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Farnesene
The term farnesene refers to a set of six closely related chemical compounds which all are sesquiterpenes. α-Farnesene and β-farnesene are isomers, differing by the location of one double bond. α-Farnesene is 3,7,11-trimethyl-1,3,6,10-dodecatetraene and β-farnesene is 7,11-dimethyl-3-methylene-1,6,10-dodecatriene. The alpha form can exist as four stereoisomers that differ about the geometry of two of its three internal double bonds (the stereoisomers of the third internal double bond are identical). The beta isomer exists as two stereoisomers about the geometry of its central double bond. Two of the α-farnesene stereoisomers are reported to occur in nature. (''E'',''E'')-α-Farnesene is the most common isomer. It is found in the coating of apples, and other fruits, and it is responsible for the characteristic green apple odour. Its oxidation by air forms compounds that are damaging to the fruit. The oxidation products injure cell membranes which eventually causes cell dea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Farnesol
Farnesol is a natural 15-carbon organic compound which is an acyclic sesquiterpene alcohol. Under standard conditions, it is a colorless liquid. It is hydrophobic, and thus insoluble in water, but miscible with oils. As the pyrophosphate ester, farnesol is a precursor to many terpenes and terpenoids. Uses Farnesol is present in many essential oils such as citronella oil, citronella, neroli, cyclamen, lemon grass, tuberose, rose, musk, balsam, and Tolu balsam, tolu. It is used in perfumery to emphasize the odors of sweet, floral perfumes. It enhances perfume scent by acting as a co-solvent that regulates the volatility of the odorants. It is especially used in lilac and peony perfumes. Farnesol and its ester derivatives are important organic synthesis, precursors for a variety of other compounds used as fragrances and vitamins. Cosmetics Farnesol is used as a deodorant in cosmetic products. Farnesol is subject to restrictions on its use in perfumery, because some people may beco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aphid
Aphids are small sap-sucking insects in the Taxonomic rank, family Aphididae. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white Eriosomatinae, woolly aphids. A typical life cycle involves flightless females giving Viviparity, live birth to female Nymph (biology), nymphs—who may also be already Pregnancy, pregnant, an adaptation scientists call telescoping generations—without the involvement of males. Developmental biology, Maturing rapidly, females breed profusely so that the number of these insects multiplies quickly. Alate, Winged females may develop later in the season, allowing the insects to colonize new plants. In Temperate climate, temperate regions, a phase of sexual reproduction occurs in the autumn, with the insects often overwintering as eggs. The life cycle of some species involves an alternation between two species of host plants, for example between an annual crop and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Codling Moth
The codling moth (''Cydia pomonella'') is a member of the Lepidopteran family Tortricidae. They are major pests to agricultural crops, mainly fruits such as apples and pears, and a codling moth larva is often called an " apple worm". Along with the apple maggot, it is the worm that people encounter when biting into an infected apple. Because the larvae are not able to feed on leaves, they are highly dependent on fruits as a food source and thus have a significant impact on crops. The caterpillars bore into fruit and stop it from growing, which leads to premature ripening. Various means of control, including chemical, biological, and preventive, have been implemented. This moth has a widespread distribution, being found on six continents. Adaptive behavior such as diapause and multiple generations per breeding season have allowed this moth to persist even during years of bad climatic conditions. Geographic distribution Although the geographic origin of codling moths is uncl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sesquiterpene
Sesquiterpenes are a class of terpenes that consist of three isoprene units and often have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be cyclic or contain rings, including many combinations. Biochemical modifications such as oxidation or rearrangement produce the related sesquiterpenoids. It is estimated (2006) that 3000 sesquiterpenes have been identified. Biosynthesis and examples The reaction of geranyl pyrophosphate with isopentenyl pyrophosphate results in the 15-carbon farnesyl pyrophosphate (FPP), which is an intermediate in the biosynthesis of sesquiterpenes such as farnesene. Cyclic sesquiterpenes are more common than cyclic monoterpenes because of the increased chain length and additional double bond in the sesquiterpene precursors. In addition to common six-membered ring systems such as the ones found in zingiberene and bisacurone, cyclization of one end of the chain to the other end can lead to macrocyclic rings such as humulene. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perfume Ingredients
Perfume (, ) is a mixture of fragrant essential oils or aroma compounds (fragrances), fixatives and solvents, usually in liquid form, used to give the human body, animals, food, objects, and living-spaces an agreeable scent. Perfumes can be defined as substances that emit and diffuse a pleasant and fragrant odor. They consist of artificial mixtures of aromatic chemicals and essential oils. The 1939 Nobel Laureate for Chemistry, Leopold Ružička stated in 1945 that "right from the earliest days of scientific chemistry up to the present time, perfumes have substantially contributed to the development of organic chemistry as regards methods, systematic classification, and theory." Ancient texts and archaeological excavations show the use of perfumes in some of the earliest human civilizations. Modern perfumery began in the late 19th century with the commercial synthesis of aroma compounds such as vanillin and coumarin, which allowed for the composition of perfumes with sme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insect Pheromones
