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in the leaves of other Solanaceae plants including tomato, potato, eggplant and pepper. It has useful medicinal properties and is known to possess anti-bacterial, anti-inflammation, and anti-ulcer activities (Khidyrova NK et al., Chem Nat Compd 2002, 38, 107). Industrially, solanesol |
is extracted from Solanaceae leaves (about 450 tons in 2008) and used as an intermediate in the synthesis of coenzyme Q10 and vitamin K analogues. Spadicol was discovered in the spadix (inflorescence) of the Araceae Arum maculatum (Hemming FW et |
al., Proc R Soc London 1963, 158, 291). Its presence is likely related to its presence in the ubiquinone as the side-chain. Phytol is a partially saturated diterpene, a monounsaturated derivative of geranylgeraniol which is part of the chlorophyll molecule |
: - 2. ditrans-polycis-prenols, such as the bacteria prenol and betulaprenol types. In general, bacteria, as all prokaryotic cells, possess ditrans-polycis-prenols containing between 10 and 12 units, the most abundant being undecaprenol (trivial name bactoprenol). Betulaprenols with n = 3-6 |
were isolated from the woody tissue of Betula verrucosa (Wellburn AR et al., Nature 1966, 212, 1364), and bacterial polyprenol with n = 8 were isolated from Lactobacillus plantarum (Gough DP et al., Biochem J 1970, 118, 167). Betulaprenol-like species |
with 14 to 22 isoprene units have been discovered in leaves of Ginkgo biloba (Ibata K et al., Biochem J 1983, 213, 305). Polyisoprenoid alcohols are accumulated in the cells most often as free alcohols and/or esters with carboxylic acids. |
A fraction of polyisoprenoid phosphates has also been detected, and this form is sometimes predominant in dividing cells and Saccharomyces cerevisiae (Adair WL et al., Arch Biochem Biophys 1987, 259, 589). - 3. tritrans-polycis-prenols, of the ficaprenol type.Some of the |
earliest samples were obtained from Ficus elastica, giving rise to the trivial names ficaprenol-11 and ficaprenol-12 (Stone KJ et al. Biochem J 1967, 102, 325). In plants, the diversity of polyprenols is much broader, their chain length covers the broad |
spectrum of compounds ranging from 6 up to 130 carbon atoms (Rezanka T et al., J Chromatogr A 2001, 936, 95). - 4. dolichol types, the a terminal is saturated. Most eukaryotic cells contain one type of polyisoprenoid alcohols with |
one a-saturated isoprenoid unit (2,3-dihydro polycis-prenols) which have been called dolichol by Pennock JF et al. (Nature 1960, 186, 470), a derivative of prenols. Most of these carry two trans units at the w-end of the chain. Dolichols (fro the |
Greek dolikos: long) have the general structure : Dolichols isolated from yeast or animal cells consist mainly of seven to eight compounds, those with 16, 18, or 19 isoprenoid units being the most abundant (Ragg SS, Biochem Biophys Res Comm |
1998, 243, 1). Dolichol amount was shown to be increased in the brain gray matter of elderly (Pullarkat RK et al., J Biol Chem 1982, 257, 5991). Dolichols with 19, 22 and 23 isoprenoid units were described as early as |
1972 in marine invertebrates (Walton MJ et al., Biochem J 1972, 127, 471). Furthermore, the pattern of their distribution may be considered as a chemotaxonomic criterion. It has been reported that a high proportion of dolichols is esterified to fatty |
acids. As an example, 85-90% of dolichols are esterified in mouse testis (Potter J et al., Biochem Biophys Res Comm 1983, 110, 512). In addition, dolichyl dolichoate has been found in bovine thyroid (Steen L. et al., Biochim Biophys Acta, |
1984, 796, 294). They are well known for their important role as glycosyl carrier in a phosphorylated form in the synthesis of polysaccharides and glycoproteins in yeast cells, and animals. Dolichyl phosphate is an obligatory intermediate in the biosynthesis of |
N-glycosidically linked oligosaccharide chains. Conversely, they have been identified as the predominant isoprenoid form in roots (Skorupinska-Tudek K et al., Lipids 2003, 38, 981) and in mushroom tissue (Wojtas M et al., Chem Phys Lipids 2004, 130, 109). Similar compounds |
(ficaprenols) have the same metabolic function in plants. The repartition of the various types of polyisoprenoid alcohols between plants and animals and their metabolism have been extensively discussed (Swiezewska E et al., Prog Lipid Res 2005, 44, 235). Biosynthesis of |
polyisoprenoid alcohols and their biological role have been reviewed in 2005 (Swiezewska E et al., Prog Lipid Res 2005, 44, 235). 3 - Phenolic alcohols Among the simple phenolic alcohols, monolignols are the source materials for biosynthesis of both lignans |
