Electronic supplementary Material_1
Sequential thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), detailed method and control samples
TD/Py-GC-MS was performed on a CDS Pyroprobe 1000 via a CDS1500 valved interface (320°C), to a Hewlett-Packard 5890GC  split injector (280°C) linked to a Hewlett-Packard 5973MSD (electron voltage 70eV, filament current 220uA, source temperature 230°C,  quadrupole temperature 150°C, multiplier voltage 2200V, interface temperature 340°C). The acquisition was controlled by a HP kayak xa chemstation computer, in full scan mode (50-700amu). Approximately 2-3mg of ground sample was weighed into a quartz tube with glass wool end plugs. The tube was placed into a pyroprobe platinum heating coil and sealed into the valved interface. The sample was thermally desorbed at 310°C for 10secs in open split mode at 30mls/minute. At the same time the GC temperature programme and data acquisition commenced. Separation was performed on a fused silica capillary column (30m x 0.25mm i.d) coated with
0.25um 5% phenyl methyl silicone (DB-5). Initially the GC was held at 35°c for 5 minutes and then temperature programmed from 40°C-340°C at 6°C min and held at final temperature for 15 minutes, total
65 minutes, with Helium as the carrier gas (constant flow 1ml/min, initial pressure of 45kPa, split at 30 mls/min). The run was repeated with the same sample being pyrolysed at 610°C for 10 seconds with the split open.
Modern control samples.electronic去掉ic是什么
Four control samples of dental calculus including a modern (Hoy) sheep and an (Alsatian) dog, and two samples from the Victorian cemetery of St Barnabas, London were used for comparative purposes to assist in the interpretation of the El Sidrón material (Figures S1, S2, S3, S4).
Historical (Victorian) human calculus, St Barnabus, sample 1
By comparison to Neanderthal sample SDR007, the presence of i-C15 and ai-C15, and i-C16and ai-C16alkenes, with no n-alkane counterparts in samples of modern human calculus (Figure S1, S2) is indicative of microbially-derived components which have undergone relatively little diagenetic change.This is corroborated by the presence of significant amounts of cholesterol derivatives, with cholest-3-ene being the major component, in the TD-GC-MS; cholesterol is virtually absent in bacterial cell membranes (Shorland1962), these sterols resulting from in situ modification of the original food lipids by bacteria in the mouth.
Figure S1 Reconstructed total ion chromatogram of the pyrolysis profile (610ºC for 10s) of Historical (V
ictorian) human calculus, St Barnabus 10, 5.3mg, after thermal desorption (310ºC for 10s). Peak identities (x indicates carbon chain length): filled squares, C x indicates alkenes; filled circles, C x indicates alkanes; open diamonds, C x:y indicates acyclic nitriles; open pentagons indicates alkyl pyrroles; open hexagons indicates alkyl pyridines. Also shown are the structures of five aromatic compounds identified: benzene, toluene, styrene, indene and indole, and the steroidal compound: cholest-3-ene. Inset displays a reconstructed total ion chromatogram of the thermal desorption profile (310ºC for 10s) of this sample. Peak identities: filled squares, C x indicates alkenes; open diamonds, C x:y indicates acyclic nitriles. Peaks labelled a to e were identified as steroidal compounds: a = a cholestadiene, b = cholest-4-ene, c = a cholestatriene, d = a cholestatriene, e = cholesta-1,3,5,7-tetraene. Also shown are the
structures of two aromatic compounds identified: pyridine and indole, and the steroidal compound identified: cholest-3-ene.
Historical (Victorian) human calculus, St Barnabus, sample 2
Figure S2 Reconstructed total ion chromatogram of the pyrolysis profile (610ºC for 10s) of Historical (V
ictorian) human calculus, St Barnabus 54, 2.9mg, after thermal desorption (310ºC for 10s). Peak identities (x indicates carbon chain length): filled squares, C x indicates alkenes; filled circles, C x indicates alkanes; open diamonds, C x:y indicates acyclic nitriles; open pentagons indicates alkyl pyrroles; open hexagons indicates alkyl pyridines; N within conjoined open hexagons and pentagons indicates alkyl indoles. Peak 1 is 2-methyl-2-cyclopenten-1-one and 2 is 2,3-dimethyl-2-cyclopenten-1-one. Also shown are the structures of four aromatic compounds
identified: benzene, toluene, styrene and indole. Inset displays a reconstructed total ion chromatogram of the thermal desorption profile (310ºC for 10s) of this sample. Peak identities: filled diamonds, C x:0 indicates saturated fatty acid methyl esters; open diamonds, C x:y indicates acyclic nitriles; filled squares, C x indicates alkenes; filled circles, C x indicates alkanes. Peaks labelled a to d were identified as the steroidal compounds: a = a cholestadiene, b = a cholestene, c = a cholestene, d = a cholestane. Peak dd is dimethyl disulfide, peak s is an unidentified sesquiterpenoid and peak 1 was tentatitively identified as 1,4:3,6-dianhydro-α-D-glucopyranose. Also shown are the structures of the steroidal compound: cholest-3-ene and the cyclic lactone: oxacycloheptadecan-2-one (juniper lactone), both identified in the TD.
Sheep dental calculus sample, Hoy 560

版权声明：本站内容均来自互联网，仅供演示用，请勿用于商业和其他非法用途。如果侵犯了您的权益请与我们联系QQ:729038198，我们将在24小时内删除。