Optimized production of lipase from Bacillus subtilis PCSIRNL-39

UV mutagenesis for lipase overproduction from Bacillus cereus ATA179, nutritional optimization, characterization and its usability in the detergent industry

In this study, the wild-type Bacillus cereus ATA179 was mutagenized by random UV mutagenesis to increase lipase production. The mutant with maximum lipolytic activity was named Bacillus cereus EV4. The mutant strain (10.6 U/mL at 24 h) produced 60% more enzyme than the wild strain (6.6 U/mL at 48 h). Nutritional factors on lipase production were investigated. Sucrose was the best carbon source, (NH4)2HPO4 was the best nitrogen source and CuSO4 was the best metal ion source. Mutant EV4 showed a 32% increase in lipase production in the modified medium. The optimum temperature and pH were found to be 60 °C and 7.0, respectively. CuSO4, CaCl2, LiSO4, KCl, BaCl2, and Tween 20 had an activating effect on the enzyme. Vmax and Km values were found to be 17.36 U/mL and 0.036 mM, respectively. The molecular weight was determined as 28.2 kDa. The activity of lipase was found to be stable up to 60 days at 20 °C, 75 days at 4 °C, and 90 days at -20 °C. The potential of lipase in the detergent industry was investigated. The enzyme was not affected by detergent additives but was effective in removing stains in fabrics contaminated with oily substances.

Utilization of microalgae for agricultural runoff remediation and sustainable biofuel production through an integrated biorefinery approach

Generally wastewater such agricultural runoff is considered a nuisance; however, it could be harnessed as a potential source of nutrients like nitrates and phosphates in integrated biorefinery context. In the current study, microalgae Chlorella sp. S5 was used for bioremediation of agricultural runoff and the leftover algal biomass was used as a potential source for production of biofuels in an integrated biorefinery context. The microalgae Chlorella sp. S5 was cultivated on Blue Green (BG 11) medium and a comprehensive optimization of different parameters including phosphates, nitrates, and pH was carried out to acquire maximum algal biomass enriched with high lipids content. Dry biomass was quantified using the solvent extraction technique, while the identification of nitrates and phosphates in agricultural runoff was carried out using commercial kits. The algal extracted lipids (oils) were employed in enzymatic trans-esterification for biodiesel production using whole-cell biomass of Bacillus subtilis Q4 MZ841642. The resultant fatty acid methyl esters (FAMEs) were analyzed using Fourier transform infrared (FTIR) spectroscopy and gas chromatography coupled with mass spectrometry (GC-MS). Subsequently, both the intact algal biomass and its lipid-depleted algal biomass were used for biogas production within a batch anaerobic digestion setup. Interestingly, Chlorella sp. S5 demonstrated a substantial reduction of 95% in nitrate and 91% in phosphate from agricultural runoff. The biodiesel derived from algal biomass exhibited a noteworthy total FAME content of 98.2%, meeting the quality standards set by American Society for Testing and Materials (ASTM) and European union (EU) standards. Furthermore, the biomethane yields obtained from whole biomass and lipid-depleted biomass were 330.34 NmL/g VSadded and 364.34 NmL/g VSadded, respectively. In conclusion, the findings underscore the potent utility of Chlorella sp. S5 as a multi-faceted resource, proficiently employed in a sequential cascade for treating agricultural runoff, producing biodiesel, and generating biogas within the integrated biorefinery concept.

Bioprocessing and Screening of Indigenous Wastes for Hyper Production of Fungal Lipase

