|
Prunasin
(''R'')-prunasin is a cyanogenic glycoside related to amygdalin. Chemically, it is the glucoside of (''R'')-mandelonitrile. Natural occurrences Prunasin is found in species in the genus ''Prunus'' such as ''Prunus japonica'' or '' P. maximowiczii'' and in bitter almonds. It is also found in leaves and stems of '' Olinia ventosa'', '' O. radiata'', '' O. emarginata'' and '' O. rochetiana'' and in ''Acacia greggii''. It is a biosynthetic precursor of and intermediate in the biosynthesis of amygdalin, the chemical compound responsible for the taste of bitter almond. It is also found in dandelion coffee, a coffee substitute. Sambunigrin Sambunigrin, a diastereomer of prunasin derived from (''S'')-mandelonitrile instead of it the (''R'')-isomer, has been isolated from leaves of the elder tree (''Sambucus nigra''). Sambunigrin is present in the leaves and stems of elder at a 1:3 ratio of sambunigrin to prunasin, and 2:5 in the immature seed. It is not found in the root. Biosynthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prunasin Biosynthetic Mechanism
(''R'')-prunasin is a cyanogenic glycoside related to amygdalin. Chemically, it is the glucoside of (''R'')-mandelonitrile. Natural occurrences Prunasin is found in species in the genus ''Prunus'' such as ''Prunus japonica'' or '' P. maximowiczii'' and in bitter almonds. It is also found in leaves and stems of '' Olinia ventosa'', '' O. radiata'', '' O. emarginata'' and '' O. rochetiana'' and in ''Acacia greggii''. It is a biosynthetic precursor of and intermediate in the biosynthesis of amygdalin, the chemical compound responsible for the taste of bitter almond. It is also found in dandelion coffee, a coffee substitute. Sambunigrin Sambunigrin, a diastereomer of prunasin derived from (''S'')-mandelonitrile instead of it the (''R'')-isomer, has been isolated from leaves of the elder tree (''Sambucus nigra''). Sambunigrin is present in the leaves and stems of elder at a 1:3 ratio of sambunigrin to prunasin, and 2:5 in the immature seed. It is not found in the root. Biosynthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olinia Ventosa
''Olinia ventosa'', commonly known as the hard-pear. is a large, evergreen forest tree indigenous to South Africa. Appearance The hard-pear is a large tree that usually grows to 15–20 meters in height. When exposed to harsh conditions, it forms a smaller tree or shrub. The bark is originally smooth and grey, but it becomes rough, flaky, fissured and reddish as the tree matures. The leathery, dark green, glossy leaves appear in opposite pairs, while the pinkish-white, fragrant, bisexual flowers appear in bunches at branch ends in the spring. The tree very occasionally bears pinkish-red berries. The hard-pear can sometimes be identified by the strong smell of almonds given off by the crushing of its leaves. Distribution ''Olinia ventosa'' is a native of the southern and eastern coastal regions of South Africa, from the Cape Peninsula to southern KwaZulu-Natal. Its natural habitat is afro-montane forests, especially the forest margins, as well as coastal scrub and rocky hil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amygdalin
Amygdalin (from Ancient Greek: ' "almond") is a naturally occurring chemical compound found in many plants, most notably in the seeds (kernels) of apricots, bitter almonds, apples, peaches, cherries, and plums. Amygdalin is classified as a cyanogenic glycoside because each amygdalin molecule includes a nitrile group, which can be released as the toxic cyanide anion by the action of a beta-glucosidase. Eating amygdalin will cause it to release cyanide in the human body, and may lead to cyanide poisoning. Since the early 1950s, both amygdalin and a chemical derivative named ''laetrile'' have been promoted as alternative cancer treatments, often under the misnomer vitamin B17 (neither amygdalin nor laetrile is a vitamin). Scientific study has found them to not only be clinically ineffective in treating cancer, but also potentially toxic or lethal when taken by mouth due to cyanide poisoning. The promotion of laetrile to treat cancer has been described in the medical literature a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanogenic Glycoside
