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Phytoalexin

April 11, 2024

Phytoalexins are antimicrobial substances, some of which are antioxidative as well. They are defined, not by their having any particular chemical structure or character, but by the fact that they are defensively synthesized de novo by plants that produce the compounds rapidly at sites of pathogen infection. In general phytoalexins are broad spectrum inhibitors; they are chemically diverse, and different chemical classes of compounds are characteristic of particular plant taxa. Phytoalexins tend to fall into several chemical classes, including terpenoids, glycosteroids, and alkaloids; however the term applies to any phytochemicals that are induced by microbial infection.

Capsidiol is a phytoalexin produced by certain plants in response to pathogenic attack

Function edit

Phytoalexins are produced in plants to act as toxins to the attacking organism. They may puncture the cell wall, delay maturation, disrupt metabolism or prevent reproduction of the pathogen in question. Their importance in plant defense is indicated by an increase in susceptibility of plant tissue to infection when phytoalexin biosynthesis is inhibited. Mutants incapable of phytoalexin production exhibit more extensive pathogen colonization as compared to wild types. As such, host-specific pathogens capable of degrading phytoalexins are more virulent than those unable to do so.[1]

When a plant cell recognizes particles from damaged cells or particles from the pathogen, the plant launches a two-pronged resistance: a general short-term response and a delayed long-term specific response.[citation needed]

As part of the induced resistance, the short-term response, the plant deploys reactive oxygen species such as superoxide and hydrogen peroxide to kill invading cells. In pathogen interactions, the common short-term response is the hypersensitive response, in which cells surrounding the site of infection are signaled to undergo apoptosis, or programmed cell death, in order to prevent the spread of the pathogen to the rest of the plant.[citation needed]

Long-term resistance, or systemic acquired resistance (SAR), involves communication of the damaged tissue with the rest of the plant using plant hormones such as jasmonic acid, ethylene, abscisic acid, or salicylic acid. The reception of the signal leads to global changes within the plant, which induce expression of genes that protect from further pathogen intrusion, including enzymes involved in the production of phytoalexins. Often, if jasmonates or ethylene (both gaseous hormones) are released from the wounded tissue, neighboring plants also manufacture phytoalexins in response. For herbivores, common vectors for plant diseases, these and other wound response aromatics seem to act as a warning that the plant is no longer edible.[citation needed] Also, in accordance with the old adage, "an enemy of my enemy is my friend", the aromatics may alert natural enemies of the plant invaders to the presence thereof.

Recent research edit

Allixin (3-hydroxy-5-methoxy-6-methyl-2-pentyl-4H-pyran-4-one), a non-sulfur-containing compound having a γ-pyrone skeletal structure, was the first compound isolated from garlic as a phytoalexin, a product induced in plants by continuous stress.[2] This compound has been shown to have unique biological properties, such as anti-oxidative effects,[2] anti-microbial effects,[2] anti-tumor promoting effects,[3] inhibition of aflatoxin B2 DNA binding,[4] and neurotrophic effects.[4] Allixin showed an anti-tumor promoting effect in vivo, inhibiting skin tumor formation by TPA in DMBA initiated mice.[3] Herein, allixin and/or its analogs may be expected to be useful compounds for cancer prevention or chemotherapy agents for other diseases.[citation needed]

Role of natural phenols in the plant defense against fungal pathogens edit

Polyphenols, especially isoflavonoids and related substances, play a role in the plant defense against fungal and other microbial pathogens.

In Vitis vinifera grape, trans-resveratrol is a phytoalexin produced against the growth of fungal pathogens such as Botrytis cinerea[5] and delta-viniferin is another grapevine phytoalexin produced following fungal infection by Plasmopara viticola.[6] Pinosylvin is a pre-infectious stilbenoid toxin (i.e. synthesized prior to infection), contrary to phytoalexins which are synthesized during infection. It is present in the heartwood of Pinaceae.[7] It is a fungitoxin protecting the wood from fungal infection.[8]

Sakuranetin is a flavanone, a type of flavonoid. It can be found in Polymnia fruticosa[9] and rice, where it acts as a phytoalexin against spore germination of Pyricularia oryzae.[10] In Sorghum, the SbF3'H2 gene, encoding a flavonoid 3'-hydroxylase, seems to be expressed in pathogen-specific 3-deoxyanthocyanidin phytoalexin synthesis,[11] for example in Sorghum-Colletotrichum interactions.[12]

