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Information about Astringent

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A crystal of alum, an astringent
An astringent substance is a chemical substance that tends to shrink or constrict body tissues, usually locally after topical medicinal application. The word "astringent" derives from Latin astringere, meaning "to bind fast". Two common examples are calamine lotion and witch hazel.

Astringency is also the dry, puckering mouthfeel caused by tannins found in many fruits such as blackthorn, bird cherry and persimmon fruits. The tannins denature the salivary proteins, causing a rough "sandpapery" sensation in the mouth. Astringency tastes unpleasant to many mammals (including humans), which tend to avoid eating astringent fruit; conversely, birds do not taste astringency and readily eat these fruit. It is thought that fruit astringency gives a selective advantage to some plant varieties because birds are better than mammals at long-distance seed dispersal, often flying a great distance before passing the seeds in their droppings.

Astringent substances are also found in some wines and teas. A small amount of astringency is expected in some wines, especially young red wines made from grapes such as cabernet sauvignon.

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A bottle of tannic acid, an astringent


Astringent medicines cause shrinkage of mucous membranes or exposed tissues and are often used internally to check discharge of blood serum or mucous secretions. This can happen with a sore throat, hemorrhages, diarrhea, or with peptic ulcers. Externally applied astringents, which cause mild coagulation of skin proteins, dry, harden, and protect the skin. Acne sufferers are often advised to use astringents if they have oily skin. [1] Astringents also help heal stretch marks and other scars. Mild astringent solutions are used in the relief of such minor skin irritations as those resulting from superficial cuts, allergies, insect bites, or fungal infections such as athlete's foot.

Some common astringent agents include alum, oatmeal, yarrow, witch hazel, bayberry, very cold water, and rubbing alcohol. Astringent preparations include silver nitrate, zinc oxide, zinc sulfate, Burow's solution, tincture of benzoin, and vegetable substances such as tannic and gallic acids. Balaustines are the red rose-like flowers of the pomegranate, which are very bitter to the taste. In medicine, its dried form has been used as an astringent.[1] Some metal salts and acids have also been used as astringents.



References

Biological tissue is a collection of interconnected cells that perform a similar function within an organism.

The study of tissue is known as histology, or, in connection with disease, histopathology.
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In medicine, a topical medication is applied to body surfaces such as the skin or mucous membranes such as the vagina, penis, anus, throat, eye or the ear. Some hydrophobic chemicals such as steroid hormones can be absorbed into the body after being applied to the skin in the form
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Latin}}} 
Official status
Official language of: Vatican City
Used for official purposes, but not spoken in everyday speech
Regulated by: Opus Fundatum Latinitas
Roman Catholic Church
Language codes
ISO 639-1: la
ISO 639-2: lat
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Calamine is a mixture of zinc oxide (ZnO) with about 0.5% iron(III) oxide (Fe2O3). It is the main ingredient in calamine lotion and is used as an antipruritic to treat sunburn, eczema, rashes, poison ivy, chickenpox, insect bites and stings.
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Witch hazel is an astringent produced from the leaves and bark of the North American Witch Hazel shrub (Hamamelis virginiana) which ranges from Nova Scotia west to Ontario, and south to Texas, and Florida.
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Mouthfeel is a product’s physical and chemical interaction in the mouth. It is a concept used in many areas related to the testing and evaluating of foodstuffs, such as wine-tasting and rheology.
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Tannins are astringent, bitter-tasting plant polyphenols that bind and precipitate proteins. The term tannin refers to the use of tannins in tanning animal hides into leather; however, the term is widely applied to any large polyphenolic compound containing sufficient hydroxyls
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fruit has different meanings depending on context. In botany, a fruit is the ripened ovary—together with seeds—of a flowering plant. In many species, the fruit incorporates the ripened ovary and surrounding tissues.
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P. spinosa

Binomial name
Prunus spinosa
L.

Prunus spinosa (Blackthorn) is a species of Prunus native to Europe, western Asia, and locally in northwest Africa.
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P. padus

Binomial name
Prunus padus
L.

