Page 42 - Curriculum Visions Dynamic Book

Sulphur for life
Sulphur originally came from gases in volcanic eruptions. It is now an essential nutrient in almost all living things. Much of the sulphur in living things is recycled between generations, a process called the sulphur cycle.
Sulphur-based medicines were among the first to deal with microbial and bacterial infections and are still widely used.
The poisonous properties of some sulphur compounds are also used to help prevent infections and to preserve foods.
Preservatives
Sulphites are used widely for food preservation. They have a wide range of actions. They may kill off fungi and bacteria, preventing decay; they may stop oxygen reacting with foodstuffs, another source of decay.
Sulphites may also be used to clean vessels in which food may be placed. This is the reason,
for example, that sulphite is added to water and then used to sterilise beer and wine vessels both in factories and in amateur beer and wine making.
Sulphites are also able to stop the natural decay processes that cause food to become discoloured. For this reason their use has been restricted
so that food cannot be stored and treated with sulphites to make it look fresher than it is.
Sulphur dioxide gas is also used as a preservative. Sulphur dioxide and sulphites both work by taking oxygen from the air, preventing microorganisms from getting the oxygen they need to live, and by creating a mildly acid environment in which organisms cannot survive.
 Sulphur drugs
Sulphur compounds have been used in the treatment
of many illnesses since ancient times. For example, brimstone and treacle was a traditional “catch-all” remedy.
Modern sulphur medicines include antibacterial drugs such as sulphonamides. They work by destroying the enzyme that is needed for the growth of bacterial cells.
Sulphur and pesticides
A pest is any life-form that causes illness and discomfort to people, or affects their food supplies or gardens.
Pesticides (named from the Latin suffix cide, which means to kill)
are chemicals that are designed
to control these pests, whether they be plants or animals. From
the writings of the ancient Greek, Homer, we can tell that as long ago as 1000 BC, ancient civilisations were aware of the pesticide properties of sulphur.
Both the Chinese and Greeks knew about the lethal combination of sulphur and arsenic. Another of the old pesticides was Bordeaux mixture, a mixture of copper sulphate and lime. It still is used to combat fungi and to repel insects.
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