Koyama Ryohei, Ishibashi Misaki, Fukuda Itsuko, Okino Akitoshi, Osawa Ro, Uno Yuichi
Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe 657-8501, Japan.
Department of Agrobioscience, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe 657-8501, Japan.
Plants (Basel). 2022 Aug 27;11(17):2220. doi: 10.3390/plants11172220.
The strawberry fruit contains abundant polyphenols, such as anthocyanins, flavan-3-ol, and ellagitannin. Polyphenol enrichment improves the quality of strawberries and leads to a better understanding of the polyphenol induction process. We measured the total polyphenol content of strawberry fruits under different growth conditions, developmental stages, and treatment conditions during pre-harvest and post-harvest periods. High fruit polyphenol content was observed in cold treatment, which was selected for further analysis and optimization. A transcriptome analysis of cold-treated fruits suggested that the candidate components of polyphenols may exist in the phenylpropanoid pathway. Coverage with a porous film bag excluded the effects of drought stress and produced polyphenol-rich strawberry fruits without affecting quality or quantity. The degree of stress was assessed using known stress indicators. A rapid accumulation of abscisic acid was followed by an increase in superoxide dismutase and DPPH (2,2-Diphenyl-1-picrylhydrazyl) activity, suggesting that the strawberry fruits responded to cold stress immediately, reaching the climax at around 6 days, a trend consistent with that of polyphenol content. These findings enhance our understanding of the mechanism of post-harvest polyphenol accumulation and the value of strawberries as a functional food.
草莓果实含有丰富的多酚类物质，如花色苷、黄烷 -3-醇和鞣花单宁。多酚富集可提高草莓品质，并有助于更好地理解多酚诱导过程。我们测定了采前和采后不同生长条件、发育阶段及处理条件下草莓果实的总多酚含量。在冷藏处理中观察到果实多酚含量较高，因此选择冷藏处理进行进一步分析和优化。对冷藏处理果实的转录组分析表明，多酚的候选成分可能存在于苯丙烷途径中。用多孔薄膜袋覆盖排除了干旱胁迫的影响，生产出富含多酚的草莓果实，且不影响果实的品质和产量。使用已知的胁迫指标评估胁迫程度。脱落酸迅速积累，随后超氧化物歧化酶和DPPH（2,2-二苯基-1-苦基肼）活性增加，这表明草莓果实对冷胁迫立即做出反应，在大约6天时达到高峰，这一趋势与多酚含量一致。这些发现增进了我们对采后多酚积累机制以及草莓作为功能性食品价值的理解。
