A high-penicillin-yielding strain of Penicillium chrysogenum was grown in continuous culture on a chemically defined medium with glucose as the growth-limiting component. The cultivations were operated at a constant dilution rate of 0.05 h and the feed concentration of the penicillin V sidechain precursor phenoxyacetic acid was varied between 0 and 6.5 g l. Subsequent formation of penicillin V and by-products related to the penicillin biosynthetic pathway was monitored at steady state. It was established that the concentration of phenoxyacetic acid in the growth medium had to be kept high to obtain a high productivity of penicillin V. The specific production rate of penicillin V as a function of the phenoxyacetic acid concentration followed Michaelis--Menten-type kinetics, from which an overall apparent K value of 42 mM for the incorporation of intracellular phenoxyacetic acid into penicillin V could be obtained. High phenoxyacetic acid concentrations tended to lower the formation of the by-products 6-aminopenicillanic acid and 8-hydroxypenillic acid. Furthermore the undesirable loss of the pathway intermediate isopenicillin N into the extracellular medium was lowered, whereas the opposite effect was observed for the pathway intermediate δ-(L-α-aminoadipyl)-L-cysteinyl-D-valine and the by-product 6-oxo-piperidine-2-carboxylic acid, the δ-lactam form of α-aminoadipic acid.
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http://dx.doi.org/10.1099/00221287-144-7-2001 | DOI Listing |
J Hazard Mater
January 2025
College of the Environment and Ecology, Xiamen University, Xiamen 361005, China; Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Xiamen University, Xiamen 361005, China. Electronic address:
Due to the high toxicity and increasing consumption, efficient removal of phenoxyacetic acid herbicides (PAAHs) from water is imperative. In current study, a new adsorbent was prepared by modifying porous carbon derived from disused floral foam with chitosan (CS) (ACFC). Density functional theory (DFT) calculation uncovered that the amino and hydroxyl groups in the introduced CS played a critical role in the efficient adsorption of ACFC towards PAAHs.
View Article and Find Full Text PDFArch Toxicol
December 2024
Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
2-Phenoxyethanol (PhE) is an amphiphilic organic compound frequently used as a broad-spectrum preservative in cosmetic products and other consumer goods. PhE is also used as a biocidal component in occupational settings. A previous volunteer study by our working group following oral exposure to PhE showed that PhE is almost completely taken up into the human body followed by an extensive metabolization and fast urinary elimination.
View Article and Find Full Text PDFBioorg Chem
January 2025
School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai 201418, China. Electronic address:
A phenoxyacetate ester Schiff base lead compound 4a (ZINC20073984) was firstly discovered through molecular docking screening and molecular dynamics (MD) simulation, which could be used as an α-glucosidase (PDB: 3A4A) inhibitor. Then a series of α-glucosidase inhibitors 4b-4r with novel structures were designed and synthesized with the lead ZINC20073984 as a template. The results of in vitro α-glucosidase inhibitory activity show that the synthesized phenoxyacetate ester Schiff base compounds 4e, 4o-4r (IC values range from 5.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
October 2024
Departament of Biology, Federal University of the Espírito Santo, Alto Universitário, s/n, Alegre, ES, 29500-000, Brazil.
Chem Commun (Camb)
October 2024
School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430205, China.
Photoredox-catalyzed cross-coupling reaction is an efficient strategy for the construction of organic molecules. Herein, we developed a method to synthesize α-arylthioanisoles by constructing C-S bonds in the presence of a Ru-photoredox catalyst. Thus, a series of α-arylthioanisole compounds were efficiently obtained through decarboxylative cross-coupling under mild conditions.
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