Biomedical Importance: The human body contains a tiny 20 milligrams of manganese, mostly in the bones and metabolically active organs such as liver, kidneys, and pancreas.In plasma it is carried by a protein called Transmanganin.
In certain industries inhalation poisoning by manganese occurs and produce asthenia, anorexia, impotence, leg cramps, speech disturbances; psychotic symptoms and Parkinosonian syndrome may also be seen.
This mineral is widely distributed in the food. It sources include
- Animal Sources: These include beef, kidney, liver and oysters etc.
- Plant Sources: These include carrots, blackberries, lettuce, pineapple, nuts, cabbage, green peas, spinach, avocado, honey and lots of other food stuff.
Manganese though trace mineral still performs various important functions in our body including;
- Manganese acts as a cofactor for many enzymes that facilitate dozens of different metabolic process. For example, manganese metalloenzymes assist in urea synthesis, the conversion of pyruvate to a TCA cycle compound, and the prevention of lipid per oxidation by free radicals.
- It takes part in oxidative phosphorylation and metabolism of fatty acids, cholesterol and mucoploysacchride metabolism. It is involved in reactions catalyzed by diamine oxidase, pyruvate carboxylase and mitochondrial super oxide dismutase.
- It has a probable role in hemoglobin formation.
- Manganese is found to reduce the symptoms produced by the arthritis.
- It decreases glucose level of blood while increases the glycogen storage,
Its absorption is decreased due to high intake of phosphorous and calcium and it is excreted through the bile
Manganese requirements are low, and many plant foods contain significant amounts of this trace mineral, so deficiencies are rare. As is true of other trace minerals, however, dietary factors such as phytates inhibit its absorption. In addition, high intakes of iron and calcium limit manganese absorption, so people who use supplements of these minerals regularly may experience depressed manganese status.
Clinical Symptoms of Deficiency
- Abnormalities in the skeleton systems of human.
- There occur increase risk of cancer in case of its extreme deficiency
- The metabolism of lips and fats get disturbed as well as impairment occurs in the production of glycoprotein.
- Glucose levels of blood also become impaired.
All these result from abnormalities in the synthesis of mucopolysaccharide due to deficiency of manganese in the body.
Toxicity is more likely to occur from an environment contaminated with manganese than from dietary intake. Miners who inhale large quantities of manganese dust on the job over prolonged periods show symptoms of a brain disease, along with abnormalities of appearance and behavior such as involuntary type of laughing, blurring of vision, impotency, tremors of the hands, mask like expression on the face and the gait abnormalities.