Electronic Journal of Polish Agricultural Universities (EJPAU) founded by all Polish Agriculture Universities presents original papers and review articles relevant to all aspects of agricultural sciences. It is target for persons working both in science and industry,regulatory agencies or teaching in agricultural sector. Covered by IFIS Publishing (Food Science and Technology Abstracts), ELSEVIER Science - Food Science and Technology Program, CAS USA (Chemical Abstracts), CABI Publishing UK and ALPSP (Association of Learned and Professional Society Publisher - full membership). Presented in the Master List of Thomson ISI.

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Górski Z. , Rolewski P. , Sławińskia D. , Sławiński J. 2004. CHEMILUMINESCENCE IMAGING OF THE FORMATION AND PHOTODEGRADATION OF HUMIC ACID DERIVED FROM 5-HYDROXY-1,4-NAPHTHOQUINONE (JUGLONE), EJPAU 7(2), #04.
Available Online: http://www.ejpau.media.pl/volume7/issue2/environment/abs-04.html

ABSTRACT

A new model humic acid (HA) have been synthetized from 5-hydroxy-1,4-naphthoquinone (juglone, J), an allelopathic compound occuring in leaves, nut shells, exsudates of roots and barks of Juglans genera. Aqueous solutions of J were autooxidised at different pH 6-10 with mineral matrices: bentonite, glass and silica. The very slow autooxidation reaction was monitored by means of chemiluminescence (CL) imaging and kinetics supported by a highly sensitive CCD camera Molecular Light Imager. In the course of autooxidation that lasted three weeks, an extremely low-intensity of CL was detected The reaction liquid was further treated according to the IHSS protocol to isolate humic acid fractions. Elemental analysis, UV-VIS and FTIR absorption spectra as well as fluorescence excitation and emission spectra were measured to characterise this new HA. Juglone-derived HA (JHA) in Na₂CO₃ was irradiated with UVC (254 nm) and induced changes in the UV-VIS absorption

Key words: juglone, toxicity, synthesis of humic acids, chemiluminescence, photodegradation.

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