Magnesium is a metal; nobody can eat it directly. You can buy magnesium, but you cannot eat the metal magnesium. Iron is metal, we need iron for our blood cells, but nobodynobody can eat iron straight. We must take iron salts such as iron sulfate, iron citrate, iron gluconate, iron oxide, etc. Magnesium oxide has various applications, such as an adsorbent for toxic chemical agents, photocatalysts, refractories, and so on. It is widely used in clinical applications, and even nano-magnesium oxide has powerful antibacterial effects you can't imagine.

Magnesium oxide is one of many magnesium salts used clinically; other salts utilized are hydroxide, sulfate, carbonate, citrate, and trisilicate; magnesium oxide is only administered orally. The oxide is converted to hydroxide in water; therefore, its properties are very similar to those of magnesium hydroxide. The anion attached to the magnesium can affect the pharmacokinetics and the delivery of the elemental magnesium to the target site, Ranade and Somberg. Magnesium oxide acts as an antacid or as an osmotic laxative and can be used to correct hypomagnesemia. It is converted to sodium hydrogen carbonate (NaHCO3) and magnesium carbonate (MgCO3) by gastric and pancreatic juice and exerts its effect as a salt laxative.

MgO nanoparticles (MgO) can inhibit Gram-positive and Gram-negative bacteria. MgO nanoparticles interact with bacterial cells and cause cell membrane leakage, inducing oxidative stress, mainly due to the production of reactive oxygen species (ROS), which leads to cell death. Biosynthesized MgO NPs at a low concentration are less toxic nanoparticles to human cells. Reported the antimicrobial potency of MgO NPs against a broad spectrum of pathogenic microorganisms such as Escherichia coli, Pseudomonas aeruginos, Staphylococcus epidermidis, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus (MRSA). The MgO NPs were more effective against Gram-negative than Gram-positive bacteria, depending on the cell wall composition. MgO NPs can be used to produce infection-free medical devices and implants. MgO NPs from endophytic Streptomyces coelicolor were found effective against multidrug-resistant pathogens agents, including Shigella flexneri, Staphylococcus aureus, Streptococcus pneumonia, and Klebsiella pneumonia.