Transcriptional Profiling of the Effect of Coleus amboinicus L. Essential Oil against Salmonella Typhimurium Biofilm Formation.

Salmonella enterica serovar Typhimurium cause infections primarily through foodborne transmission and remains a significant public health concern. The biofilm formation of this bacteria also contributes to their multidrug-resistant nature. Essential oils from medicinal plants are considered potential alternatives to conventional antibiotics. Therefore, this study assessed the antimicrobial and antibiofilm activities of Coleus amboinicus essential oil (EO-CA) against S. Typhimurium ATCC 14028. Seventeen chemical compounds of EO-CA were identified, and carvacrol (38.26%) was found to be the main constituent. The minimum inhibitory concentration (MIC) of EO-CA for S. Typhimurium planktonic growth was 1024 µg/mL while the minimum bactericidal concentration was 1024 µg/mL. EO-CA at sub-MIC (≥1/16× MIC) exhibited antibiofilm activity against the prebiofilm formation of S. Typhimurium at 24 h. Furthermore, EO-CA (≥1/4× MIC) inhibited postbiofilm formation at 24 and 48 h (p < 0.05). Transcriptional profiling revealed that the EO-CA-treated group at 1/2× MIC had 375 differentially expressed genes (DEGs), 106 of which were upregulated and 269 were downregulated. Five significantly downregulated virulent DEGs responsible for motility (flhD, fljB, and fimD), curli fimbriae (csgD), and invasion (hilA) were screened via quantitative reverse transcription PCR (qRT-PCR). This study suggests the potential of EO-CA as an effective antimicrobial agent for combating planktonic and biofilm formation of Salmonella.

The peripheral blood mononuclear cells preparation and the hematology of Varanus salvator.

The objectives of this study were to evaluate the proper anticoagulants coated in blood-collecting tube for the peripheral blood mononuclear cells (PBMCs) isolation and to evaluate the proper culture temperature for the Varanus salvator's PBMCs, in addition, the hematological characteristics also reported. The heparin treated blood (n = 10) and EDTA treated blood (n = 10) from Varanus salvator were obtained for PBMCs evaluation. The PBMCs obtained from the heparin treated blood was significantly higher than that of EDTA treated blood during the culture period (P < 0.05) indicated heparin would be more appropriated anticoagulant for blood collection. The PBMCs cultured under 37°C and 27°C were not significantly difference on first three days but 37°C showed significantly higher effect in the following days (P < 0.05) indicated both temperatures can be used which 37°C should be an optimal for PBMCs preparation. The peripheral blood cells of Varanus salvator (n = 49) were analyzed for hematological profiles and characteristics which the number of erythrocytes 1.19 ± 0.04 x 1012/L (1.17-1.35 x 1012/L) and WBC 2.41 ± 0.13 x 109/L (2.29-2.81 x 109/L) with absolute differential count of heterophils 0.92 ± 0.02 x 109/L (0.87-0.95 x 109/L), lymphocytes 1.17 ± 0.01 x 109/L (1.15-1.23 x 109/L), azurophils 0.40 ± 0.01 x 109/L (0.37-0.42 x 109/L), basophils 0.000 ± 0.001 x 109/L (0.004-0.011 x 109/L) and monocytes 0.027 ± 0.002 x 109/L (0.028-0.039 x 109/L). These results would play an important role on the cell immunological studies of the Varanus salvator in the future.

Natural Antioxidant, Antibacterial, and Antiproliferative Activities of Ethanolic Extracts from Punica granatum L. Tree Barks Mediated by Extracellular Signal-Regulated Kinase.

The nonedible parts of the pomegranate plant, such as tree barks and fruit peels, have pharmacological properties that are useful in traditional medicine. To increase their value, this study aimed to compare the antioxidative and antibacterial effects of ethanolic extracts from pomegranate barks (PBE) and peels (PPE). The antiproliferative effects on HeLa and HepG2 cells through the extracellular signal-regulated kinase pathway were also evaluated. The results indicated that the total amounts of phenolics and flavonoids of PBE and PPE were 574.64 and 242.60 mg equivalent gallic acid/g sample and 52.98 and 23.08 mg equivalent quercetin/g sample, respectively. Gas chromatography−mass spectrometry revealed that 5-hdroxymethylfurfural was the major component of both PBE (23.76%) and PPE (33.19%). The 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical scavenging capacities of PBE and PPE, in terms of the IC50 value, were 4.1 and 9.6 µg/mL, respectively. PBE had a greater potent antibacterial effect against Escherichia coli, Staphylococcus aureus, Salmonella Enteritidis, and S. Typhimurium. PBE and PPE (1000 µg/mL) had exhibited no cytotoxic effects on LLC-MK2. PBE and PPE (250 and 1000 µg/mL, respectively) treatments were safe for BHK-21. Both extracts significantly inhibited HepG2 and HeLa cell proliferations at 10 and 50 µg/mL, respectively (p < 0.001). The results indicated that PBE and PPE have remarkable efficiencies as free radical scavengers and antibacterial agents, with PBE exhibiting greater efficiency. The inhibitory effects on HepG2 might be through the modulation of the ERK1/2 expression. PBE and PPE have the potential for use as optional supplementary antioxidative, antibacterial, and anticancer agents.

Overview of avian influenza virus in urban feral pigeons in Bangkok, Thailand.

This survey assessed the presence of avian influenza virus (AIV) in urban feral pigeons (UFPs) in Bangkok, Thailand. A total of 485 UFPs were collected from eight study sites, and blood, tracheal, and cloacal samples were collected from each bird. Virus isolation and molecular methods did not detect AIV in any of the birds tested. A hemagglutination inhibition test was used to test for antibodies to high and low pathogenicity AIV subtypes. AIV subtype H9 antibodies were the only antibodies detected. The overall seroprevalence of AIV subtype H9 antibodies was 6.9%, and subtype H9 antibodies were found in UFPs at all eight sites. The overall geometric mean titer was 11.07 (range: 8-64). These results reveal that UFPs in Bangkok do not currently pose a risk of transmitting AIV to humans. However, monitoring of AIV in UFPs is necessary for disease control and to minimize the possibility of influenza outbreaks.