and lignin. The starting material for production of monolignols (phenylpropanoid) is the amino acid phenylalanine. There are two main monolignols: coniferyl alcohol and sinapyl alcohol. Para-coumaryl alcohol is similar to conipheryl alcohol but without the methoxy group. Conipheryl alcohol is |
found in both gymnosperm and angiosperm plants. Sinapyl alcohol and para-coumaryl alcohol, the other two lignin monomers, are found in angiosperm plants and grasses. Conipheryl esters (conypheryl 8-methylnonanoate) have been described in the fruits of the pepper, Capsicum baccatum (Kobata |
K et al., Phytochemistry 2008, 69, 1179). These compounds displayed an agonist activity for transient receptor potential vanilloid 1 (capsaicin receptor) as the well known capsaicinoids present in these plant species. Complex phenolic alcohols (phenolphthiocerol) were shown to be components |
of Mycobacterium glycolipids which are termed glycosides of phenolphthiocerol dimycocerosate (Smith DW et al., Nature 1960, 186, 887) belonging to the large family of "mycosides". The chain length differs according to the homologues, 18 and 20 carbon atoms in mycosides |
A, and B, respectively. One of these phenolphthiocerols is shown below. An analogue component but with a ketone group instead of the methoxy group, a phenolphthiodiolone, has been detected in mycoside A (Fournie JJ et al., J Biol Chem 1987, |
262, 3174). An alcohol with a furan group, identified as 3-(4-methylfuran-3-yl)propan-1-ol, has been isolated from a fungal endophyte living in a plant, Setaria viridis (Nakajima H et al., J Agric Food Chem 2010, 58, 2882). That compound was found to |
have a repellent effect on an insect, Eysarcoris viridis, which is a major pest of rice. Some cyclic alkyl polyols have been reported in plants. Among the various form present in an Anacardiaceae, Tapirira guianensis, from South America, two displayed |
anti-protozoal (Plasmodium falciparum) and anti-bacterial (Staphylococcus spp) activities (Roumy V et al., Phytochemistry 2009, 70, 305). The structure shown below is that of a trihydroxy-alcohol containing a cyclohexene ring. As emphasized by the authors, external application of the active plant |
extract or of the purified compounds could represent an accessible therapeutic alternative to classical medicine against leishmaniasis. aldehydes are found in free form, but also in the form of vinyl ether (known as alk-1-enyl ether) integated in glycerides and phospholipids |
(plasmalogens). The free aldehydes can be as fatty acids saturated or unsaturated. They have a general formula CH3(CH2)nCHO with n=6 to 20 or greater. The most common is palmitaldehyde (hexadecanal) with a 16 carbon chain. Normal monoenoic aldehydes are analogous |
to the monoenoic fatty acids. It must be noticed that an aldehyde function may be found at a terminal (w) position while an acid function is present at the other end of the carbon chain (oxo fatty acids). These compounds |
have important signaling properties in plants. Long-chain aldehydes have been described in the waxes which impregnate the matrix covering all organs of plants (Vermeer CP et al., Phytochemistry 2003, 62, 433). These compounds forming about 7% of the leaf cuticular |
waxes of Ricinus communis were identified as homologous unbranched aldehydes ranging from C22 to C28 with a hydroxyl group at the carbon 3. Long-chain 5-hydroxyaldehydes with chain lengths from C24 to C36, the C28 chain being the most abundant, were |
identified in the cuticular wax of Taxus baccata needles (Wen M et al., Phytochemistry 2007, 68, 2563). Long-chain aliphatic aldehydes with chain-length from C22 to C30 are also present in virgin olive oils, hexacosanal (C26) being the most abundant aldehyde |
(Perez-Camino MC et al., Food Chem 2012, 132, 1451). Aldehydes may be produced during decomposition of fatty acid hydroperoxides following a peroxidation attack. Several aldehydes (hexanal, heptanal..) belong to aroma compounds which are found in environmental or food systems (see |
the website: Flavornet). Aldehydes (mono- or di-unsaturated) with 5 to 9 carbon atoms are produced by mosses (Bryophyta) after mechanical wounding (Croisier E et al., Phytochemistry 2010, 71, 574). It was shown that they were produced by oxidative fragmentation of |
