2.1 Material N,N-Dimethyl formamide (DMF), 2,2-Azobisisobutyronitrile (AIBN), Silver nitrate (AgNO3) and Methanol were purchased from the lobachemie Pvt. Ltd. (India). Styrene monomer was procured from the sigma-Aldrich. Co. The solvents DMF and methanol were distilled for purification. Other chemicals were used as obtained. 2.2 Preparation of polystyrene (PS) Polystyrene prepared by free radical polymerization of styrene monomer. Styrene (1 mole) was taken in a round bottom flask (RBF) fitted with a reflux condenser. DMF was used as a solvent and AIBN (0.5% w/w of total monomer) as free radical initiator .The reaction was carried out at 70±2° C for 6 hour with constant stirring. After completion of the process it was cooled to room temperature and resultant polymer solution was poured in the large amount of methanol with stirring when polymer precipitated out. It was filtered and washed with methanol. The polymer was purified by repeated precipitation using methanol from solution in DMF and then it dried. 2.3 Preparation of PS …show more content…
All microorganism cultures were prepared from their respective slants. Cultures were grown over 24 hour at 37 °C and optical density was adjusted to 0.1, which corresponds to 108 CFU (colony forming unit)/ ml at 600 nm. About 100 µL bacteria were added to 100 ml of a nutrient broth solution to give bacteria concentration about 108 CFU/ ml. 4.2 Well diffusion method This method was employed to essay antimicrobial activity of pure PS nanofiber and Ag nano particle doped PS composite nanofibers. The bacterial suspension (100 µL 108 CFU) was spread uniformly on the nutrient agar plate and 50 µL solution of each of PS and Ag/ PS prepared in DMSO was loaded in each well on nutrient agar plate The plate was then put in incubator for 24 hour at 37 °C to record inhibition zone [38]. 4.3 Viable cell counting
Human beings are hosts for many bacterial species that colonize our skin as their natural flora. The skin acts as a superior barrier and first line of defense against bacterial infections. When they do occur, these infections are mild and easily treatable; however some can become very serious and even life-threatening. Staphylococcus aureus and Streptococcus pyogenes are uncommon bacteria, but they are responsible for a wide variety of bacterial pyodermas [1]. In some cases, the host for bacterial infections can become contagious to others.
We made mother culture of our strain. We took 3 test tubes and added 3 ml ammonium sulphate broth and autoclaved them. Then labelled them as +ve control, -ve control and test. In +ve control, we added 0.1 gram soil, in –ve control,we didn’t add anything and in 3rd test tube we added 0.1ml from mother culture.
In this experiment, we are testing “Antibacterial Activity and Mechanism of Silver Nanoparticles on E. Coli.” We will examine three things throughout this experiment; Will Silver Nanoparticles will cause the E. Coli to grow? How much silver nanoparticles are needed to cause growth?, and How much Silver Nanoparticles to destroy the E. Coli? We hypothesis that about 10ug/ml of the silver nanoparticles will cause the E. Coli to grow and about 45ug/ml Silver Nanoparticles to destroy the bacteria.
Inducing Prodigiosin Transposon mutagenesis in Serratia Marcescens Introduction Serratia Marcescens is an opportunistic pathogen, mainly of healthcare facilities but can also be found in many diverse environments. Serratia is a gram negative bacteria which can give it innate resistance to certain antibiotics, especially those that target peptidoglycan cell wall synthesis, due to its outer membrane. In an environment with different microorganisms competing for food Serratia holds a component that gives it another selective advantage. The bacteria contains a red pigment called prodigiosin, that has antibacterial, antifungal, and even antiprotozoal activity.
The six bacteria used in this lab were, Citrobacter freundii, Bacillus subtillis, Enterobacter aerogenes, Staphylococcus epidermis, Enterococcus durans, and Escherichia coli. Citrobacter freundii is a Gram-negative rod shape bacteria. The MSA plate will grow Citrobacter freundii, Bacillus subtillis, Enterobacter aerogenes and will have a yellow color change while Staphylococcus epidermis will not grow nor have a color change to yellow. The MacConkey agar will have growth with Escherichia coli, Enterococcus durans, but not Staphylococcus epidermis and Bacillus subtilis since it is a Gram-positive.
Experiment 2 Report Scaffold (Substitution Reactions, Purification, and Identification) Purpose/Introduction 1. A Sn2 reaction was conducted; this involved benzyl bromide, sodium hydroxide, an unknown compound and ethanol through reflux technique, mel-temp recordings, recrystallization, and analysis of TLC plates. 2. There was one unknown compound in the reaction that was later discovered after a series of techniques described above.
