Alkaline lipase production by novel meso-tolerant psychrophilic Exiguobacterium sp. strain (AMBL-20) isolated from glacier of northeastern Pakistan

Recent insight into the advances and prospects of microbial lipases and their potential applications in industry

Enzymes play a crucial role in various industrial sectors. These biocatalysts not only ensure sustainability and safety but also enhance process efficiency through their unique specificity. Lipases possess versatility as biocatalysts and find utilization in diverse bioconversion reactions. Presently, microbial lipases are gaining significant focus owing to the rapid progress in enzyme technology and their widespread implementation in multiple industrial procedures. This updated review presents new knowledge about various origins of microbial lipases, such as fungi, bacteria, and yeast. It highlights both the traditional and modern purification methods, including precipitation and chromatographic separation, the immunopurification technique, the reversed micellar system, the aqueous two-phase system (ATPS), and aqueous two-phase flotation (ATPF), moreover, delves into the diverse applications of microbial lipases across several industries, such as food, vitamin esters, textile, detergent, biodiesel, and bioremediation. Furthermore, the present research unveils the obstacles encountered in employing lipase, the patterns observed in lipase engineering, and the application of CRISPR/Cas genome editing technology for altering the genes responsible for lipase production. Additionally, the immobilization of microorganisms' lipases onto various carriers also contributes to enhancing the effectiveness and efficiencies of lipases in terms of their catalytic activities. This is achieved by boosting their resilience to heat and ionic conditions (such as inorganic solvents, high-level pH, and temperature). The process also facilitates the ease of recycling them and enables a more concentrated deposition of the enzyme onto the supporting material. Consequently, these characteristics have demonstrated their suitability for application as biocatalysts in diverse industries.

Enhancement effect of AgO nanoparticles on fermentative cellulase activity from thermophilic Bacillus subtilis Ag-PQ

BACKGROUND

Cellulase is an important bioprocessing enzyme used in various industries. This study was conducted with the aim of improving the biodegradation activity of cellulase obtained from the Bacillus subtilis AG-PQ strain. For this purpose, AgO and FeO NPs were fabricated using AgNO3 and FeSO4·7H2O salt respectively through a hydro-thermal method based on five major steps; selection of research-grade materials, optimization of temperature, pH, centrifuge, sample washed with distilled water, dry completely in the oven at the optimized temperature and finally ground for characterization. The synthesized NPs were characterized by scanning electron microscope (SEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD) to confirm the morphology, elemental composition, and structure of the sample respectively. The diameter of the NPs was recorded through SEM which lay in the range of 70-95 nm.

RESULTS

Cultural parameters were optimized to achieve better cellulase production, where incubation time of 56 h, inoculum size of 5%, 1% coconut cake, 0.43% ammonium nitrate, pH 8, and 37 °C temperature were found optimal. The enhancing effect of AgO NPs was observed on cellulase activity (57.804 U/ml/min) at 50 ppm concentration while FeO NPs exhibited an inhibitory effect on cellulase activity at all concentrations. Molecular docking analysis was also performed to understand the underlying mechanism of improved enzymatic activity by nanocatalysts.

CONCLUSION

This study authenticates AgO NPs as better nanocatalysts for improved thermostable cellulase biodegradation activity with the extraordinary capability to be potentially utilized in bioethanol production.

The Recent Advances in the Utility of Microbial Lipases: A Review

Lipases are versatile biocatalysts and are used in different bioconversion reactions. Microbial lipases are currently attracting a great amount of attention due to the rapid advancement of enzyme technology and its practical application in a variety of industrial processes. The current review provides updated information on the different sources of microbial lipases, such as fungi, bacteria, and yeast, their classical and modern purification techniques, including precipitation and chromatographic separation, the immunopurification technique, the reversed micellar system, aqueous two-phase system (ATPS), aqueous two-phase flotation (ATPF), and the use of microbial lipases in different industries, e.g., the food, textile, leather, cosmetics, paper, and detergent industries. Furthermore, the article provides a critical analysis of lipase-producing microbes, distinguished from the previously published reviews, and illustrates the use of lipases in biosensors, biodiesel production, and tea processing, and their role in bioremediation and racemization.

Marine macroalgae polysaccharides-based nanomaterials: an overview with respect to nanoscience applications

Background

Exploration of marine macroalgae poly-saccharide-based nanomaterials is emerging in the nanotechnology field, such as wound dressing, water treatment, environmental engineering, biosensor, and food technology.

Main body

In this article, the current innovation and encroachments of marine macroalgae polysaccharide-based nanoparticles (NPs), and their promising opportunities, for future prospect in different industries are briefly reviewed. The extraction and advancement of various natural sources from marine polysaccharides, including carrageenan, agarose, fucoidan, and ulvan, are highlighted in order to provide a wide range of impacts on the nanofood technology. Further, seaweed or marine macroalgae is an unexploited natural source of polysaccharides, which involves numerous different phytonutrients in the outermost layer of the cell and is rich in sulphated polysaccharides (SP), SP-based nanomaterial which has an enhanced potential value in the nanotechnology field.

Conclusion

At the end of this article, the promising prospect of SP-based NPs and their applications in the food sector is briefly addressed.

