Carbendazim, fungicide

Microtubulin Polymerization Inhibitors. The ben2imida2oles were first reported to have systemic fungicidal activity in 1964 (29). Prominent examples include thiabendazole [148-79-8] (42) fuberida2ole [3878-19-1] (43) carbendazim [10605-21-7] (44) benomyl [17804-35-2] (45) and thiophanate methyl [23564-05-8] (46). Benomyl (45), the most widely used member of this group is almost certainly inactive as a fungicide until it is converted in plants and soil to carbendazim (44). Likewise, thiophanate and thiophanate methyl (46) are nonfungitoxic until converted to carbendazin (44). 

A method has been reported for the quantification of five fungicides (shown in Figure 5.39) used to control post-harvest decay in citrus fruits to ensure that unacceptable levels of these are not present in fruit entering the food chain [26]. A survey of the literature showed that previously [27] APCl and electrospray ionization (ESI) had been compared for the analysis of ten pesticides, including two of the five of interest, i.e. carbendazim and thiabendazole, and since it was found that APCl was more sensitive for some of these and had direct flow rate compatibility with the HPLC system being used, APCl was chosen as the basis for method development. 

The widely used insecticide carbaryl (FD50=270 mg/kg) transforms in oxidizing processes into 5-oxynaphthyl-N-methylcarbamate, a substance that is as toxic as carbaryl itself (FD50=297 mg/kg) [30, 33]. One of the metabolites of the fungicide benomyl, the methyl ester carbamino acid (BMK, carbendazim), is also toxic to fungi [33]. 

The mutagenic aminophenazines 71 are present as impurities of carbendazim (72) fungicides and its formulations. They were determined by HPLC-UVD (diode array), using 0.02% sulfuric acid in MeOH, and measuring at 270 and 453 nm186. 

Whereas the fungicides carbendazim and drazoxolon were effective in controlling the disease, calcium peroxide was also effective (26). This compound had the added advantage of releasing alkali to... 

Pressurized hot water can be used to extract two fungicides, thiabendazole (TBZ), and carbendazim (MBC), from agricultural commodities including banana pulp, whole lemons, orange pulp, mushrooms, and rice at extraction temperatures below 100°C and an extraction pressure of 50 atm. The extraction parameters that were studied include temperature, equilibration time, flow rate, pH, and collection volume. Liquid-... 

Methyl benzimidazol-2-ylcarbamate (47), known as carbendazim, and some of its derivatives such as benomyl (48), are potent broad spectrum systemic fungicides (B-77MI10703). They are synthesized straightforwardly from o-phenylenediamine (b-... 

Relation between sublethal (EC50) or lethal (LC50) toxicity values (pg/L) and exposure duration (in hours) for the microcrustacean Daphnia magna, the macrocrustacean Gammarus pulex, and the flatworm Dugesia lugubris exposed to the fungicide carbendazim... 

Daam MA, van den Brink PJ. 2003. Effects of three pesticides that differ in mode of action on the ecology of small indoor aquatic microcosms an evaluation of the effects of the insecticide chlorpyrifos, the herbicide atrazine and the fungicide carbendazim. Report No. 788. Wageningen (The Netherlands) Alterra. 

All benzimidazole fungicides (benomyl, carbendazim, fuberidazole, thiabendazole) and thiophanate fungicides are cross-resistant. However, the reeently diseovered fungicide, zoxamide, which also inhibits the B-tubulin assembly, is not cross-resistant in oomycetes... 

As regards foods, water has been used for the dynamic extraction of fungicides such as thiabendazole and carbendazim from fruits and vegetables, with recoveries of 80.9-100.5% at fortification levels of 0.14-100 ppm [40]. 

Thiophanate methyl (74) is, like thiabendazole (54), a member of the benzimidazole group of fungicides since it is metabolised in vivo to carbendazim (83), which is the active entity. Thiophanate methyl is synthesised by condensation of o-phenylenediamine (82) with potassium thiocyanate and methyl chloroformate (Scheme 17). The benzimidazoles owe their fungicidal action to the inhibition of cell division in the fungus due to interference with the microtubular assembly. 

Mull RL and Hershberger LW (2001) Inhibitors of DNA biosynthesis-mitosis Benimidizoles - the benzimidazole fungicides benomyl and carbendazim. In Krieger R (ed.) Handbook of Pesticide Toxicology, 2nd edn., pp. 1673-1699. San Diego, CA Academic Press. 

Some years ago, two groups of compounds, i.e. If-phenylcarbamates and N-phenylformamidoximes were synthesized in Japan and their specific antifungal activity against benzimidazole-resistant strains was reported ( 2, 3J. In France, where benzimidazole-resistant strains of the gray mold Botrvtis cinerea predominate in some areas, a N-phenylcarbamate compound diethofencarb is already in use as a mixture with a benzimidazole fungicide carbendazim. 

Thiophanate must also be transformed to carbendazim in order to be fungicidal. It is active against a wide variety of fungal pathogens and has low toxicity. In soil and plants it is slowly transformed into carbendazim. 

Carbendazim was first described as a fungicide in 1973 and is active against a wide variety of fungi. 

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