6-Methoxymellein is a dihydroisocoumarin and a phytoalexin induced in carrot slices by UV-C,[13] that allows resistance to Botrytis cinerea[14] and other microorganisms.[15]

Danielone is a phytoalexin found in the papaya fruit. This compound showed high antifungal activity against Colletotrichum gloesporioides, a pathogenic fungus of papaya.[16]

Stilbenes are produced in Eucalyptus sideroxylon in case of pathogen attacks. Such compounds can be implied in the hypersensitive response of plants. High levels of polyphenols in some woods can explain their natural preservation against rot.[17]

Avenanthramides are phytoalexins produced by Avena sativa in its response to Puccinia coronata var. avenae f. sp. avenae, the oat crown rust.[18][19] (Avenanthramides were formerly called avenalumins.)[20]

See also edit

References edit

  1. ^ Glazebrook, J; Ausubel, F M (1994). "Isolation of phytoalexin-deficient mutants of Arabidopsis thaliana and characterization of their interactions with bacterial pathogens". PNAS. 91 (19): 8955–8959. Bibcode:1994PNAS...91.8955G. doi:10.1073/pnas.91.19.8955. PMC 44725. PMID 8090752.
  2. ^ a b c Kodera Y, Matuura H, Yoshida S, Sumida T, Itakura Y, Fuwa T, Nishino H (1989). "Allixin, a stress compound from garlic". Chem. Pharm. Bull. 37 (6): 1656–1658. doi:10.1248/cpb.37.1656.
  3. ^ a b Nishino H, Nishino A, Takayama J, Iwashima A, Itakura Y, Kodera Y, Matsuura H, Fuwa T (1990). "Antitumor promoting activity of allixin, a stress compound produced by garlic". Cancer J. 3: 20–21.
  4. ^ a b Yamasaki T.; Teel R. W.; Lau B. H. S. (1991). "Effect of allixin, a phytoalexin produced by garlic, on mutagenesis, DNA-binding and metabolism of aflatoxin B1". Cancer Lett. 59 (2): 89–94. doi:10.1016/0304-3835(91)90171-D. PMID 1909211.
  5. ^ F. Favaron; M. Lucchetta; S. Odorizzi; A.T. Pais da Cunha; L. Sella (2009). "The role of grape polyphenols on trans-resveratrol activity against Botrytis cinerea and of fungal laccase on the solubility of putative grape PR proteins" (PDF). Journal of Plant Pathology. 91 (3): 579–588. Retrieved 2011-01-22.
  6. ^ Timperio, Anna Maria; d’Alessandro, Angelo; Fagioni, Marco; Magro, Paolo; Zolla, Lello (2012). "Production of the phytoalexins trans-resveratrol and delta-viniferin in two economy-relevant grape cultivars upon infection with Botrytis cinerea in field conditions". Plant Physiology and Biochemistry. 50 (1): 65–71. doi:10.1016/j.plaphy.2011.07.008. PMID 21821423.
  7. ^ Hovelstad, Hanne; Leirset, Ingebjorg; Oyaas, Karin; Fiksdahl, Anne (2006). "Screening Analyses of Pinosylvin Stilbenes, Resin Acids and Lignans in Norwegian Conifers". Molecules. 11 (1): 103–14. doi:10.3390/11010103. PMC 6148674. PMID 17962750.
  8. ^ Lee, S.K.; Lee, H.J.; Min, H.Y.; Park, E.J.; Lee, K.M.; Ahn, Y.H.; Cho, Y.J.; Pyee, J.H. (2005). "Antibacterial and antifungal activity of pinosylvin, a constituent of pine". Fitoterapia. 76 (2): 258–60. doi:10.1016/j.fitote.2004.12.004. PMID 15752644.
  9. ^ . home.ncifcrf.gov. Archived from the original on 2018-12-03. Retrieved 2012-04-13.
  10. ^ Kodama, Osamu; Miyakawa, Junichi; Akatsuka, Tadami; Kiyosawa, Shigehisa (1992). "Sakuranetin, a flavanone phytoalexin from ultraviolet-irradiated rice leaves". Phytochemistry. 31 (11): 3807–3809. Bibcode:1992PChem..31.3807K. doi:10.1016/S0031-9422(00)97532-0.
  11. ^ Chun-Hat Shih; Ivan K. Chu; Wing Kin Yip; Clive Lo (2006). "Differential Expression of Two Flavonoid 3'-Hydroxylase cDNAs Involved in Biosynthesis of Anthocyanin Pigments and 3-Deoxyanthocyanidin Phytoalexins in Sorghum". Plant and Cell Physiology. 47 (10): 1412–1419. doi:10.1093/pcp/pcl003. PMID 16943219.
  12. ^ Chopra, Surinder; Gaffoor, Iffa; Ibraheem, Farag. . Archived from the original on 2011-07-25.
  13. ^ Mercier, J.; Arul, J.; Ponnampalam, R.; Boulet, M. (1993). "Induction of 6-Methoxymellein and Resistance to Storage Pathogens in Carrot Slices by UV-C". Journal of Phytopathology. 137: 44–54. doi:10.1111/j.1439-0434.1993.tb01324.x.
  14. ^ Hoffman, R.; Heale, J.B. (1987). "Cell death, 6-methoxymellein accumulation, and induced resistance to Botrytis cinerea in carrot root slices". Physiological and Molecular Plant Pathology. 30: 67–75. doi:10.1016/0885-5765(87)90083-X.
  15. ^ Kurosaki, Fumiya; Nishi, Arasuke (1983). "Isolation and antimicrobial activity of the phytoalexin 6-methoxymellein from cultured carrot cells". Phytochemistry. 22 (3): 669. Bibcode:1983PChem..22..669K. doi:10.1016/S0031-9422(00)86959-9.
  16. ^ Echeverri, Fernando; Torres, Fernando; Quiñones, Winston; Cardona, Gloria; Archbold, Rosendo; Roldan, Javier; Brito, Ivan; Luis, Javier G.; Lahlou, El-Hassane (1997). "Danielone, a phytoalexin from papaya fruit". Phytochemistry. 44 (2): 255–256. Bibcode:1997PChem..44..255E. doi:10.1016/S0031-9422(96)00418-9. PMID 9004541.
  17. ^ Hart, John H.; Hillis, W. E. (1974). "Inhibition of wood-rotting fungi by stilbenes and other polyphenols in Eucalyptus sideroxylon". Phytopathology. 64 (7): 939–48. doi:10.1094/Phyto-64-939.
  18. ^ Mayama, S.; Bordin, A.P.A.; Morikawa, T.; Tanpo, H.; Kato, H. (1995). "Association of avenalumin accumulation with co-segregation of victorin sensitivity and crown rust resistance in oat lines carrying the Pc-2 gene". Physiological and Molecular Plant Pathology. 46 (4): 263–274. doi:10.1006/pmpp.1995.1021. S2CID 82948086.
  19. ^ Mayama, S.; Matsuura, Y.; Iida, H.; Tani, T. (1982). "The role of avenalumin in the resistance of oat to crown rust, Puccinia coronata f. sp. avenae". Physiological Plant Pathology. 20 (2): 189–199. doi:10.1016/0048-4059(82)90084-4.
  20. ^ Hammerschmidt, Ray (1999). "Phytoalexins: What Have We Learned After 60 Years?". Annual Review of Phytopathology. 37 (1): 285–306. doi:10.1146/annurev.phyto.37.1.285. PMID 11701825.

Further reading edit

  • Moriguchi, Toru; Matsuura, Hiromichi; Itakura, Yoichi; Katsuki, Hiroshi; Saito, Hiroshi; Nishiyama, Nobuyoshi (1997). "Allixin, a phytoalexin produced by garlic, and its analogues as novel exogenous substances with neurotrophic activity". Life Sciences. 61 (14): 1413–1420. doi:10.1016/S0024-3205(97)00687-5. PMID 9335231.
  • Kodera, Yukihiro; Ichikawa, Makoto; Yoshida, Jiro; Kashimoto, Naoki; Uda, Naoto; Sumioka, Isao; Ide, Nagatoshi; Ono, Kazuhisa (2002). "Pharmacokinetic Study of Allixin, a Phytoalexin Produced by Garlic". Chemical and Pharmaceutical Bulletin. 50 (3): 354–363. doi:10.1248/cpb.50.354. PMID 11911198.