Background: Lipase is one of the most important enzymes produced from microbial fermentation. Agricultural wastes are a good source of enzyme production because they are cost-effective and production rates are also higher. Method: In this study, eight lignolitic substrates were screened for lipase production. Results: Out of these substrates, guava leaves showed maximum activity of 9.1 U/mL from Aspergillus niger by using the solid-state fermentation method. Various factors such as temperature, pH, incubation period, moisture content, inoculum size, and substrate size that influence the growth of fungi were optimized by response surface methodology (RSM), and then characterization was performed. When all physical and nutritional parameters were optimized by RSM, the maximum lipase activity obtained was 12.52 U/mL after 4 days of incubation, at pH 8, 40 °C temperature, 3 mL inoculum size, 20% moisture content, and 6 g substrate concentration. The enzyme was partially purified through 70% ammonium sulfate precipitation. After purification, it showed 34.291 U/mg enzyme activity, increasing the purification fold to 1.3. The enzyme was then further purified by dialysis, and the purification fold increased to 1.83 having enzyme activity of 48.03 U/mg. Furthermore, activity was increased to 132.72 U/mg after column chromatography. A purification fold of 5.07 was obtained after all purification steps.

Scale-up Lipase Production and Development of Methanol Tolerant Whole-Cell Biocatalyst from Magnusiomyces spicifer SPB2 in Stirred-Tank Bioreactor and Its Application for Biodiesel Production

This study aimed to economically develop the yeast whole-cell biocatalyst from the lipase-secreting Magnusiomyces spicifer SPB2 to serve green biodiesel production. The scaled-up productions of lipases were optimized using a 5-L stirred-tank bioreactor. The maximum extracellular lipase and cell-bound lipase (CBL) yields of 1189.65 U/L and 5603.74 U/L were achieved at 24 h and 60 h, respectively, in the modified IMY medium (pH 5.0) containing 2% of soybean oil as a carbon source and 0.2% Gum Arabic as an emulsifying agent. The optimized cultivation was initiated with an inoculum size of 1 × 107 cells/mL and conducted under an aeration rate of 0.75 vvm with an agitation speed of 400 rpm. The obtained whole-cell biocatalyst of M. spicifer SPB2 was applied to catalyze the transesterification reaction using palm oil and methanol as substrates. The greatest yield of 97.93% fatty acid methyl ester (FAME) was reached at 72 h using a palm oil/methanol ratio of 1:7, indicating high methanol stability of the biocatalyst. Moreover, substrate homogenization accelerated the reaction to achieve FAME production of 97.01% at 48 h and remained stable afterwards. Without homogenization, the highest FAME of 98.20% was obtained at 60 h. The whole-cell biocatalyst prepared from lipase-secreting M. spicifer SPB2 at an up-scaled level greatly enhanced efficiency and feasibility for commercial biodiesel production through a green conversion process.

Optimization and characterization of alkaliphilic lipase from a novel Bacillus cereus NC7401 strain isolated from diesel fuel polluted soil

Five Bacillus cereus strains including B. cereus AVP12, B. cereus NC7401, B. cereus BDBCO1, B. cereus JF70 and B. specie JL47 isolated from the diesel fuel polluted soil adhered to the roots of Tagetes minuta were screened for lipase production with phenol red agar method. B. cereus NC7401 strain successfully expressing and secreting lipase with maximal lipolytic activity was subjected to a submerged fermentation process with five different carbon (starch, glucose, maltose, fructose, and lactose) and five different nitrogen (tryptone, ammonium nitrate, peptone, urea, yeast extract) sources to produce lipase enzyme. Maximum enzyme activity was found with starch (30.6 UmL-1), maltose (40 UmL-1), and tryptone (38.6 UmL-1), and the lipases produced using these sources were named lipase A, B, and C respectively. The total protein content of 8.56, 8.86, and 2.75 μg mL-1 were obtained from B. cereus NC7401 cultured using starch, maltose, and tryptone respectively. Lipase was stable between temperature range 30–80°C and pH 5–10 whereas optimally active at 55°C and pH 8.0. The enzyme was relatively stable for 10 days at 4°C and its optimum reaction time with the substrate was 30 minutes. It was tolerant to 1.5% (v/v) methanol as an organic solvent, 1.5% (v/v) Triton X-100 as a media additive and 1.5% (w/v) Ni2+ as a metal ion. SDS, n-hexane, and Ag+ inhibited lipolytic activity. Oil stains were removed from cotton fabric which showed oil removal efficiency enhancement in the presence of a lipase. Fat hydrolysis of 20, 24, and 30% was achieved following 6 hours of incubation of the fat particles with lipase A, B, and C respectively at a concentration of 20 mg mL-1. To as best of our knowledge, this study on lipases extracted from bacteria of Azad Kashmir, Pakistan origin has never been reported before.

