What is the research progress of biocatalytic synthesis of propylene oxide?

Biocatalytic Synthesis of Propylene Oxide

Propylene oxide (PO) is an important basic chemical raw material, which is widely used in polyurethane, epoxy resin, surfactant and other fields. Traditional propylene oxide production methods rely mainly on petrochemical routes, such as propylene oxidation and chloropropane processes. These methods have the problems of high energy consumption, high pollution and non-renewable resources, which limit their sustainable development. In recent years, with the rise of green chemistry and biocatalysis, biocatalytic synthesis of propylene oxide has gradually become a research hotspot. This paper will systematically analyze the research progress of biocatalytic synthesis of propylene oxide from three aspects: research status, key challenges and future development direction.

1. biocatalytic synthesis of propylene oxide

Biocatalysis is a technology that uses enzymes or microorganisms to convert substrates into target products under mild conditions. In the biosynthesis of propylene oxide, researchers mainly focus on the following two methods: enzymatic and microbial conversion.

1. enzyme catalytic method Enzymatic catalysis is the conversion of simple substrates (such as propylene or propylene glycol) into propylene oxide by specific enzymes (such as cyclooxygenase, peroxidase, etc.) catalyzing reactions in vitro or in vivo. For example, propylene oxide can be produced from propylene glycol under the catalysis of propylene oxide synthase (PO synthase). This method has the advantages of mild reaction conditions, high selectivity and few side reactions. In recent years, researchers have modified epoxy propane synthase by genetic engineering technology, which has significantly improved the activity and stability of the enzyme, and greatly improved the conversion rate and yield of the product.

2. microbial transformation method Microbial transformation method is the use of engineered microorganisms (such as yeast, Escherichia coli, etc.) in the fermentation process of direct synthesis of propylene oxide. Microorganisms contain a variety of enzymes, which can achieve efficient synthesis of propylene oxide through the optimization of metabolic pathways. For example, simple carbon sources such as glucose can be converted to propylene oxide by introducing propylene oxide synthase through genetic engineering techniques. The advantage of this method is that renewable resources (such as biomass) can be used as substrates, which meets the requirements of sustainable development.

2. Biocatalytic Synthesis of Propylene Oxide: Key Challenges

Although the biocatalytic method shows great potential in the synthesis of propylene oxide, it still faces some key challenges.

1. optimization of reaction conditions Biocatalytic reactions usually need to be carried out under mild conditions, which puts higher requirements on the efficiency and cost of the reaction. For example, the optimization of reaction temperature, pH value, substrate concentration and other parameters directly affect the conversion and yield of the product. The stability of the enzyme is also an important issue, especially in the environment of high temperature, high humidity or high concentration of substrate, the activity of the enzyme is easily inhibited or inactivated.

2. Catalyst Development and Cost As the core of biocatalysis, the cost and availability of enzymes directly affect the economy of the process. At present, many enzymes used for propylene oxide synthesis need to be expressed in large quantities in microorganisms through genetic engineering technology, which not only requires high research and development costs, but also needs to solve the problem of efficient separation and purification of enzymes. The catalytic efficiency and stability of some enzymes have not yet reached the requirements of industrialization, which is also an important factor restricting the large-scale application of biocatalysis.

3. biocatalytic synthesis of propylene oxide in the future

In response to the above challenges, future research will focus on the following three areas:

1. Modification and Optimization of Enzyme The catalytic efficiency and stability of the enzyme were improved by site-directed mutagenesis, rational design and system optimization through genetic engineering technology. For example, researchers can use molecular simulation and computational biology to analyze the interaction mechanism between enzymes and substrates, so as to design more efficient enzyme variants.

2. Development of new catalysts In addition to traditional enzyme catalysis, researchers can also explore other types of biocatalysts, such as cell membrane immobilized enzymes, nano-enzymes, etc. These new catalysts can not only improve the reaction efficiency, but also realize the reuse of the catalyst through the immobilization technology and reduce the production cost.

3. Green Technology and Sustainable Development An important advantage of biocatalysis is its green and environmentally friendly characteristics. Future research will pay more attention to the use of renewable resources (such as biomass) as substrates, and optimize the metabolic pathways of microorganisms through metabolic engineering and systems biology to achieve efficient and low-cost synthesis of propylene oxide.

4. conclusion

As a green and sustainable production technology, biocatalytic synthesis of propylene oxide has incomparable advantages over traditional petrochemical routes. Although there are still challenges such as optimization of reaction conditions, catalyst development and cost control, these problems will be gradually solved with the rapid development of genetic engineering, metabolic engineering and computational biology. In the future, biocatalytic method is expected to become an important technical route for the synthesis of propylene oxide, providing new solutions for the sustainable development of the chemical industry.