Study on the Chemical Composition and α – Glucosidase Inhibition Activity of Chinese Cypress
Selaginella prolata H.S. Kung is a perennial herbaceous plant belonging to the family Selaginella and the genus Selaginella. It often grows in crevices at elevations of 1500-2500 meters or on mossy rocks under forests. It is distributed in provinces such as Guizhou, Yunnan, and Sichuan. The whole plant of Quercus acutissima can be used for medicinal purposes. After drying or burning it into charcoal, grind it into powder and mix it with tea oil. It can be applied externally to stop bleeding; Stewed wine for oral consumption can treat injuries, amenorrhea, blood stasis, and other symptoms. In addition, the ground roller cypress also has high ornamental value and can be cultivated for viewing.
The genus Selaginella has a wide variety of plant species and abundant resources, with about 700 species worldwide, mainly produced in tropical regions. Among them, there are about 70 species in China, which are widely distributed throughout the country. More than 20 species of plants such as Yanzhou Selaginella and Jiangnan Selaginella have been widely used as traditional folk medicines. As official medications, there are two types of Chinese medicinal herbs: Selaginella sinensis and cushion shaped Selaginella chinensis, both of which are included in the 2020 edition of the Pharmacopoeia of the People’s Republic of China. They have the effects of removing blood stasis, stopping bleeding, promoting blood circulation, and promoting menstruation. They can be used for the treatment of diseases such as falls, menstrual cramps, vomiting, and diarrhea. Modern research has shown that plants of the Selaginella genus contain various chemical components such as flavonoids, lignans, alkynes, and terpenes, which have effects such as lowering blood sugar, antioxidation, anti-aging, anti-tumor, anti-inflammatory, and antibacterial. At present, research on the genus Selaginella at home and abroad mainly focuses on several plants such as Selaginella, Chinese Selaginella, and Jiangnan Selaginella, with relatively little research on other plants in the genus. The ground roller cypress belongs to the genus Selaginella, and so far there have been no literature reports on its chemical composition and pharmacological activity. In order to further clarify and explore the medicinal value and active substance basis of Quercus acutissima, this paper studied the chemical composition of the 95% ethanol extract of Quercus acutissima, and evaluated the enzyme inhibitory activity of the isolated compounds in vitro, in order to lay a scientific foundation for the rational development and utilization of Quercus acutissima plant resources.

This article uses various modern chromatographic separation techniques and spectroscopic methods to study the chemical composition and biological activity of Quercus acutissima. Ten compounds were isolated and identified from the 95% ethanol extract of Quercus acutissima, including four sesquiterpenes, three lignans, and three flavonoids. Among them, compound 1 is a new sesquiterpene compound, and compounds 2-10 were isolated for the first time from Quercus acutissima. The PNPG method was used to test the α – glucosidase inhibitory activity of all compounds, and the results showed that flavonoids 8-10 had good α – glucosidase inhibitory activity. Based on this, it is speculated that flavonoids may be an important material basis for the hypoglycemic activity of Platycodon grandiflorus. This article reveals for the first time the active ingredients that inhibit alpha glucosidase in Quercus acutissima, enriching the chemical composition of Quercus acutissima and providing reference and scientific basis for further development and utilization of this plant resource.