Arbutins are a kind of natural glycoside compounds found widely in nature. α-arbutin, one of its isomers, has received increasing market attention due to its efficient and safe whitening effect and other excellent pharmacological effects. Studies have revealed that the production methods of α-arbutin mainly fall into three categories: plant extraction, chemical synthesis, and biosynthesis. For the plant extraction, raw materials are widely available, and the process is simple, but the yield fails to meet the requirement for large scale production and applications. The chemical synthesis has a higher yield but with harsh reaction conditions, and thus is not environmentally friendly. Through research has found that the biosynthesis of α-arbutin has higher yield, safer environment, more competitive cost and other advantages compared with the natural extraction and chemical synthesis as well, making it the mainstream production method. This article discusses the advantages and disadvantages of different synthetic methods and studies on the seven enzymes commonly used in the biosynthesis of α-arbutin including α-amylase, sucrose phosphorylase, cyclodextrin glycosyltransferase, α-glucosylase, dextransucrase, amylosucrase, and sucrose isomerase. These enzymes use different sugar donors and catalyze the transglycosylation reaction with hydroquinone as the receptor substrate to synthesize α-arbutin. Additionally, we provide a comprehensive review on research progress in the whole-cell catalysis and microbial fermentation to produce α-arbutin, and potentials for its industrial production are assessed. Furthermore, we highlight challenges that exist in the biosynthesis of α-arbutin, such as the oxidation of hydroquinone during synthesis that increases cell toxicity and reduces the yield, the low utilization rate of glucose and the generation of other glycoside products, and the poor performance of experimental strains, and corresponding solutions are proposed. Finally, future directions for α-arbutin synthesis are prospected, with the aim of providing new ideas for achieving more efficient and lower-cost production of α-arbutin and enhancing its applications in the fields of cosmetics and medicines.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |