Antibacterial potential of essential oils against planktonic and sessile cells of Escherichia coli isolated from diarrhea cases in swine

Escherichia coli is a pathogen associated with infections in piglets in the post-weaning phase, its pathogenicity is related to the animal's susceptibility to bacterial enterotoxins. The objective of the present study was to determine the EOs activity against E. coli strain, in the form planktonic and sessile. Although the Disc-Diffusion tests to determine the Minimum Inhibitory Concentration, do not fully corroborate with the other analyzes of this study, it was noticed bacteria inhibition. The EOs were prepared at 0.4%, 0.8% and 1.0% for tests. The tested EOs were effective against E. coli planktonic cells (p<0.05). As for the sessile cells, the most significant result was inhibition and 100% sessile cells at the concentration of 1.0% of Cymbopogon citratus EO. Although there was resistance in some treatments, the tested EOs demonstrated inhibition capacity, constituting promising alternatives for the control of E. coli, especially of planktonic cells.

The use of prebiotics to optimize gut function in pigs

Colonization of the porcine gut microbiota commences after birth; however, this development is interrupted at weaning, rendering the piglet vulnerable to enteric disease. Dietary supplementation of non-digestible oligosaccharides can contribute to the stabilization of gut homeostasis by promotion of saccharolytic bacteria, inhibition of opportunistic pathogens, bacterial metabolite production and immune regulation. Whilst traditionally fructans and galactooligosaccharides have been added to weaner pig diets, supplementation of sow’s gestation and lactation diets and oral administration of suckling piglets may exert some beneficial effects too to promote gut microbiota and (immune) function development. Oligosaccharides in sow milk act as prebiotics by specifically shaping the gut microbiota of the offspring. This chapter summarizes the current knowledge on effects of prebiotic oligosaccharides on porcine gut function and health. The modes of actions of those substances are discussed as well as aspects that need more investigation for future applications in diets for suckling piglets.

Isolation and Characterization of a Molybdenum-reducing and Carbamate-degrading Serratia sp. strain Amr-4 in soils from Egypt

Physical or chemical procedures could efficiently remove contaminants including pesticides such as carbamates from high concentrations of toxicants. Bioremediation, on the other hand, is frequently a less expensive option in the long term when used at low concentrations. Isolation of multiple toxicants removing microorganisms is the goal of bioremediation. In this paper we report on the molybdenum reduction of the bacterium and its ability to grow on the carbamates carbofuran and carbaryl as carbon sources. Both the carbamates carbofuran and carbaryl cannot support molybdenum reduction when used as the sole carbon sources. Between pH 6.0 and 6.8 and between 30 and 34 oC, the bacterium is most efficient in converting molybdate to Mo-blue. For molybdate reduction, glucose was shown to be the strongest electron donor, with maltose and sucrose coming in second and third, respectively, and d-mannitol and d-adonitol coming in last. Phosphate concentrations of 2.5 to 7.5 mM and molybdate concentrations of 20 to 30 mM are also needed. Identical to that of a decreased phosphomolybdate, the Mo-blue produced by the new Mo-reducing bacteria has an absorption spectrum similar to prior Mo-reducing bacteria. Inhibition of molybdenum reduction was 73.3, 50.1, 50.1 and 20.7 percent, respectively, by mercury, copper, silver and lead at 2 ppm. The bacterium was tentatively identified as Serratia sp. strain Amr-4 after biochemical investigation. This bacterium's ability to detoxify a variety of toxicants is highly sought after, making it a significant bioremediation agent.

Evaluation of Long–Lasting Antibacterial Properties and Cytotoxic Behavior of Functionalized Silver-Nanocellulose Composite

Materials possessing long-term antibacterial behavior and high cytotoxicity are of extreme interest in several applications, from biomedical devices to food packaging. Furthermore, for the safeguard of the human health and the environment, it is also stringent keeping in mind the need to gather good functional performances with the development of ecofriendly materials and processes. In this study, we propose a green fabrication method for the synthesis of silver nanoparticles supported on oxidized nanocellulose (ONCs), acting as both template and reducing agent. The complete structural and morphological characterization shows that well-dispersed and crystalline Ag nanoparticles of about 10–20 nm were obtained in the cellulose matrix. The antibacterial properties of Ag-nanocomposites (Ag–ONCs) were evaluated through specific Agar diffusion tests against E. coli bacteria, and the results clearly demonstrate that Ag–ONCs possess high long-lasting antibacterial behavior, retained up to 85% growth bacteria inhibition, even after 30 days of incubation. Finally, cell viability assays reveal that Ag-ONCs show a significant cytotoxicity in mouse embryonic fibroblasts.

UJI DAYA HAMBAT ANTIBAKTERI SALEP EKSTRAK ETANOL DAUN PANDAN HUTAN (Freycinetia sessiliflora Rizki.) TERHADAP PERTUMBUHAN BAKTERI Staphylococcus epidermidis

Freycinetia sessiliflora Rizki is a plant that has secondary metabolites, namely alkaloids, flavonoids, terpenoids-steroids, saponins, phenols and tannins. This study aims to determine whether there is inhibitory and concentrated ointment extract of thick pandanus leaf of the forest that can inhibit the growth of Stapylococcus epidermidis bacteria. Inhibition testing was carried out by disk diffusion method with different concentrations of 5% and 10% concentrations made 9 ointment formulas with a variety of 3 bases namely hydrocarbon base, absorbency base and water soluble base. The results of inhibitory measurements of ethanol extract ointment leaves of pandanus leaves are good or have the greatest value to the smallest inhibitory effect on the growth of Staphylococcus epidermidis bacteria with an average diameter of inhibition at F6 of 4.11 mm, F1 of 2.78 mm, F3 of 2.68 mm, F5 of 2.47 mm, F4 of 2.25 mm, F2 of 2.23 mm, F7 of 1.29, F8 of 1.13 and F9 of 0.86 mm.

Thermo-Tunable Pores and Antibiotic Gating Properties of Bovine Skin Gelatin Gels Prepared with Poly(n-isopropylacrylamide) Network

Polystyrene nanospheres (PNs) were embedded in bovine skin gelatin gels with a poly(N-isopropylacrylamide) (PNIPAAm) network, which were denoted as NGHHs, to generate thermoresponsive behavior. When 265 nm PNs were exploited to generate the pores, bovine skin gelatin extended to completely occupy the pores left by PNs below the lower critical solution temperature (LCST), forming a pore-less structure. Contrarily, above the LCST, the collapse of hydrogen bonding between bovine skin gelatin and PNIPAAm occurred, resulting in pores in the NGHH. The behavior of pore closing and opening below and above the LCST, respectively, indicates the excellent drug gating efficiency. Amoxicillin (AMX) was loaded into the NGHHs as smart antibiotic gating due to the pore closing and opening behavior. Accordingly, E. coli. and S. aureus were exploited to test the bacteria inhibition ratio (BIR) of the AMX-loaded NGHHs. BIRs of NGHH without pores were 48% to 46.7% at 25 and 37 °C, respectively, for E. coli during 12 h of incubation time. The BIRs of nanoporous NGHH could be enhanced from 61.5% to 90.4% providing a smart antibiotic gate of bovine skin gelatin gels against inflammation from infection or injury inflammation.