External links edit

  • Guy L. de Bruxelles and Michael R Roberts
  • Linda L. Walling
  • The Chemical Defenses of Higher Plants Gerald A. Rosenthal
  • Martin Heil
  • Notes from the Underground Donald R. Strong and Donald A. Phillips
  • Loretta L. Mannix

April 11, 2024
phytoalexin, antimicrobial, substances, some, which, antioxidative, well, they, defined, their, having, particular, chemical, structure, character, fact, that, they, defensively, synthesized, novo, plants, that, produce, compounds, rapidly, sites, pathogen, in. Phytoalexins are antimicrobial substances some of which are antioxidative as well They are defined not by their having any particular chemical structure or character but by the fact that they are defensively synthesized de novo by plants that produce the compounds rapidly at sites of pathogen infection In general phytoalexins are broad spectrum inhibitors they are chemically diverse and different chemical classes of compounds are characteristic of particular plant taxa Phytoalexins tend to fall into several chemical classes including terpenoids glycosteroids and alkaloids however the term applies to any phytochemicals that are induced by microbial infection Capsidiol is a phytoalexin produced by certain plants in response to pathogenic attack Contents 1 Function 2 Recent research 3 Role of natural phenols in the plant defense against fungal pathogens 4 See also 5 References 6 Further reading 7 External linksFunction editPhytoalexins are produced in plants to act as toxins to the attacking organism They may puncture the cell wall delay maturation disrupt metabolism or prevent reproduction of the pathogen in question Their importance in plant defense is indicated by an increase in susceptibility of plant tissue to infection when phytoalexin biosynthesis is inhibited Mutants incapable of phytoalexin production exhibit more extensive pathogen colonization as compared to wild types As such host specific pathogens capable of degrading phytoalexins are more virulent than those unable to do so 1 When a plant cell recognizes particles from damaged cells or particles from the pathogen the plant launches a two pronged resistance a general short term response and a delayed long term specific response citation needed As part of the induced resistance the short term response the plant deploys reactive oxygen species such as superoxide and hydrogen peroxide to kill invading cells In pathogen interactions the common short term response is the hypersensitive response in which cells surrounding the site of infection are signaled to undergo apoptosis or programmed cell death in order to prevent the spread of the pathogen to the rest of the plant citation needed Long term resistance or systemic acquired resistance SAR involves communication of the damaged tissue with the rest of the plant using plant hormones such as jasmonic acid ethylene abscisic acid or salicylic acid The reception of the signal leads to global changes within the plant which induce expression of genes that protect from further pathogen intrusion including enzymes involved in the production of phytoalexins Often if jasmonates or ethylene both gaseous hormones are released from the wounded tissue neighboring plants also manufacture phytoalexins in response For herbivores common vectors for plant diseases these and other wound response aromatics seem to act as a warning that the plant is no longer edible citation needed Also in accordance with the old adage an enemy of my enemy is my friend the aromatics may alert natural enemies of the plant invaders to the presence thereof Recent research editAllixin 3 hydroxy 5 methoxy 6 methyl 2 pentyl 4H pyran 4 one a non sulfur containing compound having a g pyrone skeletal structure was the first compound isolated from garlic as a phytoalexin a product induced in plants by continuous stress 2 This compound has been shown to have unique biological properties such as anti oxidative effects 2 anti microbial effects 2 anti tumor promoting effects 3 inhibition of aflatoxin B2 DNA binding 4 and