Arginine. Arginine, or L-arginine as it is called with its L-structure, is a semi-essential amino acid. Arginine is involved in many metabolic processes and important in the treatment of heart diseases and high blood pressure.
Layman's explanation: Nitric acid was first discovered in 1648 by a German chemist, Johann Rudolf. However, in 1901 Wilhelm Ostwald developed the Ostwald Process, which became the principle way of producing nitric acid.
What year was iron discovered in? Ancient civilizations were the first known users of the element  Iron. It is known to have been used in the year 1500 BC in Asia,  however, it is impossible to know which ci â¦ vilization was first to  acknowledge the existence of it.