Insect pheromones are neurotransmitters that serve the chemical communication between individuals of an insect species. They thus differ from kairomones, in other words, neurotransmitters that transmit information to non-species organisms. Insects produce pheromones in special glands and release them into the environment. In the pheromone receptors of the sensory cells of the recipient, they produce a nerve Stimulus (physiology), stimulus even in very low concentrations, which ultimately leads to a behavioral response. Biological specificity, Intraspecific communication of insects via these substances takes place in a variety of ways and serves, among other things, to find sexual partner, to maintain harmony in a Colony (biology), colony of Eusociality, socially living insects, to mark territories or to find nest sites and food sources. In 1959, the German biochemist and Nobel Prize winner Adolf Butenandt identified and synthesized the Saturated and unsaturated compounds, unsatura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terpene
Terpenes () are a class of natural products consisting of compounds with the formula (C5H8)n for n ≥ 2. Terpenes are major biosynthetic building blocks. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly Pinophyta, conifers. In plants, terpenes and terpenoids are important mediators of ecological biological interaction, interactions, while some insects use some terpenes as a form of defense. Other functions of terpenoids include cell growth modulation and plant elongation, light harvesting and photoprotection, and membrane permeability and fluidity control. Terpenes are classified by the number of carbons: monoterpenes (C10), sesquiterpenes (C15), diterpenes (C20), as examples. The terpene alpha-pinene is a major component of the common solvent, turpentine. The one terpene that has major applications is natural rubber (i.e., polyisoprene). The possibility that other terpenes could be used as precursors to pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prenylation
Prenylation (also known as isoprenylation or lipidation) is the addition of hydrophobic molecules to a protein or a biomolecule. It is usually assumed that prenyl groups (3-methylbut-2-en-1-yl) facilitate attachment to cell membranes, similar to lipid anchors like the GPI anchor, though direct evidence of this has not been observed. Prenyl groups (also called isoprenyl groups, having one hydrogen atom more than isoprene) have been shown to be important for protein–protein binding through specialized prenyl-binding domains. Protein prenylation Protein prenylation involves the transfer of either a farnesyl or a geranylgeranyl moiety to C-terminal cysteine(s) of the target protein. There are three enzymes that carry out prenylation in the cell, farnesyl transferase, Caax protease and geranylgeranyl transferase I. Farnesylation is a type of prenylation, a post-translational modification of proteins by which an isoprenyl group is added to a cysteine residue. It is an important ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerolidol
Nerolidol, also known as peruviol and penetrol , is a naturally occurring sesquiterpene alcohol. A colorless liquid, it is found in the essential oils of many types of plants and flowers. There are four isomers of nerolidol', which differ in the geometry about the central double bond and configuration of the hydroxyl-bearing carbon, but most applications use such a mixture. The aroma of nerolidol is woody and reminiscent of fresh bark. It is used as a flavoring agent and in perfumery as well as in non-cosmetic products such as detergents and cleansers. Nerolidyl derivatives include nerolidyl diphosphate and the fragrance nerolidyl acetate. Synthesis and occurrence Nerolidol is produced commercially from geranylacetone, e.g., by the addition of vinyl Grignard reagent. It is used as a source of farnesol, vitamin E, and vitamin K1. Significant sources of natural nerolidol is Cabreuva oil and the oil of ''Dalbergia parviflora''. It is also present in neroli, ginger, jasmine, lave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insect Repellent
An insect repellent (also commonly called "bug spray" or "bug deterrent") is a substance applied to the skin, clothing, or other surfaces to discourage insects (and arthropods in general) from landing or climbing on that surface. Insect repellents help prevent and control the outbreak of insect-borne (and other arthropod-bourne) diseases such as malaria, Lyme disease, dengue fever, bubonic plague, river blindness, and West Nile fever. Pest animals commonly serving as vectors for disease include insects such as flea, fly, and mosquito; and ticks (arachnids). Some insect repellents are insecticides (bug killers), but most simply discourage insects and send them flying or crawling away. Effectiveness Synthetic repellents tend to be more effective and/or longer lasting than "natural" repellents. For protection against ticks and mosquito bites, the U.S. Centers for Disease Control (CDC) recommends DEET, icaridin (picaridin, KBR 3023), oil of lemon eucalyptus (OLE), para-me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potato
The potato () is a starchy tuberous vegetable native to the Americas that is consumed as a staple food in many parts of the world. Potatoes are underground stem tubers of the plant ''Solanum tuberosum'', a perennial in the nightshade family Solanaceae. Wild potato species can be found from the southern United States to southern Chile. Genetic studies show that the cultivated potato has a single origin, in the area of present-day southern Peru and extreme northwestern Bolivia. Potatoes were domesticated there about 7,000–10,000 years ago from a species in the '' S. brevicaule'' complex. Many varieties of the potato are cultivated in the Andes region of South America, where the species is indigenous. The Spanish introduced potatoes to Europe in the second half of the 16th century from the Americas. They are a staple food in many parts of the world and an integral part of much of the world's food supply. Following millennia of selective breeding, there are now over 5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
