The oxidation of secondary organic aerosol (SOA) is studied with mass spectra analysis of SOA formed in a Potential Aerosol Mass (PAM) chamber, a small flow-through photo-oxidation chamber with extremely high OH and ozone levels. The OH exposure from a few minutes in the PAM chamber is similar to that from days to weeks in the atmosphere. The mass spectra were measured with a Quadrupole Aerosol...

Traditionally, nisin was produced industrially by using Lactococcus lactis in the neutral fermentation process. However, nisin showed higher activity in the acidic environment. How to balance the pH value for bacterial normal growth and nisin activity might be the key problem. In this study, 17 acid-tolerant genes and 6 lactic acid synthetic genes were introduced in L. lactis F44, respectively....

The heterogeneous oxidation of laboratory Secondary Organic Aerosol (SOA) particles by OH radicals was investigated. SOA particles, produced by reaction of αpinene and O3, were exposed to OH radicals in a flow tube, and particle chemical composition, size, and hygroscopicity were measured to assess modifications due to oxidative aging. Aerosol Mass Spectrometer (AMS) mass spectra indicated that...

Two new fungal metabolites, penicipyrone (1), and penicilactone (2), were isolated from the marine-derived fungus Penicillium sp. PSU-F44 along with three known macrolides, (+)-brefeldin A (3), (+)-brefeldin C (4), and 7-oxobrefeldin A (5). Their antimicrobial activities against methicillin-resistant Staphylococcus aureus SK1 and Microsporum gypseum SH-MU-4 were examined.

In this study we compile and present results from the factor analysis of 43 Aerosol Mass Spectrometer (AMS) datasets (27 of the datasets are reanalyzed in this work). The components from all sites, when taken together, provide a holistic overview of Northern Hemisphere organic aerosol (OA) and its evolution in the atmosphere. At most sites, the OA can be separated into oxygenated OA (OOA), hydr...

BACKGROUND Probiotics, especially in combination with non-digestible oligosaccharides, may balance the gut microflora while multistrain preparations may express an improved functionality over single strain cultures. In vitro gastrointestinal models enable to test survival and growth dynamics of mixed strain probiotics in a controlled, replicable manner. METHODS The robustness and compatibilit...

DNA topoisomerase I (TOP1) mediates the induction of radiosensitization (RS) by camptothecin derivatives in mammalian cells. Many indolocarbazole (INDO) derivatives have been shown to induce TOP1-mediated DNA damage (T1DD). In the current study, we characterized the cytotoxic and radiosensitizing activities of six INDO derivatives in relation to their efficiencies to induce T1DD. Evaluated by c...

Airborne measurements of biomass burning organic aerosol (BBOA) from boreal forest fires reveal highly contrasting properties for plumes of different ages. These measurements, performed using an Aerodyne Research Inc. compact time-of-flight aerosol mass spectrometer (C-ToF-AMS) during the BORTAS (quantifying the impact of BOReal forest fires on Tropospheric oxidants over the Atlantic using Airc...