Multimodal mass spectrometry imaging to study aged cognac barrels

质谱成像（MSI）是基于在表面上定期记录质谱，然后可以用来重建离子密度图，称为质谱图。有几种方法可以从表面产生离子，其中有两种特别流行，即飞行时间二次离子质谱法（TOF-SIMS）和基质辅助激光解吸电离法（MALDI）。首先，它可以在小于一微米的空间分辨率下记录有机和无机离子的图像，并且还可以进行深度剖面分析。第二个允许访问更大的生物分子，如果与傅里叶变换质谱仪相结合，在几微米的空间分辨率下提供出色的质量分辨率（rbbb10万）和质量精度（1-2 ppm）。这两种方法具有很强的互补性，并将进一步发展到一个新的应用领域，即文化遗产研究。这将以不同木材制成的干邑桶为例，这些桶来自不同的合作社，历史长达150年。离子图像将用新的算法分析输运和扩散过程。代谢物的鉴定将基于萃取物的LC-MSMS数据，并通过先进的代谢物网络算法（“分子网络”）进行分析。在第一部分中，木材（棒材）通过与一边的馏分液和另一边的大气接触而产生的时间变化将被研究。酒杆的成分通过酒精的蒸发而改变——即所谓的天使份额。通过对木棒横截面的分析，可以更好地了解传统方法的非物质文化遗产以及木桶老化对产品质量的影响。该项目的第二部分重点是木桶与真菌Baudoinia compniacensis的相互作用。这种真菌会导致酒窖内外的墙壁变黑，但不会直接生长在木桶上。因此，我们将研究橡树木材的哪些成分是减少真菌生长的原因。更好地了解木耳相互作用的分子过程可以形成环境友好策略的基础，以减少这种（另一种）真菌物种。

Mass spectrometry imaging (MSI) is based on recording mass spectra at regular intervals on a surface, which can then be used to reconstruct ion density maps that are called mass spectrometry images. Several methods exist to produce ions from the surface, and among them two are particularly popular, time-of-flight secondary ion mass spectrometry (TOF-SIMS), and matrix assisted laser desorption-ionization (MALDI). The first makes it possible to record images of organic and inorganic ions at a spatial resolution of less than one micron, and also allows depth profile analyzes. The second allows access to larger biomolecules and, if coupled with Fourier transform mass spectrometers, provides excellent mass resolution (R > 100,000) and mass accuracy (1-2 ppm) at a spatial resolution of a few microns. These two methods are highly complementary and will be developed further for a new application area, namely cultural heritage studies. This will be exemplified on cognac barrels made from different wood and originating from different cooperages with an age of up to 150 years. Ion images will be analyzed by new algorithms for the analysis of transport and diffusion processes. The identification of metabolites will be based on LC-MSMS data of extracts which is analyzed by advanced metabolite network algorithms (‘molecular networks’). In the first part temporal changes of wood (staves) by contact to the distillate on the one side and the atmosphere on the other side will be investigated. The composition of the staves is changed by the evaporation of alcohol - the so-called Angel’s share. The analysis of cross sections of staves will lead to a better understanding of immaterial cultural heritage of traditional methods and the influence of wood barrel aging on product quality. The second part of this project is focused on the interaction of wood barrels with the fungus Baudoinia compniacensis. This fungus causes the blackening of outside and inside cellar walls, but never grows directly on the wood barrels. Therefore, we will investigate which components of the oak wood are responsible for the reduction of fungus growth. A better understanding of the molecular processes of wood fungus interaction can form the basis for environmentally friendly strategies to reduce this (an other) fungus species.