Agar is a polysaccharide extracted from plants, mainly derived from marine algae. While bacteriological agar powder is a commonly used medium in microbiology experiments, its composition includes a variety of elements, such as Na, K, Ca, Mg, Pb, Cd, Cr, P, etc. Na and K elements play an important role in the growth and metabolism of bacteria, such as maintaining the osmotic balance and potential difference inside and outside the cell. Ca and Mg are important components of bacterial bones and cell walls, and play an important role in the growth, differentiation and morphology maintenance of bacteria. Heavy metal elements such as Pb, Cd, Cr may have toxic effects on bacteria, affecting their growth and function. And P elements, as phosphorus sources, are essential for the growth and development of bacteria. Therefore, understanding the content of these elements in bacteriological agar powder can help to better control the experimental conditions and ensure the accuracy and reliability of the experimental results. Attachment download