Homoscleromorpha-derived Bacillus spp. as potential sources of biotechnologically-relevant hydrolases and biosurfactants

Despite hydrolytic exoenzymes and biosurfactants having been gradually reported from the poriferan microbiome, little is known about these bioproducts in microorganisms inhabiting Homoscleromorpha sponges. Here, we investigated the production of hydrolases and biosurfactants in bacteria isolated from three shallow-water homoscleromorph species, Oscarella sp., Plakina cyanorosea, and Plakina cabofriense. A total of 99 of 107 sponge-associated bacterial isolates exhibited activity for at least one of the analyzed hydrolases. Following fermentation in Luria-Bertani (LB) and Tryptic Soy Broth (TSB), two isolates, 80BH11 and 80B1:1010b, showed higher lipase and peptidase activities. Both of them belonged to the Bacillus genus and were isolated from Oscarella. Central composite design leveraged up the peptidase activity in 280% by Bacillus sp. 80BH11 in the TSB medium for 48 h at 30 °C. The optimized model also revealed that pH 6.5 and 45 °C were the best conditions for peptidase reaction. In addition, Bacillus sp. 80BH11 was able to release highly emulsifying and remarkably stable surfactants in the LB medium. Surfactin was finally elucidated as the biosurfactant generated by this sponge-derived Bacillus. In conclusion, we hope to have set the scenery for further prospecting of industrial enzymes and biosurfactants in Homoscleromorpha microbiomes.

Investigation of Lipolytic-Secreting Bacteria from an Artificially Polluted Soil Using a Modified Culture Method and Optimization of Their Lipase Production

Compared to lipases from plants or animals, microbial lipases play a vital role in different industrial applications and biotechnological perspectives due to their high stability and cost-effectiveness. Therefore, numerous lipase producers have been investigated in a variety of environments in the presence of lipidic carbon and organic nitrogen sources. As a step in the development of cultivating the unculturable functional bacteria in this study, the forest soil collected from the surrounding plant roots was used to create an artificially contaminated environment for lipase-producing bacterial isolation. The ten strongest active bacterial strains were tested in an enzyme assay supplemented with metal ions such as Ca2+, Zn2+, Cu2+, Fe2+, Mg2+, K+, Co2+, Mn2+, and Sn2+ to determine bacterial tolerance and the effect of these metal ions on enzyme activity. Lipolytic bacteria in this study tended to grow and achieved a high lipase activity at temperatures of 35-40 °C and at pH 6-7, reaching a peak of 480 U/mL and 420 U/mL produced by Lysinibacillus PL33 and Lysinibacillus PL35, respectively. These potential lipase-producing bacteria are excellent candidates for large-scale applications in the future.

An encapsulated report on enzyme-assisted transesterification with an allusion to lipase

Biodiesel is a renewable, sulfur-free, toxic-free, and low carbon fuel which possesses enhanced lubricity. Transesterification is the easiest method employed for the production of biodiesel, in which the oil is transformed into biodiesel. Biocatalyst-mediated transesterification is more advantageous than chemical process because of its non-toxic nature, the requirement of mild reaction conditions, absence of saponification, easy product recovery, and production of high-quality biodiesel. Lipases are found to be the primary enzymes in enzyme-mediated transesterification process. Currently, researchers are using lipases as biocatalyst for transesterification. Lipases are extracted from various sources such as plants, microbes, and animals. Biocatalyst-based biodiesel production is not yet commercialized due to high-cost of purified enzymes and higher reaction time for the production process. However, research works are growing in the area of various cost-effective techniques for immobilizing lipase to improve its reusability. And further reduction in the production cost of lipases can be achieved by genetic engineering techniques. The reduction in reaction time can be achieved through ultrasonic-assisted biocatalytic transesterification. Biodiesel production by enzymatic transesterification is affected by many factors. Various methods have been developed to control these factors and improve biodiesel production. This report summarizes the various sources of lipase, various production strategies for lipase and the lipase-mediated transesterification. It is fully focused on the lipase enzyme and its role in biodiesel production. It also covers the detailed explanation of various influencing factors, which affect the lipase-mediated transesterification along with the limitations and scope of lipase in biodiesel production.