For the subgenus Padus, see .


The Bird Cherry (Prunus padus; syn. Cerasus padus (L.
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Persimmon is any of a number of species of trees of the genus Diospyros, and the edible fruit borne by them. The word persimmon is derived from putchamin, pasiminan, or pessamin
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Mammalia
Linnaeus, 1758

Subclasses & Infraclasses
  • Subclass †Allotheria*
  • Subclass Prototheria
  • Subclass Theria

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Aves
Linnaeus, 1758

Orders

About two dozen - see section below

Birds (class Aves) are bipedal, warm-blooded, egg-laying vertebrate animals.
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Natural selection is the process by which favorable traits that are heritable become more common in successive generations of a population of reproducing organisms, and unfavorable traits that are heritable become less
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For other meanings of seed, see seed (disambiguation).


SEED

General
KISA
1998

Cipher detail
Key size(s):| 128 bits

Block size(s):| 128 bits
Nested Feistel network
16

SEED
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Feces, faeces, or fæces (see spelling differences) is a waste product from an animal's digestive tract expelled through the anus (or cloaca) during defecation. The word faeces is the plural of the Latin word fæx meaning "dregs".
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Wine is an alcoholic beverage made from the fermentation of grape juice.[1] The natural chemical balance of grapes is such that they can ferment without the addition of sugars, acids, enzymes or other nutrients.
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Without proper rendering support, you may see question marks, boxes, or other symbols instead of Chinese characters.
Tea is a beverage made by steeping processed leaves, buds, or twigs of the tea bush, Camellia sinensis
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Cabernet Sauvignon is a variety of red grape mainly used for wine production, and is, along with Chardonnay, one of the most widely-planted of the world's grape varieties.
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The mucous membranes (or mucosae; singular: mucosa) are linings of mostly endodermal origin, covered in epithelium, and are involved in absorption and secretion. They line various body cavities that are exposed to the external environment and internal organs.
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Blood plasma is the liquid component of blood, in which the blood cells are suspended. It makes up about 55% of total blood volume. Blood plasma is prepared simply by spinning a tube of fresh blood in a centrifuge until the blood cells fall to the bottom of the tube.
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Bleeding, technically known as hemorrhage (American English) or haemorrhage (British English) is the loss of blood from the circulatory system.[1] Bleeding can occur internally, where blood leaks from blood vessels inside the body or externally, either
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MeSH D003967 Diarrhea (in American English) or diarrhoea (in British English) is a condition in which the sufferer has frequent watery, loose bowel movements (from the Greek word διάρροια; literally meaning "through-flowing").
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MeSH D010437

A peptic ulcer, also known as PUD or peptic ulcer disease[1] is an ulcer of an area of the gastrointestinal tract that is usually acidic and thus extremely painful.
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Proteins are large organic compounds made of amino acids arranged in a linear chain and joined together by peptide bonds between the carboxyl and amino groups of adjacent amino acid residues.
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Skin layers: epidermis, dermis, and subcutis, showing a hair follicle, sweat gland & sebaceous gland.]] In zootomy and dermatology, skin is the largest organ of the integumentary system made up of multiple layers of epithelial tissues that guard underlying muscles and organs.
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Acne
Classification & external resources

Acne of a 14 year old boy during puberty
ICD-10 L 70.0
ICD-9 706.1

DiseasesDB 10765
MedlinePlus 000873
eMedicine derm/2   Acne Vulgaris
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Insecta
Linnaeus, 1758

Orders
Subclass Apterygota
* Archaeognatha (bristletails)
* Thysanura (silverfish)
Subclass Pterygota
* Infraclass Paleoptera (Probably paraphyletic)

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Athlete's foot or tinea pedis
Classification & external resources

Pale, flaky & split skin of athlete's foot in a toe web space
ICD-10 B 35.3
ICD-9 110.
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For alum meaning "graduate," see Alumnus.


Alum, (IPA: /ˈæləm/) (aluminium potassium sulfate,) in chemistry, is a term given to the crystallized double sulfates of the typical
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