# Microbial Bioremediation and Biodegradation of Petroleum Products--A Mini Review
## 4 Emerging Biodegradation Technologies  
Petroleum hydrocarbons have adverse effects on plants and animals. They contaminate the environment and challenge academic and industrial experts to find mutually agreed remediation options to avert the impact on petroleum-contaminated media. It is worth noting that about 60-90% of the chemical composition of petroleum is biodegradable, which is why research efforts are directed toward new degradation technologies, in particular, the bioremediation of petroleum hydrocarbons in soil and water [35]. Some of these remediation technologies are shown in Figure 5. The subsequent rapid and complete degradation occurs under aerobic conditions for most organic pollutants [52]. The first intracellular organic pollutant attack occurs due to oxidation and activation, and oxygen implementation is the critical factor in enzymatic motivation by peroxides and oxygenates [53]. Peripheral degradation pathways convert organic pollutants into intermediate stages of the central intermediate metabolism, such as the tricarboxylic acid cycle. Cell biomass metabolism is produced by metabolites of major precursors such as acetyl-CoA, pyruvate, and succinate [46]. The saccharides required for various biosynthesis and growth are synthesized by gluconeogenesis. The pH reduction may be possible through a specific enzyme system. Other processes are also involved, such as microbial cell adhesion to substrates and the development of biosurfactants [54]. pH values can be preferentially metabolized by a single strain of microorganism or by a microbial strain synthesis relevant to the same or different genera. The consortium has shown that there are more ways than individual cultures to metabolize or degrade PHs.  
\begin{table}
\begin{tabular}{c c} \hline
**Parameter** & **Condition** \\ \hline \multirow{4}{*}{Nutrients} & Additional nutrients enhance the biodegradation of oil pollution. \\  & Numerous articles have been published on the detrimental effects of \\  & excessive NPK use in the degradation process of hydrocarbons. \\  & It has been discovered that organic fertilisers, such as chicken manure, \\  & speed up the biodegradation of contaminated soil. \\  & Photo-oxidation increased the degradation rate of oil hydrocarbons by \\  & improving their bioavailability and, as a result, their microbial actions. \\  & The presence of usable substrates, the soil type and the rate of O\({}_{2}\) \\  & utilisation by microbes that can deplete oxygen all influence oxygen levels. \\  & During the biodegradation of crude oil in soil, oxygen concentration is \\  & thought to be a rate limiting parameter. \\  & In the early stages of aromatic, cyclic, and aliphatic hydrocarbon \\  & catabolism by fungi and bacteria, oxygenases oxidase the compound, which \\  & requires O\({}_{2}\). \\  & Excellent hydrocarbon bioremediation has been observed in temperate \\  & regions with psychrophilic surroundings. \\  & The maximum rate of degradation occurs at temperatures ranging from \\  & 15 \({}^{\circ}\)C to 20 \({}^{\circ}\)C in marine, 20 \({}^{\circ}\)C to 30 \({}^{\circ}\)C in freshwater, and 30 \({}^{\circ}\)C to 40 \({}^{\circ}\)C in soil. \\  & Enzymatic activity declines at lower temperatures, which also slows the \\  & rate of biodegradation. \\  & Low temperatures increase oil viscosity and decrease the volatility of \\  & harmful low molecular weight hydrocarbons, reducing microbial \\  & degradation. \\  & The vulnerability of hydrocarbons to microbial attack is proportional to the \\  & degree of degradability. Saturates-light aromatics-high molecular weight \\  & aromatic polar compounds or n-alkanes-branched alkanes-cyclic alkanes \\  & Photo oxidation, evaporation \\  & Microorganisms \\ \hline \end{tabular}
\end{table}
Table 3: Cont.