polyunsaturated fatty acids (C18, C20). Trans-2-nonenal is an unsaturated aldehyde with an unpleasant odor generated during the peroxidation of polyunsaturated fatty acids. It participates to body odor and is found mainly covalently bound to protein in vivo (Ishino K et |
al., J Biol Chem 2010, 285, 15302). Fatty aldehydes may be determined easily by TLC or gas liquid chromatography (follow that link). The most common method for the determination of aldehydes involves derivatization with an acidic solution of 2,4-dinitrophenylhydrazine to |
form corresponding hydrazones followed by HPLC separation and UV–VIS detection. An optimized derivatization procedure for the determination of aliphatic C1-C10 aldehydes has been described (Stafiej A et al., J Biochem Biophys Meth 2006, 69, 15). Other short-chain aldehydes (octadienal, octatrienal, |
heptadienal) are produced via a lipoxygenase-mediated pathway from polyunsaturated fatty acids esterifying glycolipids in marine diatoms (D'Ippolito G et al., Biochim Biophys Acta 2004, 1686, 100). Heighteen species of diatoms have been shown to release unsaturated aldehydes (C7:2, C8:2, C8:3, |
C10:2, and C10:3) upon cell disruption (Wichard T et al., J Chem Ecol 2005, 31, 949). Several short-chain aldehydes were shown to induce deleterious effects on zooplankton crustaceans and thus limiting the water secondary production (birth-control aldehydes) (D'Ippolito G et |
al., Tetrahedron Lett 2002, 43, 6133). In laboratory experiments, three decatrienal isomers produced by various diatoms were shown to arrest embryonic development in copepod and sea urchins and have antiproliferative and apoptotic effects on carcinoma cells (Miralto A et al., |
Nature 1999, 402, 173). Later, the copepod recruitment in blooms of planktonic diatom was shown to be suppressed by ingestion of dinoflagellate aldehydes (Nature 2004, 429, 403). It was demonstrated that diatoms can accurately sense a potent 2E,4E/Z-decadienal and employ |
it as a signaling molecule to control diatom population sizes (Vardi A et al., PLoS Biol 2006, 4, e60). This aldehyde triggered a dose-dependent calcium transient that has derived from intracellular store. Subsequently, calcium increase led to nitric oxide (NO) |
generation by a calcium-dependent NO synthase-like activity, resulting in cell death in diatoms. Myeloperoxidase-derived chlorinated aldehydes with plasmalogens has been reported. Thus, the vinyl-ether bond of plasmalogens is susceptible to attack by HOCl to yield a lysophospholipid and an Both |
these chloro-fatty aldehydes have been detected in neutrophils activated with PMA (Thukkani AK et al., J Biol Chem 2002, 277, 3842) and in human atherosclerotic AK et al., Circulation 2003, 108, 3128). Furthermore, 2-chlorohexadecanal was shown to induce COX-2 expression |
in human coronary artery endothelial cells (Messner MC et al., Lipids 2008, 43, 581). These data suggest that 2-chlorohexadecanal and possibly its metabolite 2-chlorohexadecanoic acid, both produced during leukocyte activation, may alter vascular endothelial cell function by upregulation of COX-2 |
expression. Long after the demonstration of the presence of iodinated lipids in thyroid (besides iodinated aminoacids), it was shown that the major iodinated lipid formed in thyroid when incubated in vitro with iodide was 2-iodohexadecanal (Pereira A et al, J |
Biol Chem 1990, 265, 17018). In rat and dog thyroid, 2-iodooctadecanal was determined to be more abundant that the 16-carbon aldehyde. These compounds, which are thought to play a role in the regulation of thyroid function, were recently shown to |
be formed by the attack of reactive iodine on the vinyl ether group of PE plasmalogen. This attack generates an unstable iodinated derivative which breaks into lysophosphatidylethanolamine and 2-iodo aldehydes (Panneels V et al, J Biol Chem 1996, 271, 23006). |
In some bacteria, aldehyde analogs of cyclopropane fatty acids were described. Several fatty aldehydes are known to have pheromone functions. Studies in African and Asian countries have shown that the use of 10,12-hexadecadienal could be effective for control of the |
spiny bollworm Earias insulana, a cotton pest. The sex pheromone of the navel orange worm, Amyelois transitella, 11,13-hexadecadienal, is usually used in the control of this citric pest. A branched saturated aldehyde (3,5,9-trimethyldodecenal, stylopsal) has been identified as a female-produced |
sex pheromone in Stylops (Strepsiptera), an entomophagous endoparasitic insect (Cvacka J et al., J Chem Ecol 2012, 38, 1483). Several isoprenoid aldehydes are important in insect biology as pheromones and in botany as volatile odorous substances. Some examples are given |