neurotrophic effects 4 Allixin showed an anti tumor promoting effect in vivo inhibiting skin tumor formation by TPA in DMBA initiated mice 3 Herein allixin and or its analogs may be expected to be useful compounds for cancer prevention or chemotherapy agents for other diseases citation needed Role of natural phenols in the plant defense against fungal pathogens editPolyphenols especially isoflavonoids and related substances play a role in the plant defense against fungal and other microbial pathogens In Vitis vinifera grape trans resveratrol is a phytoalexin produced against the growth of fungal pathogens such as Botrytis cinerea 5 and delta viniferin is another grapevine phytoalexin produced following fungal infection by Plasmopara viticola 6 Pinosylvin is a pre infectious stilbenoid toxin i e synthesized prior to infection contrary to phytoalexins which are synthesized during infection It is present in the heartwood of Pinaceae 7 It is a fungitoxin protecting the wood from fungal infection 8 Sakuranetin is a flavanone a type of flavonoid It can be found in Polymnia fruticosa 9 and rice where it acts as a phytoalexin against spore germination of Pyricularia oryzae 10 In Sorghum the SbF3 H2 gene encoding a flavonoid 3 hydroxylase seems to be expressed in pathogen specific 3 deoxyanthocyanidin phytoalexin synthesis 11 for example in Sorghum Colletotrichum interactions 12 6 Methoxymellein is a dihydroisocoumarin and a phytoalexin induced in carrot slices by UV C 13 that allows resistance to Botrytis cinerea 14 and other microorganisms 15 Danielone is a phytoalexin found in the papaya fruit This compound showed high antifungal activity against Colletotrichum gloesporioides a pathogenic fungus of papaya 16 Stilbenes are produced in Eucalyptus sideroxylon in case of pathogen attacks Such compounds can be implied in the hypersensitive response of plants High levels of polyphenols in some woods can explain their natural preservation against rot 17 Avenanthramides are phytoalexins produced by Avena sativa in its response to Puccinia coronata var avenae f sp avenae the oat crown rust 18 19 Avenanthramides were formerly called avenalumins 20 See also editAlexin humoral immunity Allicin Garlic Plant defense against herbivory Pterostilbene SalvestrolReferences edit Glazebrook J Ausubel F M 1994 Isolation of phytoalexin deficient mutants of Arabidopsis thaliana and characterization of their interactions with bacterial pathogens PNAS 91 19 8955 8959 Bibcode 1994PNAS 91 8955G doi 10 1073 pnas 91 19 8955 PMC 44725 PMID 8090752 a b c Kodera Y Matuura H Yoshida S Sumida T Itakura Y Fuwa T Nishino H 1989 Allixin a stress compound from garlic Chem Pharm Bull 37 6 1656 1658 doi 10 1248 cpb 37 1656 a b Nishino H Nishino A Takayama J Iwashima A Itakura Y Kodera Y Matsuura H Fuwa T 1990 Antitumor promoting activity of allixin a stress compound produced by garlic Cancer J 3 20 21 a b Yamasaki T Teel R W Lau B H S 1991 Effect of allixin a phytoalexin produced by garlic on mutagenesis DNA binding and metabolism of aflatoxin B1 Cancer Lett 59 2 89 94 doi 10 1016 0304 3835 91 90171 D PMID 1909211 F Favaron M Lucchetta S Odorizzi A T Pais da Cunha L Sella 2009 The role of grape polyphenols on trans resveratrol activity against Botrytis cinerea and of fungal laccase on the solubility of putative grape PR proteins PDF Journal of Plant Pathology 91 3 579 588 Retrieved 2011 01 22 Timperio Anna Maria d Alessandro Angelo Fagioni Marco Magro Paolo Zolla Lello 2012 Production of the phytoalexins trans resveratrol and delta viniferin in two economy relevant grape cultivars upon infection with Botrytis cinerea in field conditions Plant Physiology and Biochemistry 50 1 65 71 doi 10 1016 j plaphy 2011 07 008 PMID 21821423 Hovelstad Hanne Leirset Ingebjorg Oyaas Karin Fiksdahl Anne 2006 Screening Analyses of Pinosylvin Stilbenes Resin Acids and Lignans in Norwegian Conifers Molecules 11 1 103 14 doi 10 3390 11010103 PMC 6148674 PMID 17962750 Lee S K Lee H J Min H Y Park E J Lee K M Ahn Y H Cho Y J Pyee J H 2005 Antibacterial and antifungal