PRODUCTS

SULPHUR

Sulphur is used as a fungicide in agriculture.
Sulphur is applied in the production of sulfuric acid (H₂SO₄), a key industrial chemical.
Sulphur is used in cosmetics, especially for acne treatments and skin care.

CAS number: 7704-34-9
EC number: 231-722-6
Molecular Formula: S₈
Molecular Weight: 256.52 g/mol

SYNONYMS:
Sulphur, Brimstone, Flowers of Sulfur, Sulfur powder, Sulfure, Sulfuric acid precursor, Sulfur dust

Sulfur (also spelled sulphur in British English) is a chemical element; it has symbol S and atomic number 16.
Sulphur is abundant, multivalent and nonmetallic. Under normal conditions, Sulphur atoms form cyclic octatomic molecules with the chemical formula S8.

Elemental Sulphur is a bright yellow, crystalline solid at room temperature.
Sulphur is the tenth most abundant element by mass in the universe and the fifth most common on Earth.
Though sometimes found in pure, native form, Sulphur on Earth usually occurs as sulfide and sulfate minerals.

Being abundant in native form, Sulphur was known in ancient times, being mentioned for its uses in ancient India, ancient Greece, China, and ancient Egypt.
Historically and in literature Sulphur is also called brimstone, which means "burning stone".

Almost all elemental Sulphur is produced as a byproduct of removing Sulphur-containing contaminants from natural gas and petroleum.
The greatest commercial use of the element is the production of sulfuric acid for sulfate and phosphate fertilizers, and other chemical processes.

Sulphur is used in matches, insecticides, and fungicides.
Many Sulphur compounds are odoriferous, and the smells of odorized natural gas, skunk scent, bad breath, grapefruit, and garlic are due to organosulfur compounds.

Hydrogen sulfide gives the characteristic odor to rotting eggs and other biological processes.
Sulphur is an essential element for all life, almost always in the form of organosulphur compounds or metal sulfides.
Amino acids (two proteinogenic: cysteine and methionine, and many other non-coded: cystine, taurine, etc.) and two vitamins (biotin and thiamine) are organosulfur compounds crucial for life.

Many cofactors also contain Sulphur, including glutathione, and iron–Sulphur proteins.
Disulfides, S–S bonds, confer mechanical strength and insolubility of the (among others) protein keratin, found in outer skin, hair, and feathers.

Sulphur is one of the core chemical elements needed for biochemical functioning and is an elemental macronutrient for all living organisms.
Sulphur is a multivalent non-metal, abundant, tasteless and and odorless.
In its native form sulphur is a yellow crystalline solid.

In nature Sulphur occurs as the pure element or as sulfide and sulfate minerals.
Although sulphur is infamous for its smell, frequently compare to rotten eggs, that odor is actually characteristic of hydrogen sulphide (H2S).
The crystallography of sulphur is complex.

Depending on the specific conditions, sulphur allotropes form several distinct crystal structures.
Sulphur (S), nonmetallic chemical element belonging to the oxygen group (Group 16 [VIa] of the periodic table), one of the most reactive of the elements.

Pure Sulphur is a tasteless, odourless, brittle solid that is pale yellow in colour, a poor conductor of electricity, and insoluble in water.
Sulphur reacts with all metals except gold and platinum, forming sulfides; it also forms compounds with several nonmetallic elements.
Millions of tons of Sulphur are produced each year, mostly for the manufacture of sulfuric acid, which is widely used in industry.

Sulphur is also present in molybdenum cofactor.
In cosmic abundance, Sulphur ranks ninth among the elements, accounting for only one atom of every 20,000–30,000.
Sulphur occurs in the uncombined state as well as in combination with other elements in rocks and minerals that are widely distributed, although it is classified among the minor constituents of Earth’s crust, in which its proportion is estimated to be between 0.03 and 0.06 percent.

On the basis of the finding that certain meteorites contain about 12 percent sulfur, Sulphur has been suggested that deeper layers of Earth contain a much larger proportion.
Seawater contains about 0.09 percent Sulphur in the form of sulfate.

In underground deposits of very pure Sulphur that are present in domelike geologic structures, the Sulphur is believed to have been formed by the action of bacteria upon the mineral anhydrite, in which Sulphur is combined with oxygen and calcium.
Deposits of Sulphur in volcanic regions probably originated from gaseous hydrogen sulfide generated below the surface of Earth and transformed into Sulphur by reaction with the oxygen in the air.

Sulphur is a non-metallic chemical element identified by the letter S.
Sulphur is a valuable commodity and integral component of the world economy used to manufacture numerous products including fertilizers and other chemicals.

Sulphur also is a vital nutrient for crops, animals and people.
Sulphur occurs naturally in the environment and is the thirteenth most abundant element in the earth's crust.
Sulphur can be mined in its elemental form, though this production has reduced significantly in recent years.

Since early in the 20th Century, the Frasch process has been used as a method to extract sulphur from underground deposits, when it displaced traditional mining principally in Sicily.
Most of the world's sulphur was obtained this way until the late 20th century, when sulphur's recovery from petroleum and gas sources (recovered sulphur) became more commonplace.

As of 2011, the only operating Frasch mines worldwide are in Poland and since 2010 in Mexico.
The last mine operating in the United States closed in 2000. A Frasch mine in Iraq closed in 2003.
Sulphur that is mined or recovered from oil and gas production is known as brimstone, or elemental sulphur.

Sulphur produced as a by-product of ferrous and non-ferrous metal smelting is produced in the form of sulphuric acid.
A smaller volume is produced as sulphur dioxide, which is also emitted from petroleum products used in vehicles and at some power plants.
Plants absorb sulphur from the soil in sulphate form.

Sulphur is an ecological product.
Sulphur's main applications include those related to agriculture, due to its activity as fungicide, acaricide, nutritional product and soil conditioner, as well as those related to industry, such as tyres, the rubber industry, animal feed and pyrotechnics.

Sulphur (S) is an essential nutrient required by all crops for optimum production.
Plants take up and use S in the sulphate (SO4-S) form which, like nitrate (NO3-N), is very mobile in the soil and is prone to leaching in wet soil conditions, particularly in sandy soils.

Sulphur deficiencies are becoming increasingly common in Alberta.
Deficiencies can be easily corrected with fertilizers containing sulphate (SO4).
Generally, S is the third most limiting soil nutrient in cereal, oilseed and forage crop production in Alberta.

It is third only to nitrogen (N) and phosphorus (P) in fertilizer use in Alberta.
Oilseed crops, particularly canola and forage crops, have a higher S requirement than cereal crops.
Sulphur is required in the development of fertile canola flowers and must be present for good nodule development on legume forages such as alfalfa and pulse crop roots such as pea and faba bean.

Sulphur is now the second most important nutrient
Sulphur is a fundamental ingredient of life on earth.
Sulphur is present in all crops and plays an important role in plant metabolism.

Sulphur is essential for the formation of plant proteins, amino acids, some vitamins and enzymes.
Most compound fertilisers containing sulphur also contain nitrogen, highlighting the close link between these two elements.
Sulphur is part of an enzyme required for nitrogen uptake and lack of it can severely hamper nitrogen metabolism.

Together with nitrogen, sulphur enables the formations of amino acids needed for protein synthesis.
Sulphur is found in fatty acids and vitamins and has an important impact on quality and taste or smell of crops.
Sulphur is also essentially involved in photosynthesis, overall energy metabolism and carbohydrate production.

