Wang Hung Li, Hopfer Helene, Cockburn Darrell W, Wee Josephine
Department of Food Science, The Pennsylvania State University, University Park, PA, United States.
Sensory Evaluation Center, The Pennsylvania State University, State College, PA, United States.
Front Microbiol. 2021 Jan 11;11:614278. doi: 10.3389/fmicb.2020.614278. eCollection 2020.
Microbial diversity present on grapes in wineries, and throughout fermentation has been associated with important metabolites for final wine quality. Although microbiome-metabolome associations have been well characterized and could be used as indicators of wine quality, the impact of regionality on the microbiome and metabolome is not well known. Additionally, studies between microbiome and metabolome have been conducted on single species grape such as instead of other species and interspecific hybrids. Although the Pennsylvania wine industry is relatively young compared to California, the industry has been experiencing rapid growth over the past decade and is expected to continue to grow in the future. Pennsylvania's climate of cold winters and high levels of rainfall throughout the growing season favors cultivation of interspecific hybrid grapes such as Chambourcin, one of the most commonly grown hybrid varieties in the state. Chambourcin is a prime candidate for studying the impact of regionality on microbiome-metabolome interactions as interspecific hybrid varieties could shape the future of winemaking. Here, we identify for the first time the regional distribution of microbial communities and their interactions with volatile metabolome during fermentation (0-20 days) by integrating high throughput Illumina sequencing (16S and ITS) and headspace-solid phase microextraction-gas chromatography-mass spectrometry. Analyzing 88 samples from nine wineries in the Central and East Pennsylvania regions, we observed high microbial diversity during early stages of fermentation (1-4 days) where non- yeasts such as and and non- bacteria, , likely contribute to microbial to the resulting wines. Furthermore, key differentiators between two regions in Pennsylvania, as identified by LEfSe analysis, include the fungal genera and and the bacterial genera and . Moreover, 29 volatile fermentation metabolites were discriminated significantly (variable importance in projection > 1) between the two regions as shown by Partial Least Squares-Discriminant Analysis. Finally, Spearman's correlation identified regional differences of microbial-metabolite associations throughout fermentation that could be used for targeted microbiome manipulation to improve wine quality and preserve regionality. In summary, these results demonstrate the microbial signatures during fermentation and differential microorganisms and metabolites further support impact of regionality on Chambourcin wines in Pennsylvania.
酒庄葡萄上以及整个发酵过程中存在的微生物多样性与影响葡萄酒最终品质的重要代谢产物相关。尽管微生物组与代谢组之间的关联已得到充分表征，并且可作为葡萄酒品质的指标，但地域对微生物组和代谢组的影响尚不清楚。此外，微生物组与代谢组之间的研究多针对单一品种葡萄，如 ，而非其他品种和种间杂交品种。尽管与加利福尼亚相比，宾夕法尼亚州的葡萄酒产业相对年轻，但在过去十年中该产业一直在快速发展，预计未来还将继续增长。宾夕法尼亚州冬季寒冷且生长季节降雨量大的气候条件有利于种植种间杂交葡萄，如香宝馨（Chambourcin），它是该州最常见的杂交品种之一。香宝馨是研究地域对微生物组 - 代谢组相互作用影响的理想候选品种，因为种间杂交品种可能会塑造葡萄酒酿造的未来。在此，我们通过整合高通量Illumina测序（16S和ITS）以及顶空 - 固相微萃取 - 气相色谱 - 质谱，首次确定了发酵过程（0 - 20天）中微生物群落的区域分布及其与挥发性代谢组的相互作用。分析宾夕法尼亚州中部和东部地区九个酒庄的88个样本，我们观察到发酵早期（1 - 4天）微生物多样性较高，其中非酵母类如 和 以及非细菌类 可能对所酿葡萄酒的微生物 有贡献。此外，通过LEfSe分析确定的宾夕法尼亚州两个地区之间的关键差异因素包括真菌属 和 以及细菌属 和 。而且，偏最小二乘判别分析表明，两个地区之间有29种挥发性发酵代谢产物存在显著差异（投影变量重要性> 1）。最后，Spearman相关性确定了整个发酵过程中微生物 - 代谢产物关联的区域差异，这些差异可用于有针对性地操控微生物组，以提高葡萄酒品质并保留地域特色。总之，这些结果证明了发酵过程中的微生物特征以及不同的微生物和代谢产物，进一步支持了地域对宾夕法尼亚州香宝馨葡萄酒的影响。
