Investigation of Pathogenic Escherichia coli Contamination of Vegetables Distributed in a Korean Agricultural Wholesale Market.

The purpose of this study was to investigate the monthly contamination rate of pathogenic Escherichia coli, a major cause of food poisoning, in vegetables sold in agricultural wholesale markets, which distribute vegetables from all over the country, in the Incheon Metropolitan City area, South Korea, and to identify a source of the pathogen. In total, 1739 vegetables of 80 types, along with 109 soil, 67 manure, and 33 livestock feces samples, were tested for pathogenic E. coli using polymerase chain reaction, from September 2016 through August 2017. The average annual prevalence rate of vegetables was 5.8%, and the prevalence rate was above 5% from June through October. The highest prevalence rate (15.7%) was recorded in July. Water dropwort showed the highest prevalence rate (28.6%) among the vegetables examined. Pathogenic E. coli was detected in >20 types of the vegetables that were to be consumed without cooking. Among these, the prevalence rates of ponytail radish (n = 21), crown daisy (n = 86), young radish (n = 68), romaine lettuce (n = 133), perilla leaf (n = 103), Korean leek (n = 43), young Chinese cabbage (n = 68), and Chinese cabbage (n = 30) were 9.5%, 8.1%, 7.4%, 6.8%, 4.9%, 4.7%, 4.4%, and 3.3%, respectively. Among the vegetables cooked before consumption, prevalence rates were 28.6%, 27.3%, and 25.0% in wormwood, sweet potato stalk, and edible mountain vegetables (Saussurea sp., etc.), respectively. In soil, manure, and livestock feces, 36.7%, 26.9%, and 90.6% prevalence rates were confirmed, respectively. This study confirmed the pathogenic E. coli contamination of vegetables to be consumed without cooking. Therefore, to produce agricultural products that do not induce food poisoning and are safe for consumption, it is important to develop a process for killing the pathogenic microorganisms and set up a sanitary environment for effectively managing compost. In addition, it is necessary to establish surveillance systems to monitor the production chain.

End-Site-Specific Conjugation of Enoxaparin and Tetradeoxycholic Acid Using Nonenzymatic Glycosylation for Oral Delivery.

Heparin and low molecular weight heparins (LMWHs) have been the drug of choice for the treatment or the prevention of thromboembolic disease. Different methods are employed to prepare the LMWHs that are clinically approved for the market currently. In particular, enoxaparin, which has a reducing sugar moiety at the end-site of polysaccharide, is prepared by alkaline depolymerization. Focusing on this end-site-specific activity of LMWHs, we conjugated the tetraoligomer of deoxycholic acid (TetraDOCA; TD) at the end-site of enoxaparin via nonenzymatic glycosylation reaction. The end-site-specific conjugation is important for polysaccharide drug development because of the heterogeneity of polysaccharides. This study also showed that orally active enoxaparin and tetraDOCA conjugate (EnoxaTD) had therapeutic effect on deep vein thrombosis (DVT) without bleeding in animal models. Considering the importance of end-specific conjugation, these results suggest that EnoxaTD could be a drug candidate for oral heparin development.