Thursday, January 3, 2013

Malaysian Herbs- OAK-QUERCUS ALBA (48)

google.com, pub-7876390333399498, DIRECT, f08c47fec0942fa0
http://www.sidhhaherbs.blogspot.com            OAK TREE

Quercus alba

Oak wood has a density of about 0.75 g/cm3, great strength and hardness, and is very resistant to insect and fungal attack because of its high tannin content


White oak has served as the official state tree of Illinois after selection by a vote of school children. There are two "official" white oaks serving as state trees, one located on the grounds of the governor's mansion, and the other in a schoolyard in the town of Rochelle. The white oak is also the state tree of Connecticut and Maryland. The Wye Oak, probably the oldest living white oak until it fell because of a thunderstorm on June 6, 2002, was the honorary state tree of Maryland


Quercus alba, the white oak, is one of the pre-eminent hardwoods of eastern North America. It is a long-lived oak of the familyFagaceae, native to eastern North America and found from southern Quebec west to eastern Minnesota and south to northern Florida and eastern Texas. Specimens have been documented to be over 450 years old.
Although called a white oak, it is very unusual to find an individual specimen with white bark; the usual color is a light gray. In the forest it can reach a magnificent height and in the open it develops into a massive broad-topped tree with large branches striking out at wide angles.


White Oak (Quercus alba) leavesNormally not a very tall tree, typically reaching 65–85 feet (19.5-25.5 m) at maturity, it nonetheless becomes quite massive and its lower branches are apt to extend far out laterally, parallel to the ground. The tallest known white oak is 144 feet (43 m) tall. It is not unusual for a white oak tree to be as wide as it is tall, but specimens growing at high altitudes may only become small shrubs. White oaks have been known to live up to six hundred years. The bark is a light ash-gray and peels somewhat from the top, bottom and/or sides.

Quercus alba


Quercus alba, the white oak, is one of the pre-eminent hardwoods of eastern North America. It is a long-lived oak of the familyFagaceae, native to eastern North America and found from southern Quebec west to eastern Minnesota and south to northern Florida and eastern Texas. Specimens have been documented to be over 450 years old.
In spring the young leaves are of a delicate, silvery pink and covered with a soft, blanket-like down. The petioles are short, and the leaves which cluster close to the ends of the shoots are pale green and downy with the result that the entire tree has a misty, frosty look. This condition continues for several days, passing through the opalescent changes of soft pink, silvery white and finally yellow green.
The leaves grow to be 5-8.5 inches long and 2.75-4.5 inches wide and have a deep glossy green upper surface. They usually turn red or brown in autumn, but depending on climate, site, and individual tree genetics, some trees are nearly always red, or even purple in autumn. Some brown, dead leaves may remain on the tree throughout winter until very early spring. The lobes can be shallow, extending less than halfway to the midrib, or deep and somewhat branching. The acorns are usually sessile, and grow to 0.5-1 inch in length, falling in early October.
Quercus alba is sometimes confused with the swamp white oak, a closely related species, and the bur oak. The 

Uses

White oak has tyloses that give the wood a closed cellular structure, making it water- and rot-resistant. Because of this characteristic, white oak is used for barrels for wine and whiskey production since it resists leaking. It has also been used in construction, shipbuilding, cooperage, agricultural implements, and in the interior finishing of houses.[3]
It was a signature wood used in mission style oak furniture by Gustav Stickley in the Craftsman style of the Arts and Crafts movement.[citation needed]
White oak is used extensively in Japanese martial arts for some weapons, such as the bokken and jo. It is valued for its density, strength, resiliency and relatively low chance of splintering if broken by impact, relative to the substantially cheaper red oak.
The acorns are much less bitter than the acorns of red oaks. They are small relative to most oaks, but are a valuable wildlife food, notably for turkeys, wood ducks, pheasants, grackles, jays, nuthatches, thrushes, woodpeckers, rabbits, squirrels and deer. They were also used for food by Native Americans. The white oak is the only known food plant of the Bucculatrix luteella and Bucculatrix ochrisuffusa caterpillars.
The young shoots of many eastern oak species are readily eaten by deer.Dried oak leaves are also occasionally eaten by white-tailed deer in the fall or winter. Rabbits often browse twigs and can girdle stems.
The USS Constitution is made of white oak, and reconstructive wood replacement comes from a special grove of Quercus albaknown as the "Constitution Grove" at Naval Surface Warfare Center Crane Division.
Woodworkers should be aware that ferrous metal hardware reacts with oak, causing corrosion and staining the wood. Brass or stainless steel fittings should be used instead.

