## 1 Introduction  
WST comes from the Three Gorges Basin of the Yangtze River in Wushan, Chongqing, China. This tea is mainly made from the young leaves of native wild _Malus hupehensis_ (Pamp.) Rehd., and its leaves grow on the top of cliffs in a primeval, pollution-free forest environment. These raw leaves are dried at the appropriate temperature and humidity, and with their own fermentation and a series of complex chemical changes, they form a unique flavor and mouthfeel. This tea is also known as \"longevity tea\" by the local people [1]. The raw leaves used for processing this tea was reported to contain a variety of trace elements beneficial to the human body as well as multiple amino acids and flavonoids, and it has demonstrated many health functions, including weight loss, lowering of blood pressure, soothing of nerves, strengthening of teeth, bacteriostasis, cancer prevention, anti-aging, and improved immunity [2; 3]. However, the functional application scope of WST is still relatively unclear; there is little research about its extracts on functional effect, and even less research on its specific active compounds. This research is the first to study the functions and potential active compounds of WST.  
The aerobic metabolism of the human body is inseparable from energy conversion, and free radicals serve as carriers during energy transfer. Free radicals are independent chemical substances with unpaired electrons, and when the amount of free radicals exceeds the range of the antioxidant protection system, excessive oxidation occurs, promoting free radicals to attack the cells of the body to acquire electrons in order to maintain their own stability, causing damage to the conformation and function of cells and triggering inflammation, molecular degradation, and other types of diseases, such as cardiovascular disease, neurologic disease, and cancer [4; 5]. In addition to the body's own resistance system (such as antioxidant enzymes, proteins, and other molecules), antioxidants can also capture and stabilize free radicals, such as ascorbic acid, vitamin E, various polyphenols, and other exogenous small molecules [6], thus protecting the cells from free radical damage. As a traditional Chinese drink, this tea appears to be rich in tea polyphenols and can provide antioxidants to alleviate the damage caused by free radicals [7].  
Prevention of chromosomal aberration and gene mutation is important for preventing tumorigenesis [8]. Environmental pollution is a principal mutagen in the pathogenesis of tumors, though it is difficult to eliminate the causes of such contamination [9]. As an important segment of natural products, tea extracts are available in a wide range of types and present a broad range of efficacies and research values [10], especially in regard to anti-mutagen activities.  
Hepatocellular carcinoma (HCC) is a common malignant disease with a high morbidity and mortality around the world, and the morbidity and mortality of HCC in China account for about half of that occurring throughout the world [11]. At present, there is no effective treatment for liver cancer, and its mortality rate can only be reduced by early detection, diagnosis, and treatment. The bioactive components in traditional Chinese medicine and some foods have been shown to prevent and treat different types of cancer by improving the body's immunity. For example, drinking tea can benefit liver cancer patients in regard to surgery, chemotherapy, and radiotherapy outcomes [12].  
In this context, WST extracts were used as a raw material to explore their effects regarding anti-oxidant and anti-mutagenic activities. Additionally, in vitro anti-cancer experiments on human hepatoma HepG2 cells utilizing these extracts were assessed, and their potential bioactive compounds were investigated via HPLC.