Faculty Profiles - MINAMI, Masayo

Papers - MINAMI, Masayo

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Carbon and nitrogen isotope fractionations of collagen by treatment with XAD-2 adsorption resin

Minami Masayo

Summaries of Researches using AMS at Nagoya University ( 10 ) page： 235 - 242 1999.3

AMS <14>^C age of a Molar fossil of Maumann's elephant : with XAD-2 resin

Minami Masayo, Nakamura Toshio

Summaries of Researches using AMS at Nagoya University ( 10 ) page： 139 - 148 1999.3

Publisher：Nagoya University

The predominant contaminants such as humic and fulvic acids affect ^<14>C date and stable isotope analyses in fossil bone. The XAD-2 treatment of collagen hydrolysate is considered an effective method to eliminate the foreign organic matter from bone. In this study, we have conducted ^<14>C dating, by the XAD-2 method, on a molar fossil of Naumann's elephant (Palaeoloxodon naumanni) collected from the Uwa-sea, offshore Natori-kajitanihana, Nishi-Uwa-gun, Ehime prefecture. The ^<14>C date of 29,200±870 yr BP was already obtained for gelatin collagen by gelatin-extraction method of decalcification in a cellulose tube with 1.2N HCl, followed by heating at 90℃ in water (Nakamura et al., 1998). Three parts of dentine, enamel and cement in the molar fossil were separated for each ^<14>C dating. The samples were decalcificated with 4℃, 0.8N HCl and the acid-insoluble residues were concentrated by centrifugation and lyophilized. The demineralized fractions were hydrolysed with 6N HCl at 110℃. The filtered hydrolysates were passed through the XAD-2 resin to remove fulvic and humic acids. Dentine phase in the molar fossil gives older ^<14>C age than enamel and cement phases. It is thought that the dentine, covered with enamel and cement phases, is better-preserved. The ^<14>C age of the XAD-purified hydrolysates (XAD) is older than that of solution collagen (SC), but coincide with age of gelatin collagen (GC) in dentine phase. Enamel phase gives different C/N ratio, δ ^<13>C and δ ^<15>N values from those of dentine and cement phases, and relatively younger age, which indicates that the majority of enamel protein has decomposed and changed to hydroxyapatite. All fulvic fractions (F) of three phases give significantly younger ages than bone organic carbon. The molar fossil might be well-preserved because of the higher yield (1.22%) of gelatin collagen more than 1%. The gelatin-extraction method is sufficient for ^<14>C dating on the well-preserved fossil.

DOI： 10.18999/sumrua.10.139

The <14>^C AMS facility of the Nagoya University : present status of the Tandetron-I and -II AMS systems

Nakamura Toshio, Oda Hirotaka, Ikeda Akiko, Niu Etsuko, Minami Masayo, Yoshioka Shigeo, Ohta Tomoko, Takahashi Hiroshi A, Adachi Mamoru, Pals Ludi

Summaries of Researches using AMS at Nagoya University ( 10 ) page： 5 - 17 1999.3

Publisher：Nagoya University

A Tandetron accelerator mass spectrometer, an apparatus dedicated to high sensitivity radiocarbon (^<14>C) measurements, manufactured by General Ionex Corporation, USA, has been used since 1983 to measure the ^<14>C concentrations of environmental samples as well as ^<14>C dates of geological and archaeological materials, at the Dating and Materials Research Center, Nagoya University. The authors present here a brief review of the present performance and some archaeological and geological applications of the Tandetron-I AMS, as well as a brief introduction to a so-called second generation AMS machine, an AMS ^<14>C dating apparatus, currently of the highest performance, manufactured by High Voltage Engineering Europe, BV, the Netherlands, which has been recently installed at the Dating and Materials Research Center. Results of the recent performance tests of the Tandetron-II AMS machine are briefly described.

