Avatar for Sourav Pan

Sourav Pan

Founder of Biology Notes Online, Biology & Microbiology Educator, M.Sc. in Microbiology
Expertise
Microbiology, Immunology, Cell Biology, Molecular Biology, Genetics, Biotechnology, Biochemistry, Botany, Zoology
Education
University of Calcutta
Profile Last Updated: August 10, 2026

Sourav Pan is the founder and sole author of Biology Notes Online. He holds a Bachelor of Science (B.Sc.) degree and an M.Sc. in Microbiology from the University of Calcutta. He creates educational resources covering microbiology, immunology, biotechnology, genetics, cell biology, botany, zoology, and other life-science subjects.

His goal is to make complex biological concepts easier to understand through well-structured, student-friendly articles based on academic textbooks, peer-reviewed research, and authoritative scientific sources. In addition to writing new content, he regularly reviews and updates articles to improve their accuracy, clarity, and educational value.

MacConkey Agar – Composition, Uses, Colony Characteristics

MacConkey Agar Composition, Uses, Colony Characteristics

MacConkey Agar is a selective and differentiated culture medium widely used to isolate of Gram-negative enteric bacteria.
It is selective since it allows for the growth of gram-negative bacteria , and differentiating the bacteria that are gram-negative based on their metabolic process of lactose.

KOH Test (Potassium hydroxide test) Principle, Procedure, Results, Uses

KOH Test (Potassium hydroxide test) Principle, Procedure, Results, Uses

A KOH pre-test is a quick, non-invasive procedure to diagnose fungal infections that affect the nails or skin.
The cells are collected from the affected region and put on a slide using an acid composed of potassium hydroxide. They are looked at under a microscope in order to determine if there are evidence of the presence of a mold.

Bile Esculin Test Principle, Procedure, Result, and application.

Bile Esculin Test Principle, Procedure, Result, and application.

Bile Esculin test The Bile Esculin test is a biological test that is used to distinguish Enterococci from Group D Streptococci from non-group D viridans group Streptococci by their capacity to hydrolyze esculin. A variety of organisms are capable hydrolyzing esculin. But only a handful of them can do it when they are surrounded by … Read more

Bacterial toxin: Definition, Types, Example.

Bacterial toxin: Definition, Types, Example.

When a microorganism starts to synthesize toxin, they are called microbial toxins, such as bacteria and fungi. There are few bacteria that can produce the most potent natural toxins such as Botulinum neurotoxins. However, the bacterial toxin has some medical importance that is why they are used in medical science and research. What Is Toxin? … Read more