In chemistry, a glycoside is a molecule in which a sugar is bound to another functional group via a glycosidic bond. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. These can be activated by enzyme hydrolysis, which causes the sugar part to be broken off, making the chemical available for use. Many such plant glycosides are used as medications. Several species of ''Heliconius'' butterfly are capable of incorporating these plant compounds as a form of chemical defense against predators. In animals and humans, poisons are often bound to sugar molecules as part of their elimination from the body. In formal terms, a glycoside is any molecule in which a sugar group is bonded through its anomeric carbon to another group via a glycosidic bond. Glycosides can be linked by an O- (an ''O-glycoside''), N- (a ''glycosylamine''), S-(a ''thioglycoside''), or C- (a '' C-glycoside'') glycosidic bond. According to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Almond
The almond (''Prunus amygdalus'', syn. ''Prunus dulcis'') is a species of tree native to Iran and surrounding countries, including the Levant. The almond is also the name of the edible and widely cultivated seed of this tree. Within the genus ''Prunus'', it is classified with the peach in the subgenus ''Amygdalus'', distinguished from the other subgenera by corrugations on the shell (endocarp) surrounding the seed. The fruit of the almond is a drupe, consisting of an outer hull and a hard shell with the seed, which is not a true nut. ''Shelling'' almonds refers to removing the shell to reveal the seed. Almonds are sold shelled or unshelled. Blanched almonds are shelled almonds that have been treated with hot water to soften the seedcoat, which is then removed to reveal the white embryo. Once almonds are cleaned and processed, they can be stored over time. Almonds are used in many food cuisines, often featuring prominently in desserts, such as marzipan. The almond tree p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bitter Almond
The almond (''Prunus amygdalus'', syn. ''Prunus dulcis'') is a species of tree native to Iran and surrounding countries, including the Levant. The almond is also the name of the edible and widely cultivated seed of this tree. Within the genus ''Prunus'', it is classified with the peach in the subgenus ''Amygdalus'', distinguished from the other subgenera by corrugations on the shell (endocarp) surrounding the seed. The fruit of the almond is a drupe, consisting of an outer hull and a hard shell with the seed, which is not a true nut. ''Shelling'' almonds refers to removing the shell to reveal the seed. Almonds are sold shelled or unshelled. Blanched almonds are shelled almonds that have been treated with hot water to soften the seedcoat, which is then removed to reveal the white embryo. Once almonds are cleaned and processed, they can be stored over time. Almonds are used in many food cuisines, often featuring prominently in desserts, such as marzipan. The almond tree pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acacia Greggii
''Senegalia greggii'', formerly known as ''Acacia greggii'', is a species of tree in the genus ''Senegalia'' native to the southwestern United States and northern Mexico, from the extreme south of Utah south through southern Nevada, southeast California, Arizona, New Mexico and western Texas to Baja California, Sinaloa and Nuevo León in Mexico. The population in Utah at 37°10' N is the northernmost naturally occurring ''Senegalia'' species anywhere in the world. Common names include acacia bush, catclaw acacia, catclaw mesquite, Gregg's catclaw, paradise flower, wait-a-minute bush, and wait-a-bit tree; these names mostly come from the fact that the tree has numerous hooked prickles with the shape and size of a cat's claw which tend to hook onto passers-by; the hooked person must stop ("wait a minute") to remove the prickles carefully to avoid injury or shredded clothing. (The common name "cat's claw" is also used to refer to several other plant species, including ''Uncaria to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olinia Emarginata
''Olinia emarginata'', the mountain hard pear or berghardepeer in Afrikaans language, is a tree species in the genus ''Olinia'' native to South Africa. Prunasin, a cyanogenic glucoside, can be found in the leaves of ''O. emarginata''.Occurrence of the cyanogenic glucoside prunasin and II corresponding mandelic acid amide glucoside in ''Olinia'' species (Oliniaceae). Adolf Nahrstedt and Jürgen Rockenbach, September 1993, Phytochemistry, Volume 34, Issue 2, Pages 433–436, See also * List of Southern African indigenous trees and woody lianes * Forests of KwaZulu-Natal Areas of forest which grow in KwaZulu-Natal, South Africa mostly on south facing slopes in higher rainfall areas, and along the humid coastal areas. Different types of forest can be identified by their species composition which depends mostly o ... References External links http://plants.jstor.org Penaeaceae Flora of South Africa {{Myrtales-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bitter Almond