Sulphur is a classical product which provides effective control of powdery mildew in Fruits and vegetables simultaneously provides nutrition to crops.
Sulphur is an element that exists in nature and can be found in soil, plants, foods, and water.

Some proteins contain Sulphur in the form of amino acids.
Sulphur is an essential nutrient for plants.
Sulphur can kill insects, mites, fungi, and rodents.

Sulphur has been registered for use in pesticide products in the United States since the 1920s.
Sulphur (S) is the fourth macronutrient, but ranks as the third most limiting nutrient on the Prairies.
Sulphur deficiency in western Canada was first identified in 1927 on Gray Wooded soils in Alberta.

Canola is more sensitive than cereals to sulphur deficiency and frequently responds to fertilizer sulphur addition.
Therefore, pay equal attention to nitrogen, phosphorus and sulphur.
Sulphur occurs naturally near volcanoes.

Native sulphur occurs naturally as massive deposits in Texas and Louisiana in the USA.
Many sulphide minerals are known: pyrite and marcaiste are iron sulphide ; stibnite is antimony sulphide; galena is lead sulphide; cinnabar is mercury sulphide and sphalerite is zinc sulphide.

Other, more important, sulphide ores are chalcopyrite, bornite, penlandite, millerite and molybdenite.
The chief source of sulphur for industry is the hydrogen sulphide of natural gas, Canada is the main producer.

USES and APPLICATIONS of SULPHUR:
Fertilizers: Sulphur is used as a key ingredient in fertilizers to promote plant growth.
Pharmaceuticals: Sulphur is incorporated into topical medicines and ointments for skin conditions.
Rubber Industry: Sulphur is used in vulcanization to improve the durability and elasticity of rubber.

Pesticides: Sulphur is used as a fungicide in agriculture.
Industrial Processes: Sulphur is applied in the production of sulfuric acid (H₂SO₄), a key industrial chemical.
Cosmetics: Sulphur is used in cosmetics, especially for acne treatments and skin care.

The major derivative of sulphur is sulphuric acid (H2SO4), one of the most important elements used as an industrial raw material.
Sulphur is also used in batteries, detergents, fungicides, manufacture of fertilizers, gun power, matches and fireworks.
Other applications of Sulphur are making corrosion-resistant concrete which has great strength and is forst resistant, for solvents and in a host of other products of the chemical and pharmaceutical industries.

-Sulphur in the environment:
Life on Earth may have been possible because of sulphur.
Conditions in the early seas were such that simple chemical reactions could have generate the range of amino acids that are the building blocks of life.

-INDUSTRIAL USES of Sulphur:
*RUBBER AND TYRE VULCANISING INDUSTRY:
Sulphur is used essential element in industrial processes

*DISINFECTION OF WINE BARRELS:
Sulphur tablets help to keep barrels in good condition and free from germs.

*ANIMAL FEED INDUSTRY:
Sulphur is a substantial contribution to the vitamins and proteins of the animal life cycle

-Sulfuric acid:
Elemental Sulphur is used mainly as a precursor to other chemicals. Approximately 85% (1989) is converted to sulfuric acid (H2SO4):
1⁄8 S8 + 3⁄2 O2 + H2O → H2SO4
In 2010, the United States produced more sulfuric acid than any other inorganic industrial chemical.

The principal use for the acid is the extraction of phosphate ores for the production of fertilizer manufacturing.
Other applications of sulfuric acid include oil refining, wastewater processing, and mineral extraction.

-Other important Sulphur chemistry:
Sulphur reacts directly with methane to give carbon disulfide, which is used to manufacture cellophane and rayon.
One of the uses of elemental Sulphur is in vulcanization of rubber, where polysulfide chains crosslink organic polymers.

Large quantities of sulfites are used to bleach paper and to preserve dried fruit.
Many surfactants and detergents (e.g. sodium lauryl sulfate) are sulfate derivatives.

Calcium sulfate, gypsum (CaSO4•2H2O) is mined on the scale of 100 million tonnes each year for use in Portland cement and fertilizers.
When silver-based photography was widespread, sodium and ammonium thiosulfate were widely used as "fixing agents".
Sulphur is a component of gunpowder ("black powder").

-Fertilizer uses of Sulphur:
Amino acids synthesized by living organisms such as methionine and cysteine contain organoSulphur groups (thioester and thiol respectively).
The antioxidant glutathione protecting many living organisms against free radicals and oxidative stress also contains organic sulfur.

Some crops such as onion and garlic also produce different organoSulphur compounds such as syn-propanethial-S-oxide responsible of lacrymal irritation (onions), or diallyl disulfide and allicin (garlic).

Sulfates, commonly found in soils and groundwaters are often a sufficient natural source of Sulphur for plants and bacteria.
Atmospheric deposition of Sulphur dioxide (SO2) is also a common artificial source (coal combustion) of Sulphur for the soils.
Under normal circumstances, in most agricultural soils, Sulphur is not a limiting nutrient for plants and microorganisms (see Liebig's barrel).

However, in some circumstances, soils can be depleted in sulfate, e.g. if this later is leached by meteoric water (rain) or if the requirements in Sulphur for some types of crops are high.
This explains that Sulphur is increasingly recognized and used as a component of fertilizers.

The most important form of Sulphur for fertilizer is calcium sulfate, commonly found in nature as the mineral gypsum (CaSO4•2H2O).
Elemental Sulphur is hydrophobic (not soluble in water) and cannot be used directly by plants.
Elemental Sulphur (ES) is sometimes mixed with bentonite to amend depleted soils for crops with high requirement in organo-sulfur.

Over time, oxidation abiotic processes with atmospheric oxygen and soil bacteria can oxidize and convert elemental Sulphur to soluble derivatives, which can then be used by microorganisms and plants.
Sulphur improves the efficiency of other essential plant nutrients, particularly nitrogen and phosphorus.

Biologically produced Sulphur particles are naturally hydrophilic due to a biopolymer coating and are easier to disperse over the land in a spray of diluted slurry, resulting in a faster uptake by plants.

The plants requirement for Sulphur equals or exceeds the requirement for phosphorus.
Sulphur is an essential nutrient for plant growth, root nodule formation of legumes, and immunity and defense systems.
Sulphur deficiency has become widespread in many countries in Europe.

Because atmospheric inputs of Sulphur continue to decrease, the deficit in the Sulphur input/output is likely to increase unless Sulphur fertilizers are used.
Atmospheric inputs of Sulphur decrease because of actions taken to limit acid rains.

-Fungicide and pesticide uses of Sulphur:
Elemental Sulphur is one of the oldest fungicides and pesticides.
"Dusting sulfur", elemental Sulphur in powdered form, is a common fungicide for grapes, strawberry, many vegetables and several other crops.

Sulphur has a good efficacy against a wide range of powdery mildew diseases as well as black spot.
In organic production, Sulphur is the most important fungicide.

Sulphur is the only fungicide used in organically farmed apple production against the main disease apple scab under colder conditions.
BioSulphur (biologically produced elemental Sulphur with hydrophilic characteristics) can also be used for these applications.

Standard-formulation dusting Sulphur is applied to crops with a Sulphur duster or from a dusting plane.
Wettable Sulphur is the commercial name for dusting Sulphur formulated with additional ingredients to make it water miscible.
Sulphur has similar applications and is used as a fungicide against mildew and other mold-related problems with plants and soil.