DOI： 10.18999/sumrua.10.5

AMS <14>^C age of Japanese wolf collected from the cave at Mt. Kyozyo in Izumi-mura, Yashiro-gun, Kumamoto Prefecture

Minami Masayo, Kitamura Naoshi, Nakamura Toshio

Summaries of Researches using AMS at Nagoya University ( 10 ) page： 189 - 198 1999.3

Carbon and nitrogen isotope fractionations of collagen by treatment with XAD-2 adsorption resin

Vol. X page： 235-242 1999

AMS ¹⁴C age of a Molar fossil of Naumann's elephant -with XAD-2 resin-

Vol. X page： 139-148 1999

Status Report of ^<14>C Measurements with the First Tandetron AMS at Nagoya University in the Year of 1997 and Installation of a Second-Generation High-Performance AMS System

NAKAMURA Toshio, ODA Hirotaka, IKEDA Akiko, MINAMI Masayo, ADACHI Mamoru

Summaries of Researches using AMS at Nagoya University ( 9 ) page： 126 - 139 1998.3

Publisher：Nagoya University

A Tandetrno accelerator mass spectrometer (AMS), an apparatus dedicated to radiocarbon (^<14>C) measurements with high sensitivity, manufactured by General Ionex Corporation, USA, has been used since 1983 to measure ^<14gt;C concentrations of environmental samples as well as ^<14>C dates of geological and archeological materials at the Dating and Materials Research Center (DMRC), Nagoya University. No serious problem has occurred with the machine, which resulted in that 770 samples were measured in 1997,and totally 7,371 samples in various fields have been measured since the installation of the machine. Though the Tandetron AMS has been operated intensively, the number of samples analyzed annually is rather limited to several hundreds which is far smaller than the number of samples brought to the DMRC by many users from various research fields, mainly owing to lower negative current intensity from an ion source (HICONEX-844,modified for loading 18 targets at a time), as well as a rather low throughput of the total system. We could have fortunately introduced a new-generation Tandetron which is manufactured by High Voltage Engineering Europe (HVEE) BV, the Netherlands. Two sets of similar HVEE AMS system have been installed successfully at the University of Groningen, Holland, and at the University of Christian-Albrechts, Kiel, Germany. They have already shown excellent performances in carbon-isotope-ratio measurments : reproducibility of ^<12>C/^<13>C ratio as ±0.1%; error and reproducibility of ^<14>C/^<12>C ratio as ±0.15%-±0.22% and ±0.3%, respectively. We are planning to perform high accuracy and high precision ^<14>C dating of mainly cultural property materials of historical age, archeological and geological samples, by using the new-generation machine.

DOI： 10.18999/10.19999/sumrua.9.126

AMS ^<14>C Age of Collagen Separated from a Molar Fossil of Naumann's Elephant Collected from the Uwa-sea, Ehime Prefecture

NAKAMURA Toshio, OHTA Tomoko, MIYAMOTO Masazo, MINAMI Masayo, ODA Hirotaka, IKEDA Akiko

Summaries of Researches using AMS at Nagoya University ( 9 ) page： 286 - 297 1998.3

Publisher：Nagoya University

We have conducted ^<14>C dating, with a Tandetron accelerator mass spectrometer (AMS) at Nagoya University, on carbon from collagen fractions extracted from a molar tooth fossil of Naumann's elephant (Palaeoloxodon naumanni) collected from the Uwa-sea, offshore Natori-Kajitanihana, Nishi-Uwa-gun, Ehime prefecture. The molar fossil was cleaned on the surface with a steel brush and a dental grinder, treated with 0.5M NaOH solution, and ground into powder. Two sets of the powdered sample, about 3.8g and 4.9g each, were demineralized with 1.2N HCl in a cellulose tube to extract collagen. After demineralization, HCl was completely removed from the tube by dialysis. Then the solution fraction in the tube was separated by centrifuge, and freeze-dried to get a solution-collagen fraction. Solid remains were put in a Pyrex tube with 20ml of distilled water and heated at 90℃ for 10 hours to extract the water soluble gelatin-collagen fraction. Collagen was oxidized, using CuO to produce CO_2,in a Vycor tube at 950℃ for an hour. A small aliquot of the CO_2 was analyzed for its' stable carbon isotope ratio, δ ^<13>C_<PDB>, using a triple-collector mass spectrometer (MAT-252). To produce graphite, the remaining CO_2 was reduced by hydrogen, with an Fe-powder catalyst, in a Vycor tube at 650℃ for several hours. The sample graphite was analyzed for its' ^<14>C/^<13>C ratio, relative to that of an oxalic acid standard (NBS-SRM-4990). In general, reliable ^<14>C dates can be obtained for collagen fractions extracted from the fossil sample, provided that the collagen fractions have been preserved well from weathering in nature. Experimental yields of collagen fractions were relatively high, ranging from 1.22 to 1.51%. The CO_2 yield from the gelatin collagen fraction was 42%, being consistent with the values of 41-42% for gelatin collagen extracted from fresh bone samples. On the other hand, the CO_2 yield from the solution fraction was 25%, being lower than the values of 41-42%. Thus the ^<14>C date of 29,200±870 yr BP, obtained for the gelatin collagen fraction, seems to be reliable and can be assigned as the age of the molar fossil sample, though the ^<14>C date is about 4,000 years older than the value of 24,880±580 yr BP obtained for the solution collagen fraction. The δ ^<13>C_<PDB> values of -20.2‰ for the both gelatin and solution collagen fractions were consistent with accepted δ ^<13>C_<PDB> values, of from -21 to -23‰ for herbivorous mammals.

