Thiamine, as thiamine hydrochloride or thiamine mononitrate, is available from numerous sources as oral capsules, liquids, and tablets under various names. Thiamine hy-drochloride is also available in injectable form. Thiamine is also available as a component of numerous multivitamin preparations. Thiamine mononitrate is more stable than the hydrochloride in the dry state and is less hygroscopic.
The discovery of the vitamin we now call riboflavin developed from an early work with vitamin B before the knowledge that it was more than one vitamin. The reader is referred to the history of vitamin B1 because the histories are identical until the discovery that vitamin B was actually two vitamins leading to the designation of vitamin B1 and vitamin B2. The discovery of vitamin B2 was also complicated by the inconsistent experimental results seen among researchers as they focused on the dermatological effects of vitamin B2-deficient diets. The conflicting results were eventually found to be due, in part, to deficiencies in study animals not just of vitamin B2, but also vitamin B3 (niacin), the cause of human forms of pellagra, and/or vitamin B6 (pyridoxine), another cause of dermatitis. Likewise, treatments with vitamin B2 were inconsistent because the early sources of this vitamin contained other B vitamins. Vitamin B2 was eventually isolated from egg whites in 1933146 and produced synthetically in 1935.147 The name riboflavine was officially accepted in 1960106; although the term was in common use before then. In 1966, IUPAC138 changed it to riboflavin, which is in common use today.
Riboflavin is synthesized by all green plants and by most bacteria and fungi. Therefore, riboflavin is found, at least in small amounts, in most foods. Foods that are naturally high in riboflavin include milk and other dairy products, meat, eggs, fatty fish, and dark green vegetables. Fortified cereals have become an important source of riboflavin in the western diet including the United States.
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If you suffer with asthma, you will no doubt be familiar with the uncomfortable sensations as your bronchial tubes begin to narrow and your muscles around them start to tighten. A sticky mucus known as phlegm begins to produce and increase within your bronchial tubes and you begin to wheeze, cough and struggle to breathe.