基于高通量测序技术比较不同品种龙眼干化学特征与菌群组成变化

Correlation Analysis Between the Chemical Characteristics and Bacterial Flora of Different Dried Longan by High-throughput Sequencing

摘要:

该研究以4种龙眼干为材料，用高通量测序技术构建了龙眼干中微生物菌群的基因组文库，分析果肉组织微生物在各水平上的群落结构及丰度信息，评估微生物群落多样性，分析龙眼干样品微生物菌群与其特征化学指标相关性。结果发现，4个品种龙眼干果胶含量范围为7.21mg/g ~10.62mg/g，凤梨穗龙眼干维生素C含量和总糖含量最高，分别为4.25 mg/100g、116.89mg/g。储良龙眼干可滴定酸含量为0.061%，泰国和凤梨穗龙眼干的可滴定酸含量相近。微生物菌群多样性分析指出，菌群组成与相对丰度在不同品种中存在差异，如变形菌门在泰国和凤梨穗龙眼干上含量较高，分别占65.35%和64.89%，而厚壁菌门在木眼（51.36%）和储良龙眼干（46.78%）上相对含量更高。相关性分析指出，龙眼干的含水量、维生素C和含糖量对微生物群落多样性影响较大，可滴定酸的作用相对较小。该实验为龙眼干的加工品种选择和储存提供了重要参考依据，为龙眼干产品的加工工艺与质量管理提供研究理论基础。

Abstract:

In this study, the genomic library of microflora in dried longan was constructed by high-throughput sequencing using tissues from four varieties of longan. The abundance of bacterial flora from these samples was analyzed at the phylum, order, family, and genus levels, and the diversity of microbial communities was evaluated by combining with the alpha diversity analysis. In addition, the correlation between the composition of microflora and characteristic chemical levels was compared. As the results, the pectin content of the four varieties of dried longan ranged from 7.21 mg/g to 10.62 mg/g. The highest content of vitamin C and total sugar were observed in Feng Li Sui longan variety, containing 4.25 mg/100g and 116.89 mg/g, respectively. And the highest titratable acid content was 0.061% in Chu Liang longan variety, while Thai and Feng Li Sui longan varieties' titratable acid content was similar. The diversity of microbial flora from four varieties of dried longan indicated that the differences in the composition and relative abundance of bacterial flora were observed in different varieties. For example, Proteobacteria were relatively high in Thai and Feng Li Sui longans, accounting for 65.35% and 64.89% respectively, while Firmicutes mainly accumulated in Mu Yan (51.36%) and Chu Liang (46.78%) longan samples. The correlation analysis showed that vitamin C and sugar content had greater effects on the diversity of microbial communities. In contrast, the level of titratable acid had a relatively minor effect on the diversity and number of bacteria in dried longan. This experiment provides an important reference basis for the selection of processing varieties and storage of dried longan, and provides a research basis for the processing and quality control of dried longan products.