DOI： 10.18999/10.19999/sumrua.9.286

Analytical note of stable nitrogen isotopic measurements with MAT-252 mass spectrometer at Dating and Materials Research Center, Nagoya University

MINAMI Masayo, AOKI Hiroshi, NAKAMURA Toshio

Summaries of Researches using AMS at Nagoya University ( 9 ) page： 316 - 323 1998.3

Publisher：Nagoya University

This paper provides a basic experimental information of stable nitrogen isotopic measurements with MAT-252 mass spectrometer (Finnigan MAT Ltd.) at Dating and Materials Research Center, Nagoya University, and a refining method of N_2 gas from sample gas on vacuum line. The ion output voltage from 28 collector is directly proportional to N_2 gas pressure. In case that ion output voltage from 28 collector of N_2 gas is more than 1.6V, the ratio of [29]/[28] hardly varies according to the output voltage, and the pressure effect on nitrogen isotopic ratios can be disregarded. The 28 ion output voltage of 2.5V (N_2 gas pressure around 38mb) is recommended on normal measurements. Only N_2 gas can be separated and refined from a sample gas by means of molecular sieves on vacuum line for refining CO_2. The δ^<13>C values do not change by collecting N_2.

DOI： 10.18999/10.19999/sumrua.9.316

Extraction and radiocarbon dates of amino acids in fossil bones

Vol. IX page： 46-54 1998

Isotope fractionation by XAD-2 treatment

Vol. IX page： 308-311 1998

Status Report of <14>^C Measurements with a Tandetron AMS at Nagoya University in the Year of 1996 and Installation of a second-Generation High-Performance AMS System

Nakamura Toshio, Ikeda Akiko, Ohta Tomoko, Minami Masayo, Adachi Mamoru

Summaries of Researches using AMS at Nagoya University ( 8 ) page： 56 - 67 1997.3

Publisher：Nagoya University

A Tandetron accelerator mass spectrometer (AMS), an apparatus dedicated to radiocarbon (^<14>C) measurements with high sensitivity, manufactured by General Ionex Corporation, USA, has been used since 1983 to measure ^<14>C concentrations of environmental samples as well as ^<14>C dates of geological and archeological materials at the Dating and Materials Research Center (DMRC), Nagoya University. No serious problem has occurred with the machine, which resulted in that 708 samples were measured in 1996,and totally 6,300 samples in various fields have been measured since the installation of the machine. Though the Tandetron AMS has been operated intensively, the number of samples analyzed annually is rather limited to several hundreds which is far smaller than the number of samples brought to the DMRC by many users from various research fields, mainly owing to lower negative current intensity from an ion source (HICONEX-844,modified for loading 18 targets at a time), as well as a rather low throughput of the total system. We could have fortunately introduced a new-generation Tandetron which is manufactured by High Voltage Engineering Europe (HVEE) BV, the Netherlands. Two sets of similar HVEE AMS system have been installed successfully at University of Groningen, Holland, and at University of Christian-Albrechts, Kiel, Germany. They have already shown excellent performances in carbon-isotope-ratio measurements : reproducibility of ^<12>C/^<13>C ratio as ア0.1% ; error and reproducibility of ^<14>C/^<12>C ratio as ア0.15-0.22% and ア0.3%, respectively. We are planning to perform high accuracy and high precision ^<14>C dating of mainly cultural property materials of historical age, archeological and geological samples, by using the new-generation machine.

