## 3 Results
### Untargeted Metabolomics Analysis
#### 3.3.2 Differential Metabolite Screening  
To identify the metabolites responsible for clustering and class differences among different _S. grosvenorii_ groups, the three groups were screened for differential metabolites using criteria of VIP \(\geq\) 1 and \(p\) < 0.05. This screening identified a total of 470 differential metabolites, as shown in Table 4. The primary metabolites identified were carboxylic acids and their derivatives, with fatty acyls, organooxygen compounds, and benzene derivatives following in abundance. In our study, we observed significant differences in metabolite content between various groups of _S. grosvenorii_ (Figure 2). Specifically, when comparing fresh _S. grosvenorii_ from Yongfu with that from Longsheng, we identified 193 differential metabolites. Of these, 86 were down-regulated and 107 were up-regulated. Further, when comparing fresh and dried _S. grosvenorii_ from Yongfu, 234 differential metabolites were identified, with 93 being down-regulated and 141 being up-regulated. Notably, 131 of these differential metabolites were common across the comparisons between the Yongfu and Longsheng fresh samples as well as between the fresh and dried samples from Yongfu. These findings are illustrated in the heatmap. In comparing the fresh Yongfu and Longsheng varieties of _S. grosvenorii_ (Figure 3A), significant differences were observed in 31 carboxylic acids and their derivatives, most of which were amino acids, comprising 97% of the content. Among these, 13 metabolites, including proline, beta-leucine, phenylalanine, and N6-acetyl-L-lysine, were up-regulated, while 19 others were down-regulated. Fatty acyls, which play a critical role in energy production and maintaining cell membrane integrity [24] showed differences in 20 metabolites. Of these, 11 metabolites, such as pantothenol and methyl jasmonate, were up-regulated, while 9, including L-2-hydroxyglutaric acid and 9-OxoODE, were down-regulated. Further analysis revealed differences in 16 organooxygen compounds, predominantly carbohydrates. In this category, 11 metabolites, such as cellopentaose and trehalose, were up-regulated, whereas 5 metabolites, including arabinose and muramic acid, were down-regulated. Benzene and its derivatives, known for their roles in growth regulation and anti-inflammatory effects, also showed significant variation. A \begin{table}
\begin{tabular}{c c} \hline \hline
**Metabolite Class** & **Percentage (\%)** \\ \hline Carboxylic acids and derivatives & 15.31 \\ Fatty acyls & 9.8 \\ Organooxygen compounds & 9.3 \\ Benzene and substituted derivatives & 7.6 \\ Prench lipids & 4.0 \\ Organointrogen compounds & 2.5 \\ Phenols & 2.5 \\ Indoles and derivatives & 2.1 \\ others & 45 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Metabolite distribution of _S. grosvenorii_ in different groups. Figure 2: Differential metabolites statistics histogram (VIP \(\geq\) 1 and \(p\) < 0.05). total of 16 such compounds were detected, with 12, including 2-hydroxybenzaldehyde and 4-hydroxyphenylacetaldehyde, being up-regulated, while 4, such as phenylacetic acid and _p_-aminobenz acid, were down-regulated. Additionally, among the five prenol lipids identified, two were up-regulated and three were down-regulated, highlighting the nuanced metabolic differences between the two varieties of _S. grosvenorii_. In the comparison between the fresh and dried Yongfu varieties of _S. grosvenorii_ (Figure 3B), we identified 40 carboxylic acids, and their derivatives were significantly different. Of these, 21 differential metabolites were up-regulated, including proline, beta-leucine, gamma-aminobutyric acid, and N6-acetyl-L-lysine. Conversely, 19 differential metabolites, such as limonoate, were down-regulated. In the category of fatty acids, 21 metabolites were identified. Among them, 14, including kojibiose, were up-regulated, while 7, such as 5-acetamidovalerate and dodecanoic acid, were down-regulated.