Medicinal Plant Research 2024, Vol.14, No.1, 31-44 http://hortherbpublisher.com/index.php/mpr 36 short-chain fatty acids, which are crucial for gut health (Zhang et al., 2019). Additionally, compounds such as chrysoeriol glucosides and alternanthin have demonstrated neuroprotective and antioxidant activities, which contribute to the plant's therapeutic potential (Shan et al., 2020). The chemical composition varies significantly among different varieties of yam, with the peel of Huai yam containing predominantly phenolic compounds that promote α-glucosidase activity, while other compounds exhibit enzyme inhibitory effects, indicating the regulatory role of various small molecules in blood glucose levels (https://mall.cnki.net/magazine/article/CDMD/1022690095.htm). Wencheng yam polysaccharides consist of glucose, mannose, and galactose in a molar ratio of 36.5:1.63:1. These polysaccharides may adopt a helical conformation with a granular surface, demonstrating notable in vitro antioxidant and blood glucose-lowering activities that correlate positively with concentration (https://wap.cnki.net/touch/web/Dissertation/Article/1022778900.nh.html). The antioxidant activity of Wencheng yam polysaccharides primarily involves scavenging free radicals, activating antioxidant enzymes, regulating the expression of the anti-aging gene klotho, and modulating the p53/p12 signaling pathway to exert anti-aging effects. Furthermore, they enhance their in vitro antioxidant activity by scavenging hydroxyl radicals, superoxide anions, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals (Sun et al., 2019). The chemical composition of Dioscorea nipponica is relatively simple, primarily consisting of steroidal saponin compounds. Dioscorea nipponica has become an important starting material for the synthesis of synthetic contraceptives and steroid hormone drugs. Hormonal products such as progesterone, oxytocin, and cortisone acetate synthesized based on it have been widely used clinically, making it the second largest category of drugs in the international pharmaceutical market after antibiotics. Currently, diosgenin is widely used as a raw material for steroid hormone drugs, especially corticosteroids and contraceptive steroids, in countries worldwide. In addition to being a critical raw material for synthesizing hormone drugs, diosgenin also exhibits various biological activities such as anti-tumor, anti-inflammatory, lipid-lowering, and anti-aging effects on the skin. The biosynthesis of these bioactive compounds involves complex metabolic pathways. For instance, the production of steroidal saponins like diosgenin, a precursor to many pharmacologically active compounds, is a multi-step process involving the conversion of cholesterol through site-specific oxidation and glycosylation (Ge et al., 2023). Transcriptomic studies have identified key enzymes, such as cytochrome P450s (CYPs) and UDP-glycosyltransferases (UGTs), that play crucial roles in these biosynthetic pathways (Wang et al., 2020; Ge et al., 2023). 4.3 Genomic insights into medicinal compound production Recent genomic and transcriptomic analyses have provided deeper insights into the biosynthesis of medicinal compounds in yam. High-throughput sequencing of leaf and rhizome tissues has revealed a wealth of genetic information, including differentially expressed genes (DEGs) that are involved in the synthesis of terpenoids and other bioactive metabolites (Li et al., 2020). These studies have identified numerous candidate genes that are potentially involved in the biosynthesis of key medicinal compounds, thereby providing references for future functional investigations (Li et al., 2020). With the development of genomics and functional genomics, significant advances have been made in exploring cholesterol pathways in plants, such as the discovery of steroidal saponin synthesis pathways and the identification of downstream synthetic genes. The value of genomics is increasingly highlighted as it combines with functional genomics and even metabolomics, greatly promoting the elucidation of important secondary metabolite synthesis pathways in plants. The application of high-throughput sequencing technologies plays a crucial role in medicinal plant research, particularly in deeply exploring genes related to the biosynthesis of secondary metabolites. Understanding these genes, their characteristics, and predicting their functions contribute to further biochemical studies on medicinal component biosynthesis pathways. This enhances our understanding of the biosynthesis or regulatory networks of medicinal components, thereby promoting biotechnological methods to increase their yield to meet medicinal demands. However, genetic information on medicinal plants, especially non-model species, is relatively limited. Medicinal plant genomes are often complex, with high heterozygosity,
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