Identification by molecular techniques of halophilic bacteria producing important enzymes from pristine area in Campeche, Mexico

Isla Arena is located in the coordinate 20° 70´ N - 90° 45´ W, from Campeche, Mexico. In these estuaries, the ocean mixes with fresh water, and ecosystems are concentrated where petenes and pink flamingos proliferate. Crustaceans and mollusks abound in the sea. Despite its enormous marine wealth, there are no studies carried out on which halophilic microorganisms are present in these waters. In this work, the diversity and structure of the microbial community was investigated through a metagenomics approach and corroborated for sequencing of 16S rRNA genes. It was found that the phylum Fimicutes predominates with more than 50%, in almost the same proportion of the class Bacilli and with almost 41% of relative abundance of the order Bacillales. The sequencing results showed that one of the samples presented a high percentage of similarity (99.75%) using the Nucleotide BLAST program with a peculiar microorganism: Bacillus subtilis. This microorganism is one of the best characterized bacteria among the gram-positive ones. Our results demonstrate that B. subtilis can be an efficient source of proteases, lipases and cellulases, from halophilic microbial communities located in poorly explored areas.

Production strategies and biotechnological relevance of microbial lipases: a review

Lipases are enzymes that catalyze the breakdown of lipids into long-chain fatty acids and glycerol in oil-water interface. In addition, they catalyze broad spectrum of bioconversion reactions including esterification, inter-esterification, among others in non-aqueous and micro-aqueous milieu. Lipases are universally produced from plants, animals, and microorganisms. However, lipases from microbial origin are mostly preferred owing to their lower production costs, ease of genetic manipulation etc. The secretion of these biocatalysts by microorganisms is influenced by nutritional and physicochemical parameters. Optimization of the bioprocess parameters enhanced lipase production. In addition, microbial lipases have gained intensified attention for a wide range of applications in food, detergent, and cosmetics industries as well as in environmental bioremediation. This review provides insights into strategies for production of microbial lipases for potential biotechnological applications.

Optimization of Lipase Production from Local Bacteria Isolate with Palm Oil Inducer

A lipase is a group of hydrolase enzymes with multi-functional abilities such as catalyzing hydrolysis, alcoholysis, esterification, interesterification, and synthesis of organic compounds. The purpose of this study was to obtain the optimum conditions for lipase production and to study the effect of adding a palm oil inducer on the production of lipase from local bacterial isolates. The method used in this study included the rejuvenation of local bacterial isolate cultures, optimization of production, which included pH, palm oil inducer, and incubation time. The lipase activity test was carried out by using the acid-base titration method with the phenolphthalein indicator. The results showed that the optimal conditions for lipase production occurred at pH 5 with an activity value of 7.5 U/mL and an incubation time of 18 hours with an activity value of 13.83 U/mL. The addition of a 10% (v/v) palm oil inducer increased the value of lipase activity to 8.75 U/mL. 