Cold-Active Lipases and Esterases: A Review on Recombinant Overexpression and Other Essential Issues

Cold environments characterised by diverse temperatures close to or below the water freezing point dominate about 80% of the Earth's biosphere. One of the survival strategies adopted by microorganisms living in cold environments is their expression of cold-active enzymes that enable them to perform an efficient metabolic flux at low temperatures necessary to thrive and reproduce under those constraints. Cold-active enzymes are ideal biocatalysts that can reduce the need for heating procedures and improve industrial processes' quality, sustainability, and cost-effectiveness. Despite their wide applications, their industrial usage is still limited, and the major contributing factor is the lack of complete understanding of their structure and cold adaptation mechanisms. The current review looked at the recombinant overexpression, purification, and recent mechanism of cold adaptation, various approaches for purification, and three-dimensional (3D) crystal structure elucidation of cold-active lipases and esterase.

Intracellular-to-extracellular localization switch of acidic lipase in Enterobacter cloacae through multi-objective medium optimization: aqueous two-phase purification and activity kinetics

As physiological impairments that require replacement therapy continue to increase, so also does the need for improved production of acidic lipase from new microbial sources. Enterobacter cloacae strain UCCM 00116 produced a novel acidic lipase in kernel oil-processing waste-basal broth with 0.023:1 extracellular: intracellular localization ratio. This research re-directed enzyme localization to the extracellular milieu to reduce recovery cost using multi-objective response surface optimization of medium parameters. Results revealed a 1:0.32 extracellular:intracellular lipase ratio. Product formation kinetics, modeled by the Luedeking-Piret function, showed a significant switch from a completely growth-associated intracellular production to a predominantly non-growth-associated extracellular localization through medium optimization. Aqueous two-phase system purification conditions extracted 95.22% lipase with 72.36 purity, a V_max of 370.37 µmolmin^-1, and a K_m of 0.63 mmol. Enzyme activity was enhanced by K⁺ and Ca²⁺ ions, stable in many organic solvents, except acetone, and had pH and temperature optima at 2.5-3.5 and 50 °C, respectively.

Intracellular-to-extracellular localization switch of acidic lipase in Enterobacter cloacae: evaluation of production kinetics and enantioselective esterification potential for pharmaceutical applications

Downstream processing is a significant part of a production process and accounts for 50-90% of the production cost of biotechnological products. Post-fermentation localization of a microbial metabolite contributes significantly to the recovery cost of the product. Enterobacter cloacae produced naturally, acidic lipase with a 0.023:1 extracellular localization ratio. This research aimed to re-direct the localization of lipase to the extracellular milieu to reduce recovery costs using multi-objective response surface optimization (MO-RSM). The approach resulted in a 1:0.32 extracellular: intracellular lipase ratio, with product formation kinetics of Luedeking-Piret function showing a significant switch from a completely growth-associated intracellular production to a predominantly non-growth-associated extracellular localization. The enzyme was purified by an aqueous two-phase system which extracted 95.22% lipase with 72.36 purity. Characterization of the enzyme showed a molecular weight of 55.7 kDa, kcat of 68.59 s^-1, and a K_m of 0.63 mmol. Lipase activity occurred optimally at pH 2.5-3.5 and 50 °C, and was stable in most organic solvents tested. The acidic lipase demonstrated pH-dependent enantioselective esterification in resolving (R, S)-ibuprofen (E = 14, pH 4.5) and (R, S)-Naproxen (E = 13, pH 2.5), with an enantioselective preference for (S)-enantiomer in both drugs thus underpinning its potential for pharmaceutical applications.

Extremophilic lipases for industrial applications: A general review

With industrialization and development in modern science enzymes and their applications increased widely. There is always a hunt for new proficient enzymes with novel properties to meet specific needs of various industrial sectors. Along with the high efficiency, the green and eco-friendly side of enzymes attracts human attention, as they form a true answer to counter the hazardous and toxic conventional industrial catalyst. Lipases have always earned industrial attention due to the broad range of hydrolytic and synthetic reactions they catalyse. When these catalytic properties get accompanied by features like temperature stability, pH stability, and solvent stability lipases becomes an appropriate tool for use in many industrial processes. Extremophilic lipases offer the same, thermostable: hot and cold active thermophilic and psychrophilic lipases, acid and alkali resistant and active acidophilic and alkaliphilic lipases, and salt tolerant halophilic lipases form excellent biocatalyst for detergent formulations, biofuel synthesis, ester synthesis, food processing, pharmaceuticals, leather, and paper industry. An interesting application of these lipases is in the bioremediation of lipid waste in harsh environments. The review gives a brief account on various extremophilic lipases with emphasis on thermophilic, psychrophilic, halophilic, alkaliphilic, and acidophilic lipases, their sources, biochemical properties, and potential applications in recent decades.

Characterization and genomic analysis of Exiguobacterium alkaliphilum B-3531D, an efficient crude oil degrading strain

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B-3531D is the first E. alkaliphilum strain with fully assembled genome.

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It is the first E. alkaliphilum strain with the ability to utilize crude oil.

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Strain utilized 34.5% of crude oil for 14 days at 28 °C and a salinity of 11%.

The aim of the work was to carry out the physiological, biochemical and genetic characterization of the Exiguobacterium alkaliphilum B-3531D strain. This strain is promising for use in the field of environmental biotechnology, since it has a pronounced ability to utilize crude oil and individual hydrocarbons in a wide temperature range. The genome of the strain was sequenced and completely assembled, it consists of a 2,903,369 bp circular chromosome and two circular plasmids, namely, pE73 (73,590 bp) and pE52 (52,125 bp). When cultivated in a mineral medium containing 2% of crude oil, the strain utilized 50% within 30 days of the experiment. In simulated seawater with the same oil content, the loss of hydrocarbons was 45% over the same period. For the first time we observed in an E. alkaliphilum strain the ability to efficiently utilize crude oil, including with an increased content of sodium chloride in the cultivation medium.