scholarly journals Improved methanol tolerance of Rhizomucor miehei lipase based on N‑glycosylation within the α-helix region and its application in biodiesel production

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Miao Tian ◽  
Lingmei Yang ◽  
Zhiyuan Wang ◽  
Pengmei Lv ◽  
Junying Fu ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Rational Design ◽  
Rhizomucor Miehei ◽  
Raw Material ◽  
Biodiesel Production ◽  
High Catalytic Activity ◽  
Single Chain ◽  
Methanol Tolerance ◽  
First Choice ◽  
Α Helix

Abstract Background Liquid lipases are widely used to convert oil into biodiesel. Methanol-resistant lipases with high catalytic activity are the first choice for practical production. Rhizomucor miehei lipase (RML) is a single-chain α/β-type protein that is widely used in biodiesel preparation. Improving the catalytic activity and methanol tolerance of RML is necessary to realise the industrial production of biodiesel. Results In this study, a semi-rational design method was used to optimise the catalytic activity and methanol tolerance of ProRML. After N-glycosylation modification of the α-helix of the mature peptide in ProRML, the resulting mutants N218, N93, N115, N260, and N183 increased enzyme activity by 66.81, 13.54, 10.33, 3.69, and 2.39 times than that of WT, respectively. The residual activities of N218 and N260 were 88.78% and 86.08% after incubation in 50% methanol for 2.5 h, respectively. In addition, the biodiesel yield of all mutants was improved when methanol was added once and reacted for 24 h with colza oil as the raw material. N260 and N218 increased the biodiesel yield from 9.49% to 88.75% and 90.46%, respectively. Conclusions These results indicate that optimising N-glycosylation modification in the α-helix structure is an effective strategy for improving the performance of ProRML. This study provides an effective approach to improve the design of the enzyme and the properties of lipase mutants, thereby rendering them suitable for industrial biomass conversion.

scholarly journals Bio-Derived Catalysts: A Current Trend of Catalysts Used in Biodiesel Production

Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 812
Author(s):  
Hoang Chinh Nguyen ◽  
My-Linh Nguyen ◽  
Chia-Hung Su ◽  
Hwai Chyuan Ong ◽  
Horng-Yi Juan ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Fossil Fuels ◽  
Current Trend ◽  
Biodiesel Production ◽  
High Catalytic Activity ◽  
Promising Alternative ◽  
Advantages And Disadvantages ◽  
Biodiesel Synthesis ◽  
Alkali Catalysts ◽  
A Current

Biodiesel is a promising alternative to fossil fuels and mainly produced from oils/fat through the (trans)esterification process. To enhance the reaction efficiency and simplify the production process, various catalysts have been introduced for biodiesel synthesis. Recently, the use of bio-derived catalysts has attracted more interest due to their high catalytic activity and ecofriendly properties. These catalysts include alkali catalysts, acid catalysts, and enzymes (biocatalysts), which are (bio)synthesized from various natural sources. This review summarizes the latest findings on these bio-derived catalysts, as well as their source and catalytic activity. The advantages and disadvantages of these catalysts are also discussed. These bio-based catalysts show a promising future and can be further used as a renewable catalyst for sustainable biodiesel production.

Towards rational design of core–shell catalytic nanoreactor with high performance catalytic hydrogenation of levulinic acid

2016 ◽  
Vol 6 (13) ◽  
pp. 5102-5115 ◽  
Author(s):  
Biplab Banerjee ◽  
Ramana Singuru ◽  
Sudipta K. Kundu ◽  
Karnekanti Dhanalaxmi ◽  
Linyi Bai ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Catalytic Hydrogenation ◽  
Levulinic Acid ◽  
High Performance ◽  
Rational Design ◽  
Core Shell ◽  
High Catalytic Activity

Core–shell catalytic nanoreactor was designed, exhibiting high catalytic activity for levulinic acid hydrogenation.

scholarly journals Biodiesel Production over Niobium-Containing Catalysts: A Review

Energies ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5506
Author(s):  
Daniel Carreira Batalha ◽  
Márcio José da Silva
Keyword(s):  
Catalytic Activity ◽  
Active Sites ◽  
Heterogeneous Catalysts ◽  
Raw Materials ◽  
Catalytic Performance ◽  
High Specific Surface Area ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Main Reaction ◽  
High Catalytic Activity

