Plant species of the Lycium genus belonging to the Solanaceae family are widely distributed in northern and northwestern China. Fruit from Lycium spp. is called goji berry or wolfberry. In China, eleven species and four varieties of goji in the wild have been recorded by the Flora of China (Chinese Academy of Sciences CHN, 2023). In addition to being commercially and ecologically valuable, goji is also used in traditional Chinese medicines (TCM) in East Asian countries. Studies have confirmed that a variety of goji, including Lycium barbarum Linn and Lycium chinense Mill have suitable pharmacological activities (Liang et al., 2019; Ma et al., 2020; Zheng et al., 2018).

The Pharmacopoeia of the People's Republic of China (ChP) stipulates that the mature dried fruit of L. barbarum is goji, and the root bark of L. barbarum and L. chinense is Lycii cortex (Committee, 2020). Goji has a long medicinal history in China, which can enhance essence and eyesight, nourish the liver and kidney, nourish the yin and moisten the lung, tonify deficiency and benefit the essence. After extensive research, both Chinese and international scholars have discovered that goji is rich in numerous medicinal components, including Lycium barbarum polysaccharide (LBP), alkaloids, polyphenols, carotenoids and amino acids (Qian et al., 2017b). As a result, goji has various pharmacological effects, such as antioxidant, blood sugar regulation, liver protection, immune regulation, anti-inflammatory, and neuroprotective properties (Wei et al., 2018). Studies have shown that the Lycii cortex has pharmacological properties, such as antibacterial and anti-inflammatory, immunomodulatory, antipyretic and analgesic properties, and can lower blood pressure, cholesterol levels and blood sugar levels (Chen et al., 2021).

The evaluation criteria of goji have focused on distinguishing the authenticity of medicinal materials while neglecting the determination of active ingredient levels. Thus, the goji quality has not been able to be scientifically evaluated. The Japanese Pharmacopoeia uses thin-layer chromatography (TLC) for the identification of goji, with the appearance of yellow spots at Rf approximately 0.6 under the measurement method as the standard (Hygiene, 2016). The European Pharmacopoeia also uses TLC, but rutin trihydrate and scopolamine lactone are the reference standards (Europe, 2020). In contrast, the Korean Pharmacopoeia uses betaine as a quality marker (Ministry, 2019). The quality evaluation of goji in China follows the ChP, mostly focusing on the detection of LBP and betaine. However, the polysaccharide detection methods only determine the total polysaccharide level, lacking key information such as monosaccharide composition and structure, which cannot fully explain quality differences in goji and poses the risk of adulteration. Betaine is commonly utilized due to its ease of determination. In recent years, the quality evaluation of TCM has been shifting toward a more holistic and multicomponent approach. Thus, the use of betaine as the sole quality evaluation marker lacks sufficient evidence to support its specificity (Wang et al., 2018b).

This article examines the quality evaluation methods of the main compounds in goji. We summarize the existing research status and pharmacological effects of the phenolamides in goji. Furthermore, we explore the feasibility of using phenolamides as quality evaluation markers, to advance the development of quality evaluation of goji. Our findings provide valuable insights into the potential of phenolamides as a quality evaluation marker for goji and contribute to ongoing efforts to improve the standardization and quality of TCM.