Microbial Enzymes Used in Bioremediation

Emerging pollutants in nature are linked to various acute and chronic detriments in biotic components and subsequently deteriorate the ecosystem with serious hazards. Conventional methods for removing pollutants are not efficient; instead, they end up with the formation of secondary pollutants. Significant destructive impacts of pollutants are perinatal disorders, mortality, respiratory disorders, allergy, cancer, cardiovascular and mental disorders, and other harmful effects. The pollutant substrate can recognize different microbial enzymes at optimum conditions (temperature/pH/contact time/concentration) to efficiently transform them into other rather unharmful products. The most representative enzymes involved in bioremediation include cytochrome P450s, laccases, hydrolases, dehalogenases, dehydrogenases, proteases, and lipases, which have shown promising potential degradation of polymers, aromatic hydrocarbons, halogenated compounds, dyes, detergents, agrochemical compounds, etc. Such bioremediation is favored by various mechanisms such as oxidation, reduction, elimination, and ring-opening. The significant degradation of pollutants can be upgraded utilizing genetically engineered microorganisms that produce many recombinant enzymes through eco-friendly new technology. So far, few microbial enzymes have been exploited, and vast microbial diversity is still unexplored. This review would also be useful for further research to enhance the efficiency of degradation of xenobiotic pollutants, including agrochemical, microplastic, polyhalogenated compounds, and other hydrocarbons.

High-level expression of lipase from Galactomyces geotrichum mafic-0601 by codon optimization in Pichia pastoris and its application in hydrolysis of various oils

A Galactomyces geotrichum strain with lipolytic activity was isolated and identified by the analysis of internal transcribed spacer (ITS) sequence of 18 s rDNA. Full-length lipase gene of this stain is composed of 1692 base pairs (bp) without intron, which encodes a 563-amino-acid protein. A catalytic triad (Ser²¹⁷-Glu³⁵⁴-His⁴⁶³) was found by constructing the three-dimensional structure of the lipase. In shake flasks, the lipase (LIP) catalytic activity in the supernatant of the recombinant Pichia pastoris increased 48.7% by codon optimization. LIP purified by anion exchange column showed a single protein band on 12% SDS-PAGE. The molecular weight (MW) of LIP was approximately 62 kDa. The specific activity of purified LIP reached 1257.9 U/mg. The optimum temperature and pH of LIP catalysis were 45 °C and pH 8.2, respectively. LIP was stable over the pH range of 4.2-11.2. LIP maintained its activity constantly at 40 °C and 50 °C for 120 min. Zn²⁺ inhibited LIP activity; Ba²⁺, Mn²⁺, Ca²⁺ and EDTA increased the enzyme activity. Referring the amount of hydrolyzed olive oil by LIP as 100%, various oils including lard, peanut oil, rapeseed oil, sunflower oil, soybean oil and linseed oil were efficiently hydrolyzed by 17.24 ± 1.34%, 40.34 ± 2.56%, 105.86 ± 2.78%, 115.51 ± 2.32%, 116.21 ± 2.15%, 120.69 ± 1.98%, respectively. The characteristics allow LIP as a potential biocatalyst in various fields of industry.

Production of Cold-Active Lipase by Free and Immobilized Marine Bacillus cereus HSS: Application in Wastewater Treatment

Lipases are enzymes that have the potential to hydrolyze triacylglycerol to free fatty acids and glycerol and have various applications. The aim of the present study was to isolate and screen marine bacteria for lipase production, optimize the production, and treat wastewater. A total of 20 marine bacterial isolates were obtained from the Mediterranean Sea and were screened for lipase production. All isolates were found to have lipolytic ability. The differences between the isolates were studied using RAPD-PCR. The most promising lipase producer (isolate 3) that exhibited the highest lipolytic hydrolysis (20 mm) was identified as Bacillus cereus HSS using 16S rDNA analysis and had the accession number MF581790. Optimization of lipase production was carried out using the Plackett-Burman experimental design with cotton seed oil as the inducer under shaking conditions at 10°C. The most significant factors that affected lipase production were FeSO4, KCl, and oil concentrations. By using the optimized culture conditions, the lipase activity increased by 1.8-fold compared with basal conditions. Immobilization by adsorption of cells on sponge and recycling raised lipase activity by 2.8-fold compared with free cells. The repeated reuse of the immobilized B. cereus HSS maintained reasonable lipase activity. A trial for the economic treatment of oily wastewater was carried out. Removal efficiencies of biological oxygen demand, total suspended solids, and oil and grease were 87.63, 90, and 94.7%, respectively, which is promising for future applications.