Monascus pigments suppress fructose-mediated BSA glycation by trapping methylglyoxal and covalent binding to proteins.

In this study, four Monascus pigments (ankaflavin, AK; monascin MS; rubropunctatin, O; monascorubrin, O) were proved to exhibit considerable anti-glycation properties in bovine serum albumin (BSA)-fructose model. AK (40.62 %) and MS (48.

Insight into enzyme-catalyzed aziridine formation mechanism in ficellomycin biosynthesis.

Ficellomycin is an aziridine-containing antibiotic, produced by Streptomyces ficellus. Based on the newly identified ficellomycin gene cluster and the assigned functions of its genes, a possible pathway for aziridine ring formation in ficellomycin was proposed, which is a complex process involving at least 3 enzymatic steps. To obtain support for the proposed mechanism, the targeted genes encoding sulfate adenylyltransferase, adenylsulfate kinase, and a putative sulfotransferase were respectively disrupted and the subsequent analysis of their fermentation products revealed that all the three genes were involved in aziridine formation.

The immunomodulatory effect of docosahexaenoic acid (DHA) on the RAW264.7 cells by modification of the membrane structure and function.

Background: DHA can regulate various physiological functions of cells. Our group has clarified the immunomodulatory activity and molecular mechanism of DHA on RAW264.7 cells.

Divalent oseltamivir analogues as potent influenza neuraminidase inhibitors.

A panel of divalent oseltamivir and guanidino oseltamivir analogues with esterification on the carboxyl acid group as potent inhibitors of influenza virus neuraminidase was prepared via click reaction. The primary structure activity relationship study demonstrated that appropriate distance between two oseltamivir monomers around 30 Å can crosslink two adjacent neuraminidase tetramers on the virion surface and result in highly effective NA inhibitors against three strains of influenza virus and H7N9 virus like particle. This strategy also provides a basis for the multivalent modification on oseltamivir.

Enhancement of bioelectricity generation via heterologous expression of IrrE in Pseudomonas aeruginosa-inoculated MFCs.

Low electricity power output (EPT) is still the main bottleneck limited the industrial application of microbial fuel cells (MFCs). Herein, EPT enhancement by introducing an exogenous global regulator IrrE derived from Deinococcus radiodurans into electrochemically active bacteria (EAB) was explored using Pseudomonas aeruginosa PAO1 as a model strain, achieving a power density 71% higher than that of the control strain. Moreover, IrrE-expressing strain exhibited a remarkable increase in the total amount of electron shuttles (majorly phenazines compounds) and a little decrease in internal resistance, which should underlie the enhancement in extracellular electron transfer (EET) efficiency and EPT.

Access to 8-Azachromones via Activation of C-H in N-Oxides.

A concise and practical synthetic method has been developed for 8-azachromones, including 8-azaflavones, which have emerged as a promising class of compounds. Using commercially available nicotinates as the starting material, 8-azachromones were obtained in only three steps. The key intramolecular O-arylation reaction was achieved by nucleophilic attack of enolates to C2 of N-oxides under PyBrop or AcO activation conditions.

Identification and characterization of the ficellomycin biosynthesis gene cluster from Streptomyces ficellus.

Ficellomycin is a peptide-like antibiotic which exhibits potent in vitro activity against Penicillium oxalicum and Staphylococcus aureus, even against strains resistant to most clinically used antibiotics. The gene cluster responsible for ficellomycin biosynthesis was cloned from Streptomyces ficellus and sequenced. It was found to contain 26 ORFs and is located within 30 kb of contiguous DNA.

A Shortcut to the Optimization of Cellulase Production Using the Mutant Trichoderma reesei YC-108.

Trichoderma reesei YC-108, a strain isolated by a kind of newly invented plate was found to over produce cellulase and it was then used as a cellulase producer. To get the maximum amount of cellulase, the combination of the medium ingredients, which has a profound influence on metabolic pathway was optimized using response surface methodology. The optimum composition was found to be 24.

[A multi-step distillation method for sample preparation in gas chromatographic analysis].

A sample pretreatment device based on multi-step distillation principle was constructed and evaluated. Trace components in the sample were extracted, separated and enriched at the cold receptor of the molecular diffusion distillation device. The cold receptor was designed as an exchangeable part to avoid the cross interferences from one sample to another one.