A novel halophilic extracellular lipase with both hydrolytic and synthetic activities

Halophilic Fungi-Features and Potential Applications

Extremophiles are of significant scientific interest due to their unique adaptation to harsh environmental conditions and their potential for diverse biotechnological applications. Among these extremophiles, filamentous fungi adapted to high-salt environments represent a new and valuable source of enzymes, biomolecules, and biomaterials. While most studies on halophiles have focused on bacteria, reports on filamentous fungi remain limited. This review compiles information about salt-adapted fungi and details their distribution, adaptation mechanisms, and potential applications in various societal areas. Understanding the adaptive mechanisms of halophilic fungi not only sheds light on the biology of extremophilic fungi but also leads to promising biotechnological applications, including the development of salt-tolerant enzymes and strategies for bioremediation of saline habitats. To fully realize this potential, a comprehensive understanding of their ecology, diversity and physiology is crucial. In addition, understanding their survival mechanisms in saline environments is important for the development of astrobiology. The significant potential of applications of halophilic fungi is highlighted.

Comprehensive Insights into Microbial Lipases: Unveiling Structural Dynamics, Catalytic Mechanism, and Versatile Applications

Microbial lipases (MLs) are pivotal biocatalysts in lipid biotechnology due to their diverse enzymatic properties and substrate specificity, garnering significant research attention. This comprehensive review explores the significance of MLs in biocatalysis, providing insights into their structure, catalytic domain, and oxyanion hole. The catalytic mechanism is elucidated, highlighting the molecular processes driving their efficiency. The review delves into ML sources, spanning fungi, yeasts, bacteria, and actinomycetes, followed by a discussion on classification and characterization. Emphasizing the scattered findings in the literature, the paper consolidates the latest information on ML applications across various industries, from food and pharmaceuticals to biofuel production and the paper and pulp industry. The review captures the dynamic landscape of ML research, emphasizing their structure-function relationships and practical implications across diverse sectors.

Influence of Salinity on the Extracellular Enzymatic Activities of Marine Pelagic Fungi

Even though fungi are ubiquitous in the biosphere, the ecological knowledge of marine fungi remains rather rudimentary. Also, little is known about their tolerance to salinity and how it influences their activities. Extracellular enzymatic activities (EEAs) are widely used to determine heterotrophic microbes' enzymatic capabilities and substrate preferences. Five marine fungal species belonging to the most abundant pelagic phyla (Ascomycota and Basidiomycota) were grown under non-saline and saline conditions (0 g/L and 35 g/L, respectively). Due to their sensitivity and specificity, fluorogenic substrate analogues were used to determine hydrolytic activity on carbohydrates (β-glucosidase, β-xylosidase, and N-acetyl-β-D-glucosaminidase); peptides (leucine aminopeptidase and trypsin); lipids (lipase); organic phosphorus (alkaline phosphatase), and sulfur compounds (sulfatase). Afterwards, kinetic parameters such as maximum velocity (Vmax) and half-saturation constant (Km) were calculated. All fungal species investigated cleaved these substrates, but some species were more efficient than others. Moreover, most enzymatic activities were reduced in the saline medium, with some exceptions like sulfatase. In non-saline conditions, the average Vmax ranged between 208.5 to 0.02 μmol/g biomass/h, and in saline conditions, 88.4 to 0.02 μmol/g biomass/h. The average Km ranged between 1553.2 and 0.02 μM with no clear influence of salinity. Taken together, our results highlight a potential tolerance of marine fungi to freshwater conditions and indicate that changes in salinity (due to freshwater input or evaporation) might impact their enzymatic activities spectrum and, therefore, their contribution to the oceanic elemental cycles.

