The appearance of bacterial colonies an

The proliferation of bacteria more especially in damaged tomatoes could be considered to be more harmful when such contaminated tomatoes are consumed in improperly cooked food [ 2 ]. In addition to known reference strains for N. Turn the Petri dish on end.

Whilst Klebsiella oxytoca Theoretically, one colony contains the descendants clones of a single bacterial cell that had taken up the plasmid. This is a difficult procedure. What are Fungal Colonies Fungal colonies are either a mass of cells of unicellular fungi or fungal hyphae of multicellular fungi.

Gram stain of H. Aspirate 1 ml with a sterile syringe and needle from the blood culture bottle and transfer 0. The results of this study cannot be generalized to all tomatoes sold in Ghana as variations in seasons, handling, harvesting, and postharvesting practices are different in many regions in Ghana.

That showiness doesn't come from pigments, but rather the microscopic internal structure of the colonies, which reflect light at different wavelengths to create, to our eyes, a certain color.

However, Nocardia grown under suboptimal conditions sometimes appear uniformly Gram-negative; therefore, negative Gram-staining cannot be used to rule out Nocardia.

Arrangement and Size The arrangement and size of an E.

Observing bacteria in a petri dish

A similar study also revealed high levels of Staphylococcus sp. Form Bacterial colonies are circular or irregular while fungal colonies are filamentous or rhizoid. Growth of Salmonella ser.

Mycelium and spore colours also greatly differ among the fungal species. When dry, examine the stained smear under a microscope with X oil immersion objective. You can identify E. Varying levels of antibiotic resistance bacteria amongst tomatoes sold at various markets were found. Proper smear preparation using the CSF sediment should produce a monolayer of organisms sufficiently dense for easy visualization but thin enough to reveal morphological characteristics.

The trace organic material found in tap water provides sufficient nutrients to support growth. It is assumed that one bacterial colony arises from a single bacterial cell and is multiplied by binary fission into many bacteria. It is rich in nutrients, vitamins, dietary fibres, and phytochemicals [ 3 — 5 ].

Growth and identification of Nocardia Nocardia may be difficult to culture in clinical microbiology laboratories Nocardia species are classically gram-positive, strictly aerobic, filamentous, branching, weakly acid-fast bacilli.

They have a defined margin as well. Fungal colonies grow comparatively slowly on agar media. Fungal colony morphologies are different between different types of fungi. The presence of bacteria with antibiotic resistance associated with tomatoes sampled in this study highlights the potential risk of tomatoes to consumers.

This technique is much faster and easier to master.


Do not use povidone-iodine on the rubber stopper as it may be carried into the medium by the passing needle, thus inhibiting the growth of bacteria.

In most developing countries, microbial infestation of tomatoes can occur during the harvesting period, postharvesting, handling, storage, transportation, and processing by customers [ 910 ]. Introduction Tomato Lycopersicon esculentum is a perishable vegetable widely cultivated and consumed worldwide [ 12 ].

Gently blot the slide using bibulous paper or a clean paper towel. Materials 1 mixed-culture in tryptic soy broth TSB tube containing Staphylococcus xylosus, Serratia marsescens, and Escherichia. In Nigeria, Wogu and Ofuase [ 14 ] isolated Bacillus subtils, Klebsiella aerogenes, Pseudomonas aeruginosa, Salmonella typhi, Proteus mirabilis, and Staphylococcus aureus from spoilt tomatoes in Benin City.

Contamination might have been caused by poor sanitation, improper handling or transportation from the farms to the markets. After incubation, the colonies of the different culture media were examined and recorded based on the shape, colour, border, texture, and general appearance of individual bacterial colonies on each plate, and single representative colony was Gram stained.

Gram staining was done to reveal the characteristic group and arrangement of the cells. 1a. Size – The size of the colony can be a useful characteristic for identification. The diameter of a representative colony may be measured. Tiny colonies are referred to as punctiform.

1b. Surface – Bacterial colonies are frequently shiny and smooth in appearance.

Difference Between Bacterial and Fungal Colonies

Other surface descriptions might be: veined, rough, dull, wrinkled (or. Nine obviously different colonies are numbered: some colony types recur in various areas of the plate (note # 3 and # 4). Not only are pigment differences seen, but also size, edge, pattern, opacity, and shine.

Two circles have been drawn around merging colonies, where the species of the 2 colonies are different. Nov 15,  · Cultural characteristics of bacterial colonies?

If a colony of bacteria growing on 5% sheeps blood agar has a ground-glass appearance what does that mean in terms of the margin (is it lobate, undulate, entire, filiform, or curled) and the whole colony shape (is it circular, irregular, filamentous, or rhizoid)?Status: Resolved.

The zone of inhibition is a parameter measured in the Calibrated Disk Sensititvity test, to determine if bacteria are resistant or susceptible to antibiotics at set concentrations. The zone of inhibition refers to an area on an agar plate around a.

Bacterial colonies are usually have a smooth and creamy appearance, but can have various colors and textures. Fungi are always furry; they are white in the beginning, and then turn dark green, black, or brown as they form spores.

The appearance of bacterial colonies an
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Bacterial colonies