Glucosides detoxification

The QSAR data show that glucuronidation can be either a detoxification or bioactivation mechanism, depending chemical structure. For N SAIDs, it appears to be mostly a detoxification mechanism. Nonetheless, the toxicity of acyl glucuronide and glucoside adducts (espedally as it relates to isomerization and protein adduct formation) must be considered when designing carboxylic acids [38]... 

Frear, D.S., E.R. Mansager, and H.R. Swanson (1981). N-glucoside conjugates Major metribuzin detoxification products in tomato. Presented to the North Central Weed Control Conference in Des Moines, Iowa. Miles Ag. Div. Report Number 80304.2... 

Several members of the Poaceae were checked for BOA detoxification capacity the results are presented in Table 4.1. All species, with one exception, contained the A/-glucoside, although there were remarkable differences in the accumulated amounts following incubation at 24 h and 48 h. Zea mays exhibited the most effective detoxification capacity, as BOA-6-O-glucoside was synthesized in traces only or was a minor product. The A/-glucosylated compound already... 

The synthesis of BOA-6-O-glucoside is catalyzed by constitutive enzymes that may be upregulated. A glucosyltransferase that accepted BOA-6-OH as a substrate was measurable in protein extracts of corn roots harvested from control plants. Detoxification via glucoside carbamate synthesis is inducible and seems to be more complicated than simple A/-glucosylation (data unpublished). The biosynthesis of the compounds is part of our ongoing research. 

We tested a number of dicot species for their ability to detoxify BOA. Most of them were incubated as seedlings but some as adult plants when germination failed under laboratory conditions. Applied BOA concentration was 100 and 500 pM, incubation time was 24 h. The plants were separated into roots and shoots after incubation and the material extracted with 30% methanol. HPLC analyses of the extracts revealed remarkable differences in the detoxification capacities. Major detoxification appeared within the roots, whereas shoots were only involved when roots seemed to be overtaxed. All species tested were able to perform BOA-6-O-glucoside synthesis, but with regard to glucoside carbamate synthesis, differences became obvious (Table 4.2). 

BOA detoxification capacity of several weeds with regard to glucoside carbamate synthesis within 24 h. 

It is clear that BOA detoxification, mainly via glucoside carbamate production of the species tested, is not a feature of certain plant families but is rather combined with their occurrence in defined plant communities where benzoxazinone containing character species exist with high density covers. Plantago major is regarded as an exception. 

Sicker, D., Schneider, B., Hennig, L., Knop, M., and Schulz, M. 2001. Glucoside carbamate from benzoxazolin-2(3H)-one detoxification in extracts and exudates of corn roots. Phytochemistry 58, 819-825... 

DE Duggan, JJ Baldwin, BH Arison, RE Rhodes. N-glucoside formation as a detoxification mechanism in mammals J Pharmacol Exp Ther 190(3) 563—569,1974. 

Cytokinin 7- and 9-glucosides are biologically relatively inactive [128-130] and they are not substrates for plant 3-glucosidases [130,131]. Thus they are proposed to be detoxification or simply inactivation products [92]. 

Formation of these amino acid conjugates is catalysed by p-(9-cytokinin)-aIanine synthase, classified as C-N ligase, and characterised in lupin seeds [134]. The enzyme requires O-acetylserine as donor of the alanine moiety and recognises all main cytokinin bases (including BA) and many other purine derivatives as substrates. Similarly to cytokinin 7- and 9-glucosides, also cytokinin 9-alanyl derivatives are biologically inactive and metabolically stable, and are therefore candidates to be cytokinin-inactivation and detoxification products. 

Isol. from wheat, in which it is present mainly as glucoside. Appears to be a natural aphicide and fungicide. Involved in the in vivo detoxification of herbicides, e.g. Simazine. Pink needles. Mp 156-157° dec. 

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