pH on Microbial growth

This video explains about the introduction to pH, importance of pH in our life, its impact on microbial growth and how to measure pH. Please comment below if you have any question.
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Script from the video:
The self ionization of water is a continuous process, when it is in pure form. In this process, when there is collision of two H 2 O molecules, they dissociate into H plus, and OH minus ions. However, you may not find free Hydrogen ions in the water. Because, the free H plus ions have tendency to attach to the H 2 O molecule to form Hydronium ion. This means, you will always find H 3 O plus or hydronium ions in water, instead of free H plus ions. So, when we say hydrogen ions, that actually refers to hydronium ions. Now, let us see What pH is all about? PH, stands for potential of hydrogen or, some may call it as power of hydrogen. PH can be defined as, measurement of hydrogen ion concentration in a solution. Or, mathematically it can be defined as negative logarithm of hydrogen ion concentration. This formula is used to calculate PH of any solution if we know the molar hydrogen ion concentration of that particular solution. Remember that, PH is applied only to aqueous solutions. That means, where there is water there is PH. PH was first described by Sorensen in 1909. PH reveals the acidity or basicity of water. The PH scale ranges from 0 to 14, where the value 7 indicates the neutral PH. PH less than 7 indicate acidic conditions, and greater than 7 indicate basic or alkaline. In other words, PH is about calculating the free hydronium ions and free hydroxyl ions in a given solution. A solution with more H plus ions is acidic, and gives a PH value less than 7. Similarly, a solution with more OH minus ions is basic and gives a value greater than 7.
Certain reactions in our body require certain value of PH. Anything higher or lower value may cause damage. For example, if too much of Hydrochloric acid is produced in the stomach, the patient will be advised to take antacids like Magnesium hydroxide in order to neutralize the excess PH. In the same way, plants cannot grow if there is continuous rising and falling of PH of soil. Animals in the river cannot survive when acid rains fall on the river.
Similarly, PH plays an important role on microbial growth. There were cases, where microbes did not show growth in the absence of right PH conditions, even they were supplied with all the required nutrients. The PH value where a microbe can grow its best is called the optimum PH. Most bacteria grow best at a PH value near to 7. Which means most bacteria are neutrophiles. Some bacteria can grow at a PH range between 3 and 4. These are called acidophiles. Alkaliphiles are the bacteria that can tolerate PH between 8 and 11.
As we know, the bacterial cell consists of several protein molecules, lipids and nucleic acids. And the cell hosts several bio chemical reactions. All these activities are regulated when there is optimum PH. In lower PH conditions, the increased hydrogen ions break the weak hydrogen bonds of protein side chains, and finally change the shape of the protein. When a protein is not in its original shape, it cannot perform its routine function. And ultimately, the bacteria cannot survive.
There are two methods to measure PH in a microbiology lab. The first one is, using PH paper. The PH paper changes its colour when it is dipped in to a solution.This colour change is based on acidity and basicity of the sample solution. Later, the colour of the paper will be compared with the colour chart provided along with the paper. What is the reason for these papers to change colour? These papers are coated with a pigment called “Flavin”, which is extracted from Red cabbage. Flavin has ability to change colour, when it comes in contact with an acid or base. This method will not provide the exact PH value. However, this will provide a value which is closer to the actual PH value. And the other method to measure PH, that gives you an accurate value is, using a PH meter.

[@kavitha124]

Nice video👍. Please make more such videos.

[@sonumaji369]

👍👍👍

[@rafaeljedidiascanoramos4407]

Hi good afternoon , could You please🙏 tell me what áre the references for the vídeo ,like a book or articles?

[@MicrobiologyMantra]

Referred both articles and books.

[@Quotila0]

Which app do you use sir? For whiteboard animation?

[@MicrobiologyMantra]

VideoScribe

[@Quotila0]

@@MicrobiologyMantra the Paid version sir?

[@MicrobiologyMantra]

Poulami Dutta Yes

[@moghaddamshojaeenodeh1048]

usefull video dear

[@MicrobiologyMantra]

Moghaddam Shojaee Nodeh thank you