Elemental Sulphur powder is used as an "organic" (i.e., "green") insecticide (actually an acaricide) against ticks and mites.
A common method of application is dusting the clothing or limbs with Sulphur powder.

A diluted solution of lime Sulphur (made by combining calcium hydroxide with elemental Sulphur in water) is used as a dip for pets to destroy ringworm (fungus), mange, and other dermatoses and parasites.
Sulphur candles of almost pure Sulphur were burned to fumigate structures and wine barrels, but are now considered too toxic for residences.

-Pharmaceuticals uses of Sulphur:
Sulphur (specifically octasulfur, S8) is used in pharmaceutical skin preparations for the treatment of acne and other conditions.
Sulphur acts as a keratolytic agent and also kills bacteria, fungi, scabies mites, and other parasites.

Precipitated Sulphur and colloidal Sulphur are used, in form of lotions, creams, powders, soaps, and bath additives, for the treatment of acne vulgaris, acne rosacea, and seborrhoeic dermatitis.
Many drugs contain Sulphur.

Early examples include antibacterial sulfonamides, known as sulfa drugs.
A more recent example is mucolytic N-acetylcysteine.

Sulphur is a part of many bacterial defense molecules.
Most β-lactam antibiotics, including the penicillins, cephalosporins and monobactams contain sulfur.

-Batteries uses of Sulphur:
Due to their high energy density and the availability of sulfur, there is ongoing research in creating rechargeable lithium–Sulphur batteries.
Until now, carbonate electrolytes have caused failures in such batteries after a single cycle.

In February 2022, researchers at Drexel University have not only created a prototypical battery that lasted 4000 recharge cycles, but also found the first monoclinic gamma Sulphur that remained stable below 95 degrees Celsius.

USES AND EFFECTIVENESS OF SULPHUR:
Possibly Effective for

*Dandruff.
Sulphur is an FDA-approved ingredient used in common over-the-counter products to treat dandruff.

However, available research on its effectiveness is limited.
Some research shows that using a shampoo containing Sulphur and/or salicylic acid twice daily for 5 weeks reduces dandruff.

Shampoo containing both Sulphur and salicylic acid seems to be most effective.
Itchy skin infection caused by mites (scabies).

Applying a jelly containing Sulphur to the skin appears to be an effective treatment for scabies in most people.
Sulphur treatments are usually applied overnight for 3 to 6 nights.

But this treatment is not pleasant due to the smell.
Also, there are better and cheaper treatments available, including the drugs ivermectin and permethrin.

*Insufficient Evidence for Acne.
Sulphur is an FDA-approved ingredient used in common over-the-counter products to treat acne.

However, there is limited research available on its effectiveness.
Most products include Sulphur in combination with benzoyl peroxide, salicylic acid, or sodium sulfacetamide.

*Hay fever.
Early research shows that using a nasal spray containing homeopathic (diluted) amounts of sulfur, luffa, Galphimia glauca, and histamine for 42 days is as effective as common cromolyn sodium nasal spray.

A lung disease that makes it harder to breathe (chronic obstructive pulmonary disease or COPD).
Early research shows that breathing in the air from warm Sulphur water does not help the lungs to function in people with COPD.

*Common cold.
Early research suggests that taking a homeopathic (diluted) product containing Sulphur and German ipecac (Engystol, Heel GmbH) by mouth for up to 2 weeks during a cold helps relieve symptoms.

High levels of cholesterol or other fats (lipids) in the blood (hyperlipidemia).
Early research suggests that drinking water from a sulfurous spring three times daily for 4 weeks reduces total cholesterol, low-density lipoprotein (LDL or "bad") cholesterol, and triglyceride levels.

However, it's not clear from this study alone if Sulphur might reduce cholesterol.
A skin condition that causes redness on the face (rosacea).

Early research suggests that applying a cream containing Sulphur to the face once daily for up to 8 weeks reduces fluid-filled bumps on the face and other symptoms caused by rosacea.
Some early research shows that Sulphur cream may be as effective as the antibiotic tetracycline.

*Shortness of breath.

*Sore throat (pharyngitis).

*Symptoms of menopause.

*Lice.

*Cold sores (herpes labialis).

*Warts.
Rough, scaly skin on the scalp and face (seborrheic dermatitis).
Poison oaky, ivy, and sumac infections.

*Other conditions.
More evidence is needed to rate Sulphur for these uses.

ROLE OF SULPHUR IN CANOLA PLANTS:
Canola contains large amounts of sulphur.
Sulphur is part of structural and enzymatic components.

Sulphur is a key component of two essential amino acids (cysteine and methionine) and is needed for protein synthesis.
Chlorophyll synthesis also requires sulphur.

Both of these amino acids are also precursors for coenzymes and secondary plant substances.
Glutathione, an important antioxidant in plants and animals, is synthesized from cysteine.

Glutathione contents are higher in leaves than roots.
It’s found primarily in the chloroplasts where its anti-oxidant ability is needed to detoxify free radicals generated during photosynthesis.

Glutathione also functions as transient sulphur storage, and a precursor of phytochelatins (compounds which detoxify heavy metals in plants).
Thioredoxins, another important group of sulphur compounds related to glutathione, help activate several enzymes in carbon metabolism.

Sulphur also is part of several enzymes and coenzymes such as ferrodoxin, biotin (vitamin H), coenzyme A, urease, and thiamine (vitamin B1).
An important group of secondary plant sulphur compounds in canola are glucosinolates.

Plants contain over 100 different glucosinolate compounds.
These secondary compounds, although not well understood, probably have a number of functions.

Glucosinolates are stored in cell vacuoles, and can be broken down by an enzyme (myrosinase) to yield glucose, sulphate and volatile compounds such as isothiocyanate.

Glucosinolates contribute to defense or attractant systems for certain insects and diseases.
When plant cells are destroyed by insect feeding, glucosinolates are broken down, releasing various deterrents/attractants.

Glucosinolate levels are highest in growing points, roots, and youngest leaves, all of which are most vulnerable to insects and diseases.
The role of glucosinolates as sulphur reserves to maintain plant sulphur during periods of high demand (such as bolting, flowering, podding and seed fill) is controversial.

However, research in Europe showed that glucosinolates comprised a small sulphur pool in leaves, and under induced sulphur deficiency, sulphate (SO4-2) mobilization from storage in cell vacuoles was about 10 times greater than contributions from glucosinolates.
Sulphur is also a constituent of sulpholipids, which are membrane components.

SULPHUR UPTAKE BY CANOLA:
The main sulphur form absorbed by canola roots is sulphate.
In industrial areas, atmospheric sulphur compounds dissolved in rain can be absorbed by leaves.

However, this amount is quite small and is decreasing with better air pollution control.
Sulphate absorption is accomplished with active transport systems across membranes.

The uptake rate increases as the sulphate level increases in the soil water.
Low plant sulphur contents also increase the root uptake rate.

Negative feedback signals for sulphur uptake may be sulphate or glucosinolate levels in vacuoles, or the levels of organic sulphur compounds such as cysteine, methionine or glutathione.

Sulphate uptake faces competition from molybdenum and selenium.
Therefore, soils high in these minerals will antagonize sulphur uptake.
The sulphur level in canola plants is highest in the early seedling stage when young leaves comprise most of the dry matter.