The almond (''Prunus amygdalus'', syn. ''Prunus dulcis'') is a species of tree native to Iran and surrounding countries, including the Levant. The almond is also the name of the edible and widely cultivated seed of this tree. Within the genus ''Prunus'', it is classified with the peach in the subgenus ''Amygdalus'', distinguished from the other subgenera by corrugations on the shell (endocarp) surrounding the seed. The fruit of the almond is a drupe, consisting of an outer hull and a hard shell with the seed, which is not a true nut. ''Shelling'' almonds refers to removing the shell to reveal the seed. Almonds are sold shelled or unshelled. Blanched almonds are shelled almonds that have been treated with hot water to soften the seedcoat, which is then removed to reveal the white embryo. Once almonds are cleaned and processed, they can be stored over time. Almonds are used in many food cuisines, often featuring prominently in desserts, such as marzipan. The almond tree pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prunus Maximowiczii
''Prunus maximowiczii'', known as Korean cherry, Korean mountain cherry, or Miyama cherry, is a small (about 7.5 m), fruiting cherry tree that can be found growing wild in northeastern Asia and Eurasia. Taxonomy The species was first described in 1857 by Franz Josef Ruprecht. It was treated in the genus ''Cerasus'' (now generally accepted as a subgenus of ''Prunus'') by Vladimir Leontyevich Komarov in 1927, but the original ''P. maximowiczii'' remains the widely accepted binomial. Description ''P. maximowiczii'' has white, insect-pollinated, hermaphroditic flowers, blooming in May in the Northern Hemisphere, November in the Southern Hemisphere. The edible fruits (cherries) are about 5 mm in diameter, containing one large seed each. They ripen in August in the Northern Hemisphere, February in the Southern Hemisphere. Range and habitat Korea, China (Heilong Jiang, Jilin, Liaoning, and Zhejiang), Russia (Khabarovsk, Primorye, and Sakhalin), and Japan (Hokkaido, Honshu, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mandelonitrile
In organic chemistry, mandelonitrile is the nitrile of mandelic acid, or the cyanohydrin derivative of benzaldehyde. Small amounts of mandelonitrile occur in the pits of some fruits. Occurrence Mandelonitrile is the aglycone part of the cyanogenic glycosides prunasin and amygdalin. The naturally occurring (''R'')-(+) enantiomer finds use as an intermediate in the preparation of optically active α-hydroxy carboxylic acids, α-hydroxy aldehydes, α-hydroxy ketones, and 2-amino alcohols.Kruse, C.G. In Collins, A.N. Sheldrake, G.N. Crosby, J., Eds. ''Chirality in Industry Chichester'', UK , (1992), 279 Mandelonitrile can break down into cyanide and benzaldehyde, a reaction that can be catalyzed by the enzyme mandelonitrile lyase. Preparation Racemic mandelonitrile may be prepared similar to many other cyanohydrins. In a one pot reaction, benzaldehyde is reacted with sodium bisulfite to give the corresponding adduct, which further reacts with aqueous sodium cyanide Sodium c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cotyledon
A cotyledon (; ; ; , gen. (), ) is a significant part of the embryo within the seed of a plant, and is defined as "the embryonic leaf in seed-bearing plants, one or more of which are the first to appear from a germinating seed." The number of cotyledons present is one characteristic used by botanists to classify the flowering plants (angiosperms). Species with one cotyledon are called monocotyledonous ("monocots"). Plants with two embryonic leaves are termed dicotyledonous ("dicots"). In the case of dicot seedlings whose cotyledons are photosynthetic, the cotyledons are functionally similar to leaves. However, true leaves and cotyledons are developmentally distinct. Cotyledons are formed during embryogenesis, along with the root and shoot meristems, and are therefore present in the seed prior to germination. True leaves, however, are formed post-embryonically (i.e. after germination) from the shoot apical meristem, which is responsible for generating subsequent aerial por ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
