Open Access

ARTICLE

Integrated GC-MS and LC-MS-Based Untargeted Metabolomics Reveals Diverse Metabolites in Fermented Pine Needles

Yinyu Xu¹, Zheng Li¹, Qian Wen², Hao He¹, Pengtu Shi¹, Wenhua Zhou^2,*
1 Hunan Provincial Institute of Product and Goods Quality Inspection, Changsha, 410004, China
2 College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, China
* Corresponding Author: Wenhua Zhou. Email:

Phyton-International Journal of Experimental Botany https://doi.org/10.32604/phyton.2024.047949

Received 23 November 2023; Accepted 20 February 2024; Published online 19 September 2024

Abstract

The diversity of metabolites produced in fermented pine needles at different stages of fermentation has rarely been investigated. In the present study, untargeted metabolomic analysis using GC-MS and LC-MS was performed to detect metabolites in fermented pine needles at different fermentation stages. A total of 30 samples of pine needles fermented first with yeast (Saccharomyces cerevisiae) and then with a mixed bacterial culture of Lactobacillus fermentum CECT5716 and Bifidobacterium Breve M16V, were used to detect differential metabolites at different stages of fermentation. Pearson’s correlation analysis was used to determine correlations between metabolites and key microbial communities. A total of 708 differential metabolites (430 from LC-MS and 278 from GC-MS analysis) were identified. The PCA and OPLS-DA revealed distinct differences between metabolites at different fermentation stages. Key differential metabolites identified through GC-MS analysis included; Phosphoric acid, D-Fructose, 2-O-alpha-mannosyl-D-glycerate, 1,3-dihydroxyacetone dimer, Galactosylglycerol, 2-Isopropylmalic acid, alpha-D-Galactose, Citrate, 4-Hydroxycinnamic acid, and Shikimate. Similarly, key differential metabolites identified through LC-MS included; 2-Phenlyethanol, Dimethlglycine, 2-Hydroxybenzaldehyde, 3-Aminoisobutanoic acid, p-Cresol, Triethylamine, 2-Ketobutyric acid, Cytosine, Benzaldehyde, and Creatinine. Annotation of differential metabolites to KEGG pathway enrichment analysis revealed the association of these metabolites with phenylpropanoid, flavonoid, and secondary metabolite biosynthesis. Furthermore, the results showed that three bacterial (Firmicutes, Actinobacteria, and Lactobacillus) and three fungal genera (Penicillium, Candida, and Basidiomycota) significantly correlated with differential metabolites showing synergistic effects. Our study reveals a comprehensive comparison of metabolites at different fermentation stages and provides practical insights into the mechanism of metabolite enrichment in fermented pine needles.

---

Keywords

Fermented pine needle; Pinus massoniana; GC-MS; LC-MS; metabolomics

---