Microbiology of food and animal feeding stuffs. Horizontal method for the detection and enumeration of coliforms. Most probable number technique

Water is the main source for life and also the most severe substance caused by pollution. The mandatory parameters for determining microbiological quality of drinking water are total non-fecal Coliform bacteria and Coliform fecal (Escherichia coli). Coliform bacteria are a group of microorganisms commonly used as indicators, where these bacteria can be a signal to determine whether a water source has been contaminated by bacteria or not, while fecal Coliform bacteria are indicator bacteria polluting pathogenic bacteria originating from human feces and warm-blooded animals (mammals) . The water inspection method in this study uses the MPN (Most Probable Number) method which consists of 3 tests, namely, the presumption test, the affirmation test, and the reinforcement test. The results showed that of 15 drinking water samples 8 samples were tested positive for Coliform bacteria with the highest total bacterial value of sample number 1, 15 (210/100 ml), while 7 other samples were negative. From 8 positive Coliform samples only 1 sample was stated to be negative fecal Coliform bacteria and 7 other samples were positive for Coliform fecal bacteria with the highest total bacterial value of sample number 1 (210/100 ml).

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Cemaran Eshericia coli dalam makanan laut yang beredar di pasar tradisional Kota Pontian

Jurnal Kesehatan Khatulistiwa ◽

10.26418/jurkeswa.v1i1.42974 ◽

2015 ◽

Vol 1 (1) ◽

pp. 44

Author(s):

Rafika Sari ◽

Pratiwi Apridamayanti

Keyword(s):

Most Probable Number ◽

Probable Number

Latar Belakang: Makanan laut merupakan salah satu jenis makanan yang banyak dikonsumsi oleh masyarakat selain sebagai komoditi ekspor. Mengkonsumsi makanan laut yang telah terkontaminasi bakteri hidup atau toksin yang dihasilkannya dapat menyebabkan keracunan makanan. Tujuan penelitian ini adalah untuk mengetahui adanya kontaminasi bakteri koliform E.coli sebagai indikator pencemaran pada makanan laut dan memberikan informasi kelayakan dan keamanan konsumsi dari makanan laut di dua pasar tradisional terbesar di daerah Pontianak. Metode: Sampel yang digunakan adalah ikan, sotong dan udang. Penelitian terhadap sampel dilakukan menggunakan uji Most Probable Number (MPN) yang dilengkapi dengan uji biokimia untuk mengidentifikasi jenis bakteri pada sampel melalui penanaman bakteri pada media agar Lactose Broth (LB) dan Briliant Green Lactose Bile Broth (BGLB). Hasil: Hasil penelitian menunjukkan bakteri koliform E.coli terdeteksi pada 100% sampel dengan nilai MPN yang tidak memenuhi kriteria kelayakan konsumsi, yakni >3/g. Kesimpulan: Makanan yang ada tidak memenuhi kriteria kelayakan konsumsi.

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The Occurrence of Legionella Bacteria in Cooling Towers in South Africa

Water Science & Technology ◽

10.2166/wst.1991.0047 ◽

1991 ◽

Vol 24 (2) ◽

pp. 149-152 ◽

Cited By ~ 1

Author(s):

N. A. Grabow ◽

E. J. Pienaar ◽

R. Kfir

Keyword(s):

South Africa ◽

Most Probable Number ◽

Cooling Towers ◽

Probable Number ◽

Service Water ◽

Standard Plate ◽

Viable Bacteria ◽

Plate Counts ◽

High Level ◽

Biocide Treatment

A total of 510 service water samples from cooling towers throughout South Africa were analysed for the presence of Legionella bacteria. Legionella was detected using an immuno-labelling technique based on the most probable number principle. Only cultural (viable) bacteria were counted. Legionellae were found in most of the samples tested. However, in only 4% of the samples a high level of legionellae was recorded. No correlation was found between the numbers of legionellae and those of standard plate counts. Biocide treatment was shown to be effective in the removal of the bacteria from cooling towers after a 3-month treatment period.

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A Most Probable Number Method for the Enumeration of Legionella Bacteria in Water

Water Science & Technology ◽

10.2166/wst.1991.0046 ◽

1991 ◽

Vol 24 (2) ◽

pp. 143-147 ◽

Cited By ~ 6

Author(s):

N. A. Grabow ◽

R. Kfir ◽

W. O. K. Grabow

Keyword(s):

Water Samples ◽

Membrane Filtration ◽

Quantitative Method ◽

Fluorescent Antibody ◽

Most Probable Number ◽

Probable Number ◽

Comparative Tests ◽

Antibody Staining ◽

Direct Fluorescent Antibody ◽

Yeast Extract Agar

A new quantitative method for the enumeration of Legionella bacteria in water is described. Appropriate tenfold serial dilutions of water samples concentrated by membrane filtration are plated in triplicate on buffered charcoal yeast extract agar. After incubation for 3 days representative smears from individual plates are tested for the presence of Legionella by direct fluorescent antibody staining. The number of positive plates in each dilution is used to calculate the Legionella count by means of conventional most probable number statistics. In comparative tests on a variety of water samples this method yielded significantly higher counts than previously used procedures.

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Persistence of Orally Administered Salmonella enterica Serovars Agona and Montevideo in Atlantic Salmon (Salmo salar L.)

Journal of Food Protection ◽

10.4315/0362-028x-68.7.1336 ◽

2005 ◽

Vol 68 (7) ◽

pp. 1336-1339 ◽

Cited By ~ 10

Author(s):

L. L. NESSE ◽

T. LØVOLD ◽

B. BERGSJØ ◽

K. NORDBY ◽

C. WALLACE ◽

...

Keyword(s):

Gastrointestinal Tract ◽

Atlantic Salmon ◽

Salmo Salar ◽

Salmonella Enterica ◽

Most Probable Number ◽

Fish Feed ◽

Internal Organs ◽

Probable Number ◽

Atlantic Salmon Salmo Salar ◽

Gastric Intubation

The objective of our experiments was to study the persistence and dissemination of orally administered Salmonella in smoltified Atlantic salmon. In experiment 1, salmon kept at 15°C were fed for 1 week with feed contaminated with 96 most-probable-number units of Salmonella Agona per 100 g of feed and then starved for 2 weeks. Samples were taken from the gastrointestinal tract and examined for Salmonella 1, 2, 8, 9, 15, and 16 days after the feeding ended. In experiment 2, Salmonella Agona and Montevideo were separately mixed with feed and administered by gastric intubation. Each fish received 1.0 × 108, 1.0 × 106, or 1.0 × 104 CFU. The different groups were kept in parallel at 5 and 15°C and observed for 4 weeks. Every week, three fish in each group were sacrificed, and samples were taken from the skin, the pooled internal organs, the muscle, and the gastrointestinal tract and examined for the presence of Salmonella. The results from the two experiments showed that the persistence of Salmonella in the fish was highly dependent on the dose administered. Salmonella was not recovered from any of the fish that were fed for 1 week with the lowest concentration of Salmonella. In the fish given the highest dose of Salmonella, bacteria persisted for at least 4 weeks in the gastrointestinal tract as well as, to some extent, the internal organs. The present study shows that under practical conditions in Norway, the risk of Salmonella in fish feed being passed on to the consumer of the fish is negligible.

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