Element of the Month March: Manganese
It’s familiar as an alloying component of steel, but it’s also involved in oxygen production in photosynthetic bacteria, algae and plants: Manganese.
Long before manganese was first isolated, it was already being used by humans. For example, in the form of manganese dioxide (brownstone) as a pigment for cave paintings. Later it was used as an additive in glass manufacture – here it removed the color cast from natural glass.
Discovery of manganese in pyrolusite
It was not until 1740 that the Berlin chemist and physician Johann Heinrich Pott discovered that pyrolusite not only contained iron, but also the previously unknown element, from which he eventually produced potassium permanganate – a strong oxidizing agent with a deep red-purple color.
It was not until a quarter of a century later that elemental manganese was produced by Johan Gottlieb Gahn – by reducing manganese dioxide with carbon. Hence the name manganese – it is derived from the Latin name for manganese dioxide, magnesia nigra.
Manganese is a pure element with only one stable isotope. Metallic manganese is silver-gray in color and melts at 1,247 degrees Celsius. It can be attacked by acids and water – a protective oxide layer does not form.
The mass fraction of manganese in the earth’s crust is 0.1 %. It occurs about as frequently as phosphorus and carbon. Manganese ore is mined especially in Australia, China and South Africa.
Manganese as an essential component of life
In addition to its use in alloying steel, manganese is an important element for all living things. In particular, it is found in the active site of manganese-containing superoxide dismutase, which converts reactive oxygen species such as superoxide to hydrogen peroxide and oxygen. Hydrogen peroxide is disproportionated to water and oxygen as end products by catalytic enzymes that also contain iron or manganese. Thus, manganese plays an important role in detoxification in oxygen metabolism.
Furthermore, manganese is needed in photosynthetic water oxidation, which provides oxygen to virtually all living things on earth and is considered a source of energy for plants, algae and bacteria.
A trace element that makes you happy
Compared to other trace elements, our bodies contain relatively small amounts of manganese, about 10 to 40 mg. 40 % of it is bound in our bones.
Our body needs manganese for, among other things:
- A healthy bone structure
- The formation of glucose
- The formation of melanin
- The formation of dopamine – a neurotransmitter that makes us happy.
An increased need for manganese is found in people who eat mainly processed carbohydrates, with increased alcohol consumption, stress and when taking iron supplements. With a balanced diet, there is normally no need to worry about manganese deficiency.