Colony observation of bacteria, actinomycetes, yeasts, molds and bacterial colony preparation experiments
Colony observation of bacteria, actinomycetes, yeasts, molds and bacterial colony preparation experiments
Colony morphology refers to a certain microorganisms in a certain medium from a single organism formed by the group form. Bacteria, actinomycetes, yeasts and molds, each type of microorganisms in certain culture conditions to form colonies have certain relative characteristics, the use of observation of these characteristics, to distinguish between the major types of microorganisms and the initial identification, identification of microorganisms, the method is simple and fast, in scientific research and production practice is often used.
Operation method
Bacterial colony preparation
Principle
Blood culture medium is rich in nutrients and viscosity to culture bacteria. Colonies grown on this medium are very viscous when fixed, and can be firmly attached to slides or coverslips, making it easy for preparation and observation. In addition, blood culture medium is a good medium for preserving strains of bacteria, so the colony preparation made by this medium can be preserved for a longer period of time.
Materials and Instruments
Nitrogen-Fixing Bacteria, Bacillus subtilis, Streptomyces griseus, Saccharomyces cerevisiae, Staphylococcus albicans. Move 1. Observe individual colony characterization of Nitrogen-fixing Bacterium round brown, Bacillus subtilis, Streptomyces griseus, Saccharomyces cerevisiae, and Penicillium glabrum, and record the results as described in Experiment 1 Colony Characterization. For more product details, please visit Aladdin Scientific website.
Bouin's fixative Crystalline violet solution Peptone agar medium Alcohol
Alcohol
2. Preparation of blood agar medium:
(1) Ingredients pH 7.6 meat paste peptone agar medium 10 ml, sterile defibrinated sheep blood (or rabbit blood) 1 ml.
(2) Dissolve the meat paste peptone agar medium by heating.
(3) When it cools down to 45℃, add 1 ml of sterile defibrinated sheep blood into the culture medium by aseptic operation, and shake immediately to mix the blood and agar medium well.
(4) Pour quickly and aseptically into the plate to make a blood agar plate, taking care not to create air bubbles.
(5) Place at 37°C overnight and use if sterile growth.
(6) Remove the sterile plate for streaking and inoculation to isolate single colonies. To keep the surface of the agar intact, inoculate with a round-tipped smooth glass rod, taking care not to scratch the agar. After inoculation, inverted to 37 ℃ greenhouse culture, the next day to observe the results. If individual colonies appear, the next experiment can be carried out.
3. Bacterial colony preparation
(1) Bacterial colony imprinting choose a smaller individual colony, with a knife around the colony of about 10 ~ 15 mm square agar cut off, this agar block on the side of the colonies face down, gently placed on the coverslip, and then together with the agar block of the coverslip will be carefully placed in Bouin's fixative for about 1 hour until the agar completely white and then removed, will be carefully peeled off the agar, peeling the care not to damage the colonies, so that only the colonies left attached to the coverslip. The agar should be peeled off carefully, taking care not to damage the colonies, leaving only the colonies attached to the coverslip.
(2) Gently rinse the coverslip with colonies attached with a fine stream of water.
(3) Stain with 0.01% crystal violet staining solution for 3 minutes and then wash with water and blot dry.
(4) Dehydration The coverslips were placed in alcohol from low to high concentrations (35%, 50%, 60%, 70%, 80%, 95%, 100%) for 5 minutes each, but immersed in 100% alcohol for 15 minutes.
(5) Clearly remove the dehydrated coverslip and place it back into xylene for 2 minutes.
(6) Seal the coverslip by removing it from the xylene and swabbing the xylene from around the colony with soft paper. Immediately add a small drop of Canada Latex to the center of a clean slide, quickly invert the coverslip and gently place it on the slide so that the Canada Latex spreads all over the coverslip, taking care not to produce air bubbles, and if there are bubbles that is, gently press them out. Observe the colony characteristics with a low magnification microscope. Wait for the latex to dry completely, one or two days after the wooden box for preservation.
4. ResultsCharacterize the observed microbial colonies in the table below. 