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40-410: Resins protect plants from insects and pathogens, and are secreted in response to injury. Resins confound a wide range of herbivores, insects, and pathogens, while the volatile phenolic compounds may attract benefactors such as predators of insects that attack the plant. Most plant resins are composed of terpenes . Specific components are alpha-pinene , beta-pinene , delta-3 carene , and sabinene ,

80-562: A depside , and orcinol are found in lichen . The green alga Botryococcus braunii is the subject of research into the natural production of butylated hydroxytoluene (BHT), an antioxidant, food additive and industrial chemical. Phenolic acids such as protocatechuic , p-hydroxybenzoic , 2,3-dihydroxybenzoic , chlorogenic , vanillic , caffeic , p -coumaric and salicylic acid , cinnamic acid and hydroxybenzaldehydes such as p-hydroxybenzaldehyde , 3,4-dihydroxybenzaldehyde , vanillin have been isolated from in vitro culture of

120-411: A drop of a solvent such as acetone or chloroform is placed on it. African copal and the kauri gum of New Zealand are also procured in a semi-fossil condition. Rosin is a solidified resin from which the volatile terpenes have been removed by distillation. Typical rosin is a transparent or translucent mass, with a vitreous fracture and a faintly yellow or brown colour, non-odorous or having only

160-416: A new class of polyphenol. For example, ellagic acid is a dimer of gallic acid and forms the class of ellagitannins, or a catechin and a gallocatechin can combine to form the red compound theaflavin , a process that also results in the large class of brown thearubigins in tea. Two natural phenols from two different categories, for instance a flavonoid and a lignan, can combine to form a hybrid class like

200-450: A part of the visible spectrum is absorbed. The wavelengths left in the process (generally in red section of the spectrum) recompose the color of the particular substance. Acylation with cinnamic acids of anthocyanidins shifted color tonality (CIE Lab hue angle ) to purple . Here is a series of UV visible spectra of molecules classified from left to right according to their conjugation level: The absorbance pattern responsible for

240-624: A partial terpenoid structure). Methylations can occur by the formation of an ether bond on hydroxyl groups forming O-methylated polyphenols. In the case of the O-methylated flavone tangeritin , all of the five hydroxyls are methylated, leaving no free hydroxyls of the phenol group. Methylations can also occur on directly on a carbon of the benzene ring like in the case of poriol , a C-methylated flavonoid . The white rot fungus Phanerochaete chrysosporium can remove up to 80% of phenolic compounds from coking waste water. Tannins are used in

280-456: A slight turpentine odour and taste. Rosin is insoluble in water, mostly soluble in alcohol, essential oils , ether , and hot fatty oils. Rosin softens and melts when heated and burns with a bright but smoky flame. Rosin consists of a complex mixture of different substances including organic acids named the resin acids . Related to the terpenes, resin acid is oxidized terpenes. Resin acids dissolve in alkalis to form resin soaps , from which

320-591: Is 3,5-dihydroxy-4-isopropyl-trans-stilbene , a bacterial stilbenoid produced in Photorhabdus bacterial symbionts of Heterorhabditis nematodes. Phenolic acids can be found in mushroom basidiomycetes species. For example, protocatechuic acid and pyrocatechol are found in Agaricus bisporus as well as other phenylated substances like phenylacetic and phenylpyruvic acids . Other compounds like atromentin and thelephoric acid can also be isolated from fungi in

360-415: Is volumetric titration . An oxidizing agent, permanganate , is used to oxidize known concentrations of a standard solution, producing a standard curve . The content of the unknown phenols is then expressed as equivalents of the appropriate standard. Some methods for quantification of total phenolic content are based on colorimetric measurements. Total phenols (or antioxidant effect) can be measured using

400-453: Is a cognate of the Greek ῥητίνη rhētínē "resin of the pine", of unknown earlier origin, though probably non- Indo-European . The word "resin" has been applied in the modern world to nearly any component of a liquid that will set into a hard lacquer or enamel -like finish. An example is nail polish. Certain "casting resins" and synthetic resins (such as epoxy resin ) have also been given

440-469: Is a probe that is trapped within cells and is easily oxidized to fluorescent dichlorofluorescein (DCF). The method measures the ability of compounds to prevent the formation of DCF by 2,2'-Azobis(2-amidinopropane) dihydrochloride (ABAP)-generated peroxyl radicals in human hepatocarcinoma HepG2 cells. Other methods include butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), Rancimat method (rancidification assessment of fat). Larvae of