As plants develop, the overall sulphur level declines but not as dramatically as with nitrogen.
By maturity, canola straw contains approximately 0.3 to 0.4 per cent sulphur while pod chaff contains slightly more sulphur (0.5 to 0.6 per cent).

Canola seed contains about 0.4 to 0.6 per cent sulphur.
At harvest, canola straw and pod chaff contain roughly twice as much sulphur per acre as that in the seed.

Sulphur uptake increases rapidly after germination and peaks three to four weeks after emergence.
This highlights the importance of early season sulphur availability, but also indicates that sulphur deficiency can be corrected if top dressing of ammonium sulphate occurs early enough, before the canola bolts.

There has been limited research on the complex sulphur partitioning into the various compounds of different plant parts over the growing season.
Most of the plant sulphur ends up in protein and stored sulphate.

As leaves senesce, protein sulphur is readily remobilized, while stored sulphate remobilization is slow and more limited.
Therefore, overall, sulphur has medium mobility.

SULPHUR SUPPLY FROM THE SOIL:
The organic portion of the sulphur cycle in soil is closely tied to nitrogen due to their association in protein.
Like nitrogen, the main sulphur reserve in soil is in organic matter.

Although there is considerable variability in the relative proportions or ratio of carbon, nitrogen and sulphur (C:N:S) in soil organic matter, the ratios are quite similar for each soil group.

In a study of Saskatchewan farm soils, the C:N:S ratio ranged from 58:6:1 in Brown soils, to 63:7:1 in Dark Brown, 83:8:1 in Black, 100:8:1 in Gray Black, and 129:11:1 in Gray soils.
A key component of the soil sulphur cycle for plant growth is the mineralization path.

Soil organic matter and plant residues are decomposed by soil microbes, releasing sulphate.
The sulphur mineralization rate is quite slow (much slower than nitrogen), and cannot match the uptake rate of growing plants.

Also like nitrogen, the sulphate amounts released from residues will depend on the sulphur content.
When plant residues contain more than about 0.15 per cent sulphur (C:S ratio about 300:1), there will be a net release of sulphate through mineralization.

Below 0.15 per cent sulphur, decomposition is slower and there will be immobilization of soil sulphate by soil microbes.
The ability of soil to mineralize sulphate from organic matter has been found to be independent of the total amount of carbon, nitrogen or sulphur, and of the C:N or N:S ratios in soils.

However, research has also found that the initial amounts of sulphate mineralized from soil are closely correlated with the initial amounts of nitrogen mineralized in short-term incubation.

Another important aspect of the soil sulphur cycle is the oxidation path.
In soils, sulphides, elemental sulphur and thiosulphate can be oxidized to sulphate by various soil microbes, but the main actors are bacteria from the genus Thiobacillus.

The oxidation of these inorganic sulphur compounds produces considerable sulphuric acid.
Sulphur oxidizing bacteria are most active under warm, moist, well aerated conditions.

It is the oxidizing ability of these bacteria that permits the agricultural use of elemental sulphur for crop growth.
Although sulphur reduction is shown in the soil sulphur cycle diagram, it generally is not significant in aerated agricultural soils.

In flooded soils, sulphate can be reduced by soil microbes to sulphides in a process analogous to denitrification.
However, soil microbes will utilize nitrate, iron and manganese compounds before reducing sulphate.
Although sulphur reduction is shown in the soil sulphur cycle diagram, it generally is not significant in aerated agricultural soils.

In many western Canadian soils, there is a subsoil salt (gypsum) and/or a lime (calcium carbonate) layer.
This subsoil layer contains considerable sulphate, often as co-precipitates with lime.

Although this subsoil sulphate solubility is reduced, it still can contribute to plant needs if it exists within the rooting zone.
However, the length of time that canola grows in sulphur deficient topsoil before rooting to the subsoil sulphur will affect the yield response to fertilizer sulphur.

Also, the depth to subsoil sulphur tends to vary greatly across the field.
Total sulphur amounts (organic and sulphate) generally increase from upper to lower slope positions.

In most prairie soils, sulphate is not held by organic matter and clay particles since they are both negatively charged.
Therefore, sulphate is vulnerable to leaching losses.

IMPORTANT TIPS FOR SULPHUR FERTİLİZER MANAGEMENT:
Sulphur is very important for meeting yield expectations.
Typically it is recommended to give canola at least 10 to 20 pounds per acre of sulphur, regardless of the soil test results.

Due to highly variable sulphur levels within fields, composite soil test may show sufficient levels even though large parts of the field are deficient.
Use ammonium sulphate to address sulphur needs in the year of application.

Elemental sulphur will not usually be converted to available sulphate form in time for adequate uptake in sufficient quantities in the year of application.
Ammonium sulphate (AS) should be placed away from the seed row. Save the seed row location for phosphorus fertilizer, as it provides a known early season benefit to stand establishment.

Adding AS to the seed row in addition to ammonium phosphate pushes the nitrogen levels too high for seedling safety in many cases.
An in-crop application of sulphate fertilizer can be effective at rescuing most of the crop’s yield potential if canola shows signs of deficiency and fertilizer is applied early enough to allow sufficient uptake by early flowering at the latest.

Sulphur is a chemical element that is present in all living tissues.
After calcium and phosphorus, Sulphur is the third most abundant mineral in the human body.
Sulphur is also found in garlic, onions, and broccoli.

Sulphur is applied to the skin for dandruff and an itchy skin infection caused by mites (scabies).
Sulphur is also applied to the skin for acne and skin redness (rosacea), and taken orally for many other conditions, but there is limited scientific evidence to support these uses.

HOW DOES SULPHUR WORK?
Sulphur is present in all living tissues.
Sulphur is the third most abundant mineral in the human body.
Sulphur seems to have antibacterial effects against the bacteria that cause acne.

Sulphur also might help promote the loosening and shedding of skin.
This is believed to help treat skin conditions such as seborrheic dermatitis or acne.

Sulphur is present in all living tissues.
Sulphur is the third most abundant mineral in the human body.

Sulphur seems to have antibacterial effects against the bacteria that cause acne.
Sulphur also might help promote the loosening and shedding of skin.
This is believed to help treat skin conditions such as seborrheic dermatitis or acne.

CHARACTERISTICS OF SULPHUR:
PHYSICAL PROPERTIES OF SULPHUR:
Sulphur forms several polyatomic molecules.
The best-known allotrope is octasulfur, cyclo-S8.

The point group of cyclo-S8 is D4d and Sulphur's dipole moment is 0 D.
OctaSulphur is a soft, bright-yellow solid that is odorless.
It melts at 115.21 °C (239.38 °F), and boils at 444.6 °C (832.3 °F).

At 95.2 °C (203.4 °F), below its melting temperature, cyclo-octaSulphur begins slowly changing from α-octaSulphur to the β-polymorph.
The structure of the S8 ring is virtually unchanged by this phase transition, which affects the intermolecular interactions.

Cooling molten Sulphur freezes at 119.6 °C (247.3 °F), as it predominantly consists of the β-S8 molecules.
Between its melting and boiling temperatures, octaSulphur changes its allotrope again, turning from β-octaSulphur to γ-sulfur, again accompanied by a lower density but increased viscosity due to the formation of polymers.

At higher temperatures, the viscosity decreases as depolymerization occurs.
Molten Sulphur assumes a dark red color above 200 °C (392 °F).
The density of Sulphur is about 2 g/cm3, depending on the allotrope; all of the stable allotropes are excellent electrical insulators.