Nowadays, the synthesis of biofuels from renewable raw materials is very popular. Among the various challenges involved in improving these processes, environmentally benign catalysts compatible with an inexpensive feedstock have become more important. Herein, we report the recent advances achieved in the development of Niobium-containing heterogeneous catalysts as well as their use in routes to produce biodiesel. The efficiency of different Niobium catalysts in esterification and transesterification reactions of lipids and oleaginous raw materials was evaluated, considering the effect of main reaction parameters such as temperature, time, catalyst load, and oil:alcohol molar ratio on the biodiesel yield. The catalytic performance of Niobium compounds was discussed considering the characterization data obtained by different techniques, including NH3-TPD, BET, and Pyr-FT-IR analysis. The high catalytic activity is attributed to its inherent properties, such as the active sites distribution over a high specific surface area, strength of acidity, nature, amount of acidic sites, and inherent mesoporosity. On top of this, recycling experiments have proven that most Niobium catalysts are stable and can be repeatedly used with consistent catalytic activity.

Utilization of Waste Enamel Venus Shell as Friendly Environmental Catalyst for Synthesis of Biodiesel

2015 ◽  
Vol 659 ◽  
pp. 237-241 ◽  
Author(s):  
Achanai Buasri ◽  
Teera Sriboonraung ◽  
Kittika Ruangnam ◽  
Pattarapon Imsombati ◽  
Vorrada Loryuenyong
Keyword(s):  
Catalytic Activity ◽  
Waste Material ◽  
Raw Material ◽  
Biodiesel Production ◽  
Molar Ratio ◽  
Catalyst Loading ◽  
X Ray ◽  
Environmental Catalyst ◽  
Gas Chromatograph Mass Spectrometry ◽  
Alkali Catalysts

Calcium oxide (CaO) is one of the most promising heterogeneous alkali catalysts since it is cheap, abundantly available in nature, and some of the sources of this compound are renewable (waste material consisting of calcium carbonate (CaCO3)). In this study, the waste enamel venus shell was used as the raw material for CaO catalyst. The calcination of bio-waste was conducted at 900 °C for 2 h. The raw material and the resulting CaO catalyst were characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and the Brunauer-Emmett-Teller (BET) method. The effects of reaction variables such as reaction time, microwave power, methanol/oil molar ratio, and catalyst loading on the yield of biodiesel were investigated by gas chromatograph-mass spectrometry (GC-MS). From the experimental results, it was found that the CaO catalysts derived from waste material showed good catalytic activity (the conversion of oil of nearly 93%, a very similar catalytic activity with laboratory CaO) and had high potential to be used as biodiesel production catalysts in transesterification of Jatropha Curcas oil with methanol.

Self-solidification ionic liquids as heterogeneous catalysts for biodiesel production

2019 ◽  
Vol 21 (11) ◽  
pp. 3182-3189 ◽  
Author(s):  
Xiaocheng Lin ◽  
Xiaomei Ling ◽  
Jinyi Chen ◽  
Meichen Li ◽  
Tongwen Xu ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Ionic Liquids ◽  
Heterogeneous Catalysts ◽  
Biodiesel Production ◽  
High Catalytic Activity ◽  
Excellent Stability

A simple and mild method has been developed to fabricate solid ionic liquids with high catalytic activity and excellent stability for efficient biodiesel production.

scholarly journals Enhancing the Thermostability of Rhizomucor miehei Lipase with a Limited Screening Library by Rational-Design Point Mutations and Disulfide Bonds

2017 ◽  
Vol 84 (2) ◽  
Author(s):  
Guanlin Li ◽  
Xingrong Fang ◽  
Feng Su ◽  
Yuan Chen ◽  
Li Xu ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Disulfide Bonds ◽  
Rational Design ◽  
Single Point ◽  
Point Mutations ◽  
Rhizomucor Miehei ◽  
Wild Type ◽  
Content Type ◽  
Eukaryotic Protein ◽  
Screening Library