activity of pinosylvin a constituent of pine Fitoterapia 76 2 258 60 doi 10 1016 j fitote 2004 12 004 PMID 15752644 Structure and Data for Sakuranetin NSC 407228 home ncifcrf gov Archived from the original on 2018 12 03 Retrieved 2012 04 13 Kodama Osamu Miyakawa Junichi Akatsuka Tadami Kiyosawa Shigehisa 1992 Sakuranetin a flavanone phytoalexin from ultraviolet irradiated rice leaves Phytochemistry 31 11 3807 3809 Bibcode 1992PChem 31 3807K doi 10 1016 S0031 9422 00 97532 0 Chun Hat Shih Ivan K Chu Wing Kin Yip Clive Lo 2006 Differential Expression of Two Flavonoid 3 Hydroxylase cDNAs Involved in Biosynthesis of Anthocyanin Pigments and 3 Deoxyanthocyanidin Phytoalexins in Sorghum Plant and Cell Physiology 47 10 1412 1419 doi 10 1093 pcp pcl003 PMID 16943219 Chopra Surinder Gaffoor Iffa Ibraheem Farag Biosynthesis and regulation of 3 deoxyanthocyanidin phytoalexins induced during Sorghum Colletotrichum interaction Heterologous expression in maize Archived from the original on 2011 07 25 Mercier J Arul J Ponnampalam R Boulet M 1993 Induction of 6 Methoxymellein and Resistance to Storage Pathogens in Carrot Slices by UV C Journal of Phytopathology 137 44 54 doi 10 1111 j 1439 0434 1993 tb01324 x Hoffman R Heale J B 1987 Cell death 6 methoxymellein accumulation and induced resistance to Botrytis cinerea in carrot root slices Physiological and Molecular Plant Pathology 30 67 75 doi 10 1016 0885 5765 87 90083 X Kurosaki Fumiya Nishi Arasuke 1983 Isolation and antimicrobial activity of the phytoalexin 6 methoxymellein from cultured carrot cells Phytochemistry 22 3 669 Bibcode 1983PChem 22 669K doi 10 1016 S0031 9422 00 86959 9 Echeverri Fernando Torres Fernando Quinones Winston Cardona Gloria Archbold Rosendo Roldan Javier Brito Ivan Luis Javier G Lahlou El Hassane 1997 Danielone a phytoalexin from papaya fruit Phytochemistry 44 2 255 256 Bibcode 1997PChem 44 255E doi 10 1016 S0031 9422 96 00418 9 PMID 9004541 Hart John H Hillis W E 1974 Inhibition of wood rotting fungi by stilbenes and other polyphenols in Eucalyptus sideroxylon Phytopathology 64 7 939 48 doi 10 1094 Phyto 64 939 Mayama S Bordin A P A Morikawa T Tanpo H Kato H 1995 Association of avenalumin accumulation with co segregation of victorin sensitivity and crown rust resistance in oat lines carrying the Pc 2 gene Physiological and Molecular Plant Pathology 46 4 263 274 doi 10 1006 pmpp 1995 1021 S2CID 82948086 Mayama S Matsuura Y Iida H Tani T 1982 The role of avenalumin in the resistance of oat to crown rust Puccinia coronata f sp avenae Physiological Plant Pathology 20 2 189 199 doi 10 1016 0048 4059 82 90084 4 Hammerschmidt Ray 1999 Phytoalexins What Have We Learned After 60 Years Annual Review of Phytopathology 37 1 285 306 doi 10 1146 annurev phyto 37 1 285 PMID 11701825 Further reading editMoriguchi Toru Matsuura Hiromichi Itakura Yoichi Katsuki Hiroshi Saito Hiroshi Nishiyama Nobuyoshi 1997 Allixin a phytoalexin produced by garlic and its analogues as novel exogenous substances with neurotrophic activity Life Sciences 61 14 1413 1420 doi 10 1016 S0024 3205 97 00687 5 PMID 9335231 Kodera Yukihiro Ichikawa Makoto Yoshida Jiro Kashimoto Naoki Uda Naoto Sumioka Isao Ide Nagatoshi Ono Kazuhisa 2002 Pharmacokinetic Study of Allixin a Phytoalexin Produced by Garlic Chemical and Pharmaceutical Bulletin 50 3 354 363 doi 10 1248 cpb 50 354 PMID 11911198 External links editSignals Regulating Multiple Responses to Wounding and Herbivores Guy L de Bruxelles and Michael R Roberts The Myriad Plant Responses to Herbivores Linda L Walling The Chemical Defenses of Higher Plants Gerald A Rosenthal Induced Systemic Resistance ISR Against Pathogens in the Context of Induced Plant Defences Martin Heil Notes from the Underground Donald R Strong and Donald A Phillips Relationships Among Plants Insect Herbivores Pathogens and Parasitoids Expressed by Secondary Metabolites Loretta L Mannix Retrieved from https en wikipedia org w index php title Phytoalexin amp oldid 1184131555, wikipedia, wiki, book, books, library,

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