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480-790: Is a resin converted to epoxy glue upon the addition of a hardener. Silicones are often prepared from silicone resins via room temperature vulcanization . Alkyd resins are used in paints and varnishes and harden or cure by exposure to oxygen in the air. Natural phenol In biochemistry , naturally occurring phenols are natural products containing at least one phenol functional group . Phenolic compounds are produced by plants and microorganisms. Organisms sometimes synthesize phenolic compounds in response to ecological pressures such as pathogen and insect attack, UV radiation and wounding. As they are present in food consumed in human diets and in plants used in traditional medicine of several cultures, their role in human health and disease

520-424: Is a subject of research. Some phenols are germicidal and are used in formulating disinfectants. Various classification schemes can be applied. A commonly used scheme is based on the number of carbons and was devised by Jeffrey Harborne and Simmonds in 1964 and published in 1980: C 6 -C 7 -C 6 Diarylheptanoids are not included in this Harborne classification. They can also be classified on

560-452: Is correlated to the non-enzymatic browning color change characteristic of this process. This phenomenon can be observed in foods like carrot purees. Browning associated with oxidation of phenolic compounds has also been given as the cause of cells death in calli formed in in vitro cultures. Those phenolics originate both from explant tissues and from explant secretions. Phenolics are formed by three different biosynthetic pathways: (i)

600-694: Is used by honey bees to seal small gaps in their hives, while larger gaps are filled with beeswax. Shellac is an example of an insect-derived resin. Asphaltite and Utah resin are petroleum bitumens . Human use of plant resins has a very long history that was documented in ancient Greece by Theophrastus , in ancient Rome by Pliny the Elder , and especially in the resins known as frankincense and myrrh , prized in ancient Egypt . These were highly prized substances, and required as incense in some religious rites. The word resin comes from French resine , from Latin resina "resin", which either derives from or

640-822: The Agaricomycetes class. Orobol , an isoflavone , can be isolated from Aspergillus niger . Aromatic alcohols (example: tyrosol ) are produced by the yeast Candida albicans . They are also found in beer . These molecules are quorum sensing compounds for Saccharomyces cerevisiae . Aryl-alcohol dehydrogenase uses an aromatic alcohol and NAD to produce an aromatic aldehyde , NADH and H . Aryl-alcohol dehydrogenase (NADP+) uses an aromatic alcohol and NADP to produce an aromatic aldehyde , NADPH and H . Aryldialkylphosphatase (also known as organophosphorus hydrolase, phosphotriesterase, and paraoxon hydrolase) uses an aryl dialkyl phosphate and H 2 O to produce dialkyl phosphate and an aryl alcohol. Gyrophoric acid ,

680-596: The Aleppo Pine is used to flavour retsina , a Greek resinated wine . While animal resins are not as common as either plant or synthetic resins some animal resins like lac (obtained from Kerria lacca ) are used for applications like sealing wax in India , and lacquerware in Sri Lanka . Many materials are produced via the conversion of synthetic resins to solids. Important examples are bisphenol A diglycidyl ether , which

720-467: The Folin-Ciocalteu reaction . Results are typically expressed as gallic acid equivalents (GAE). Ferric chloride (FeCl 3 ) test is also a colorimetric assay. Lamaison and Carnet have designed a test for the determination of the total flavonoid content of a sample (AlCI 3 method). After proper mixing of the sample and the reagent, the mixture is incubated for 10 minutes at ambient temperature and

760-594: The Trolox equivalent antioxidant capacity (TEAC) assay. The reactivity of the various antioxidants tested are compared to that of Trolox , which is a vitamin E analog. Other antioxidant capacity assays that use Trolox as a standard include the diphenylpicrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC), ferric reducing ability of plasma (FRAP) assays or inhibition of copper-catalyzed in vitro human low-density lipoprotein oxidation. A cellular antioxidant activity (CAA) assay also exists. Dichlorofluorescin

800-548: The cyanobacterium Arthrospira maxima , used in the dietary supplement, Spirulina . The three cyanobacteria Microcystis aeruginosa , Cylindrospermopsis raciborskii and Oscillatoria sp. are the subject of research into the natural production of butylated hydroxytoluene (BHT), an antioxidant, food additive and industrial chemical. The proteobacterium Pseudomonas fluorescens produces phloroglucinol , phloroglucinol carboxylic acid and diacetylphloroglucinol . Another example of phenolics produced in proteobacteria

