Sustainable Biosynthesis of Esterase Enzymes of Desired Characteristics of Catalysis for Pharmaceutical and Food Industry Employing Specific Strains of Microorganisms

Abridgement of Microbial Esterases and Their Eminent Industrial Endeavors

Esterases are hydrolases that contribute to the hydrolysis of ester bonds into both water-soluble acyl esters and emulsified glycerol-esters containing short-chain acyl groups. They have garnered significant attention from biotechnologists and organic chemists due to their immense commercial value. Esterases, with their diverse and significant properties, have become highly sought after for various industrial applications. Synthesized ubiquitously by a wide range of living organisms, including animals, plants, and microorganisms, these enzymes have found microbial esterases to be the preferred choice in industrial settings. The cost-effective production of microbial esterases ensures higher yields, unaffected by seasonal variations. Their applications span diverse sectors, such as food manufacturing, leather tanneries, paper and pulp production, textiles, detergents, cosmetics, pharmaceuticals, biodiesel synthesis, bioremediation, and waste treatment. As the global trend shifts toward eco-friendly and sustainable practices, industrial processes are evolving with reduced waste generation, lower energy consumption, and the utilization of biocatalysts derived from renewable and unconventional raw materials. This review explores the background, structural characteristics, thermostability, and multifaceted roles of bacterial esterases in crucial industries, aiming to optimize and analyze their properties for continued successful utilization in diverse industrial processes. Additionally, recent advancements in esterase research are overviewed, showcasing novel techniques, innovations, and promising areas for further exploration.

Mitochondrial Esterase Activity Measured at the Single Organelle Level by Nano-flow Cytometry

Monitoring mitochondrial esterase activity is crucial not only for investigating mitochondrial metabolism but also for assessing the effectiveness of mitochondrial-targeting prodrugs. However, accurately detecting esterase activity within mitochondria poses challenges due to its ubiquitous presence in cells and the uncontrolled localization of fluorogenic probes. To overcome this hurdle and reveal variations among different mitochondria, we isolated mitochondria and preserved their activity and functionality in a buffered environment. Subsequently, we utilized a laboratory-built nano-flow cytometer in conjunction with an esterase-responsive calcein-AM fluorescent probe to measure the esterase activity of individual mitochondria. This approach enabled us to investigate the influence of temperature, pH, metal ions, and various compounds on the mitochondrial esterase activity without any interference from other cellular constituents. Interestingly, we observed a decline in the mitochondrial esterase activity following the administration of mitochondrial respiratory chain inhibitors. Furthermore, we found that mitochondrial esterase activity was notably higher in the presence of a high concentration of ATP compared to that of ADP and AMP. Additionally, we noticed a correlation between elevated levels of complex IV and increased mitochondrial esterase activity. These findings suggest a functional connection between the mitochondrial respiratory chain and mitochondrial esterase activity. Moreover, we detected an upsurge in mitochondrial esterase activity during the early stages of apoptosis, while cellular esterase activity decreased. This highlights the significance of analyzing enzyme activity within specific organelle subregions. In summary, the integration of a nano-flow cytometer and fluorescent dyes introduces a novel method for quantifying mitochondrial enzyme activity with the potential to uncover the alterations and unique functions of other mitochondrial enzymes.

Nutraceutical Combinational Therapy for Diarrhoea Control with Probiotic Beverages from Fermented Fruits, Vegetables and Cereals to Regain Lost Hydration, Nutrition and Gut Microbiota

This article deals with the condition of irregular bowel movements known as diarrhoea, its pathology, symptoms and aetiology. The information has been presented on causes of diarrhoea that include gut infections, food intolerances and allergies to certain ingredients, problems in the gastrointestinal tract like irritable bowel syndrome, inflammatory bowel disease and, the condition of dysbiosis which occurs due to long-term use of antibiotics, or other medicines, etc. Most cases of diarrhoea can be resolved without needing medical treatment; however, it is still important to avoid dehydration of the body and use some supplements to get necessary nutrients which are lost with frequent bowel movements before they can get absorbed and assimilated in the gastrointestinal tract. Probiotic products are reported as natural therapeutic agents, which can reduce the risk of diarrhoea in both adults and children. The intake of dietary fluid supplements in the form of fermented beverages containing probiotic strains could help in diarrhoea control. The patient would achieve benefits with the consumption of these functional beverages in three ways-by regaining lost fluids to the body, supplementing beneficial gut bacteria to restore diversity in gut microbiota, which was disturbed in the condition of diarrhoea as well as regaining a source of quick nutrition to recoup energy.