ABSTRACT Rhizomucor miehei lipase (RML), as a kind of eukaryotic protein catalyst, plays an important role in the food, organic chemical, and biofuel industries. However, RML retains its catalytic activity below 50°C, which limits its industrial applications at higher temperatures. Soluble expression of this eukaryotic protein in Escherichia coli not only helps to screen for thermostable mutants quickly but also provides the opportunity to develop rapid and effective ways to enhance the thermal stability of eukaryotic proteins. Therefore, in this study, RML was engineered using multiple computational design methods, followed by filtration via conservation analysis and functional region assessment. We successfully obtained a limited screening library (only 36 candidates) to validate thermostable single point mutants, among which 24 of the candidates showed higher thermostability and 13 point mutations resulted in an apparent melting temperature ( T m app ) of at least 1°C higher. Furthermore, both of the two disulfide bonds predicted from four rational-design algorithms were further introduced and found to stabilize RML. The most stable mutant, with T18K/T22I/E230I/S56C-N63C/V189C-D238C mutations, exhibited a 14.3°C-higher T m app and a 12.5-fold increase in half-life at 70°C. The catalytic efficiency of the engineered lipase was 39% higher than that of the wild type. The results demonstrate that rationally designed point mutations and disulfide bonds can effectively reduce the number of screened clones to enhance the thermostability of RML. IMPORTANCE R. miehei lipase, whose structure is well established, can be widely applied in diverse chemical processes. Soluble expression of R. miehei lipase in E. coli provides an opportunity to explore efficient methods for enhancing eukaryotic protein thermostability. This study highlights a strategy that combines computational algorithms to predict single point mutations and disulfide bonds in RML without losing catalytic activity. Through this strategy, an RML variant with greatly enhanced thermostability was obtained. This study provides a competitive alternative for wild-type RML in practical applications and further a rapid and effective strategy for thermostability engineering.

Ultrasonic-assisted biodiesel production from waste cooking oil over novel sulfonic functionalized carbon spheres derived from cyclodextrin via one-step: a way to produce biodiesel at short reaction time

RSC Advances ◽  
2015 ◽  
Vol 5 (68) ◽  
pp. 55252-55261 ◽  
Author(s):  
Panya Maneechakr ◽  
Jittima Samerjit ◽  
Surachai Karnjanakom
Keyword(s):  
Catalytic Activity ◽  
Reaction Time ◽  
Waste Cooking Oil ◽  
Biodiesel Production ◽  
High Catalytic Activity ◽  
Carbon Spheres ◽  
Short Reaction Time ◽  
Cooking Oil ◽  
Ultrasonic Assisted ◽  
One Step

A novel sulfonated carbon derived from cyclodextrin showed high catalytic activity for the ultrasonic-assisted transesterification of waste cooking oil.

scholarly journals Cyclodextrin polymer networks decorated with subnanometer metal nanoparticles for high-performance low-temperature catalysis

2019 ◽  
Vol 5 (11) ◽  
pp. eaax6976 ◽  
Author(s):  
Tiefan Huang ◽  
Guan Sheng ◽  
Priyanka Manchanda ◽  
Abdul H. Emwas ◽  
Zhiping Lai ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Metal Nanoparticles ◽  
Rational Design ◽  
Polymer Network ◽  
Polymer Networks ◽  
Coupling Reaction ◽  
High Catalytic Activity ◽  
Support Materials ◽  
Cyclodextrin Polymer ◽  
Coordination Sites

The synthesis of support materials with suitable coordination sites and confined structures for the controlled growth of ultrasmall metal nanoparticles is of great importance in heterogeneous catalysis. Here, by rational design of a cross-linked β-cyclodextrin polymer network (CPN), various metal nanoparticles (palladium, silver, platinum, gold, and rhodium) of subnanometer size (<1 nm) and narrow size distribution are formed via a mild and facile procedure. The presence of the metal coordination sites and the network structure are key to the successful synthesis and stabilization of the ultrasmall metal nanoparticles. The as-prepared CPN, loaded with palladium nanoparticles, is used as a heterogeneous catalyst and shows outstanding catalytic performance in the hydrogenation of nitro compounds and Suzuki-Miyaura coupling reaction under mild conditions. The CPN support works synergistically with the metal nanoparticles, achieving high catalytic activity and selectivity. In addition, the catalytic activity of the formed catalyst is controllable.

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