Jean Bastide

Dimethylphthalate hydrolysis by specific microbial esterase

TWO BACTERIAL STRAINS: Arthrobacter sp. and Sphingomonas paucimobilis were isolated from soil by enrichment cultures using dimethylphthalate (DMP) or monomethylphthalate (MMP) as sole carbon source, respectively. DMP was rapidly transformed by an Arthrobacter sp. culture with formation of MMP and phthalic acid (PA) which is further degraded. This strain was unable to hydrolyse MMP. A mechanism of degradation of DMP was proposed with two ways: DMP-->PA and DMP-->MMP. The S. paucimobilis strain hydrolyses only MMP and a coculture of the two strains allowed a complete degradation of DMP.

Synthesis and cytotoxic evaluation of analogues of the marine pyridoacridine amphimedine.

4-Substituted-7H-pyrido-[4,3,2-de][1,8] or [1,9]-phenanthroline-7-ones and 9-methyl-1,4-diazanaphtacene-3,10-dione, analogues of the marine pyridoacridine amphimedine were synthesised from isoquinoline-5,8-dione. The first compounds were obtained starting from a Diels-Alder reaction whereas the synthesis of the last compound was initiated by a reaction of condensation with 2-aminoacetophenone. The different tetra- and pentacyclic compounds were evaluated for in vitro cytotoxic activities against six distinct human cancer cell lines. All the compounds exhibit cytotoxic activity with IC(50) values (i.e., the drug concentration inhibiting the mean growth value of the six cell lines by 50%)<10(-7)M for two of them.

Total synthesis of the marine pentacyclic alkaloid meridine

Abstract The synthesis of the marine pyridoacridine alkaloid meridine (1) has been accomplished in eight steps from 2,5-dimethoxy-3-nitroaniline in 9% overall yield.

Total synthesis of the marine pyridoacridine alkaloid sebastianine A

Abstract The synthesis of the marine alkaloid sebastianine A and of a regioisomer has been accomplished via hetero-Diels–Alder reaction of indole-4,7-dione or N -tosylindole-4,7-dione with trifluoroacetamidocinnamaldehyde dimethylhydrazone, and subsequent cyclisation in alkaline conditions.

Synthesis and in vitro antitumor activity of an isomer of the marine pyridoacridine alkaloid ascididemin and related compounds.

The isomer (9H-quino[4,3,2-de][1,7]phenanthroline-9-one) (2) of the marine alkaloid ascididemin (9H-quino[4,3,2-de][1,10]phenanthroline-9-one) (1) has been synthesized in six steps from 1,4-dimethoxyacridine (10) with an overall yield of 12%. Different related compounds were prepared and tested in vitro at six different concentrations on 12 different human cancer cell lines of various histopathological types (glioblastomas and breast, colon, lung, prostate and bladder cancers). Almost all the compounds present cytotoxic activity of micromolar order.

Enhanced degradation of iprodione in soil after repeated treatments for controlling Sclerotinia minor

Poor field control of lettuce collar rot by iprodione was observed in southern France and was attributed to enhanced biodegradation of the fungicide. Enhanced biodegradation was obtained in vitro after repeated applications of iprodione to non-degrading soils. Normal soils became biodegrading after mixing with degrading soils (3 vol./1 vol.). Activity of the responsible microflora seemed dependent on soil physico-chemical characteristics.

Isolation from soil and growth characteristics of a cipc-degrading strain of Pseudomonas cepacia

Abstract A bacterial strain, identified as Pseudomonas cepacia , was isolated from soil and had the ability to utilize phenyl carbamates (BIPC, CIPC) as the sole source of carbon and energy. The degradation of CIPC, at various concentrations, was studied in a minimal medium. The addition of yeast extract increased bacterial growth, decreased the degradation-lag period, and increased the rate of CIPC transformation. The bacterial isolate also utilized 3-chloroaniline, the degradation product of CIPC. Its ability to degrade the herbicide was retained despite repeated growth in media without the herbicide.

Degradation of phenyl carbamate herbicides by Pseudomonas alcaligenes isolated from soil

Abstract A bacterial strain isolated from soil and identified as Pseudomonas alcaligenes, was able to hydrolyze four phenylcarbamate herbicides (CIPC, BIPC, IPC and swep) to corresponding anilines and alcohols by co-metabolism. The pH of the growth medium had little influence on bacterial growth and rate of herbicide transformation. Increase in CIPC and BIPC concentrations resulted in a significant inhibition of bacterial growth and herbicide degradation. Using a range of antibiotics it was shown that the enzyme involved in degradation was inducible.

Structure revision of the marine pentacyclic aromatic alkaloid: cystodamine

The structure of cystodamine, a polycyclic aromatic alkaloid from the mediterranean ascidian Cystodytes delle chiajei has been revised to be 11-hydroxyascididemin, by comparison of the spectroscopic data with those of synthetic cystodamine, meridine and 11-hydroxyascididemin.

Metabolism of iprodione in adapted and non-adapted soils; Effect of soil inoculation with an iprodione-degrading Arthrobacter strain

Abstract Soils previously treated with iprodione degraded the fungicide more rapidly than previously-untreated samples of the same soils. Addition of an iprodione-degrading Arthrobacter sp. culture to a previously-untreated soil enhanced the degradation rate of the fungicide. In previously-untreated soils, chemical and biological transformations of iprodione led to different products. In previously-treated soils and in previously-untreated soils enriched with Arthrobacter sp., the product obtained from the hydrolysis of exocyclic urea function of iprodione was transformed initially into 3,5-dichlorophenylurea acetic acid, which was then further degraded to 3,5-dichloroaniline. Experiments showed that soil adaptation leading to enhanced iprodione degradation was related to the ability of microorganisms to make the first transformation step.