Abstract This paper reports the discrimination of Acacia gums from the two most widely used and commercially significant species, A. senegal and A. seyal, using an innovative strategy based on matrix assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) after enzymatic digestion of the polysaccharide component. MALDI-TOF MS/MS experiments were carried out to determine the composition of the most intense ions of A. seyal gum and elucidate its mass fingerprint. The analytical method was applied to the analysis of gums from 12 other Acacia species and an attempt was made to find specific oligosaccharides that could be used to discriminate among them. Statistical analysis was performed to further explore the capability to differentiate these species. The implementation of a library of MALDI mass profiles of plant gums, with an initial focus on Acacia gums, represents the first MS-based attempt to facilitate reliable, species-level identification of these materials in unknown samples. The technique was successfully applied to the analysis of micro-samples from art objects of different types, with regard to geographical origin and date, including artefacts from ancient Egypt and a 20th century painting by Georges Braque, in the collections of The Metropolitan Museum of Art, New York, and the Art Institute of Chicago. Results demonstrated the possibility to detect Acacia gums from different species even in complex and aged micro-samples, providing important insights into the materials and condition of the objects. This research shows the potential to open new avenues of art historical and technical investigation into the specific plant sources, trade, and selection of materials by artists.

中文翻译：

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MALDI-TOF MS 鉴别金合欢树胶：对艺术品微量样品的应用

摘要 本文报道了使用基于基质辅助激光解吸电离飞行时间质谱 (MALDI- TOF MS) 酶消化多糖成分后。进行 MALDI-TOF MS/MS 实验以确定 A. seyal 树胶中最强离子的组成并阐明其质量指纹。将该分析方法应用于其他 12 种金合欢树胶的分析，并试图找到可用于区分它们的特定寡糖。进行统计分析以进一步探索区分这些物种的能力。实施植物胶的 MALDI 质量谱库，最初专注于金合欢树胶，代表了首次基于 MS 的尝试，以促进对未知样品中这些材料的可靠、物种级鉴定。该技术已成功应用于分析不同类型艺术品的微样本，涉及地理来源和日期，包括来自大都会艺术博物馆收藏的古埃及文物和乔治·布拉克 (Georges Braque) 20 世纪的画作、纽约和芝加哥艺术学院。结果表明，即使在复杂和老化的微型样品中，也可以检测来自不同物种的金合欢树胶，为了解物体的材料和状况提供了重要的见解。这项研究显示了为特定植物来源、贸易、