840-461: The flavonolignans . Nomenclature of polymers : Plants in the genus Humulus and Cannabis produce terpenophenolic metabolites, compounds that are meroterpenes . Phenolic lipids are long aliphatic chains bonded to a phenolic moiety. Many natural phenols are chiral . An example of such molecules is catechin . Cavicularin is an unusual macrocycle because it was the first compound isolated from nature displaying optical activity due to

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880-553: The shikimic acid pathway , is the common precursor of phenol containing amino acids and phenolic compounds. In plants, the phenolic units are esterified or methylated and are submitted to conjugation , which means that the natural phenols are mostly found in the glycoside form instead of the aglycone form. In olive oil, tyrosol forms esters with fatty acids. In rye, alkylresorcinols are phenolic lipids. Some acetylations involve terpenes like geraniol . Those molecules are called meroterpenes (a chemical compound having

920-501: The absorbance of the solution is read at 440 nm. Flavonoid content is expressed in mg/g of quercetin. Quantitation results produced by the means of diode array detector -coupled HPLC are generally given as relative rather than absolute values as there is a lack of commercially available standards for every phenolic molecules. The technique can also be coupled with mass spectrometry (for example, HPLC–DAD– ESI /MS) for more precise molecule identification . Other tests measure

960-421: The antioxidant capacity of a fraction. Some make use of the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation, which is reactive towards most antioxidants including phenolics, thiols and vitamin C . During this reaction, the blue ABTS radical cation is converted back to its colorless neutral form. The reaction may be monitored spectrophotometrically. This assay is often referred to as

1000-536: The basis of their number of phenol groups. They can therefore be called simple phenols or monophenols , with only one phenolic group, or di- ( bi- ), tri- and oligophenols , with two, three or several phenolic groups respectively. A diverse family natural phenols are the flavonoids , which include several thousand compounds, among them the flavonols , flavones , flavan-3ol ( catechins ), flavanones , anthocyanidins , and isoflavonoids . The phenolic unit can be found dimerized or further polymerized, creating

1040-410: The efficacy of the treatment. The recovery of natural phenols from biomass residue is part of biorefining . Studies on evaluating antioxidant capacity can use electrochemical methods. Detection can be made by recombinant luminescent bacterial sensors . Phenolic profiling can be achieved with liquid chromatography–mass spectrometry (LC/MS). A method for phenolic content quantification

1080-434: The family Dipterocarpaceae , dragon's blood from the dragon trees ( Dracaena species), elemi , frankincense from Boswellia sacra , galbanum from Ferula gummosa , gum guaiacum from the lignum vitae trees of the genus Guaiacum , kauri gum from trees of Agathis australis , hashish (Cannabis resin) from Cannabis indica , labdanum from mediterranean species of Cistus , mastic (plant resin) from

1120-399: The freshwater green alga Spongiochloris spongiosa . Pimaric acid Pimaric acid is a carboxylic acid from the resin acid group, often found in the oleoresins of pine trees. It can be prepared by dehydration of abietic acid , which it usually accompanies in mixtures like rosin . It is soluble in alcohols , acetone , and ethers . This article about an organic compound

1160-550: The insect. The phenolic biosynthetic and metabolic pathways and enzymes can be studied by means of transgenesis of genes. The Arabidopsis regulatory gene for production of Anthocyanin Pigment 1 (AtPAP1) can be expressed in other plant species. Phenols are found in the natural world, especially in the plant kingdom. Orobol can be found in Streptomyces neyagawaensis (an Actinobacterium). Phenolic compounds can be found in

1200-530: The mastic tree Pistacia lentiscus , myrrh from shrubs of Commiphora , sandarac resin from Tetraclinis articulata , the national tree of Malta, styrax (a Benzoin resin from various Styrax species) and spinifex resin from Australian grasses. Amber is fossil resin (also called resinite) from coniferous and other tree species. Copal, kauri gum, dammar and other resins may also be found as subfossil deposits. Subfossil copal can be distinguished from genuine fossil amber because it becomes tacky when

1240-458: The model animal Galleria mellonella , also called waxworms , can be used to test the antioxidant effect of individual molecules using boric acid in food to induce an oxidative stress. The content of malondialdehyde , an oxidative stress indicator, and activities of the antioxidant enzymes superoxide dismutase , catalase , glutathione S-transferase and glutathione peroxidase can be monitored. A pro phenoloxidase can also be recovered from

