TY - JOUR
T1 - Characterization of the perylenequinone pigments in Japanese Andosols and Cambisol
AU - Kobayashi, Takayuki
AU - Rasmussen, Craig
AU - Sumida, Hiroaki
N1 - Funding Information:
This work was supported by the Japan Society for the Promotion of Science [grant number 17K18154] and Sugiyama Houkoukai [grant number 2015-03].
Funding Information:
This work was supported by the Japan Society for the Promotion of Science [grant number 17K18154] and Sugiyama Houkoukai [grant number 2015-03]. The authors thank Dr. Nobuyasu Itoh (National Institute of Advanced Industrial Science and Technology (AIST)) for supplying synthesized DHPQ samples. The authors also thank Dr. Taku Kato of Kobe University (currently, Tokyo University of Agriculture) for sampling KB soil. A word of thanks also goes to Dr. Wataru Hakamata of Nihon University for valuable suggestion regarding isolation of CEGF components and Dr. Prakash Dhakal of The University of Arizona for helpful comments and grammatical correction of this manuscript.
Publisher Copyright:
© 2018, © 2018 Japanese Society of Soil Science and Plant Nutrition.
PY - 2019/1/2
Y1 - 2019/1/2
N2 - The green fraction of humic acid (Pg) and the chloroform-extractable green fraction (CEGF) are characteristic soil organic matter (SOM) components. These alkaline solutions are green-colored due to the presence of 4,9-dihydroxyperylene-3,10-quinone (DHPQ) chromophore. While both of which are potential indicators for the effect of land use and paleoclimatic environment in the fields of soil science as well as geochemistry, CEGF as well as its relationship with Pg in soils are not yet fully documented. In this study, we firstly investigated the chemical properties of soil CEGF fractions by ultraviolet–visible (UV–Vis) and infrared (IR) method. Two CEGF components were separated by sequential liquid-liquid extraction using aqueous ammonium hydroxide (NH 4 OH) followed by aqueous sodium hydroxide (NaOH). Results showed that the UV–Vis spectral shape of NH 4 OH-extractable component is very similar to that of DHPQ, except that it is red-shifted. The solubility and UV–Vis spectrum of the NaOH-extractable fraction were completely identical with those of synthesized DHPQ. Their IR spectral shapes were also almost the same. Subsequently, the distribution of CEGF in humic acid (HA), fulvic acid (FA) and humin (HN) from Japanese Andosols and Cambisol was quantitatively evaluated by sequential extraction. Most of CEGF was detected in the HA (60–78%) and HN (22–40%), but not in the FA. While the UV–Vis spectral shape of CEGF extracted from Andosols HAs showed a relatively higher proportion of DHPQ than its derivative, the opposite was observed in Cambisol HA, whose CEGF is similar to that of sclerotium grain (one of the possible origin of CEGF). These results suggest the diversity of CEGF-producing soil fungi. Quantitative data also indicated that 35–49% of Pg consisted of a chloroform-soluble fraction (i.e., CEGF) and the remaining 51–65% of Pg was chloroform-insoluble. Based on these results, we propose that CEGF is composed of DHPQ and DHPQ-derivatives and that CEGF is one of the major fractions of Pg.
AB - The green fraction of humic acid (Pg) and the chloroform-extractable green fraction (CEGF) are characteristic soil organic matter (SOM) components. These alkaline solutions are green-colored due to the presence of 4,9-dihydroxyperylene-3,10-quinone (DHPQ) chromophore. While both of which are potential indicators for the effect of land use and paleoclimatic environment in the fields of soil science as well as geochemistry, CEGF as well as its relationship with Pg in soils are not yet fully documented. In this study, we firstly investigated the chemical properties of soil CEGF fractions by ultraviolet–visible (UV–Vis) and infrared (IR) method. Two CEGF components were separated by sequential liquid-liquid extraction using aqueous ammonium hydroxide (NH 4 OH) followed by aqueous sodium hydroxide (NaOH). Results showed that the UV–Vis spectral shape of NH 4 OH-extractable component is very similar to that of DHPQ, except that it is red-shifted. The solubility and UV–Vis spectrum of the NaOH-extractable fraction were completely identical with those of synthesized DHPQ. Their IR spectral shapes were also almost the same. Subsequently, the distribution of CEGF in humic acid (HA), fulvic acid (FA) and humin (HN) from Japanese Andosols and Cambisol was quantitatively evaluated by sequential extraction. Most of CEGF was detected in the HA (60–78%) and HN (22–40%), but not in the FA. While the UV–Vis spectral shape of CEGF extracted from Andosols HAs showed a relatively higher proportion of DHPQ than its derivative, the opposite was observed in Cambisol HA, whose CEGF is similar to that of sclerotium grain (one of the possible origin of CEGF). These results suggest the diversity of CEGF-producing soil fungi. Quantitative data also indicated that 35–49% of Pg consisted of a chloroform-soluble fraction (i.e., CEGF) and the remaining 51–65% of Pg was chloroform-insoluble. Based on these results, we propose that CEGF is composed of DHPQ and DHPQ-derivatives and that CEGF is one of the major fractions of Pg.
KW - 4,9-dihydroxyperylene-3,10-quinone (DHPQ)
KW - chloroform-extractable green fraction (CEGF)
KW - green fraction of humic acid (Pg)
KW - perylenequinone
KW - sclerotium grain
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U2 - 10.1080/00380768.2018.1536846
DO - 10.1080/00380768.2018.1536846
M3 - Article
AN - SCOPUS:85055735577
SN - 0038-0768
VL - 65
SP - 1
EP - 10
JO - Soil Science and Plant Nutrition
JF - Soil Science and Plant Nutrition
IS - 1
ER -