below: These three terpenic aldehydes are produced in large amounts by the mandibular glands of ants and may function as defensive repellents (Regnier FE et al., J Insect Physiol 1968, 14, 955). In contrast, the same molecules have a role |
of recruiting pheromones in honeybees Citral, a mixture of the tautomers geranial (trans-citral) and neral (cis-citral) is a major component (more than 60%) of the lemongrass (Cymbopogon flexuosus) oil. Lemongrass is widely used, particularly in Southeast Asia and Brazil, as |
a food flavoring, as a perfume, and for its medicinal properties (analgesic and anti-inflammatory). It was found that citral is a major suppressor of COX-2 expression and an activator of PPARa and g (Katsukawa M et al., Biochim Biophys Acta |
2010, 1801, 1214). It was demonstrated that damaged leaves released 2-hexenal, among other C6-volatile aldehydes, produced from the catalytic activity of hydroperoxide lyase (Turlings TC et al., Proc Ntl Acad Sci USA 1995, 92, 4169). These compounds, considered as signal |
molecules, can trigger several responses in neighboring plants and may also act as antimicrobial agents (Farmer EE, Nature 2001, 411, 854). One important constituent of this group of aldehydes is retinal, one active form of vitamin A involved in the |
light reception of animal eyes but also in bacteria as a component of the proton pump. Retinal exist in two forms, a cis and a trans isomer. On illumination with white light, the visual pigment, rhodopsin is converted to a |
mixture of a protein (opsin) and trans-retinal. This isomer must be transformed into the cis form by retinal isomerase before it combines again with opsin (dark phase). Both isomers can be reduced to retinol (vitamin A) by a NADH dependent |
alcohol dehydrogenase. Retinol is stocked in retina mainly in an acylated form. Cinnamic aldehyde (cinnamaldehyde) is the key flavor compound in cinnamon essential oil extracted from Cinnamomum zeylanicum and Cinnamomum cassia bark. Investigations have revealed than that benzyl aldehyde activates |
the Nrf2-dependent antioxidant response in human epithelial colon cells (Wondrak GT et al., Molecules 2010, 15, 3338). Cinnamic aldehyde may therefore represent a precious chemopreventive dietary factor targeting colorectal carcinogenesis. |
The immune system immune; immunity; disease; bacteria; viruses; white; cells; lymph; germs; mucous; mucus; glands; What is immunity? Immunity (say im-yoon-it-i) means that you are protected against something. There are different kinds of immunity. This topic is about how different parts of our bodies work together to k... |
are born. Immunisation (having your 'shots') helps our body's immune defence system protect us from diseases . body's immune system Every body has an inbuilt immune system which protects it from diseases and germs. This system has a lot of different parts which work together to keep out any harmful germs, and attack an... |
Every day your body is exposed to millions of germs, and you do not get sick from them because of your immune system. - Every time you do get sick because of a germ, your immune system works to get rid of it and then it remembers how to fight the infection if the same germ comes again. - Usually the older you get, |
the more germs you become immune to. So, let's have a look at the immune system, starting from the outside of the body. The skin is the first line of defence in your immune system. You know how you put plastic wrap over leftovers to keep them fresh enough for later? Well, your skin is like a plastic wrap to keep germs ... |
into your body. - The epidermis (outside layer of skin) has special cells which warn the body about incoming germs. - Glands in the skin also make substances that can kill some bacteria (anti-bacterial chemicals). This means you don't get infections on your skin unless your skin is damaged, such as by a cut or a graze.... |
next point of attack. - The mucous membranes which line the mouth, throat, lungs and bowel, act like a barrier to germs, just as the skin does. - Saliva in the mouth and the tears which wash your eyes have special enzymes (chemicals) in them which break down the cell walls of many bacteria and viruses. - The mucous tha... |
nose, throat and lungs traps bacteria, viruses and dust. - Acid in your stomach kills most germs, and starts to digest your food. - Lymph (limf) is a clear fluid that is very similar to blood plasma, the clear liquid in blood, but it carries only white blood cells, not red blood cells. - The lymph flows through all the... |