A Valuable Product of Microbial Cell Factories: Microbial Lipase

As a powerful factory, microbial cells produce a variety of enzymes, such as lipase. Lipase has a wide range of actions and participates in multiple reactions, and they can catalyze the hydrolysis of triacylglycerol into its component free fatty acids and glycerol backbone. Lipase exists widely in nature, most prominently in plants, animals and microorganisms, among which microorganisms are the most important source of lipase. Microbial lipases have been adapted for numerous industrial applications due to their substrate specificity, heterogeneous patterns of expression and versatility (i.e., capacity to catalyze reactions at the extremes of pH and temperature as well as in the presence of metal ions and organic solvents). Now they have been introduced into applications involving the production and processing of food, pharmaceutics, paper making, detergents, biodiesel fuels, and so on. In this mini-review, we will focus on the most up-to-date research on microbial lipases and their commercial and industrial applications. We will also discuss and predict future applications of these important technologies.

The Occurrence of Triple Catalytic Characteristics of Yeast Lipases and Their Application Prospects in Biodiesel Production from Non-Edible Jatropha curcas Oil in a Solvent-Free System

Extracellular and cell-bound lipase-producing yeasts were isolated from the palm oil mill wastes and investigated for their potential uses as biocatalysts in biodiesel production. Twenty-six yeast strains were qualitatively screened as lipase producers. From those yeast strains, only six were selected and screened further for quantitative lipase production.The phylogenetic affiliations of the yeast strains were confirmed by investigating the D1/D2 domains of 26S rDNA and ITS1-5.8S-ITS2 molecular regions of the six yeast strains selected as potent lipase producers. The three yeast strains A4C, 18B, and 10F showed a close association with Magnusiomyces capitatus. Two yeast strains (17B and AgB) had a close relationship with Saprochaete clavata, whereas the strain AW2 was identified as Magnusiomyces spicifer. Three main catalytic activities of the yeast lipases were evaluated and Magnusiomyces capitatus A4C, among the selected lipase-producing yeasts, had the highest extracellular lipolytic enzyme activity (969 U/L) with the cell-bound lipolytic enzyme activity of 11.3 U/gdm. The maximum cell-bound lipolytic activity (12.4 U/gdm) was observed in the cell-bound lipase fraction produced by Magnusiomyces spicifer AW2 with an extracellular lipolytic enzyme activity of 886 U/L. Based on the specific hydrolytic enzymatic activities, the cell-bound lipases (CBLs) from the three yeast strains M. capitatus A4C, M. spicifer AW2, and Saprochaete clavata 17B were further investigated for biodiesel production. Among them, the CBL from M. spicifer AW2 synthesized the most FAME (fatty acid methyl esters) at 81.2% within 12 h indicating that it has potential for application in enzymatic biodiesel production.

Optimization of novel halophilic lipase production by Fusarium solani strain NFCCL 4084 using palm oil mill effluent

Among different sources of lipases, fungal lipases have continued to attract a wide range of applications. Further, halophilic lipases are highly desirable for biodiesel production due to the need to mitigate environmental pollution caused as result of extensive use of fossil fuels. However, currently, the high production cost limits the industrial application of lipases. In order to address this issue, we have attempted to optimize lipase production by Fusarium solani NFCCL 4084 and using palm oil mill effluent (POME) based medium. The production was optimized using a combinatory approach of Plackett-Burman (PB) design, one factor at a time (OFAT) design and face centred central composite design (FCCCD). The variables (malt extract, (NH4)2SO4, CaCl2, MgSO4, olive oil, peptone, K2HPO4, NaNO3, Tween-80, POME and pH) were analyzed using PB design and the variables with positive contrast coefficient were found to be K2HPO4, NaNO3, Tween-80, POME and pH. The significant variables selected were further analyzed for possible optimum range by using OFAT approach and the findings revealed that K2HPO4, NaNO3, and Tween-80 as the most significant medium components, and thus were further optimized by using FCCCD. The optimum medium yielded a lipase with an activity of 7.8 U/ml, a significant 3.2-fold increase compared to un-optimized medium. The present findings revealed that POME is an alternative and suitable substrate for halophilic lipase production at low cost. Also, it is clearly evident that the combinatory approach employed here proved to be very effective in producing high activity halophilic lipases, in general.