Lab #3 Report. Isolation of bacteria from environment

LAB Report #3 Introduction: In this lab we have focus on Isolation of bacteria from environment. Microorganisms are found throughout the environment: in the air and water; on the surface of any object such as clothes, walls, furniture; in soil and dust; and on and in our own bodies (skin and mucous membranes). In order to demonstrate the ubiquity and diversity of microbes in the environment, samples from immediate areas of the environment and/or from your body will be obtained and cultured. Materials: 4 sterile cotton swab, sterile water in test tube, 4 agar plates and 2 blood agar plates, wax pencil and labels.

Procedure: Appropriately label the cover of each plate as indicated in lab. 1. Determine 2 sampling sources, one from your body and one from the surrounding environment. 2. For the first agar plate, for sampling from air, remove the lids from the plate and allow it to sit uncovered for 15 minutes. 1. For second agar plate, open the “stick” end of the sterile cotton swabs to avoid contamination of the swab. Deep the swab in to the sterile water and collect a dust form the corner of the table by swab and rub the swab over the entire surface of the Petri dish without going back over areas you have already swabbed. . For the third agar plate, divide the plate in two different parts like washed and unwashed finger tip and swipe on each side of plate, see the difference between them. 4. For the forth agar plate, divide it into the four equal part and tested four different place for bacterial grow. In first part, remove the sterile cotton swab from the package and immerse it in the sterile water and take the bacteria from forearm and swipe the swab on first part.

For second part, again take the sterile cotton swab and immerse it in sterile water, and take the bacteria from back of ear and rub on the second part. For third part, again take the sterile cotton swab and immerse it in sterile water, and take the bacteria from handle of microscope and swipe on the third part. For last part, again take the sterile cotton swab and deep in to the sterile water, and take the bacteria from toilet sit and swipe on the forth part. 5. For the fifth slide, we take blood agar plate and drawing line in central part of the plate.

For one part used for kiss on that part and second part used for licked on that part for bacteria grow. 6. For last, we take another blood agar plate and we had to cough on this agar plate. Leave all agar plates in the incubator for 1 week to grow bacteria. Discussion: After one week, I was able to observe my Petri plates, which were filled with bacteria. The first plate had few yellow color colonies. That shows bacterial growth. Air was contaminant. For second plate, it had huge yellowish and few brownish color colonies and clear halos around them.

Dust also had bactria. For third plate, on unwashed part had more yellowish color tiny spots and on washed part had few whitish color tiny spot. Washed had few bacteria that may be from the water while unwashed hand had more bacterial contamination. For forth agar plate, first part had more yellowish color spots, second part had more brownish color spot, third part had no bacterial colonies and forth part had only three yellowish color colonies. That show microscope handle is not bacterial contaminant while all other object is contaminant with bacteria.

For the first blood agar plate, for the side that was kissed had huge brownish color spot and there were clear halos around it, and on other side that was licked had brownish color line. Bacteria also present in both sample. For the second blood agar plate, there is no discoloration in the plate so I think there have not bacterial growth in the Petri dish. Conclusion: In this lab we have focus on mainly “ Isolation of bacteria from environment “ and to observe the growth of bacteria in favorable condition and observation of the color and shape of the bacterial colony.

Bacteria are found in a wide variety of environments—in or on animals and plants, in water, in soil, in air, or on rock. Generally, they are contributors to the environment, decaying nutrients and recycling the minerals (for use by plants and other organisms). Bacteria are both metabolically diverse as well as structurally diverse. As I have learned we carry bacteria when we are in perfect health as well when we are sick. From this lab we have learned that bacteria are present everywhere but we can achieve healthy life by hygiene.