picking up fluid around cells and carrying it back to large veins near the heart. It also carries white blood cells to the places that they are needed. - Some bacteria or viruses that have entered the body are collected by the lymph and passed on to the lymph nodes where they are filtered out and destroyed. Lymph nodes... |
doctor can often tell if you have an infection by checking out the lymph nodes (glands) in your neck and under your arms to see if they're swollen. If they are, it shows that they are working to get rid of bacteria or viruses. In your blood you have red blood cells and white blood cells, and in lymph there are white bl... |
There are several different types of white cells which work together to seek out and destroy bacteria and viruses. All of them start off in the bone marrow, growing from 'stem cells'. The disease-fighting white blood cells are specialists. Some of the white blood cells are: - Neutrophils (say new-tro-fills), which move... |
that don't belong in your body). - Macrophages (say mak-row-far-jes) are the biggest blood cells. Some live in different parts of the body and help to keep it clean, eg. in the lungs. Others swim around cleaning up other white blood cells that have been damaged while doing their jobs, eg. cleaning up pus that has been ... |
clear out bacteria from a wound. - Lymphocytes (say lim-fo-sites) work on bacterial and viral infections There are two different types: - B cells produce antibodies. Each cell watches out for a particular germ, and when that germ arrives, the cell starts to produce more antibodies which begin the process of killing tha... |
can recognise that these germs need to be destroyed. - T cells look for cells in your body that are hiding invaders (germs) or body cells that are different to normal healthy cells (such as cells that could develop into a cancer) and kill them. does your immune system know which cells to attack? Your body has lots of f... |
help your body work properly - eg. some bacteria inside your bowel help you to digest your food and break it up into the different things that are needed in various parts of the body. - These friendly bacteria live on the surfaces of the body, such as on our skin or inside the bowel. - They do not try to invade the bod... |
so the immune system does not try to get rid of them. - Other germs which cause illness, try to enter the body. - Antibodies, which are made by the lymphocytes, attach to the invaders so that the other white blood cells can destroy them. They 'tag' them so they can be easily noticed. As well as attacking germs, your im... |
destroys other cells which do not belong in your body. - The cells in your own body are marked with a special system called Human Leukocyte Antigen or HLA (say Hew-man lew-ko-site anti-jen). - Your immune system can recognise these markings as 'you'. Any cells which do not have the right markings are 'not you' and are ... |
have a blood transfusion with the wrong types of blood cells. Your body's immune system recognises that these cells do not belong in your body, so it destroys them. How you know your immune system is working You know your immune system is working: - if you get better after you are sick - if cuts heal without getting in... |
catch the same diseases over and over again - when you get swollen glands - when you get swelling and soreness around a cut. Your immune system is in there working to get rid of any infection. When things go wrong with the immune system Sometimes the immune system will make a mistake. - It may attack your own body as i... |
the enemy, eg. insulin dependent diabetes (the type that most often starts in children and young people) is caused by the immune system attacking the cells in the pancreas that make insulin. - Allergies are caused by the immune system over-reacting to something that is not really a threat, like when pollen triggers hay... |
person to another - eg. a skin or organ transplant - then the immune system will attack the new part. The immune system has to be suppressed by drugs to allow the transplant to work. - When the immune system is damaged, such as when people have a serious illness called AIDS, they get lots of infections and are much mor... |
cancers. Their body cannot recognise the infection or abnormal cells very well and the immune system does not destroy them as well as usual. The immune system is absolutely amazing. It deals with millions of bacteria and viruses every day to keep us healthy. Keeping up to date with immunisations can help your body to b... |
