Metabolism of the persistent plasticizer chemical bis(2-ethylhexyl) phthalate in cell suspension cultures of wheat (Triticum aestivum L. ). Discrepancy from the intact plant

Journal Article · · J. Agric. Food Chem.; (United States)

DOI:https://doi.org/10.1021/jf00068a010· OSTI ID:5878160

Krell, H W; Sandermann, H Jr

Cell suspension cultures of wheat (Triticum aestivum L.) metabolized the persistent plasticizer chemical bis(2-ethylhexyl) phthalate (DEHP; 1 ppm) predominantly to ..beta..-D-glucosyl conjugates. After incubation for 48 h at 27/sup 0/C, 23% of the applied radioactively labeled chemical was recovered in the total polar metabolite fraction. Prior heat treatment of freeze-thawing of the wheat cells abolished conjugate formation and led to mono(2-ethylhexyl) phthalate (MEHP)) as the predominant metabolite (up to 10% conversion). Direct feeding of MEHP to native wheat cells led to 93% conversion to polar metabolites, again consisting largely of ..beta..-D-glucosyl conjugates. This suggested that MEHP was a metabolic intermediate and that DEHP esterase activity was rate limiting in DEHP metabolism. The rate of cellular DEHP metabolism in fact agreed with the rate of the DEHP esterase reaction determined in crude cell-free extracts. Therefore, no significant permeation barrier between the intracellular enzyme and external DEHP appeared to exist in cell suspension cultures. In contrast, the DEHP esterase activity of intact leaves has previously been found to be inaccessible to external DEHP.

• Research Organization: Universitaet Freiburg, West Germany
• OSTI ID: 5878160
• Journal Information: J. Agric. Food Chem.; (United States), Journal Name: J. Agric. Food Chem.; (United States) Vol. 34:2; ISSN JAFCA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
CARBON 14 COMPOUNDS
CELL CULTURES
CEREALS
ENZYME ACTIVITY
ESTERS
GRASS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
METABOLISM
METABOLITES
ORGANIC COMPOUNDS
PHTHALIC ACID ESTERS
PLANTS
REACTION INTERMEDIATES
TRACER TECHNIQUES
WHEAT