An innovative modification of the nutrient medium formulation for the isolation and differentiation of enterobacteria

In laboratory conditions, the modified nutrient differential diagnostic medium Drigalski agar with lactose is recommended to be used for cultivation (isolation) and differentiation of enterobacteria of the Enterobacteriaceae family. The differentiation of enterobacteria on a modified medium is carried out according to their ability to ferment lactose, mannitol, glucose, sucrose, gelatin and form hydrogen sulfide. The environment can also be used for conducting sanitary and microbiological studies of environmental objects. The environment can be used to perform the ONPG test. In the course of preparing the modified Drigalski agar for operation in laboratory conditions, we recommend using the medium according to one of the options: when one of the carbohydrates is added, the medium is poured into single-section reusable or disposable petri dishes; when two carbohydrates are added, the medium is poured into two-section reusable or disposable petri dishes; when a complex of carbohydrates lactose + mannitol and glucose + sucrose is added, the medium is poured into two-section reusable or disposable petri dishes; when using all four drives separately, the medium is dispensed into single-compartment reusable or disposable petri dishes. We recommend preparing modified Drigalski agar at a plant for the production of ready-made culture media with filling the medium in two-section petri dishes (complex of carbohydrates lactose + mannitol in one section, glucose + sucrose in another section), or with filling the medium in four-section petri dishes (with each carbohydrate in separate section).

Isolasi Dan Karakterisasi Bakteri Selulolitik Biopori Sebagai Upaya Awal Percepatan Proses Pengomposan

The purpose of this study was to obtain cellulolytic bacterial isolates isolated from leaf litter in absorption holes biopori FMIPA Unesa and obtain the most optimal cellulolytic bacterial isolates in cellulose degradation. This research was an observational study and the data were analyzed descriptively. Stages of the study began with bacterial isolation, cellulolytic ability testing, and characterization of cellulolytic bacterial isolates. Bacterial isolation was carried out by the pour plate method, isolation was carried out by the streak plate method, cellulolytic testing was carried out using Carboxy Methyl Cellulose media which was given Congo red 1%. While the isolation characterization was done morphologically, physiologically, and biochemically. The results obtained 15 isolates of cellulolytic bacteria that were tested for their ability to degrade cellulose. Cellulolytic test results showed that 6 isolates, namely BS1, BS7, BS10, BS11, BS14, and BS15 had a cellulolytic index of 0.8, 0.8, 0.8, 0.8, 0.8, 0.8. and 1. Isolates BS15 is the most optimal isolate in cellulose degradation with characteristics of the punctiform colony, yellow pigmentation, entire edge, convex elevation, optical opaque and smooth surface, produces catalase enzymes, is non-motile and can ferment in glucose and starch but cannot ferment lactose and also a Gram-negative

Comparative assessment of sanitary and epidemic importance of indicator coliform indices of drinking water quality

The used methodology of the scientific substantiation of indicators is in the establishment of the conformity of laws of vital activity of indicator and pathogenic microorganisms in the real conditions of the action of the complex of factors, including disinfecting agents. In the one water sample simultaneously there were determined both the general indicator (GICB), thermotolerant (TTCB), glucose positive (GPCB) coliform bacteria, E.coli. On the base of long-term research in the various regions of the Russian Federation, as well with bearing in mind the analysis of domestic and foreign data, comparing the water quality and the incidence of intestinal infections in population it is recommended to use the index of determination of the total number glucose positive coliform bacteria (GPCB), which brings together a much broader range of bacteria of the Enterobacteriaceae family in comparison with total coliform bacteria (TCB) and thermotolerant coliform bacteria (TTCB) and warrants the absence in the test volume of water as an indicator lactose positive (E.coli, TCB, TTCB) and pathogens (salmonella) and potentially pathogenic bacteria which do not ferment lactose. Proposed index of GPCB is shown to allow to assess epidemiological risks not only more accurate, but also more efficiently without increasing the cost performance of bacteriological research.

Prevalence and toxicity characterization of Bacillus cereus in food products from Poland

The prevalence of Bacillus cereus in a total of 585 samples of food products (herbs and spices, breakfast cereals, pasta, rice, infant formulas, pasteurized milk, fresh acid and acid/rennet cheeses, mold cheeses and ripening rennet cheeses) marketed in Poland was investigated. The potential of 1022 selected isolates of B. cereus to hydrolyze casein, starch and tributyrin, to ferment lactose, to grow at 7 C/10 days, to produce Nhe and Hbl toxin and to possess the ces gene was verified. B. cereus was found in 38.8% of the analyzed samples, reaching levels from 0.3 to 3.8 log CFU g-1 or mL-1. From the 1022 isolates, 48.8%, 36.0%, 98.9%, 80.0% and 25.0% were capable of fermenting lactose, producing amylase, protease, lipase and growing at 7 C/10 days, respectively, indicating spoilage potentiality. The occurrence of toxigenic B. cereus strains in all tested market products, both of plant (55.8% Hbl(+), 70.7% Nhe(+) and 1.7% ces(+) isolates) and animal origin (84.9% Hbl(+), 82.7% Nhe(+) and 0.9% ces(+) isolates) indicates the possible risk of foodborne infections/intoxications that occur as a result of the possibility of the development of B. cereus in favorable conditions and consumption of these products.