Sulphur sublimes more or less between 20 °C (68 °F) and 50 °C (122 °F).[19]
Sulphur is insoluble in water but soluble in carbon disulfide and, to a lesser extent, in other nonpolar organic solvents, such as benzene and toluene.

CHEMICAL PROPERTIES OF SULPHUR:
Under normal conditions, Sulphur hydrolyzes very slowly to mainly form hydrogen sulfide and sulfuric acid:
1⁄2 S8 + 4 H2O → 3 H2S + H2SO4

The reaction involves adsorption of protons onto S8 clusters, followed by disproportionation into the reaction products.
The second, fourth and sixth ionization energies of Sulphur are 2252 kJ/mol, 4556 kJ/mol and 8495.8 kJ/mol, respectively.

The composition of reaction products of Sulphur with oxidants (and its oxidation state) depends on whether releasing of reaction energy overcomes these thresholds.
Applying catalysts and/or supply of external energy may vary sulfur's oxidation state and the composition of reaction products.

While reaction between Sulphur and oxygen under normal conditions gives Sulphur dioxide (oxidation state +4), formation of Sulphur trioxide (oxidation state +6) requires a temperature of 400–600 °C (750–1,100 °F) and presence of a catalyst.
In reactions with elements of lesser electronegativity, it reacts as an oxidant and forms sulfides, where it has oxidation state −2.

Sulphur reacts with nearly all other elements except noble gases, even with the notoriously unreactive metal iridium (yielding iridium disulfide).
Some of those reactions require elevated temperatures

ALLOTROPES OF SULPHUR:
Sulphur forms over 30 solid allotropes, more than any other element.
Besides S8, several other rings are known.
Removing one atom from the crown gives S7, which is of a deeper yellow than S8.

HPLC analysis of "elemental sulfur" reveals an equilibrium mixture of mainly S8, but with S7 and small amounts of S6.
Larger rings have been prepared, including S12 and S18.

Amorphous or "plastic" Sulphur is produced by rapid cooling of molten sulfur—for example, by pouring it into cold water.
X-ray crystallography studies show that the amorphous form may have a helical structure with eight atoms per turn.

The long coiled polymeric molecules make the brownish substance elastic, and in bulk it has the feel of crude rubber.
This form is metastable at room temperature and gradually reverts to the crystalline molecular allotrope, which is no longer elastic.
This process happens over a matter of hours to days, but can be rapidly catalyzed.

ISOTOPES OF SULPHUR:
Sulphur has 23 known isotopes, four of which are stable: 32S (94.99%±0.26%), 33S (0.75%±0.02%), 34S (4.25%±0.24%), and 36S (0.01%±0.01%).
Other than 35S, with a half-life of 87 days, the radioactive isotopes of Sulphur have half-lives less than 3 hours.

The preponderance of 32S is explained by its production in the so-called alpha-process (one of the main classes of nuclear fusion reactions) in exploding stars.

Other stable Sulphur isotopes are produced in the bypass processes related with 34Ar, and their composition depends on a type of a stellar explosion.
For example, proportionally more 33S comes from novae than from supernovae.

On the planet Earth the Sulphur isotopic composition was determined by the Sun.
Though it was assumed that the distribution of different Sulphur isotopes would be more or less equal, it has been found that proportions of the two most abundant Sulphur isotopes 32S and 34S varies in different samples.

Assaying of the isotope ratio (δ34S) in the samples suggests their chemical history, and with support of other methods, it allows to age-date the samples, estimate temperature of equilibrium between ore and water, determine pH and oxygen fugacity, identify the activity of sulfate-reducing bacteria in the time of formation of the sample, or suggest the main sources of Sulphur in ecosystems.

However, there are ongoing discussions over the real reason for the δ34S shifts, biological activity or postdeposit alteration.
For example, when sulfide minerals are precipitated, isotopic equilibration among solids and liquid may cause small differences in the δ34S values of co-genetic minerals.

The differences between minerals can be used to estimate the temperature of equilibration.
The δ13C and δ34S of coexisting carbonate minerals and sulfides can be used to determine the pH and oxygen fugacity of the ore-bearing fluid during ore formation.

Scientists measure the Sulphur isotopes of minerals in rocks and sediments to study the redox conditions in past oceans.
Sulfate-reducing bacteria in marine sediment fractionate Sulphur isotopes as they take in sulfate and produce sulfide.

Prior to the 2010s, it was thought that sulfate reduction could fractionate Sulphur isotopes up to 46 permil and fractionation larger than 46 permil recorded in sediments must be due to disproportionation of Sulphur compounds in the sediment.

This view has changed since the 2010s as experiments showed that sulfate-reducing bacteria can fractionate to 66 permil.
As substrates for disproportionation are limited by Sulphur of sulfate reduction, the isotopic effect of disproportionation should be less than 16 permil in most sedimentary settings.

In forest ecosystems, sulfate is derived mostly from the atmosphere; weathering of ore minerals and evaporites contribute some sulfur.
Sulphur with a distinctive isotopic composition has been used to identify pollution sources, and enriched Sulphur has been added as a tracer in hydrologic studies.

Differences in the natural abundances can be used in systems where there is sufficient variation in the 34S of ecosystem components.
Rocky Mountain lakes thought to be dominated by atmospheric sources of sulfate have been found to have measurably different 34S values than lakes believed to be dominated by watershed sources of sulfate.

The radioactive 35S is formed in cosmic ray spallation of the atmospheric 40Ar.
This fact may be used to verify the presence of recent (up to 1 year) atmospheric sediments in various materials.

This isotope may be obtained artificially by different ways.
In practice, the reaction 35Cl + n → 35S + p is used by irradiating potassium chloride with neutrons.

The isotope 35S is used in various sulfur-containing compounds as a radioactive tracer for many biological studies, for example, the Hershey-Chase experiment.
Because of the weak beta activity of 35S, Sulphur's compounds are relatively safe as long as they are not ingested or absorbed by the body.

HISTORY OF SULPHUR:
The history of Sulphur is part of antiquity.
The name itself probably found its way into Latin from the language of the Oscans, an ancient people who inhabited the region including Vesuvius, where Sulphur deposits are widespread.

Prehistoric humans used Sulphur as a pigment for cave painting; one of the first recorded instances of the art of medication is in the use of Sulphur as a tonic.
The combustion of Sulphur had a role in Egyptian religious ceremonials as early as 4,000 years ago.

“Fire and brimstone” references in the Bible are related to sulfur, suggesting that “hell’s fires” are fuelled by sulfur.
The beginnings of practical and industrial uses of Sulphur are credited to the Egyptians, who used Sulphur dioxide for bleaching cotton as early as 1600 bce.

Greek mythology includes Sulphur chemistry: Homer tells of Odysseus’ use of Sulphur dioxide to fumigate a chamber in which he had slain his wife’s suitors.
The use of Sulphur in explosives and fire displays dates to about 500 bce in China, and flame-producing agents used in warfare (Greek fire) were prepared with Sulphur in the Middle Ages.

Pliny the Elder in 50 ce reported a number of individual uses of Sulphur and ironically was himself killed, in all probability by Sulphur fumes, at the time of the great Vesuvius eruption (79 ce).