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1280-502: The monocyclic terpenes limonene and terpinolene , and smaller amounts of the tricyclic sesquiterpenes , longifolene , caryophyllene , and delta-cadinene . Some resins also contain a high proportion of resin acids . Rosins on the other hand are less volatile and consist of diterpenes among other compounds. Examples of plant resins include amber , Balm of Gilead , balsam , Canada balsam , copal from trees of Protium copal and Hymenaea courbaril , dammar gum from trees of

1320-687: The name "resin". Some naturally-derived resins, when soft, are known as 'oleoresins', and when containing benzoic acid or cinnamic acid they are called balsams. Oleoresins are naturally-occurring mixtures of an oil and a resin; they can be extracted from various plants. Other resinous products in their natural condition are a mix with gum or mucilaginous substances and known as gum resins . Several natural resins are used as ingredients in perfumes, e.g., balsams of Peru and tolu, elemi, styrax, and certain turpentines. Other liquid compounds found inside plants or exuded by plants, such as sap , latex , or mucilage , are sometimes confused with resin but are not

1360-445: The presence of planar chirality and axial chirality . Natural phenols show optical properties characteristic of benzene, e.g. absorption near 270 nm. According to Woodward's rules , bathochromic shifts often also happen suggesting the presence of delocalised π electrons arising from a conjugation between the benzene and vinyls groups. As molecules with higher conjugation levels undergo this bathochromic shift phenomenon,

1400-468: The red color of anthocyanins may be complementary to that of green chlorophyll in photosynthetically active tissues such as young Quercus coccifera leaves. Natural phenols are reactive species toward oxidation , notably the complex mixture of phenolics, found in food for example, can undergo autoxidation during the ageing process. Simple natural phenols can lead to the formation of B type proanthocyanidins in wines or in model solutions. This

1440-738: The resin acids are regenerated upon treatment with acids. Examples of resin acids are abietic acid (sylvic acid), C 20 H 30 O 2 , plicatic acid contained in cedar, and pimaric acid , C 20 H 30 O 2 , a constituent of galipot resin. Abietic acid can also be extracted from rosin by means of hot alcohol. Rosin is obtained from pines and some other plants , mostly conifers . Plant resins are generally produced as stem secretions, but in some Central and South American species of Dalechampia and Clusia they are produced as pollination rewards, and used by some stingless bee species in nest construction. Propolis , consisting largely of resins collected from plants such as poplars and conifers ,

1480-475: The same. Saps, in particular, serve a nutritive function that resins do not. Plant resins are valued for the production of varnishes , adhesives , and food glazing agents . They are also prized as raw materials for the synthesis of other organic compounds and provide constituents of incense and perfume . The oldest known use of plant resin comes from the late Middle Stone Age in Southern Africa where it

1520-479: The shikimate/chorizmate or succinylbenzoate pathway, which produces the phenyl propanoid derivatives (C6–C3); (ii) the acetate/malonate or polyketide pathway, which produces the side-chain-elongated phenyl propanoids, including the large group of flavonoids (C6–C3–C6) and some quinones; and (iii) the acetate/mevalonate pathway, which produces the aromatic terpenoids, mostly monoterpenes, by dehydrogenation reactions. The aromatic amino acid phenylalanine , synthesized in

1560-617: The tanning industry. Some natural phenols have been proposed as biopesticides . Furanoflavonoids like karanjin or rotenoids are used as acaricide or insecticide . Some phenols are sold as dietary supplements . Phenols have been investigated as drugs. For instance, Crofelemer (USAN trade name Fulyzaq) is a drug under development for the treatment of diarrhea associated with anti-HIV drugs. Additionally, derivatives have been made of phenolic compound, combretastatin A-4 , an anticancer molecule, including nitrogen or halogens atoms to increase

1600-459: Was used as an adhesive for hafting stone tools. The hard transparent resins, such as the copals, dammars , mastic , and sandarac , are principally used for varnishes and adhesives, while the softer odoriferous oleo-resins ( frankincense , elemi , turpentine , copaiba ), and gum resins containing essential oils ( ammoniacum , asafoetida , gamboge , myrrh , and scammony ) are more used for therapeutic purposes, food and incense . The resin of

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