Research progress on chemical composition, pharmacological activity and modern application of Eucommia ulmoides leaves
Eucommia Folium is the dried leaf of Eucommia ulmoides Oliv., a medicinal plant in the Eucommia family. It is now included in the 2020 edition of the Chinese Pharmacopoeia. The leaves of Eucommia ulmoides are elliptical, oval or rectangular in shape, dark green or brown in color, with hairs on the veins and serrated edges. When kneaded, there are sticky threads. Eucommia ulmoides leaves belong to the liver and kidney meridians, and have the effects of nourishing the liver and kidneys, strengthening muscles and bones. They are mainly distributed in Shaanxi, Gansu, Henan, Hubei, and Sichuan provinces in China. Eucommia ulmoides leaves have been recorded and applied in ancient times. The Song Dynasty’s “Compendium of Materia Medica” recorded that Eucommia ulmoides “can be eaten from its young and tender leaves. The Ming Dynasty’s “Compendium of Materia Medica” also cited it, and the Qing Dynasty’s “Guangqunfangpu” also elaborated on the edibility of Eucommia ulmoides leaves based on the explanation in the “Compendium of Materia Medica”. In 2019, the country launched a pilot project for medicinal and edible Eucommia ulmoides leaves, which will be officially included in the list of medicinal and edible Chinese medicines by 2023, indicating that Eucommia ulmoides leaves have high safety and can be developed into health food. In recent years, the development and utilization of Eucommia ulmoides leaves have gradually increased not only in the fields of medicine and food, but also in the fields of animal husbandry and chemical industry, resulting in many relevant literature reports. Although there are many studies on the medicinal plant Eucommia ulmoides, there is limited literature on Eucommia ulmoides leaves. Therefore, this article reviews the research on the chemical composition, pharmacological activity, and modern applications of Eucommia ulmoides leaves at home and abroad from 2003 to 2023, in order to provide reference for in-depth research and resource development of Eucommia ulmoides leaves.

As a traditional Chinese medicine, Eucommia ulmoides leaves have similar chemical composition and efficacy as Eucommia ulmoides. In recent years, Eucommia ulmoides (Eucommia ulmoides bark) has been classified as a vulnerable plant due to its unique medicinal parts, limiting resource development. However, Eucommia ulmoides leaves are abundant in resources and have renewability, making them suitable for large-scale development and utilization. Since 2010, research and development on Eucommia ulmoides leaves has gradually increased due to their high safety and significant effects. Currently, research achievements have expanded from pharmaceuticals, food, and health products to feed additives, chemicals, daily necessities, and other fields, with a good development momentum.
The future research and development of Eucommia ulmoides leaves can focus on the following aspects: (1) During the literature review, it was found that there was no systematic study on Eucommia ulmoides leaves in the early stage of research, and the research conclusions were relatively single. Therefore, in subsequent studies, the chemical composition and pharmacological effects of Eucommia ulmoides leaves can be further combined to clarify the pharmacological substance basis and mechanism of action of Eucommia ulmoides leaves, ensuring the rationality and safety of clinical and daily production applications of Eucommia ulmoides leaves. (2) At present, there have been many studies on the chemical components of Eucommia ulmoides leaves, such as flavonoids and phenolic acids. Further in-depth research should be conducted based on previous studies combined with bioinformatics, molecular biology, and other technologies. However, research on Eucommia ulmoides gum, proteins, trace elements, and other components is relatively blank and should be given special attention in subsequent studies. (3) Eucommia ulmoides leaves are abundant in resources. It is necessary to research and produce Eucommia ulmoides leaf related foods, health products, feed additives, daily chemical products, etc. according to industrial models as soon as possible to create economic benefits and promote the common development of multiple industries such as forestry, processing, and sales.
In summary, the research on drugs, food, health products, and chemical products related to Eucommia ulmoides leaves has great development prospects and value. The successful development and application of Eucommia ulmoides leaves not only alleviates the resource development pressure of Eucommia ulmoides, but also provides new ideas for the development of similar medicinal plants and natural products. Therefore, in subsequent research, efforts should be made to strengthen the development of Eucommia ulmoides leaves and fully tap into their resource value.