Lemon Balm and Corn Silk Extracts Mitigate High-Fat Diet-Induced Obesity in Mice.

Lemon balm and corn silk are valuable medicinal herbs, which exhibit variety of beneficial effects for human health. The present study explored the anti-obesity effects of a mixture of lemon balm and corn silk extracts (M-LB/CS) by comparison with the effects of single herbal extracts in high-fat diet (HFD)-induced obesity in mice. HFD supplementation for 84 days increased the body weight, the fat mass density, the mean diameter of adipocytes, and the thickness of fat pads. However, oral administration of M-LB/CS significantly alleviated the HFD-mediated weight gain and adipocyte hypertrophy without affecting food consumption. Of the various combination ratios of M-LB/CS tested, the magnitude of the decreases in weight gain and adipocyte hypertrophy by administration of 1:1, 1:2, 2:1, and 4:1 (w/w) M-LB/CS was more potent than that by single herbal extracts alone. In addition, M-LB/CS reduced the HFD-mediated increases in serum cholesterol, triglyceride, and low-density lipoprotein, prevented the reduction in serum high-density lipoprotein, and facilitated fecal excretion of cholesterol and triglyceride. Moreover, M-LB/CS mitigated the abnormal changes in specific mRNAs associated with lipogenesis and lipolysis in the adipose tissue. Furthermore, M-LB/CS reduced lipid peroxidation by inhibiting the HFD-mediated reduction in glutathione, catalase, and superoxide dismutase. Therefore, M-LB/CS is a promising herbal mixture for preventing obesity.

Prevalence of Toxoplasma gondii infection in household and feral cats in Korea.

This study was designed to investigate the prevalence rate of Toxoplasma gondii (T. gondii) infection in household cats in Korea. One hundred household cats and 50 feral cats from nine of the largest cities in Korea were enrolled in this study. The tests performed in this survey was an in-house rapid screen IgG and IgM combo test, faecal PCR test for T. gondii oocysts, and an ELISA immunoassay for IgG antibodies. There were no household cats positive for T. gondii infection detected using the in-house IgG and IgM rapid screen combo test, although 6/50 and 0/50 feral cats were positive in IgG and IgM tests, respectively. This initial finding was confirmed by subsequent ELISA test for IgG antibody and PCR for T. gondii in faeces. Despite the higher prevalence rate of the disease in feral cats in Korea, we did not find any household cats that were either infected or exposed previously to T. gondii in our study population. Our study indicates that there is minimal risk of T. gondii transmission from household cats to human in Korea.

Identification and distribution of Bacillus species in doenjang by whole-cell protein patterns and 16S rRNA gene sequence analysis.

Many bacteria are involved in fermentation of doenjang and Bacillus species are known to perform significant roles. Although the SDS-PAGE technique has been frequently used for classification and identification of bacteria in various samples, there has been no investigation of the microbial diversity in doenjang. This study aims to investigate the identification and distribution of dominant Bacillus species in doenjang using SDS-PAGE profiles of whole cell proteins and 16S rDNA sequencing. SDS-PAGE of whole cell proteins of the reference Bacillus strains yielded differential banding patterns that could be considered to be highly specific fingerprints. Bacterial strains isolated from doenjang samples were grouped using whole cell protein patterns, which were confirmed by the analysis of 16S rDNA sequencing. B. subtilis was found to be the most dominant strain in most of the samples, and B. licheniformis and B. amyloliquefaciens were less frequently detected. The results obtained in this study showed that a combined identification method, SDS-PAGE patterns of whole cell proteins and subsequent 16S rDNA sequence analysis, could successfully identify Bacillus species isolated from doenjang.

Analysis of microbial communities in doenjang, a Korean fermented soybean paste, using nested PCR-denaturing gradient gel electrophoresis.

Doenjang is a traditional Korean fermented soybean paste that provides a major source of protein. The microbial diversity of 10 samples of doenjang (5 commercially manufactured products and 5 homemade products) was investigated using nested PCR-denaturing gradient gel electrophoresis (DGGE). In the first step, the nearly complete 16S rRNA and 18S rRNA genes were amplified using universal primers. Subsequently, these products were used as a template in a nested PCR to obtain fragments suitable for DGGE. The bacterial DGGE profile targeting the V3 region of the 16S rRNA gene indicated that lactic acid bacteria such as Leuconostoc mesenteroide, Tetragenococcus halophilus, and Enterococcus faecium were the predominant species. However, bands corresponding to Bacillus species, known to be the main organisms in doenjang, were not detected under the conditions described above. When selective PCR was conducted using a primer specific for Bacillus species, Bacillus subtilis and B. licheniformis were detected in several doenjang samples. In analysis of fungi, Mucor plumbeus, Aspergillus oryzae, and Debaryomyces hansenii were the most common species in the doenjang samples. On the basis of DGGE, a few differences in community structure were found for different samples. Also, cluster analysis of the DGGE profile revealed that the microbial diversity did not differ clearly between commercially manufactured and homemade products. The nested PCR-DGGE technique was used for the first time in this study to asses a microbial community in doenjang and proved to be effective in profiling microbial diversity.