Symbolism

White oak has served as the official state tree of Illinois after selection by a vote of school children. There are two "official" white oaks serving as state trees, one located on the grounds of the governor's mansion, and the other in a schoolyard in the town ofRochelle. The white oak is also the state tree of Connecticut and Maryland. The Wye Oak, probably the oldest living white oak until it fell because of a thunderstorm on June 6, 2002, was the honorary state tree of Maryland.
Being the subject of a legend as old as the colony itself, the Charter Oak of Hartford, Connecticut is one of the most famous white oaks in America. An image of the tree now adorns the reverse side of the Connecticut state quarter.

Chemistry

Grandinin/roburin Ecastalagin/vescalagingallic acid, monogalloyl glucose (glucogallin) andvaloneic acid dilactone, monogalloyl glucose, digalloyl glucosetrigalloyl glucoseellagic acid rhamnosequercitrin and ellagic acid are phenolic compounds found in Q. alba.

Garden Uses

Large shade tree, street tree or lawn tree. Needs a large space in which to grow. 
physciapackiam

http://www.sidhhaherbs.blogspot.com     (48)

Monday, December 31, 2012

Malaysian Herbs-ACACIA GUM-(47)அரேபிக் கம்

google.com, pub-7876390333399498, DIRECT, f08c47fec0942fa0
http://www.sidhhaherbs.blogspot.com

அன்பர்களே சஹாரா பாலைவனத்தின் செடிகளை அறிவீர்களா?
                       Gum Arabic      

 Also known as acacia gumchaar gundchar goond, or meska, is a natural gum made of hardened sap taken from two species of the acacia tree; Acacia senegal and Acacia seyal. The gum is harvested commercially from wild trees throughout the Sahel from Senegal and Sudan to Somalia, although it has been historically cultivated in Arabia and West Asia.
Gum Arabic is a complex mixture of glycoproteins and polysaccharides. It was historically the source of the sugars arabinose and ribose, both of which were first discovered and isolated from it, and are named for it.
Gum Arabic is used primarily in the food industry as a stabilizer. It is edible and has E number E414. Gum arabic is a key ingredient in traditional lithography and is used in printing, paint production, glue, cosmetics and various industrial applications, including viscositycontrol in inks and in textile industries, although less expensive materials compete with it for many of these roles.

While gum Arabic is now produced mostly throughout the African Sahel, it is still harvested and used in the Middle East. For example, Arab populations use natural gum to make a chilled, sweetened, and flavored gelato-like desseGum Arabic mixture of saccharides and glycoproteins gives it the properties of a glue and binder which is edible by humans. Other substances have replaced it in situations where toxicity is not an issue, as the proportions of the various chemicals in gum Arabic vary widely and make it unpredictable. Still, it remains an important ingredient in soft drink syrups, "hard" gummy candies such as gumdropsmarshmallowsM&M's chocolate candies, and edible glitter, a very popular, modern cake-decorating staple. For artists, it is the traditional binder used in watercolor paint, in photography for gum printing, and it is used as a binder in pyrotechnic compositions. It has been investigated for use in intestinal dialysisPharmaceuticals and cosmetics also use the gum as a binder, emulsifying agent and a suspending or viscosity-increasing agent. Gum Arabic has been used in the past as a wine fining agent.
It is an important ingredient in shoe polish and can be used in making homemade incense cones. It is also used as a lickable adhesive, for example on postage stamps andcigarette papers. Lithographic printers employ it to keep the non-image areas of the plate receptive to water. This treatment also helps to stop the oxidation of aluminum printing plates in the interval between the processing of the plate and its use on a printing press.


Powdered gum arabic for artists, one part gum arabic is dissolved in four parts distilled water to make a liquid suitable for adding to pigments.

A selection of gouaches containing gum arabic
Gum Arabic is used as a binder for watercolor painting because it dissolves easily in water. The pigment of any color is suspended within the acacia gum in varying amounts, resulting in watercolor paint. Water acts as a vehicle or a diluent to thin the watercolor paint and helps to transfer the paint to a surface such as paper. When all moisture evaporates, the acacia gum binds the pigment to the paper surface. After the water evaporates, the acacia gum in the paint film increases luminosity and helps prevent the colors from lightening. Gum arabic allows more precise control over washes, because it prevents them from flowing or bleeding beyond the brush stroke. In addition, acacia gum slows evaporation of water, giving slightly longer working time.

