稻米营养成分的年份演变及其与品质性状的耦合代谢组学解析

Analysis of the annual evolution of nutritional components in Oryza sativa L. and coupled metabolomics with quality traits

中文关键词:  稻米  年代演变  代谢组学  营养成分  品质性状

英文关键词:Oryza sativa L.  year evolution  metabolomics  nutritional components  quality traits

中文摘要:

      目的 系统解析同一稻米品种在长期尺度上的营养品质与代谢特征演变规律。方法 以湖北省农业科学院长期保存的鄂中5号稻米材料, 选取2009、2019—2022 5个生产年份样品, 在品种一致、栽培管理相同、贮藏条件可追溯的前提下开展分析。通过常规理化方法测定蒸煮品质、黏度特性及主要营养成分, 并结合基于超高效液相色谱-串联质谱法的非靶向代谢组学对样品进行系统表征。结果 共鉴定273种代谢物。根据Classy Fire化学分类体系, 这些代谢物可划分为9个超类, 其中脂质和类脂质分子占比最高。不同年份稻米在直链淀粉、胶稠度、蛋白质和氨基酸等指标上存在阶段性差异; 主成分分析代谢谱结构具有明确的年份分布; 差异代谢物主要集中于脂肪酰类、甘油磷脂类、黄酮类及有机酸衍生物等类别, 提示脂质代谢与次生代谢在年份变化中贡献突出。基于代谢谱构建的机器学习模型判别性能良好, 三折交叉验证准确率达93.33%, 说明了不同年份稻米具有稳定可识别的代谢特征。结论 同一品种稻米在长期储存与年份演变过程中, 其品质性状与代谢组成呈现稳定且可识别的年份差异特征。本研究基于稀缺的跨十余年同品种样本, 揭示了稻米品质与代谢特征的年代演变规律, 为稻米品质评价及储藏管理研究提供了重要参考。

英文摘要:

      Objective To systematically characterize the long-term evolutionary patterns of nutritional quality and metabolic profiles in a single Oryza sativa L. cultivar. Methods Oryza sativa L. samples of the cultivar Ezhong No.5, preserved by the Hubei Academy of Agricultural Sciences, encompassing 5 production years (2009 and 2019–2022), were analyzed. Under conditions of identical cultivar background, consistent cultivation management, and traceable storage conditions, cooking quality, intrinsic viscosity and major nutritional components were determined using conventional physicochemical methods, while comprehensive metabolic characterization was conducted through untargeted metabolomics based on ultra performance liquid chromatography-tandem mass spectrometry. Results A total of 273 metabolites were identified. According to the Classy Fire chemical classification system, these metabolites could be divided into 9 superclasses, with lipids and lipid-like molecules accounting for the largest proportion. Oryza sativa L. samples from different production years exhibited stage-dependent variations in amylose, gel consistency, protein and amino acids. Principal component analysis demonstrated a distinct year-dependent separation of metabolic profiles. Differential metabolites were primarily enriched in fatty acyls, glycerophospholipids, flavonoids and organic acid derivatives, indicating that lipid metabolism and secondary metabolic pathways contributed substantially to year-related metabolic variations. A gradient boosting machine model established based on metabolomic profiles exhibited favorable discriminative performance, achieving an accuracy of 93.33% in three-fold cross-validation, thereby demonstrating the presence of stable and distinguishable metabolic signatures among Oryza sativa L. samples from different production years. Conclusion During long-term storage and chronological progression, the quality traits and metabolic composition of the same Oryza sativa L. variety exhibit stable and identifiable differences over time. This study, based on a scarce sample of the same variety spanning more than ten years, reveals the chronological evolution of Oryza sativa L. quality and metabolic characteristics, providing an important reference for Oryza sativa L. quality evaluation and storage management research.