Immobilization of Hyperthermostable Carboxylesterase EstD9 from Anoxybacillus geothermalis D9 onto Polymer Material and Its Physicochemical Properties

Carboxylesterase has much to offer in the context of environmentally friendly and sustainable alternatives. However, due to the unstable properties of the enzyme in its free state, its application is severely limited. The present study aimed to immobilize hyperthermostable carboxylesterase from Anoxybacillus geothermalis D9 with improved stability and reusability. In this study, Seplite LX120 was chosen as the matrix for immobilizing EstD9 by adsorption. Fourier-transform infrared (FT-IR) spectroscopy verified the binding of EstD9 to the support. According to SEM imaging, the support surface was densely covered with the enzyme, indicating successful enzyme immobilization. BET analysis of the adsorption isotherm revealed reduction of the total surface area and pore volume of the Seplite LX120 after immobilization. The immobilized EstD9 showed broad thermal stability (10-100 °C) and pH tolerance (pH 6-9), with optimal temperature and pH of 80 °C and pH 7, respectively. Additionally, the immobilized EstD9 demonstrated improved stability towards a variety of 25% (v/v) organic solvents, with acetonitrile exhibiting the highest relative activity (281.04%). The bound enzyme exhibited better storage stability than the free enzyme, with more than 70% of residual activity being maintained over 11 weeks. Through immobilization, EstD9 can be reused for up to seven cycles. This study demonstrates the improvement of the operational stability and properties of the immobilized enzyme for better practical applications.

Biodegradation of Selected Hydrocarbons by Fusarium Species Isolated from Contaminated Soil Samples in Riyadh, Saudi Arabia

BACKGROUND

Microbial biodegradation of oil-hydrocarbons is one of the sustainable and cost-effective methods to remove petroleum spills from contaminated environments. The current study aimed to investigate the biodegradation abilities of three Fusarium isolates from oil reservoirs in Saudi Arabia. The novelty of the current work is that the biodegradation ability of these isolates was never tested against some natural hydrocarbons of variable compositions, such as Crude oil, and those of known components such as kerosene and diesel oils.

METHODS

The isolates were treated with five selected hydrocarbons. The hydrocarbon tolerance test in solid and liquid media was performed. The scanning electron microscope (SEM) investigated the morphological changes of treated fungi. 2, 6-Dichlorophenol Indophenol (DCPIP), drop collapse, emulsification activity, and oil Spreading assays investigated the biodegradation ability. The amount of produced biosurfactants was measured, and their safety profile was estimated by the germination assay of tomato seeds.

RESULTS

The tolerance test showed enhanced fungal growth of all isolates, whereas the highest dose inhibition response (DIR) was 77% for Fusarium proliferatum treated with the used oil (p < 0.05). SEM showed morphological changes in all isolates. DCPIP results showed that used oil had the highest biodegradation by Fusarium verticillioides and Fusarium oxysporum. Mixed oil induced the highest effect in oil spreading, drop collapse, and emulsification assay caused by F. proliferatum. The highest recovery of biosurfactants was obtained by the solvent extraction method for F. verticillioides (4.6 g/L), F. proliferatum (4.22 g/L), and F. oxysporum (3.73 g/L). The biosurfactants produced by the three isolates stimulated tomato seeds' germination more than in control experiments.

CONCLUSION

The current study suggested the possible oil-biodegradation activities induced by three Fusarium isolates from Riyadh, Saudi Arabia. The produced biosurfactants are not toxic against tomato seed germination, emphasizing their environmental sustainability. Further studies are required to investigate the mechanism of biodegradation activities and the chemical composition of the biosurfactants produced by these species.