this information to help you to understand important things about staying healthy and happy. However, if you feel sick or unhappy, it is important to tell your mum or dad, a teacher or another grown-up. |
Radon, a silent killer in homes DeKALB – Many homeowners take precautions to protect themselves. They lock their doors at night, turn off and unplug appliances and regularly test their |
smoke detectors. Radon isn’t something many homeowners consider a danger in their homes, but it could be harming them the most. Radon is a colorless, odorless naturally occurring gas found |
in uranium in soil. The gas often seeps through cracks in a house’s foundation or other areas exposed to soil. The health risks associated with radon are not immediate but |
rather a result of continuous exposure over a long period of time. If you have any technical difficulties, either with your username and password or with the payment options, please |
When it comes to solar power, the real dilemmas are efficiency and cost. On the one hand, efficiency has steadily improved over the last couple decades to the point where it’s approaching the utility prices of other power generation methods. |
Exotic technologies promise even greater gains. However, the price of solar-generated power still remains at least five times as expensive as coal-power, the chief source of power in the U.S. (compared to the leading candidate, nuclear, which is approximately 1.5 |
to 2 times as expensive). While solar adoption from a cost standpoint is unattractive, there's much debate over whether commercial adoption is needed to spur further research to propel solar into the realm of cost competitiveness. While many nations like |
the U.S. and China have modestly taken this position, adopting solar at a moderate rate, one nation has fallen head over heels for solar -- Spain. Spain is allowing solar and wind power plants to charge as much as 10 |
times the rates of coal power plants, making it possible for solar power installations to earn utilities big money. On average, recent rate increases have raised solar charges to over 7 times the rates of coal or natural gas rates. |
The costs are added onto consumers' power bills. The results are mixed; while Spanish power bills are at record highs, the number of deployments is soaring. Spain has 14 GW of solar power, or the equivalent capacity of nine average |
nuclear reactors, under construction -- the most of any nation. Florida’s FPL Group Inc. and French Electricite de France SA are among the many jumping to build in Spain. Gabriel Calzada, an economist and professor at Rey Juan Carlos University |
in Madrid, states, "Who wouldn’t want to enter a business that’s paid many times more than the market rate, and where the customer is guaranteed for life?" By 2009, 42 percent of Spaniards energy bills -- approximately 95 euros ($127) |
on average -- will be provided by alternative energy. Spanish law requires power distributors to buy all clean energy produced in the first 25 years of the plants' lives. The government also recently raised the rate of Spain believes this |
sacrifice will pay off as fossil fuel resources become depleted and emissions standards tighten. Karsten von Blumenthal, an industrial analyst at Hamburg-based SES Research GmbH states, "The guarantee is more attractive than what other countries offer. Actually the U.S. has |
better space for solar, in the deserts of California and Nevada." The U.S. meanwhile is also advancing thanks in part to President Obama's solar initiatives passed earlier this year as part of the federal stimulus legislation. Over 6 GW of |
capacity is planned for the U.S. Fred Morse, an official at the Washington- based Solar Energy Industries Association trade group and author of the first report to the White House on solar power (1969), says that the U.S. needs to |
adopt more incentives if it hopes to catch Spain. He states, "The incentives, if implemented promptly and effectively, should greatly facilitate the financing of these plants." One promising benefit of the Spanish solar boom is that it is increasing the |
number of plants utilizing new, potentially more efficient technologies like solar thermal or sterling engines. Spain is limiting the number of photovoltaic plants (solar panel-based designs), but is giving out unlimited licenses for solar thermal and other alternative plants. quote: |
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