Sulphur was regarded by the alchemists as the principle of combustibility.
Antoine Lavoisier recognized it as an element in 1777, although it was considered by some to be a compound of hydrogen and oxygen; its elemental nature was established by the French chemists Joseph Gay-Lussac and Louis Thenard.

NATURAL OCCURRENCE AND DISTRIBUTION OF SULPHUR:
Many important metal ores are compounds of sulfur, either sulfides or sulfates.
Some important examples are galena (lead sulfide, PbS), blende (zinc sulfide, ZnS), pyrite (iron disulfide, FeS2), chalcopyrite (copper iron sulfide, CuFeS2), gypsum (calcium sulfate dihydrate, CaSO4∙2H2O) and barite (barium sulfate, BaSO4).

The sulfide ores are valued chiefly for their metal content, although a process developed in the 18th century for making sulfuric acid utilized Sulphur dioxide obtained by burning pyrite.
Coal, petroleum, and natural gas contain Sulphur compounds.

PROPERTIES OF SULPHUR:
*Allotropes:
Sulphur exists in several allotropes, with the most common being the S₈ molecule.

*Reactivity:
Sulphur reacts with metals and oxygen to form sulfides and Sulphur dioxide, respectively.

*Acidic Properties:
Sulphur, when burned in oxygen, forms Sulphur dioxide (SO₂), which is a strong acid when dissolved in water.

BENEFITS OF SULPHUR:
*Agricultural Benefits:
Sulphur in fertilizers helps to boost crop production and improve soil quality.

*Medicinal Benefits:
Sulphur is used for skin diseases such as acne, dandruff, and eczema.

*Industrial Applications:
Sulphur is vital in manufacturing products like sulfuric acid, which is widely used in many industrial processes.

NATURAL OCCURRENCE OF SULPHUR:
32S is created inside massive stars, at a depth where the temperature exceeds 2.5×109 K, by the fusion of one nucleus of silicon plus one nucleus of helium.
As this nuclear reaction is part of the alpha process that produces elements in abundance, Sulphur is the 10th most common element in the universe.

Sulfur, usually as sulfide, is present in many types of meteorites.
Ordinary chondrites contain on average 2.1% sulfur, and carbonaceous chondrites may contain as much as 6.6%.

It is normally present as troilite (FeS), but there are exceptions, with carbonaceous chondrites containing free sulfur, sulfates and other Sulphur compounds.
The distinctive colors of Jupiter's volcanic moon Io are attributed to various forms of molten, solid, and gaseous sulfur.

In July 2024, elemental Sulphur was accidentally discovered to exist on Mars after the Curiosity rover drove over and crushed a rock, revealing Sulphur crystals inside it.

Sulphur is the fifth most common element by mass in the Earth.
Elemental Sulphur can be found near hot springs and volcanic regions in many parts of the world, especially along the Pacific Ring of Fire; such volcanic deposits are mined in Indonesia, Chile, and Japan.

These deposits are polycrystalline, with the largest documented single crystal measuring 22 cm × 16 cm × 11 cm (8.7 in × 6.3 in × 4.3 in).
Historically, Sicily was a major source of Sulphur in the Industrial Revolution.

Lakes of molten Sulphur up to about 200 m (660 ft) in diameter have been found on the sea floor, associated with submarine volcanoes, at depths where the boiling point of water is higher than the melting point of sulfur.

Native Sulphur is synthesized by anaerobic bacteria acting on sulfate minerals such as gypsum in salt domes.
Significant deposits in salt domes occur along the coast of the Gulf of Mexico, and in evaporites in eastern Europe and western Asia.

Native Sulphur may be produced by geological processes alone. Fossil-based Sulphur deposits from salt domes were once the basis for commercial production in the United States, Russia, Turkmenistan, and Ukraine.
Such sources have become of secondary commercial importance, and most are no longer worked but commercial production is still carried out in the Osiek mine in Poland.

Common naturally occurring Sulphur compounds include the sulfide minerals, such as pyrite (iron sulfide), cinnabar (mercury sulfide), galena (lead sulfide), sphalerite (zinc sulfide), and stibnite (antimony sulfide); and the sulfate minerals, such as gypsum (calcium sulfate), alunite (potassium aluminium sulfate), and barite (barium sulfate).

On Earth, just as upon Jupiter's moon Io, elemental Sulphur occurs naturally in volcanic emissions, including emissions from hydrothermal vents.
The main industrial source of Sulphur has become petroleum and natural gas.

COMPOUNDS OF SULPHUR:
Common oxidation states of Sulphur range from −2 to +6.
Sulphur forms stable compounds with all elements except the noble gases.

*Electron transfer reactions
Sulphur polycations, S2+8, S2+4 and S2+19 are produced when Sulphur is reacted with oxidizing agents in a strongly acidic solution.
The colored solutions produced by dissolving Sulphur in oleum were first reported as early as 1804 by C. F. Bucholz, but the cause of the color and the structure of the polycations involved was only determined in the late 1960s.
S2+8 is deep blue, S2+4 is yellow and S2+19 is red.

Reduction of Sulphur gives various polysulfides with the formula S2−x, many of which have been obtained in crystalline form.
Illustrative is the production of sodium tetrasulfide:

4 Na + S8 → 2 Na2S4
Some of these dianions dissociate to give radical anions, such as S−3 gives the blue color of the rock lapis lazuli.

This reaction highlights a distinctive property of sulfur: its ability to catenate (bind to itself by formation of chains).
Protonation of these polysulfide anions produces the polysulfanes, H2Sx, where x = 2, 3, and 4.
Ultimately, reduction of Sulphur produces sulfide salts:

16 Na + S8 → 8 Na2S
The interconversion of these species is exploited in the sodium–Sulphur battery.

*Hydrogenation
Treatment of Sulphur with hydrogen gives hydrogen sulfide.
When dissolved in water, hydrogen sulfide is mildly acidic:

H2S ⇌ HS− + H+
Hydrogen sulfide gas and the hydrosulfide anion are extremely toxic to mammals, due to their inhibition of the oxygen-carrying capacity of hemoglobin and certain cytochromes in a manner analogous to cyanide and azide (see below, under precautions).

*Combustion
The two principal Sulphur oxides are obtained by burning sulfur:

S + O2 → SO2 (Sulphur dioxide)
2 SO2 + O2 → 2 SO3 (Sulphur trioxide)
Many other Sulphur oxides are observed including the sulfur-rich oxides include Sulphur monoxide, diSulphur monoxide, diSulphur dioxides, and higher oxides containing peroxo groups.

*Halogenation
Sulphur reacts with fluorine to give the highly reactive Sulphur tetrafluoride and the highly inert Sulphur hexafluoride.
Whereas fluorine gives S(IV) and S(VI) compounds, chlorine gives S(II) and S(I) derivatives.

Thus, Sulphur dichloride, diSulphur dichloride, and higher chlorosulfanes arise from the chlorination of sulfur.
Sulfuryl chloride and chlorosulfuric acid are derivatives of sulfuric acid; thionyl chloride (SOCl2) is a common reagent in organic synthesis.
Bromine also oxidizes Sulphur to form Sulphur dibromide and diSulphur dibromide.

*Pseudohalides
Sulphur oxidizes cyanide and sulfite to give thiocyanate and thiosulfate, respectively.

*Metal sulfides
Sulphur reacts with many metals.
Electropositive metals give polysulfide salts.
Copper, zinc, and silver are attacked by sulfur; see tarnishing.