DOI： 10.18999/sumrua.8.56

AMS Radiocarbon Dates of Wood, Mammalian Bone and Shell Fossils Collected from the Same Horizons of a Shell Mound Excavated at Awazu Submarine Archeological Site, Shiga Prefecture

Nakamura Toshio, Ohta Tomoko, Iba Isao, Minami Masayo, Ikeda Akiko

Summaries of Researches using AMS at Nagoya University ( 8 ) page： 237 - 246 1997.3

Publisher：Nagoya University

The Awazu submarine archeological site, 2-3 meters below the water surface, is located at southern basin of Lake Biwa, near the mouth of Seta River flowing out of the Lake Biwa. A shell mound was excavated during the 1990-1991 year survey of the site. Seven sets of wood, mammalian bone, and shell fossil samples collected from the same layers of the shell mound were dated with the AMS radiocarbon method. The ^<14>C dates for each of the three kinds of samples did not show big difference between the seven layers. This tendency is consistent with the fact that the shell mound was formed within ca. 100 years, because pottery fragments of the Funamoto-I type, which corresponds to early stage of the middle Jomon, were preferentially discovered from this shell mound. However, ^<14>C dates were systematically different among three types of samples : shell fossil samples showed the oldest dates from 4800-5080yr BP, except for a very young date (4630+/-80yrBP); wood samples did the middle ones (4570-4760yrBP); and bone fragment samples did the youngest ones (4090-4430yrBP). The reasons for the difference of ^<14>C dates among the three kinds of samples collected from the same horizons are not clarified yet. Shell carbonate originates from dissolved inorganic carbon in the lake water, which carbon was produced partly in the dissociation of old organic materials in the lake sediment and was also added with dead carbon from limestone rock surrounding Lake Biwa. In addition, younger carbon contaminated the bone samples when the samples were in the sediment may not have been removed completely during chemical preparation procedures of the samples.

DOI： 10.18999/sumrua.8.237

An attempt on accurate radiocarbon and carbon isotope measurements of fossil bone

Minami Masayo, Nakamura Toshio

Summaries of Researches using AMS at Nagoya University ( 8 ) page： 247 - 253 1997.3

Publisher：Nagoya University

Accurate radiocarbon (^<14>C) and carbon isotope measurements on fossil bones require that all exogenous carbon be removed. The remove the foreign organic carbon and obtain reliable ^<14>C ages from bones, XAD-2 chromatography method was examined. The fossil bones used in the experiment were bone fragments collected from the Awazu submarine archeological site. The bone samples were demineralized with 4℃ 0.8N HCl and the acid-insoluble residue was concentrated by centrifugation and lyophilized. The demineralized bone powder was hydrolysed with 6N HCl at 110℃. Solids were removed by centrifugation before the filtered hydrolysate was passed through the XAD-2 resin to remove fulvic and humic acids. δ^<13>C values and ^<14>C ages for three fractions of decalcified bone powder, XAD-treated hydrolysate, and fulvic and humic acids in demineralization-hydrolysis-XAD treatment procedure. XAD-purified hydrolysates have more positive δ^<13>C values and older ^<14>C ages than gelatin collagen extracted by conventional method. The δ^<13>C values in fulvic and humic phases are significantly more negative than collagen fractions. Conventional collagen extraction method is sufficient for ^<14>C dating on well-preserved bones but insufficient on poorly-preserved bones, because the method does not totally remove exogenous organic carbon. XAD-2 resin is recommended for accurate ^<14>C and carbon isotope measurements.

DOI： 10.18999/sumrua.8.247

Geochronological and geochemical study for the Archean cherts in Pilbara Block, Western Australia

Minami Masayo

Chikyukagaku Vol. 31 ( 4 ) page： 244 - 244 1997

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