Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315832, China.
Key Laboratory of Animal Protein Food Processing Technology of Zhejiang Province, College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo 315832, China; State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo, Zhejiang 315211, China.
Food Res Int. 2021 Feb;140:109984. doi: 10.1016/j.foodres.2020.109984. Epub 2020 Dec 24.
High hydrostatic pressure (HHP) technique is used as a novel abiotic stress factor for efficiently enhancing the biosynthesis of selected bioactive phytochemicals in germinated wholegrain, but the information about HHP stress-induced metabolic changes remains rather limited. Thus, the current work employed an untargeted gas chromatography-mass spectrometry-based metabolomic approach combining with multivariate models to analyze the effect of mild HHP stress (30 MPa/5 min) on the overall metabolome shifts of wholegrain brown rice (WBR) during germination. Simultaneously, major phenolics in germinated WBR (GBR) were detected by ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry, to explore the potential relationship between HHP stress-induced rice metabolome alternations and the biotransformation of bioactive components. The results demonstrated that the influence of HHP stress on GBR metabolite profiles was defined by germination durations, as revealed by the differentiation of the stressed grains from the naturally germinated grains at different germination points according to principal component analysis. This was further confirmed by the results of orthogonal projections to latent structures discriminant analysis, in which the discriminating metabolites between naturally germinated and HHP-stressed grains varied across the germination process. The metabolite signatures differentiating natural and HHP-stressed germination included glycerol-3-phosphate, monosaccharides, gamma-aminobutyric acid, 2,3-butanediol, glyceryl-glycoside, amino acids and myo-inositol. Besides, HHP stress led to the increase in ribose, arabinitol, salicylic acid, azelaic acid and gamma-aminobutyric acid, as well as the reduced phenolic acids. These results demonstrated that HHP stress before germination matched with appropriate process parameters could be used as a promising technology to tailor metabolic features of germinated products, thus exerting targeted nutrition and health implications.
高静压（HHP）技术被用作一种新的非生物胁迫因素，可有效地提高发芽全谷物中选定生物活性植物化学物质的生物合成，但关于 HHP 胁迫诱导的代谢变化的信息仍然相当有限。因此，本研究采用非靶向气相色谱-质谱联用代谢组学方法结合多元模型，分析了温和 HHP 胁迫（30 MPa/5 min）对发芽糙米（WBR）整个代谢组在发芽过程中的整体代谢组变化的影响。同时，通过超高效液相色谱/四极杆飞行时间质谱法检测发芽糙米（GBR）中的主要酚类物质，以探讨 HHP 胁迫诱导的水稻代谢组变化与生物活性成分的生物转化之间的潜在关系。结果表明，HHP 胁迫对 GBR 代谢物谱的影响取决于发芽时间，根据主成分分析，不同发芽点的胁迫谷物与自然发芽谷物之间存在差异，从而定义了 HHP 胁迫对 GBR 代谢物谱的影响。正交投影到潜在结构判别分析的结果进一步证实了这一点，其中区分自然发芽和 HHP 胁迫谷物的判别代谢物在整个发芽过程中发生了变化。区分自然和 HHP 胁迫发芽的代谢物特征包括甘油-3-磷酸、单糖、γ-氨基丁酸、2,3-丁二醇、甘油糖苷、氨基酸和肌醇。此外，HHP 胁迫导致核糖、阿拉伯糖醇、水杨酸、壬二酸和γ-氨基丁酸增加，而酚酸减少。这些结果表明，发芽前的 HHP 胁迫与适当的工艺参数相匹配，可以用作定制发芽产品代谢特征的有前途的技术，从而发挥有针对性的营养和健康意义。