Although many metal sulfides are known, most are prepared by high temperature reactions of the elements.
Geoscientists also study the isotopes of metal sulfides in rocks and sediment to study environmental conditions in the Earth's past.

*Organic compounds
Some of the main classes of sulfur-containing organic compounds include the following:
Thiols or mercaptans (so called because they capture mercury as chelators) are the Sulphur analogs of alcohols; treatment of thiols with base gives thiolate ions.

Thioethers are the Sulphur analogs of ethers.
Sulfonium ions have three groups attached to a cationic Sulphur center.

Dimethylsulfoniopropionate (DMSP) is one such compound, important in the marine organic Sulphur cycle.
Sulfoxides and sulfones are thioethers with one and two oxygen atoms attached to the Sulphur atom, respectively.

The simplest sulfoxide, dimethyl sulfoxide, is a common solvent; a common sulfone is sulfolane.
Sulfonic acids are used in many detergents.

Compounds with carbon–Sulphur multiple bonds are uncommon, an exception being carbon disulfide, a volatile colorless liquid that is structurally similar to carbon dioxide.

It is used as a reagent to make the polymer rayon and many organoSulphur compounds.
Unlike carbon monoxide, carbon monosulfide is stable only as an extremely dilute gas, found between solar systems.

OrganoSulphur compounds are responsible for some of the unpleasant odors of decaying organic matter.
They are widely known as the odorant in domestic natural gas, garlic odor, and skunk spray, as well as a component of bad breath odor.

Not all organic Sulphur compounds smell unpleasant at all concentrations: the sulfur-containing monoterpenoid grapefruit mercaptan in small concentrations is the characteristic scent of grapefruit, but has a generic thiol odor at larger concentrations.

Sulphur mustard, a potent vesicant, was used in World War I as a disabling agent.
Sulfur–Sulphur bonds are a structural component used to stiffen rubber, similar to the disulfide bridges that rigidify proteins (see biological below).

In the most common type of industrial "curing" or hardening and strengthening of natural rubber, elemental Sulphur is heated with the rubber to the point that chemical reactions form disulfide bridges between isoprene units of the polymer.

This process, patented in 1843, made rubber a major industrial product, especially in automobile tires.
Because of the heat and sulfur, the process was named vulcanization, after the Roman god of the forge and volcanism.

WHY IS SULPHUR SUCH AN IMPORTANT NUTRIENT?
Many agronomists now consider sulphur to be the second most important nutrient after nitrogen.
Certainly sulphur is an essential nutrient, closely linked with nitrogen in biological processes with both elements forming an inseparable team.

Previously crop requirements were generally met from atmospheric deposition so sulphur was confined to a secondary role, however today it is back in its rightful place as an essential component of optimum nitrogen management.

WHAT ARE SOME PRODUCTS THAT CONTAIN SULPHUR?
Products containing Sulphur can be dusts, wettable powders, liquids, or fumigant gas cartridges.
They are used in field crops, root crops, tree fruits, nuts, berries, vegetables, ornamentals, and turf.

They are also used in outdoor residential areas and on food and non-food crops.
Non-food use sites include pets, livestock, and livestock quarters.

There are over 200 active products containing Sulphur on the market in the United States.
Some have been approved for use in organic gardening.
Non-pesticide products containing Sulphur are used as soil amendments or fertilizers.

HOW DOES SULPHUR WORK?
Sulphur kills fungi on contact.
The way Sulphur works is not completely understood yet.
Some researchers believe Sulphur may react with plants or fungi to produce a toxic agent.
However, the main theory is that Sulphur enters fungi cells and affects cell respiration.

EFFECT OF SULPHUR ON CROP GROWTH:
Sulphur is essential in the structural and enzymatic components in plants.
Sulphur is a key component of some essential amino acids and is needed for protein synthesis.
Chlorophyll synthesis also requires S.

Sulphur is not readily translocated within plants, so all plants need a continuous supply of sulphur from emergence to crop maturity.
In S-deficient plants, older leaves may appear healthier, while newer leaves and tissue may have stunted growth and a lighter green or even yellow appearance.

A sulphur deficiency at any growth stage can result in reduced crop growth and yield.
Adequate S results in rapid crop growth and earlier maturity.

BIOLOGICAL ROLE OF SULPHUR:
Sulphur is an essential component of all living cells.
Sulphur is the eighth most abundant element in the human body by weight, about equal in abundance to potassium, and slightly greater than sodium and chlorine.

A 70 kg (150 lb) human body contains about 140 grams (4.9 oz) of Sulphur.
The main dietary source of Sulphur for humans is sulfur-containing amino-acids, which can be found in plant and animal proteins.

Transferring Sulphur between inorganic and biomolecules
In the 1880s, while studying Beggiatoa (a bacterium living in a Sulphur rich environment), Sergei Winogradsky found that it oxidized hydrogen sulfide (H2S) as an energy source, forming intracellular Sulphur droplets.

Winogradsky referred to this form of metabolism as inorgoxidation (oxidation of inorganic compounds).
Another contributor, who continued to study it was Selman Waksman.

Primitive bacteria that live around deep ocean volcanic vents oxidize hydrogen sulfide for their nutrition, as discovered by Robert Ballard.
Sulphur oxidizers can use as energy sources reduced Sulphur compounds, including hydrogen sulfide, elemental sulfur, sulfite, thiosulfate, and various polythionates (e.g., tetrathionate).

They depend on enzymes such as Sulphur oxygenase and sulfite oxidase to oxidize Sulphur to sulfate.
Some lithotrophs can even use the energy contained in Sulphur compounds to produce sugars, a process known as chemosynthesis.

Some bacteria and archaea use hydrogen sulfide in place of water as the electron donor in chemosynthesis, a process similar to photosynthesis that produces sugars and uses oxygen as the electron acceptor.
Sulfur-based chemosynthesis may be simplifiedly compared with photosynthesis:

H2S + CO2 → sugars + S
H2O + CO2 → sugars + O2

There are bacteria combining these two ways of nutrition: green Sulphur bacteria and purple Sulphur bacteria.
Also sulfur-oxidizing bacteria can go into symbiosis with larger organisms, enabling the later to use hydrogen sulfide as food to be oxidized.
Example: the giant tube worm.

There are sulfate-reducing bacteria, that, by contrast, "breathe sulfate" instead of oxygen.
They use organic compounds or molecular hydrogen as the energy source.

They use Sulphur as the electron acceptor, and reduce various oxidized Sulphur compounds back into sulfide, often into hydrogen sulfide.
They can grow on other partially oxidized Sulphur compounds (e.g. thiosulfates, thionates, polysulfides, sulfites).

There are studies pointing that many deposits of native Sulphur in places that were the bottom of the ancient oceans have biological origin.
These studies indicate that this native Sulphur have been obtained through biological activity, but what is responsible for that (sulfur-oxidizing bacteria or sulfate-reducing bacteria) is still unknown for sure.

Sulphur is absorbed by plants roots from soil as sulfate and transported as a phosphate ester.
Sulfate is reduced to sulfide via sulfite before it is incorporated into cysteine and other organoSulphur compounds.

SO2−4 → SO2−3 → H2S → cysteine (thiol) → methionine (thioether)
While the plants' role in transferring Sulphur to animals by food chains is more or less understood, the role of Sulphur bacteria is just getting investigated.

