Padilla-González Guillermo F, Grosskopf Esther, Sadgrove Nicholas J, Simmonds Monique S J
Royal Botanic Gardens, Kew, Richmond Surrey, London TW9 3AB, UK.
Plants (Basel). 2022 Mar 18;11(6):809. doi: 10.3390/plants11060809.
Grape seeds are a rich source of flavan-3-ol monomers, oligomers, and polymers. The diverse profile of compounds includes mainly B-type procyanidins (especially C4→C8 linked molecules) and the key monomers, catechin, and epicatechin that are positively implicated in the 'French Paradox'. Today grape seed nutraceuticals have become a multi-million-dollar industry. This has created incentives to elucidate the variations in chemistry across cultivars, to identify signs of adulteration, and to understand the intrinsic and extrinsic factors controlling the expression of metabolites in the seeds' metabolome. This review provides a critical overview of the existing literature on grape seed chemistry. Although the biosynthetic pathways for polymeric procyanidins in seeds have not yet been explained, abiotic factors have been shown to modulate associated genes. Research of extrinsic factors has demonstrated that the control of procyanidin expression is strongly influenced, in order of importance, by genotype (species first, then variety) and environment, as claimed anecdotally. Unfortunately, research outcomes on the effects of abiotic factors have low certainty, because effects can be specific to genotype or variety, and there is limited control over physical metrics in the field. Thus, to gain a fuller understanding of the effects of abiotic factors and biosynthetic pathways, and realise potential for optimisation, a more fundamental research approach is needed. Nevertheless, the current synthesis offers insight into the selection of species or varieties according to the profile of polyphenols, as well as for optimisation of horticultural practices, with a view to produce products that contain the compounds that support health claims.
葡萄籽是黄烷-3-醇单体、低聚物和聚合物的丰富来源。化合物的多样谱主要包括B型原花青素（特别是C4→C8连接的分子）以及关键单体儿茶素和表儿茶素，它们与“法国悖论”呈正相关。如今，葡萄籽营养保健品已成为一个价值数百万美元的产业。这促使人们去阐明不同品种间的化学差异，识别掺假迹象，并了解控制种子代谢组中代谢物表达的内在和外在因素。本综述对现有关于葡萄籽化学的文献进行了批判性概述。尽管种子中聚合原花青素的生物合成途径尚未得到解释，但非生物因素已被证明可调节相关基因。对外在因素的研究表明，正如坊间所说，原花青素表达的控制受到基因型（首先是物种，然后是品种）和环境的强烈影响，且影响程度依次递减。不幸的是，关于非生物因素影响的研究结果确定性较低，因为这些影响可能因基因型或品种而异，而且在田间对物理指标的控制有限。因此，为了更全面地了解非生物因素和生物合成途径的影响，并实现优化的潜力，需要一种更基础的研究方法。尽管如此，当前的综述为根据多酚谱选择物种或品种以及优化园艺实践提供了见解，以期生产出含有支持健康宣称的化合物的产品。
