The practise of industrial biotechnology has its roots deep in antiquity. Long before their " discovery, " microorganisms were exploited to serve the needs and desires of humans, for example to preserve milk, fruits, and vegetables, and to enhance the quality of life by producing beverages, cheeses, bread, pickled foods, and vinegar. The use of yeasts dates back to ancient days. The oldest fermentation know -how -the conversion of sugar to alcohol by yeasts -was used to make beer in Sumeria and Babylonia as early as 7000 BC . By 4000 BC, the Egyptians had discovered that carbon dioxide generated by the action of brewer ' s yeast could leaven bread. Ancient peoples are also known to have made cheese with molds and bacteria.
Another ancient product of fermentation, wine, was made in Assyria in 3500 BC and reference to wine can be found in the Book of Genesis, where it is noted that Noah consumed a bit too much of the beverage. According to the Talmud, " a man without salt and vinegar is a lost man. " In the fi eld of human health, vinegar has a long history of use: the Assyrians used it to treat chronic middle ear diseases, Hippocrates treated patients with it in 400 BC, and, according to the New Testament, vinegar was offered to Jesus on the cross.
The use of microorganisms in food also has a long history. In 100 BC, Ancient Rome had over 250 bakeries which were making leavened bread. As a method of preservation, milk was fermented to lactic acid to make yogurt and also converted into kefyr and koumiss using Kluyveromyces species in Asia. The use of molds to saccharify rice in the koji process dates back at least to AD 700. By the fourteenth century AD, the distillation of alcoholic spirits from fermented grain, a practise thought to have originated in China or the Middle East, was common in many parts of the world. Vinegar manufacture began in Orleans, France, at the end of the fourteenth century and the surface technique used is known as the Orleans method.
In the seventeenth century, Antonie van Leeuwenhoek, a Dutch merchant with no university training but a keen amateur interest in the construction of microscopes, turned his simple lens to the examination of water, decaying matter,