Photography
The historical photography process of gum bichromate photography uses gum arabic mixed with ammonium or potassium dichromate and pigment to create a colored photographic emulsion that becomes relatively insoluble in water upon exposure to ultraviolet light. In the final print, the acacia gum permanently binds the pigments onto the paper.

Printmaking

Gum Arabic is also used to protect and etch an image in lithographic processesInk tends to fill into white space on photosensitive aluminum plates if they do not receive a layer of gum. In lithography, the gum etch is used to etch the most subtle gray tones. Phosphoric acid is added in varying concentrations to the acacia gum to etch the darker tones up to dark blacks. Multiple layers of gum are used after the etching process to build up a protective barrier that ensures the ink does not fill into the whitespace of the image being printed.
It is also possible to print from black and white photocopies using a 50% Gum Arabic solution. This is carefully sponged onto the photocopy, and oil-based ink of any colour is rolled over the photocopy. The ink can be removed fairly easily from the white areas by carefully wiping with a damp sponge and the "paper plate" used to print using an etching press.

Pyrotechnics

Gum rabic is also used as a water-soluble binder in fireworks composition.

Physical properties

Effect on surface tension in liquids

Acacia gum reduces the surface tension of liquids, which leads to increased fizzing in carbonated beverages. This can be exploited in what is known as a Diet Coke and Mentos eruption.

Production

Acacia senegal from Paul Hermann Wilhelm Taubert's Leguminosae, in Engelmann (ed.): Natürliche Pflanzenfamilien. Vol. III, 3., 1891

Acacia seyal from Paul Hermann Wilhelm Taubert's Leguminosae, in Engelmann (ed.): Natürliche Pflanzenfamilien. Vol. III, 3., 1891
While acacia gum has been harvested in ArabiaEgypt, and West Asia since antiquity, sub-Saharan acacia gum has a long history as a prized export. The gum exported came from the band of acacia trees that once covered much of the Sahel region: the southern littoral of the Sahara Desert running from the Atlantic to the Red Sea. Today, the main populations of gum-producing Acacia species are harvested in MauritaniaSenegalMaliBurkina FasoNigerNigeriaChadCameroonSudanEritreaSomaliaEthiopiaKenya and TanzaniaAcacia Senegal is tapped for gum by cutting holes in the bark, from which a product called Kordofan or Senegal gum is exuded. Seyal gum, from Acacia seyal, the species more prevalent in East Africa, is collected from naturally occurring extrusions on the bark. Traditionally harvested by seminomadic desert pastoralists in the course of their transhumance cycle, acacia gum remains a main export of several African nations, including MauritaniaNigerChad, and Sudan. The hardened extrusions are collected in the middle of the rainy season (harvesting usually begins in July), and exported at the start of the dry season (November). Total world gum Arabic exports are today (2008) estimated at 60,000 tonnes, having recovered from 1987–1989 and 2003–2005 crises caused by the destruction of trees by the desert locust. Sudan, Chad, and Nigeria, which in 2007 together produced 95% of world exports, have been in discussions to create a producers' cartel.[4]

Political aspects

Senegambia

In 1445, Prince Henry the Navigator set up a trading post on Arguin Island (off the coast of modern Mauritania), which acquired acacia gum and slaves for Portugal. With the merger of the Portuguese and Spanish crowns in 1580, the Spaniards became the dominant influence along the coast. In 1638, however, they were replaced by the Dutch, who were the first to begin exploiting the acacia gum trade. Produced by the acacia trees of Trarza and Brakna, and used in textile pattern printing, this acacia gum was considered superior to that previously obtained in Arabia. By 1678, the French had driven out the Dutch and established a permanent settlement at Saint Louis at the mouth of the Senegal River, where the French Company of the Senegal River (Compagnie Française du Sénégal) had been trading for more than fifty years.[5]

