Title: | A comparison of semi-quantitative methods suitable for establishing volatile profiles |
Author(s): | Ruiz-Hernandez V; Roca MJ; Egea-Cortines M; Weiss J; |
Address: | "1Instituto de Biotecnologia Vegetal, Universidad Politecnica de Cartagena, Cartagena, Spain. ISNI: 0000 0001 2153 2602. GRID: grid.218430.c 2Departamento de Ciencia y Tecnologia Agraria, Universidad Politecnica de Cartagena, Cartagena, Spain. ISNI: 0000 0001 2153 2602. GRID: grid.218430.c 3Servicio de Apoyo a la Investigacion Tecnologica, Universidad Politecnica de Cartagena, Cartagena, Spain. ISNI: 0000 0001 2153 2602. GRID: grid.218430.c" |
DOI: | 10.1186/s13007-018-0335-2 |
ISSN/ISBN: | 1746-4811 (Print) 1746-4811 (Electronic) 1746-4811 (Linking) |
Abstract: | "BACKGROUND: Full scent profiles emitted by living tissues can be screened by using total ion chromatograms generated in full scan mode and gas chromatography-mass spectrometry technique using Headspace Sorptive Extraction. This allows the identification of specific compounds and their absolute quantification or relative abundance. Quantifications ideally should be based on calibration curves using standards for each compound. However, the unpredictable composition of Volatile Organic Compounds (VOCs) and lack of standards make this approach difficult. Researchers studying scent profiles therefore concentrate on identifying specific scent footprints i.e. relative abundance rather than absolute quantities. We compared several semi-quantitative methods: external calibration curves generated in the sampling system and by liquid addition of standards to stir bars, total integrated peak area per fresh weight (FW), normalized peak area per FW, semi-quantification based on internal standard abundance, semi-quantification based on the nearest n-alkane and percentage of emission. Furthermore, we explored the usage of nearest components and single calibrators for semi-quantifications. RESULTS: Any of the semi-quantification methods based on a standard produced similar or even identical results compared to quantification by a true-standard for a compound, except for the method based on standard addition. Each method beholds advantages and disadvantages regarding level of accuracy, experimental variability, acceptance and retrieved quantities. CONCLUSIONS: Our data shows that, except for the method of standard addition to the biological sample, the rest of the semi-quantification methods studied give highly similar statistical results. Any of the methodologies presented here can therefore be considered as valid for scent profiling. Regarding relative proportions of VOCs, the generation of calibration curves for each compound analysed is not necessary" |
Keywords: | Calibration curve Gc-ms Hsse Internal standard Quantification Scent profile Stir bars Twisters VOCs; |
Notes: | "PubMed-not-MEDLINERuiz-Hernandez, Victoria Roca, Maria Jose Egea-Cortines, Marcos Weiss, Julia eng England 2018/08/14 Plant Methods. 2018 Aug 9; 14:67. doi: 10.1186/s13007-018-0335-2. eCollection 2018" |