REQUIMTE/Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal.
Food Chem. 2013 Dec 15;141(4):3636-48. doi: 10.1016/j.foodchem.2013.06.045. Epub 2013 Jun 20.
Soybean (Glycine max (L.) Merrill) is one of the most important food crops for human and animal consumption, providing oil and protein at relatively low cost. The least expensive source of nitrogen for soybean is the biological fixation of atmospheric nitrogen by the symbiotic association with soil bacteria, belonging mainly to the genus Bradyrhizobium. This study was conducted to assess the effect of the inoculation of G. max with Bradyrhizobium japonicum on the metabolite profile and antioxidant potential of its seeds. Phenolic compounds, sterols, triterpenes, organic acids, fatty acids and volatiles profiles were characterised by different chromatographic techniques. The antioxidant activity was evaluated against DPPH, superoxide and nitric oxide radicals. Inoculation with B. japonicum induced changes in the profiles of primary and secondary metabolites of G. max seeds, without affecting their antioxidant capacity. The increase of organic and fatty acids and volatiles suggest a positive effect of the inoculation process. These findings indicate that the inoculation with nodulating B. japonicum is a beneficial agricultural practice, increasing the content of bioactive metabolites in G. max seeds owing to the establishment of symbiosis between plant and microorganism, with direct effects on seed quality.
大豆（Glycine max (L.) Merrill）是人类和动物食用的最重要的粮食作物之一，它以相对较低的成本提供油和蛋白质。大豆最便宜的氮源是通过与土壤细菌共生固氮，主要属于慢生根瘤菌属（Bradyrhizobium）。本研究旨在评估接种大豆根瘤菌（Bradyrhizobium japonicum）对大豆种子代谢物谱和抗氧化潜力的影响。采用不同的色谱技术对酚类化合物、甾醇、三萜、有机酸、脂肪酸和挥发性物质进行了特征描述。采用 DPPH、超氧自由基和一氧化氮自由基评估抗氧化活性。接种 B. japonicum 诱导了 G. max 种子中初级和次级代谢物谱的变化，但不影响其抗氧化能力。有机和脂肪酸以及挥发物的增加表明接种过程具有积极作用。这些发现表明，接种结瘤的 B. japonicum 是一种有益的农业实践，通过植物和微生物之间的共生关系增加了 G. max 种子中生物活性代谢物的含量，直接影响种子质量。