*Protein and organic metabolites:
In all forms of life, most of the Sulphur is contained in two proteinogenic amino acids (cysteine and methionine), thus the element is present in all proteins that contain these amino acids, as well as in respective peptides.

Some of the Sulphur is comprised in certain metabolites—many of which are cofactors—and sulfated polysaccharides of connective tissue (chondroitin sulfates, heparin).
Proteins, to execute their biological function, need to have specific space geometry.

Formation of this geometry is performed in a process called protein folding, and is provided by intra- and inter-molecular bonds.
The process has several stages.

While at premier stages a polypeptide chain folds due to hydrogen bonds, at later stages folding is provided (apart from hydrogen bonds) by covalent bonds between two Sulphur atoms of two cysteine residues (so called disulfide bridges) at different places of a chain (tertiary protein structure) as well as between two cysteine residues in two separated protein subunits (quaternary protein structure).

Both structures easily may be seen in insulin.
As the bond energy of a covalent disulfide bridge is higher than the energy of a coordinate bond or hydrophobic interaction, higher disulfide bridges content leads to higher energy needed for protein denaturation.

In general disulfide bonds are necessary in proteins functioning outside cellular space, and they do not change proteins' conformation (geometry), but serve as its stabilizers.
Within cytoplasm cysteine residues of proteins are saved in reduced state (i.e. in -SH form) by thioredoxins.

This property manifests in following examples. Lysozyme is stable enough to be applied as a drug.
Feathers and hair have relative strength, and consisting in them keratin is considered indigestible by most organisms.
However, there are fungi and bacteria containing keratinase, and are able to destruct keratin.

Many important cellular enzymes use prosthetic groups ending with -SH moieties to handle reactions involving acyl-containing biochemicals: two common examples from basic metabolism are coenzyme A and alpha-lipoic acid.

Cysteine-related metabolites homocysteine and taurine are other sulfur-containing amino acids that are similar in structure, but not coded by DNA, and are not part of the primary structure of proteins, take part in various locations of mammalian physiology.

Two of the 13 classical vitamins, biotin and thiamine, contain sulfur, and serve as cofactors to several enzymes.
In intracellular chemistry, Sulphur operates as a carrier of reducing hydrogen and its electrons for cellular repair of oxidation.
Reduced glutathione, a sulfur-containing tripeptide, is a reducing agent through its sulfhydryl (–SH) moiety derived from cysteine.

Methanogenesis, the route to most of the world's methane, is a multistep biochemical transformation of carbon dioxide.
This conversion requires several organoSulphur cofactors.
These include coenzyme M, CH3SCH2CH2SO−3, the immediate precursor to methane.

*Metalloproteins and inorganic cofactors
Metalloproteins—in which the active site is a transition metal ion (or metal-sulfide cluster) often coordinated by Sulphur atoms of cysteine residues—are essential components of enzymes involved in electron transfer processes.

Examples include plastocyanin (Cu2+) and nitrous oxide reductase (Cu–S).
The function of these enzymes is dependent on the fact that the transition metal ion can undergo redox reactions.

Other examples include many zinc proteins,[128] as well as iron–Sulphur clusters.
Most pervasive are the ferrodoxins, which serve as electron shuttles in cells.

In bacteria, the important nitrogenase enzymes contain an Fe–Mo–S cluster and is a catalyst that performs the important function of nitrogen fixation, converting atmospheric nitrogen to ammonia that can be used by microorganisms and plants to make proteins, DNA, RNA, alkaloids, and the other organic nitrogen compounds necessary for life.

HISTORY OF SULPHUR:
In a 2,800-year-old document, Homer describes the typical use of sulphur for pest control.
The product of Sulphur's combustion has been for many years the disinfectant used in closed spaces (ship holds, warehouses, barrels to age wine....).

*First fungicide in history
However, Sulphur's specific use for controlling oidium (Uncinula necator) is not described until the early 19th century, when an English gardener (Forsyth,1802) recommended its use for the control of oidium in fruit orchards.
This composition with sulphur to remedy the diseases of these plants is found in the Treaty on the cultivation of fruit trees.

In the middle of the 19th century, this disease spread to the rest of Europe, where it caused a sharp drop in wine production and quality.
Its development and spread require humid and warm weather, between 20º and 27º and can only be controlled by the preventive application of SULPHUR, a remedy that was advocated by (Berkeley, 1846) in England, as well as (Duchatel, 1848) in France.

Since then, Sulphur has been the universally used product for the control of oidium in general, being used massively even today and being one of the most effective fungicides.

NAME OF SULPHUR:
A name in Middle English, introduced at least as early as 1390. Also known as brimstone.
Theophrastus (~300 BCE) wrote μαλώδης ("malódis", an otherwise unknown word) for what may be sulphur impregnated pumice, but Caley and Richards (1956) in their analysis and translation of Περι Λιθον ("Peri Lithon", "About Stones") suggest that the actual word should have been μηλώδης ("milódis", meaning quince-yellow).
Other interpretations have been given.

IMPORTANCE IN AGRICULTURE, SULPHUR:
*ANTI OIDIUM
Sulphur acts when it comes in direct contact with spores and other fungal tissues, preventing and inhibiting their germination and growth.

*ACARICIDE
Sulphur promotes the control of the alterations produced by mites such as red spider and erineum mite.

*NUTRITIONAL
Sulphur acts as a nutrient for plants, improving the quality of the substrate and stimulating vegetative growth.

*SOIL CONDITIONER
Sulphur works by improving the physical, chemical and biological properties of the soil or substrate so that plants can develop under better conditions.

*BIOSTIMULANT
Biostimulants increase the efficiency of the plant metabolism, improving both yield and quality of the harvest.

HISTORY OF SULPHUR:
*Antiquity
Being abundantly available in native form, Sulphur was known in ancient times and is referred to in the Torah (Genesis).
English translations of the Christian Bible commonly referred to burning Sulphur as "brimstone", giving rise to the term "fire-and-brimstone" sermons, in which listeners are reminded of the fate of eternal damnation that await the unbelieving and unrepentant.

Sulphur is from this part of the Bible that Hell is implied to "smell of sulfur" (likely due to its association with volcanic activity).
According to the Ebers Papyrus, a Sulphur ointment was used in ancient Egypt to treat granular eyelids.

Sulphur was used for fumigation in preclassical Greece; this is mentioned in the Odyssey.
Pliny the Elder discusses Sulphur in book 35 of his Natural History, saying that its best-known source is the island of Melos.
He mentions its use for fumigation, medicine, and bleaching cloth.

A natural form of Sulphur known as shiliuhuang (石硫黄) was known in China since the 6th century BC and found in Hanzhong.
By the 3rd century, the Chinese had discovered that Sulphur could be extracted from pyrite.

Chinese Daoists were interested in sulfur's flammability and its reactivity with certain metals, yet its earliest practical uses were found in traditional Chinese medicine.
The Wujing Zongyao of 1044 AD described various formulas for Chinese black powder, which is a mixture of potassium nitrate (KNO
3), charcoal, and sulfur

Indian alchemists, practitioners of the "science of chemicals" (Sanskrit: रसशास्त्र, romanized: rasaśāstra), wrote extensively about the use of Sulphur in alchemical operations with mercury, from the eighth century AD onwards.
In the rasaśāstra tradition, Sulphur is called "the smelly" (गन्धक, gandhaka).

Early European alchemists gave Sulphur a unique alchemical symbol, a triangle atop a cross (