Apart from zebrafish work, I also purified DNA and used gel electrophoresis as a verification method, as well as prepared aseptic microbial cultures, growth media preparation and aseptic buffer
5 mm size filter paper disks were prepared using whatmann filter paper no.1 saturated with 10 μl of complexes and placed in petri dishes containing LB (Luria Bertini) agar media inoculated with E. coli, Bacillus subtilis and Staphylococcus aureus separately. The petri dishes were incubated at 25±0.2°C and the zone of inhibitions were noticed after 48h. The plates were observed and the diameters of the inhibition zones (in mm) were deliberated, and compared with standard antibacterial drug
5.2. POVIDONE78, 79: Nonproprietary Names: BP: Povidone, USP: Povidone Synonyms: E1201; Kollidon; Plasdone; poly[1-(2-oxo-1-pyrrolidinyl)ethylene]; polyvidone; polyvinylpyrrolidone; PVP; 1-vinyl-2-pyrrolidinone polymer. Chemical Name and CAS Registry Number: 1-Ethenyl-2-pyrrolidinone homopolymer [9003-39-8] Empirical Formula and Molecular Weight: (C6H9NO)n 2500–3 000 000
The DEAE CL-6b gel was washed twice with 0.5m Hcl, twice with 0.5m Naoh and twice with PB ph6.0 before utilization. For DEAE 1ml gel every 1ml serum was utilized. In the wake of blending for 1 hour at 200c the suspension was centrifuged at 4500g for 25 minutes. The supernatant was thought by Ammonium sulfate precipitation and pellet was broken up in refined water and the ensuing arrangement was dialyzed against PBS ph7.2 to evacuate Ammonium sulfate and conformed to the first volume with yhe same cushion (Hong et.al., 1994). 2)
As many as 1 mL hydrogel preparations added in 1 mL of growth medium with stratified so that dilution dilution series made were 50%, 25%, 12.5%, 6.25%, 3.12%, 1.56%, 0.78%, 0.39%, 0.02%, and 0.01% by volume end of the tube was 1 mL. Then as much as 1 mL of bacterial culture equal Mc. Farland 0.5 added into the test tubes so that the final volume of the tubes were 2 mL. All test tubes were incubated at 37 °C for 18 h. Turbidity test observed in the media and determined MIC value preparations. Tube with negative results or does not indicate the presence of growth, then conducted subculture with solid growth media each bacteria as test assertion MIC value chloramphenicol preparations hydrogel. As many as 20 mL of growth medium was prepared and then given solids have zones for the variation of concentration with the method MIC macrodillution preparations showed the absence of growth.
Lysergic acid diethylamide is a natural substance synthesized from the parasitic rye fungus, Claviceps purpurea2. Albert Hofmann, a natural products chemist at the Sandoz AG Pharmaceutical Company, synthesized it in 1938 while experimenting with pharmaceutical uses for ergot2,4. He intended for this series known as LSD-25 to be used as a circulatory and respiratory stimulant. However, after minimal testing LSD-25 aroused no special interest in the pharmacologists and physicians. Testing was then discontinued and not worked with until his curiosity struck him 5 years later.
However using bacteriostatic agent can have a reverse effect on bacterial selection of which attributes to damage of bacteria in stress condition. To avoid this effect in FDA BAM, the agent added after 4hrs of incubation to allow the injured cells to recover and grow in media, but in ISO 11290 at first step of enrichment, the half concentration of agent is added. In both media the buffering capacity of media is very high and leads to enhanced cell growth and
Copper and silver nanoparticles have gained considerable attention due to their significant and broad spectrum bioactivity. Currently these nanoparticles find utility as antimicrobial formulations, biomedical and surgical devices. Silver ions have been used as an antibacterial component in the coatings of devices employed in medical procedures. Silver and copper in the form of nano particles is also known to exhibit strong bactericidal effects on gram positive and gram negative
From all nanomaterials with antibacterial properties, metallic nanoparticles provide the best results. Several types of NPs, including various Molecules of 30 metal and metal oxides, have been developed and evaluated by different research groups; examples include silver (Ag), gold (Au), Ag oxide (Ag2O), zinc oxide (ZnO), titanium dioxide (TiO2), calcium oxide (CaO), copper oxide (CuO), magnesium oxide (MgO), and silicon dioxide