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Antifeedant
Antifeedants are organic compounds produced by plants to repel herbivores through distaste or toxicity. These chemical compounds are typically classified as secondary metabolites in that they are not essential for the metabolism of the plant, but instead confer longevity. Antifeedants exhibit a wide range of activities and chemical structures as biopesticides. Examples include rosin, which inhibits attack on trees, and many alkaloids, which are highly toxic to specific insect species, such as quassinoids (extracts from ''Quassia'' trees) against the diamondback moth ('' Plutela xylostella''). ''Samadera indica'' also has quassinoids used for insect antifeedant uses. History "Plant-derived insecticides (e.g., rotenone, veratridines, pyrethrins, and nicotine) have been used for insect control since antiquity." The active ingredients in these plants have been purified and modified. For example, variations on pyrethrin have spawned a large number of synthetic insecticides calle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Defense Against Herbivores
Plant defense against herbivory or host-plant resistance is a range of adaptations Evolution, evolved by plants which improve their fitness (biology), survival and reproduction by reducing the impact of herbivores. Many plants produce secondary metabolites, known as Heterotelergones, allelochemicals, that influence the behavior, growth, or survival of herbivores. These chemical defenses can act as repellents or toxins to herbivores or reduce plant digestibility. Another defensive strategy of plants is changing their attractiveness. Plant perception (physiology), Plants can sense being touched, and they can respond with strategies to defend against herbivores. Plants alter their appearance by changing their size or quality in a way that prevents overconsumption by large herbivores, reducing the rate at which they are consumed. Other defensive strategies used by plants include escaping or avoiding herbivores at any time in any placefor example, by growing in a location where plants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biopesticide
A biopesticide is a biological substance or organism that damages, kills, or repels organisms seens as pests. Biological pest management intervention involves predatory, parasitic, or chemical relationships. They are obtained from organisms including plants, bacteria and other microbes, fungi, nematodes, ''etc''. They are components of integrated pest management (IPM) programmes, and have received much practical attention as substitutes to synthetic chemical plant protection products (PPPs). Definitions Regulatory positions can be influenced by public perceptions, thus: * the EU, defines biopesticides as "a form of pesticide based on micro-organisms or natural products". * the US EPA states that they "include naturally occurring substances that control pests (biochemical pesticides), microorganisms that control pests (microbial pesticides), and pesticidal substances produced by plants containing added genetic material (plant-incorporated protectants) or PIPs". Types Biopesti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quassinoids
Quassinoids are degraded triterpene lactones (similar to limonoids) of the Simaroubaceae plant family grouped into C-18, C-19, C-20, C-22 and C-25 types. The prototypical member of the group, quassin, was first described in the 19th century from plants of the genus ''Quassia'' from which it gets its name. It was isolated in 1937, and its structure elucidated in 1961. Sources More than 200 currently-known quassinoids have been isolated and identified from various species of simaroubaceae family. Quassinoids can also be extracted from various Simaroubaceae family species such as; '' Ailanthus excelsa'', ''Ailanthus vilmoriniana'', (the fruits of) '' Brucea javanica'', '' Hannoa klaineana'', '' Pierreodendron kerstingii'', '' Quassia africana'', '' Quassia amara'', (the wood of ) '' Picrasma ailanthoides'', '' Picrasma javanica'', '' Picrolemma pseudocoffea'', '' Simaba guianensis'', and '' Simaruba glauca''. They are found in species from American and West African genera (belong ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucosinolates
Glucosinolates are natural components of many pungent plants such as mustard, cabbage, and horseradish. The pungency of those plants is due to mustard oils produced from glucosinolates when the plant material is chewed, cut, or otherwise damaged. These natural chemicals most likely contribute to plant defence against pests and diseases, and impart a characteristic bitter flavor property to cruciferous vegetables. Occurrence Glucosinolates occur as secondary metabolites of almost all plants of the order Brassicales. This includes the economically important family Brassicaceae as well as Capparaceae and Caricaceae. Outside of the Brassicales, the genera '' Drypetes'' and '' Putranjiva'' in the family Putranjivaceae, are the only other known occurrence of glucosinolates. Glucosinolates occur in various edible plants such as cabbage (white cabbage, Chinese cabbage, broccoli), Brussels sprouts, watercress, arugula, horseradish, capers, and radishes where the breakdo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amygdalin Structure
Amygdalin (from Ancient Greek: ' 'almond') is a naturally occurring chemical compound found in many plants, most notably in the seeds (kernels, pips or stones) of apricots, bitter almonds, apples, peaches, cherries and plums, and in the roots of manioc. 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 h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cruciferous Vegetables
Cruciferous vegetables are vegetables of the family Brassicaceae (also called Cruciferae) with many genera, species, and cultivars being raised for food production such as cauliflower, cabbage, kale, garden cress, bok choy, broccoli, Brussels sprouts, mustard plant and similar green leaf vegetables. The family takes its alternative name (Cruciferae, Neo-Latin for "cross-bearing") from the shape of their flowers, whose four petals resemble a cross. Ten of the most common cruciferous vegetables eaten by people, known colloquially in North America as cole crops and in the UK, Ireland and Australia as brassicas, are in a single species ('' Brassica oleracea''); they are not distinguished from one another taxonomically, only by horticultural category of cultivar groups. Numerous other genera, and species in the family are also edible. Cruciferous vegetables are one of the dominant food crops worldwide. They are best grown in temperatures between 15 to 21° C (59 to 70� ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Metabolites
