Agar

Discussion: Each test is a pertinent contribution to drawing an educated conclusion. After performing the gram staining and observing which unknown culture was gram positive, a catalase test was performed. The catalase test allows lab workers to differentiate Staphylococci and Streptococci genus. The test was performed only on the gram-positive culture. Bacteria that respire by the use of oxygen, otherwise known as aerobic respiration, produce enzyme or “catalase”. This protects the bacteria…

2.5. ANTIOXIDANT STATUS 2.5.1. TLC - Semi Quantitative DPPH Assay 0.2 % DPPH solution in methanol was prepared and kept in the fridge for further use. The grid space was marked with 1.0 cm2 space on an aluminum based TLC sheet (Merck silica gel 60F254) and a stock solution of all the extracts together with the standard were prepared in methanol. A series of dilutions of the stock together with the standard were prepared ranging from 400 µL to 0.01µL for the last dilution. The grid on the TLC…

dilution in order to more accurately count and quantify the bacteria. To ensure that the three different strains of bacteria are not cross contaminated, label everything either Farm A, Farm B, or Farm C depending on what is being tested. There are six agar plates for each farm, three of the plates are tetracycline plates (which are labeled) and three are unlabeled. For the three labeled plates, mark each with their dilution which will be: 10-2 ,10-4, or 10-6; do the same for the unlabeled…

3. I chose the plate with dilution factor 10-7 to count. This was the only plate that yielded an appropriate CFU, therefore, it was the sample with the highest countable colonies. The plate with the dilution of 10-6 yielded Too Many To Count (>300) while the plates with dilution 10-8 and 10-9 yielded Too Few To Count (<30). 4.If I were to do a total count on this sample, as opposed to a viable count, the total count would be higher because it accounts for all cells, not just visible and…

L.B. Agar Lysogeny broth (LB), a nutritionally rich medium, is primarily used for the growth of bacteria. The abbreviation is commonly taken to mean Luria broth, Lennox broth, or Luria-Bertani medium. According to its creator Giuseppe Bertani, the abbreviation LB was actually intended to stand for lysogeny broth (1). The formula of the LB medium was published in 1951 and continues to be the most common media used today (2). There are several common formulas of LB. Although they are different,…

barely had any yellow growth leading to the difficulty of finding the result of oxidation. The next test, Bacitracin Susceptibility, was the next test on key that helped lead to the identification of the unknown. For this procedure, you grab a Blood Agar plate, and then streak the plate with a flamed loop containing your unknown. After the plate is streaked, you will then ask your instructor to place antibacterial discs throughout the plate. These antibacterial discs, after growth, will show the…

parents to create healthier, stronger, and more beautiful babies. Just because it can be done does that mean it should? Despite the major benefit of designing babies across the world, there are many problems that this new technology allows. Nicholas Agar attempts to tackle this crisis in his article Designing Babies: Morally Permissible Ways to Modify the Human Genome However, his idea to focus on the aspect of life goals causes more problems with designing babies to pop up It is possible that…

Methods 1. Treatment of barley with endophyte. • Five types of Barley were treated with the endophyte Pseudomonas fluorescens L321. • They were innoculated with the seed coating mixture ( 4% sodium alginate and 1% skimmed milk powder) without the bacteria. The bacteria were grown up overnight in LB broth supplemented with 3% trehalose (400ml per strain) , centrifuged and then added and then resuspended in the coating mixture. • 30ml of inoculant mixture was then added to 1kg of seed in a…

For this experiment, unknown sample #12 was used. The first step in identifying any unknown bacterium is to grow a culture on a nutrient agar plate. This bacterium was also plated on a MAC plate, which is both selective for gram-negative bacteria and differential as well. On the NA plate, bright red colonies were present; on the MAC plate there was bacterial growth as well, but no color change was observed. This lack of color change on the MAC plate indicated that the bacteria did not ferment…

Violet red bile agar is a selective medium used to identify lactose-fermenting coliforms. This medium is typically used to test dairy products and water. The medium contains lactose which acts as a carbohydrate source, bile salts and crystal violet that act as an inhibitory agent towards gram-positive microorganisms and neutral red is added to serve as a pH indicator, microorganisms lower the pH which results in the colonies turning red. Some of the organisms that grow on this medium are:…