Ethanol Production from Cheese Whey and Expired Milk by the Brown Rot Fungus Neolentinus lepideus

The basidiomycete brown rot fungus Neolentinus lepideus is capable of assimilating and fermenting lactose to ethanol with a conversion yield comparable to those of lactose-fermenting yeasts. The ability of the fungus to ferment lactose is not influenced by the addition of glucose or calcium. Therefore, N. lepideus may be useful in ethanol production from materials composed mainly of lactose, such as cheese whey or expired cow’s milk. Whey is a by-product of cheese manufacturing, and approximately 50% of the total worldwide production of whey is normally disposed of without being utilized. We found that N. lepideus produced ethanol directly from cheese whey with a yield of 0.35 g of ethanol per gram of lactose consumed, and it also fermented expired milk containing lactose, protein, and fat with a similar yield. Our findings revealed that the naturally occurring basidiomycete fungus possesses a unique ability to produce ethanol from cheese whey and expired milk. Thus, N. lepideus may be useful in facilitating ethanol production from dairy wastes in a cost-effective and environmentally friendly manner.

IMPROVEMENT OF THE CONTENT OF THE DRIGALSKI LACTOSE AGAR NUTRIENT MEDIUM

The purpose of the study is to improve the mix formulation of the Drigalski Lactose Agar breeding ground, produced by AppliChem, and aimed at enterobacteria isolation and differentiation. Development of a new mix formulation for the Drigalski Lactose Agar breeding ground, efficient assessment of cultivation of enterobacteria on its improved base and other breeding grounds used in the laboratory practice by the authors was the task of the study. The im-proved agar Drigalsky differential medium with lactose is recommended for cultivation (isolation) of different enter-obacteria of Enterobacteriaceae family.Differentiation of enterobacteria on improved medium is carried out accord-ing to their ability to ferment lactose, mannitol, glucose, sucrose, gelatin and form hydrogen sulfide. The medium can also be used for sanitary and microbiological examination of environmental objects.The medium can be used also to conduct the ONPG test. The efficiency of cultivation of enterobacteria isolated from various animal species on the most frequently used differential diagnostic medium, including new formulation of the Drigalski Lactose Agar, ranged from 16.28 ± 1.44 to 42.18 ± 4.12 hours. Enterobacteria isolated from farm and wild animals formed colo-nies on improved Drygalsky agar with lactose during 24 hours, and enterobacteria isolated from zoo animals within 25-31 hours.

Studies on Lactic Acid Bacteria Isolate Sr 13 From Bali Cattle Gastric

Lactic acid bacteria (LAB) is a generic term for bacteria that ferment lactose and produce lactic acid as its main product. In general, lactic acid bacteria belonging to Gram positive bacteria, negative catalase, does not form spores, have no cytochrome, aerotolerant, anaerobic to microaerophilic, require complex nutrients such as amino acids, vitamins (B1, B6, B12 and biotin), purine, pyrimidine. This study aims to determine the species of lactic acid bacteria (LAB) from isolate SR13 isolated from rumen liquid of bali cattle. The identification was started by cultivation of isolate on de Man, Rogosa, Sharpe (MRS) medium with anaerobic condition, confirmation of isolates by Gram staining and catalase test, and finally identificion of species by using conventional test and 50CH API test kit. The results of study showed, the isolate of LAB SR 13 was detected asPediococcus/Enterococcus, moreover, identification by using 50CH Api test kit showed as Pediococcus pentosaceus 2

Isolation and identification of bacteria from tracheas and lungs of buffaloes in Dinajpur

The aim of the present study was the isolation and identification of bacteria from trachea and lung of slaughtered buffaloes. A total of 160 swab samples were collected from tracheas (80) and lungs (80) freshly slaughtered buffeloes from the slaughter houses of Dinajpur Sadar, Dinajpur, Bangladesh, during the period from June 2011 to February 2012. Among them, 9 tracheas (out of 80 samples) and 30 lungs (out of 80 samples) showed visible lesions. Bacterial isolates were identified based on their growth, morphological and biochemical characteristics. The most frequent (5%) bacterial isolate in tracheas was Staphylococcus spp. Pasteurella haemolytica and Staphylococcus spp. were isolated from different types of lung lesions in a frequency of 5% and 16.25%, respectively. P. haemolytica showed ?- haemolysis on blood agar and did not ferment lactose and dulcitol whereas dextrose, manitol and maltose were fermented with the production of acid. This investigation would be helpful for veterinarian for the detection, treatment and control of tracheal and lung diseases of buffaloes. DOI: http://dx.doi.org/10.3329/sjm.v2i1.15211 Stamford Journal of Microbiology, Vol.2(1) 2012: 31-33

Isolation and characterization of enterohaemorrhagic Escherichia coli O157[ratio ]H7 from cattle in Belgium and Poland

EHEC O157 were isolated from faeces of Belgian and Polish beef slaughter cattle. In Belgium, 1281 faecal samples were analysed by immunomagnetic separation [IMS] after enrichment in buffered peptone water from June 1998 till July 1999. Eighty-one samples (6.3%) were positive for E. coli O157. Phage type 8 was most frequently found. Bulls between 1 and 2 years old, slaughtered in September and October were most frequently found positive. Atypical biochemical features were observed in some isolates: 22 (27%) isolates were urease positive and 1 (1.2%) isolate was unable to ferment lactose. In Poland, 551 faecal samples, taken from January 1999 till December 1999, were examined using exactly the same techniques. Four faecal samples (0.7%) were positive for O157 EHEC, yielding seven phage type 8 isolates. All positive samples were from cattle younger than 2 years. Positive samples occurred in August, September and October.