Secondary metabolites, also called ''specialised metabolites'', ''secondary products'', or ''natural products'', are organic compounds produced by any lifeform, e.g. bacteria, archaea, fungi, animals, or plants, which are not directly involved in the normal growth, development, or reproduction of the organism. Instead, they generally mediate ecological interactions, which may produce a selective advantage for the organism by increasing its survivability or fecundity. Specific secondary metabolites are often restricted to a narrow set of species within a phylogenetic group. Secondary metabolites often play an important role in plant defense against herbivory and other interspecies defenses. Humans use secondary metabolites as medicines, flavourings, pigments, and recreational drugs. The term secondary metabolite was first coined by Albrecht Kossel, the 1910 Nobel Prize laureate for medicine and physiology. 30 years later a Polish botanist Friedrich Czapek described secondary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allyl Isothiocyanate
Allyl isothiocyanate (AITC) is a naturally occurring unsaturated isothiocyanate. The colorless oil is responsible for the pungent taste of cruciferous vegetables such as mustard, radish, horseradish, and wasabi. This pungency and the lachrymatory effect of AITC are mediated through the TRPA1 and TRPV1 ion channels. It is slightly soluble in water, but more soluble in most organic solvents. Biosynthesis and biological functions Allyl isothiocyanate can be obtained from the seeds of black mustard (''Rhamphospermum nigrum'') or brown Indian mustard (''Brassica juncea''). When these mustard seeds are broken, the enzyme myrosinase is released and acts on a glucosinolate known as sinigrin to give allyl isothiocyanate. This serves the plant as a defense against herbivores; since it is harmful to the plant itself, it is stored in the harmless form of the glucosinolate, separate from the myrosinase enzyme. When an animal chews the plant, the allyl isothiocyanate is released, repe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chrysanthemum
Chrysanthemums ( ), sometimes called mums or chrysanths, are flowering plants in the Asteraceae family. They are native to East Asia and northeastern Europe. Most species originate from East Asia, and the center of diversity is in China. Countless horticultural varieties and cultivars exist. Description The genus ''Chrysanthemum'' are perennial herbaceous flowering plants, sometimes subshrubs. The leaves are alternate, divided into leaflets and may be pinnatisect, lobed, or serrate (toothed) but rarely entire; they are connected to stalks with hairy bases. The compound inflorescence is an array of several flower heads, or sometimes a solitary head. The head has a base covered in layers of phyllaries. The simple row of ray florets is white, yellow, or red. The disc florets are yellow. Pollen grains are approximately 34 microns. The fruit is a ribbed achene. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tobacco Plant
''Nicotiana'' () is a genus of herbaceous plants and shrubs in the family Solanaceae, that is indigenous to the Americas, Australia, Southwestern Africa and the South Pacific. Various ''Nicotiana'' species, commonly referred to as tobacco plants, are cultivated as ornamental garden plants. '' N. tabacum'' is grown worldwide for the cultivation of tobacco leaves used for manufacturing and producing tobacco products, including cigars, cigarillos, cigarettes, chewing tobacco, dipping tobacco, snuff, and snus. Taxonomy Species The 79 accepted and known species include: * '' Nicotiana acuminata'' (Graham) Hook. – manyflower tobacco or many-flowered tobaccoKnapp et al. (2004) Nomenclatural changes and a new sectional classification in ''Nicotiana'' (Solanaceae) Taxon. 53 (1):73–82. * '' Nicotiana africana'' Merxm. * '' Nicotiana alata'' Link & Otto – jasmine tobacco, sweet tobacco, winged tobacco, Persian tobacco, ''tanbaku'' (in Persian) * '' Nicotiana attenuata'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alliin
Alliin is a sulfoxide that is a natural constituent of fresh garlic. It is a derivative of the amino acid cysteine. When fresh garlic is chopped or crushed, the enzyme alliinase converts alliin into allicin, which is responsible for the aroma of fresh garlic. Allicin and other thiosulfinates in garlic are unstable and form a number of other compounds, such as diallyl sulfide (DAS), diallyl disulfide (DADS) and diallyl trisulfide (DAT), dithiins and ajoene. Garlic powder is not a source of alliin, nor is fresh garlic upon maceration, since the enzymatic conversion to allicin takes place in the order of seconds. Alliin was the first natural product found to have both carbon- and sulfur-centered stereochemistry. Chemical synthesis The first reported synthesis, by Stoll and Seebeck in 1951, begins the alkylation of -cysteine with allyl bromide to form deoxyalliin. Oxidation of this sulfide with hydrogen peroxide gives both diastereomers of -alliin, differing in the orientat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Current Biology
''Current Biology'' is a biweekly peer-reviewed scientific journal that covers all areas of biology, especially molecular biology, cell biology, genetics, neurobiology, ecology, and evolutionary biology. The journal includes research articles, various types of review articles, as well as an editorial magazine section. The journal was established in 1991 by the Current Science group, was acquired by Elsevier in 1998, and has since 2001 been part of Cell Press, a subdivision of Elsevier. According to '' Journal Citation Reports'', the journal has a 2020 impact factor of 10.834. It was categorized as a "high impact journal" by the Superfund Research Program. References External links * Biology journals English-language journals Cell Press academic journals Academic journals established in 1991 Biweekly journals {{biology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
