Rapid identification of bast fibers in ancient handmade papers based on improved characterization of lignin monomers by Py-GCxGC/MS

Abstract

The precise identification of hemp (Cannabis sativa L.) fiber in ancient papers is of great significance in the study of paper history. However, different species of phloem fibers belonging to bast fibers (e.g., hemp, ramie, flax, jute) used in traditional hand papermaking in the East Asian region present similar microscopic morphological traits, which renders their accurate identification problematic and may cause controversy in archaeological interpretations. In this study, a method for the precise identification of Cannabis fiber in ancient handmade papers by Py-GCxGC/MS was developed for rapid fiber characterization in ancient papers. The proposed approach was based on the separation of characteristic lignin monomers from lignocellulose by Py-GCxGC/MS, with an example of joss paper samples excavated from the archaeological site of Astana tombs dating to the Tang Dynasty. The bidimensional chromatographic separation of the pyrolysis signature of plant materials allows a wellstructured layout in the 2D chromatograms. Therefore, it becomes possible to distinguish these different plant materials by applying a multivariate analysis treatment to the lignin monomers.The improved GCxGC separation of lignin monomers showed the benefit of the GCxGC profile for lignin monomer group identification as well as for the application of statistical analysis. The developed method presents the advantages of being rapid and effective for archaeological and cultural heritage applications in necessitating a tiny quantity of sample.

Chemical profiling of a 130‐year‐old manuscript reveals the early use of synthetic lead white correction fluid in ancient China

“…In addition, in pyrolysis at lower temperature (Figure S3), the paper acidic deterioration biomarker of levoglucosenone was low, indicating that the manuscript has not suffered from acidic deterioration and retained thermal stability (Ohtani et al, 2009). Together with its low levels of lignin monomers, it could originate from other bast fibers (Han et al, 2019, 2023). A check of the 1726 bronze‐type repaint version (Figure 2) revealed that some texts on the page were intentionally painted out by a whitish correction fluid layer for reasons such as the naming taboo, a cultural taboo against using the Chinese characters related to the name of the emperors enforced by several laws throughout Imperial China.…”

Species Identification of Palm Leaf Manuscript Based on Py-GC/MS

“…Recently, the lignin of four paper samples made of jute (Corchorus capsularis), ramie (Boehmeria nivea), ax (Linum usitatissimum), and hemp (Cannabis sativa) were analyzed. Signi cant distinction in the S/G ratio in the four bers of the jute paper samples was detected, and the bers were further analyzed to determine the botanical origins of the ancient paper samples [22].…”

Analysis of fabrics obtained during the archeological excavation sites in Israel

“…This include identification of the material from which the fabric was made through chemical and spectral analysis. 17,18 Methods such as, Fourier transform infrared spectrometry (FTIR), [19][20][21][22] nuclear magnetic resonance (NMR), 23,24 pyrolysis-gas liquid chromatography (Pyr-GLC), 25 x-ray analysis, 26 Raman imaging, scanning electron microscope (SEM) 27,28 are useful in identifying the composition of the fabrics.…”