Moorish tribes meet to trade gum arabic at Bakel on the Senegal river, 1890 (illustration from "Côte occidentale d'Afrique du Colonel Frey", pl. en reg. p. 100)
For much of the 19th century, gum Arabic was the major export from French and British trading colonies in modern Senegal and Mauritania. France in particular first came into conflict with inland African states over the supply of the commodity, providing an early spur for the conquest of French West Africa. As the Atlantic slave trade weakened in the early 19th century, The Emirate of Trarza and its neighbors, in what is today southern Mauritania, collected taxes on trade, especially gum arabic, which the French were purchasing in ever-increasing quantities for its use in industrial fabric production. West Africa had become the sole supplier of world acacia gum by the 18th century, and its export at the French colony of Saint-Louis doubled in the decade of 1830 alone. Taxes, and a threat to bypass Saint-Louis by sending gum to the British traders at Portendick, eventually brought the Emirate of Trarza into direct conflict with the French. In the 1820s, the French launched the Franco-Trarzan War of 1825. The new emir, Muhammad al Habib, had signed an agreement with the Waalo Kingdom, directly to the south of the river. In return for an end to raids in Waalo territory, the Emir took the heiress of Waalo as a bride. The prospect that Trarza might inherit control of both banks of Senegal struck at the security of French traders, and the French responded by sending a large expeditionary force that crushed Muhammad's army. The war incited the French to expand to the north of the Senegal River for the first time, heralding French direct involvement in the interior of West Africa. Gum Arabic continued to be exported in large quantities from the Sahel areas of French West Africa (modern Senegal, Mauritania, Mali, Burkina Faso, and Niger) and French Equatorial Africa (modern Chad) until these nations gained their independence in 1959-61.

Sudan

Although from the 1950s to the early 1990s, Sudan accounted for roughly 80% of gum Arabic production, today, that figure is under 50%. Hundreds of thousands of poor Sudanese are dependent on gum Arabic for their livelihoods. It is, however, still the world's largest single producer, and the production of gum Arabichttp:// is heavily controlled by the Sudanese government.
The connection between Sudan and Osama bin Laden brought the otherwise innocuous gum to public consciousness in 2001, as an urban legend arose that bin Laden owned a significant fraction of the gum arabic production in Sudan, and therefore one should boycott products using it.
This story took on somewhat significant proportions, mostly due to an article in The Daily Telegraph a few days after the September 11 attacks, which echoed this claim. Eventually, the State Department issued a release stating that while Osama bin Laden had once had considerable holdings in Sudanese gum Arabichttp:// production, he divested himself of these when he was expelled from Sudan in 1996.
In a press conference held at the Washington Press Club on 30 May 2007, John Ukec Lueth Ukec, Sudan's ambassador to the United States, threatened to stop the exportation of gum arabic from his country if sanctions were imposed. The sanctions proposed by the United States were a political response from the United States to the alleged connection between the government of Sudan and the Janjaweed militia group. Ukec made his speech surrounded by Coca-Cola products, although other sodas use acacia gum as an emulsifier, as well.
Ukec was quoted at the Washington press conference, "I want you to know that the gum Arabic which runs all the soft drinks all over the world, including the United States, mainly 80 percent is imported from my country," which he said after raising a bottle of Coca-Cola. According to the Washington Post, a reporter then asked if Sudan was threatening to "stop the export of gum Arabic and bring down the Western world." To which Ukec replied, "I can stop that gum Arabic and all of us will have lost this," and gestured to the Coke bottle.
THANKS, VIKI

Acacia gum has been used since 2650 BC, at the time of ancient Egypt, when it was used in the manufacture of bandages for mummies1 and for food. Its production area spreads far and wide across the “gum belt”, extending from Senegal to Eritrea, in dry and semi-arid areas of the south of Sahara.  

Acacia gum is a tremendous economic resource for poor populations of the Sahel. In these territories, around three million people can live their lives thanks to the acacia gum crop2. Acacia trees also represents a great asset for farming and local communities, as it can acclimatise perfectly to dry and desert areas.
Besides its economic interest for the poorest local populations, the harvest of acacia gum has a very positive impact on environmental protection. Acacia trees nourish the soil by fixing nitrogen and restoring fertility. They give shelter and shade to farmers and animals while producing Acacia Gum. They are a sustainable resource, and their harvest increases the productivity of other cultivations and prevent desertification.

Acacia trees are also protecting local biodiversity: In addition to supplying forage for cattle, acacias are a genuine home for several bird species. The root system of acacias can go down to the water table while avoiding soil degradation3. Acacias are able to hold available water, even from remote depths. The grass carpet created by the bush prevents water run-off and contributes to the reconstruction of water tables. In periods of drought, when the water runs out, acacias provide a much-needed water supply to wildlife and domestic species.   

Beyond the amazing natural properties specific to acacia gum5, it is interesting to know that the crop is also 100% organic. Acacia gum harvest can’t be mechanized. Acacia gum supplied by Alland & Robert, one the leading global suppliers well recognized by the largest food groups, is organic, GMO-free, and guaranteed without any pesticide6. Alland & Robert is involved in Africa with a policy of social, environmental, and economic responsibility.