A preparative method for the purification of isopenicillin N from genetically blocked Acremonium chrysogenum strain TD189: studies on the degradation kinetics and storage conditions

Abstract

A protocol for preparative isopenicillin N (IPN) purification, a highly interesting and hitherto unavailable intermediate of the penicillin and cephalosporin biosynthetic pathway due to its high unstability, is described. Culture broths of Acremonium chrysogenum TD189, a strain blocked in cephalosporin biosynthesis that accumulates this metabolite, were treated with acetone and filtered though charcoal and a hydrophobic resin in a single step as tandem columns. The cleared broth was then lyophilized and passed though a Sephadex G-25 column. The last step was the purification to homogeneity of IPN in a semipreparative HPLC equipment and, optionally, a desalting step by Sephadex G-10 column. Once purified, a complete analysis of the stability of the compound and the conditions for its long-term storage was carried out. Our results suggest a first-order model for IPN decomposition for all the pH and temperature analyzed. IPN is more stable at neutral pH, and once lyophilized, can be stored under vacuum and À75 1C with a half-life of 770 days.

Isolation, characterization and chromatography based purification of antibacterial compound isolated from rare endophytic actinomycetes Micrococcus yunnanensis

“…3 ). HPLC with optimized conditions was found to be very effective for final purification of antibacterial compound [22] . The result of bioassay against S. aureus showed 1.4-fold increases in antibacterial activity.…”

Precursor-directed combinatorial biosynthesis of cephalosporin analogue by endolithic actinobacterium Streptomyces sp. AL51 by utilizing thiophene derivative

“…TLC-bioautography is a significant tool to localize antibacterial activity which was also employed in our research work to locate R f value of the compound (Choma and Grzelak 2011). The antibiotic was further purified by preparative TLC, Sephadex LH-20 column (Choma and Grzelak 2011;Lee et al 2003) and semi-preparative HPLC (Vaca et al 2011).…”

The isolation of water-soluble natural products – challenges, strategies and perspectives

“…427 More recent examples of chromatography on Sephadex G-10 for the isolation of water-soluble natural products include the isolation of leuhistin (117) as an inhibitor of aminopeptidase M, 428 isopenicillin N (118) from a mutant of Acremonium chrysogenum TD189 (ref. 429) and the nematocide (À)-echinobetaine A (119) from the marine sponge Echinodictyum sp. 430 Sephadex G-15 is cross-linked dextran similar to Sephadex G-10, but it is suitable for the separation of compounds within the MW range above 1500 Da.…”