were run simultaneously to degrade n-hexane, a hydrophobic VOC known to be difficult to degrade.
Although it is difficult to degrade β-methyl-branched alkanes via the β-oxidation pathway, multiple Pseudomonas strains can degrade short chain alkanes via the citronellol pathway.
In favour of this, it has been shown that polyglutamine proteins are intrinsically difficult to degrade [14], [15] and it has been reported that eukaryotic proteasomes are unable to degrade within polyglutamine tracts [17].
However, plant cell wall structure is extremely difficult to degrade and acts as a natural protective barrier.
These compounds are often stable and difficult to degrade in wastewater facilities, thus posing a serious long-time risk.
Bioaccumulation, another way in which pollution can harm the environment, is the internal accumulation of a pollutant that is very difficult to degrade or expel from the body, such as mercury.
However, there are limitations in the use of vegetable tanning materials because of its high organic load in the effluent, which are difficult to degrade leading to high chemical oxygen demand (COD).
