Peptone water

Swab transportation tryptone saline, peptone water, enriched buffered gelatine, buffered saline, buffered gelatine, and brain-heart infusion are generally recommended media that may be used for swab transportation. For RCS + testing agar strip TC (BIOTEST) or M air T air sampler for level I is used. 

Bioburden loading levels were determined by a membrane filtration procedure prior to washing and also after the spiking to confirm that the desired challenge level was achieved. Following the cleaning cycle, the same procedure was used to evaluate residual bioburden. To recover the residual contaminants, sterile peptone water USP is used to rinse the entire inner surface of each vial. Results are reported as CFU per vial. 

These included peptone water (bacteriological peptone, Oxoid 1.0%, Analar NaCl 0.5%, pH 12-1 A), nutrient broth (Oxoid), and Mueller-Hinton broth (Oxoid). 

The homogenized livers and spleens of the autopsied animals were diluted ten-fold in 4.5 ml sterile peptone water and the blood samples were tested in undiluted condition. Prior to inoculation, the plates containing solid medium... 

Drug Dose (Pg/g) Challenge 0.95 x 109 CFU in 0.05 ml peptone water No. of animals Tested Died Type of expt. 

The presence/absence procedure was based on the ISO method for the detection of Salmonella (ISO 6579) which is summarised as follows (1) pre-enrichment in Buffered Peptone water (incubation time (18 2) h at (37 1)°C) and (2) selective enrichment in broth of own choice (incubation time and temperature according to own procedure). The detailed procedure is described elsewhere [37]. Each laboratory determined the presence or absence of Salmonella in 50 capsules. Four of these individually identified capsules were negative control capsules. The numbers of these capsules were unknown to the laboratories at the time of analysis. For the presence/absence procedure, all capsules showing typical colonies on the isolation agar were subjected to a confirmation for Salmonella. At least two colonies per capsule were used for this confirmation. All colonies (>1000 colonies) tested by the laboratories gave a positive Salmonella identification. The type of confirmation test used is described elsewhere [37]. 

In order to valuate the effects of the treatments, each inoculated sample was diluted in peptoned water and 0.1 of the dilution was plated in Palcam agar according to the ISO 11290-2 method. The enrichment method (ISO II290-I) was used in order to assess the presence of L. monocytogenes in a 25 g sample. 

The plate counts at To were estimated by diluting the neat broth culture 1 in 10 with Neutralised Peptone Water (NPW) containing per L 1.0 g Bacteriological Peptone (Oxoid, L37), 8.8 g Sodium Chloride (May Baker), 3.0 g Amisol 910 (Degussa) and 30.0 g Tween 80 (BDH, 560234H) and then decimally with Phosphate Buffered Saline (Oxoid). For biocide treated samples 1 mL was diluted in 9 mL of NPW, mixed and allowed to stand for 5 min (for neutralisation of the biocide). The solution in NPW was diluted decimally (0.1 mL in 0.9 mL) in PBS. Appropriate dilutions (0.1 mL) were plated out on Tryptone Soya Agar Plates (bioMerieux) and incubated at 37 °C for 24 h. 

S. aureus Peptone water (0.1% w/v) 12—20kV cm, 60 pulses, bipolar exponential decay pulses... 

Perez, M.C.P., Aliaga, D.R., Bemat, C.F., Enguidanos, M.R., and Lopez, A.M. 2007. Inactivation of Enterobacter sakazakii by pulsed electric field in buffered peptone water and infant formula milk. International Dairy Journal 17 1441-1449. 

A number of different media are available and failure to standardise the tests causes confusion. Peptones in the medium break down to form alkali and if the carbohydrate is metabolised to form acid, then the acid reaction is only seen if the acid is predominant. Therefore a medium high in peptone may mask a weak acid reaction. Different indicators are also used, bromothymol blue changes colour at pH 6.0 whereas bromocresol purple changes at pH 5.0. Peptone water is commonly used in the UK. Some aerobes such as Pseudomonas give unreliable results on a peptone medium and need to be tested on medium containing ammonium sulfate as a nitrogen source. 

Enrichment media similar to selective media but are designed to increase the number of desired microorganisms to a detectable level without stimulating the rest of the bacterial popnlation. When some special nntrients such as blood or serum, egg or meat pieces are added to basal media, the latter are termed enriched media. It favonrs the multiplication of a particular species of bacteria by incorporating special substances, which selectively favour its growth or inhibit the growth of competitors, e.g., selenite broth, alkaline peptone water. Blood agar, Loeffler s serum media. 

Sugar media a standard media used for biochemical tests and contains 1 % sngar in peptone water along with an indicator (Andrade s indicator). A small tube (Durham s fermentation tube) is kept inverted within the large tube containing the sugar media. Upon the production of acid by bacteria... 

In the case of probiotic microencapsulation, particles were broken down in serial dilutions with warm dilutant (peptone water, sodium citrate solution, and sodium chloride solution), for the quantification of viable cells in the system. For this specific active ingredient, as they are live microorganisms, heating cannot be too high so as to damage or kill the bacteria. Therefore, it is necessary to choose a matrix that does not have a high melting point. 

The antimicrobial activity of the fibers was tested against three cormncm strams of bacteria, i.e., Candida albicans, Ste hylococcus aureus and Pseudomonas pyocyanea. The bacteria were suspended in 0.5% peptone water with the bactoia concentration at about 1.5xl0 to 1.5x10 cfii/rrd. 35 ml 0.5% peptone water were measured into lOQml conical flasks and to each of ftiem wme added 2.5ml of the bactraia suspoision, with the bacteria concentration in the conical flask controlled at between 1x10 and 1x10 ... 

Dilution blank A sterilized solution consisting of 0.1% w/v peptone water used to dilute samples that contain large numbers of viable microorganisms. Samples are normally serially diluted (1 10, 1 100, 1 1000, 1 10,000, etc.) prior to plating using solidified agar. 

Lactose peptone water 35°C-37°C 0.5°C Gas formation in Durham tubes [70]... 

Peleusball (Pipettierball) safety pipet filler, safety pipet ball Peptidbindung peptide bond, peptide linkage Peptonwasser peptone water Perameisensaure performic acid... 

Peptisator, Plastikator peptone water Peptonwasser percentage Prozentsatz, prozentualer Anted perchloric acid Perchlorsaure percolate... 

The master culture is stored at 4 C. from this, submaster cultures are prepared weekly. Transfers are made daily into peptone-water inoculum medium and incubated at 37 C. for 24 hours. 

The turbidity of the 24 hour inoculum culture in peptone water is determined, and the number of cells is calculated by means of a curve showing the correlation between turbidity and number of cells. 

In each assay, 11 g of sample were combined with 99 ml of 0.1% peptone water which contained 0.01% tween 80. This mixture was shaken vigorously for two minutes. Serial dilutions (1 10) of samples were prepared, and 100 pi of each dilution were added to separate Petri dishes. Duplicate samples were surfaced plated in each previously-prepared, mycological media and dried at 26°C for one hour. 

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