TY - JOUR A1 - Vermeeren, Sarah A1 - Witzler, Markus A1 - Makarow, Ramona A1 - Engelhard, Carsten A1 - Kaul, Peter T1 - Multivariate evaluation method for the detection of pest infestations on plants via VOC analysis using gas chromatography mass spectrometry N2 - Volatile organic compounds (VOCs) play an important role in the defense against pest infestations on plants. The analysis of these VOCs using gas chromatography mass spectrometry (GC-MS) enables the detection of pests by analyzing the VOC composition (VOC profiles) for specific patterns and markers. The analysis of such complex datasets with high biovariability poses a particular challenge. For this reason, a multivariate evaluation method based on a self-written Python script, using principal component analysis (PCA) and linear discriminant analysis (LDA), was developed and tested for functionality using a dataset, which has been evaluated manually and has identified five specific markers (2,4-dimethyl-1-heptene, 3-carene, alpha-longipinene, cyclosativene, and copaene) for Anoplophora glabripennis (ALB) infestation on Acer trees. The results obtained in the present study did not only match the manually evaluated results, but lead to further insight into the dataset. Another sesquiterpene which is assumed to be alpha-zingiberene was identified as an ALB specific marker in addition to 2,4-dimethyl-1-heptene and 3-carene. Furthermore, the European native beetle species goat moth Cossus cossus (CC) and poplar long-horned beetle Saperda carcharias (SC) were also analyzed for their VOCs to differentiate ALB specific VOC from other pest infestations. This comparison lead to the conclusion that the compounds alpha-longipinene, cyclosativene, and copaene are not specific for ALB but for pest infestation in general. It was possible to identify not only specifically produced VOCs, but also differences in concentrations that arise specifically during ALB infestation. Therefore, the evaluation method for the detection of plant pests presented in this study represents a time-saving alternative to conventional non computing methods, which in addition provides more detailed results. KW - Mass Spectrometry KW - Gas Chromatography KW - Volatile organic compounds KW - Pest infestation PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639526 DO - https://doi.org/10.1038/s41598-025-11607-5 SN - 2045-2322 VL - 15 IS - 1 SP - 1 EP - 10 PB - Springer Science and Business Media LLC AN - OPUS4-63952 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Braun, Jennifer A1 - Engelhard, Carsten A1 - Kaul, Peter T1 - Optimized fast gas chromatography coupled with proton-transfer-reaction time-of-flight mass spectrometry for the selective near real-time analysis of herbivore-induced plant volatiles N2 - The analysis of herbivore-induced plant volatiles (HIPVs) is essential for understanding plant-environment interactions and defense strategies against herbivores. Proton transfer reaction time-of-flight mass spectrometry (PTR–TOF–MS) is a powerful analytical tool that enables real-time monitoring and quantification of diverse groups of HIPVs. However, the PTR–TOF–MS technique is constrained in its ability to effectively differentiate between isomers. When analyzing complex mixtures of HIPVs, the separation of isomers becomes crucial as major compound classes such as terpenes comprise thousands of isomers. In this study, we present an optimized fast gas chromatography (fastGC) based on a modified version of the commercially available fastGC add-on integrated into a mobile PTR–TOF. The system was optimized for the analysis of emissions from enclosed trunks of Acer platanoides infested by Anoplophora glabripennis (Motschulsky), commonly known as Asian longhorned beetle (ALB). The development of fastGC was primarily focused on the sesquiterpenes α-longipinene, cyclosativene and α-copaene, which serve as strong indicators of ALB infestation. These sesquiterpenes were separated in less than three minutes, with intra-day retention time RSD < 0.6 % and resolutions of 2.6 ± 0.3 and 1.3 ± 0.2. In comparison to the original system, the optimized fastGC demonstrates more than tripled sesquiterpene resolution, twice the sensitivity relative to direct inlet mode, and an approximately 10 % reduction in total analysis time. The optimized fastGC–PTR–TOF allows for near real-time analysis of complex mixtures of biogenic VOCs, making it a powerful tool for environmental monitoring, integrated pest management, and forest protection. KW - Mass Spectrometry KW - PTR-TOF-MS KW - Gas Chromatography KW - Herbivore-induced plant volatiles KW - Sesquiterpenes PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-639513 DO - https://doi.org/10.1016/j.chroma.2025.466236 SN - 0021-9673 VL - 1759 SP - 1 EP - 16 PB - Elsevier B.V. AN - OPUS4-63951 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -