Abamectin

Abamectin
Clinical data
Other names	Avermectin B1 (CAS name), MK-936
ATCvet code	QP54AA02 (WHO) ;
Legal status
Legal status	AU: S5 (Caution) / S6;
Identifiers
	IUPAC name Mixture of:; (10E,14E,16E)-(1R,4S,5′S,6S,6′R,8R,12S,13S,20R,21R,24S)-6′-[(S)-sec-butyl]-21,24-dihydroxy-5′,11,13,22-tetramethyl-2-oxo-(3,7,19-trioxatetracyclo[15.6.1.14,8.020,24]pentacosa-10,14,16,22-tetraene)-6-spiro-2′-(5′,6′-dihydro-2′H-pyran)-12-yl 2,6-dideoxy-4-O-(2,6-dideoxy-3-O-methyl-α-L-arabino-hexopyranosyl)-3-O-methyl-α-L-arabino-hexopyranoside; and; (10E,14E,16E)-(1R,4S,5′S,6S,6′R,8R,12S,13S,20R,21R,24S)-21,22-dihydroxy-6′-isopropyl-5′,11,13,22-tetramethyl-2-oxo-(3,7,19-trioxatetracyclo[15.6.1.14,8.020,24]pentacosa-10,14,16,22-tetraene)-6-spiro-2′-(5′,6′-dihydro-2′H-pyran)-12-yl 2,6-dideoxy-4-O-(2,6-dideoxy-3-O-methyl-α-L-arabino-hexopyranosyl)-3-O-methyl-α-L-arabino-hexopyranoside;
CAS Number	71751-41-2 ;
ChemSpider	8095964 ;
UNII	5U8924T11H;
KEGG	D02777 ;
ChEMBL	ChEMBL1630577 ;
CompTox Dashboard (EPA)	DTXSID8023892 ;
ECHA InfoCard	100.113.437
Chemical and physical data
Formula	C48H72O14 (B1a); C47H70O14 (B1b)
3D model (JSmol)	;
	SMILES CC[C@H](C)[C@H]1O[C@@]2(C[C@@H]3C[C@@H](C\C=C(/C)\[C@@H](O[C@H]4C[C@H](OC)[C@@H](O[C@H]5C[C@H](OC)[C@@H](O)[C@H](C)O5)[C@H](C)O4)[C@@H](C)\C=C\C=C\6/CO[C@@H]7[C@H](O)C(=C[C@@H](C(=O)O3)[C@]67O)C)O2)C=C[C@@H]1C;
	InChI InChI=1S/C48H72O14.C47H70O14/c1-11-25(2)43-28(5)17-18-47(62-43)23-34-20-33(61-47)16-15-27(4)42(26(3)13-12-14-32-24-55-45-40(49)29(6)19-35(46(51)58-34)48(32,45)52)59-39-22-37(54-10)44(31(8)57-39)60-38-21-36(53-9)41(50)30(7)56-38;1-24(2)41-27(5)16-17-46(61-41)22-33-19-32(60-46)15-14-26(4)42(25(3)12-11-13-31-23-54-44-39(48)28(6)18-34(45(50)57-33)47(31,44)51)58-38-21-36(53-10)43(30(8)56-38)59-37-20-35(52-9)40(49)29(7)55-37/h12-15,17-19,25-26,28,30-31,33-45,49-50,52H,11,16,20-24H2,1-10H3;11-14,16-18,24-25,27,29-30,32-44,48-49,51H,15,19-23H2,1-10H3/b13-12+,27-15+,32-14+;12-11+,26-14+,31-13+/t25-,26-,28-,30-,31-,33+,34-,35-,36-,37-,38-,39-,40+,41-,42-,43+,44-,45+,47+,48+;25-,27-,29-,30-,32+,33-,34-,35-,36-,37-,38-,39+,40-,41+,42-,43-,44+,46+,47+/m00/s1 ; Key:IBSREHMXUMOFBB-JFUDTMANSA-N ;
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Abamectin (also called avermectin B₁) is a widely used insecticide and anthelmintic. Abamectin, is a member of the avermectin family and is a natural fermentation product of soil dwelling^[1] actinomycete Streptomyces avermitilis.^[2] Abamectin differs from ivermectin, the popular member of the avermectin family, by a double bond between carbons 22 and 25.^[2] Fermentation of Streptomyces avermitilis yields eight closely related avermectin homologs, with the B_1a and B_1b forms comprising the majority of the fermentation.^[3] The non-proprietary name, abamectin, refers to a mixture of B_1a (~80%) and B_1b (~20%).^[3] Out of all the avermectins, abamectin is the only one that is used both in agriculture and pharmaceuticals.^[4]

Mode of Action

Avermectins bind to the glutamate-gated chloride channels that are found in invertebrate nerve and muscle cells.^[5] They cause hyperpolarization of these cells resulting in paralysis and death.^[5] Mammals only possess glutamate-gated chloride channels in the brain and spinal cord and as the avermectins have a low affinity for other mammalian ligand-gated channels and do not usually cross the blood–brain barrier, they are very safe for mammals.^[6]

History

Avermectins were discovered in 1967 in fermentation broths of an actinomycete culture received from the Kitasato Institute in Japan, following an intensive search designed to find natural products with anthelmintic activity.^[7] It was not until 1985 ivermectin was first used to treat infections with Onchocerca volvulus (onchocerciasis or river blindness) in humans by the United Nations.^[8] The discoverers of avermectin, William C. Campbell and Satoshi Ōmura, shared the 2015 Nobel Prize in Physiology or Medicine.^[9]

Activity

Abamectin is an insecticide as well as an acaricide (miticide)^[2] and a nematicide. It is also used to control fire ants.^[10] Abamectin is provided orally to horses for deworming them.^[11]

Use

Abamectin is also used as a veterinary antihelmintic. Resistance to abamectin-based antihelmintics, although a growing problem, is not as common as to other classes of veterinary antihelmintics.^{[citation needed]} The benzoate salt emamectin benzoate is also used as an insecticide. Avermectins have been used to treat various ailments caused by parasites in both humans and animals.^[12] Avermectins including abamectin were studied for use as anti alcohol therapies.^[13]^[12] Recently, ivermectin is being studied for use as an anti inflammatory agent.^[14]

Environmental Fate

Abamectin degrades rapidly when exposed to light (photodegradation) on plant surfaces, in soil, dung and water.^[15] Half life of Avermectins (including abamectin) varies between 0.5 and 23 days depending on the rate and substrate (water, soil, faeces or plant).^[16] Avermectin B_1a applied at 0.02-0.03 lb ai/acre (50% higher than recommended rates) resulted in very low residue.^[17]

Non targets

Abamectin is highly toxic to bees either if they consume or come in direct contact.^[18] However, plant parts exposed to abamectin spraying did not cause toxicity to bees 24 hours after treatment.^[18]^[19] The reason for lower toxicity in foliage is due to a half life <24 hours in plant surfaces.^[16]

Trade names

Trade names include Abba, Abathor, Affirm, Agri-Mek, Avid, Dynamec, Epi-Mek, Genesis Horse Wormer, Reaper, Termictine 5%, Vertimec, CAM-MEK 1.8% EC (cam for agrochemicals), Zephyr and Cure 1.8 EC.^{[citation needed]}

References

^ Ikeda H, Ishikawa J, Hanamoto A, Shinose M, Kikuchi H, Shiba T, et al. (May 2003). "Complete genome sequence and comparative analysis of the industrial microorganism Streptomyces avermitilis". Nature Biotechnology. 21 (5): 526–531. doi:10.1038/nbt820. PMID 12692562.
^ ^a ^b ^c Campbell WC (6 December 2012). Ivermectin and Abamectin. Springer Science & Business Media. pp. 304–. ISBN 978-1-4612-3626-9.
^ ^a ^b Jansson RK, Dybas RA (1998). "Avermectins: Biochemical Mode of Action, Biological Activity and Agricultural Importance". In Ishaaya I, Degheele D (eds.). Insecticides with Novel Modes of Action: Mechanisms and Application. Applied Agriculture. Berlin, Heidelberg: Springer. pp. 152–170. doi:10.1007/978-3-662-03565-8_9. ISBN 978-3-662-03565-8.
^ Shoop WL, Mrozik H, Fisher MH (September 1995). "Structure and activity of avermectins and milbemycins in animal health". Veterinary Parasitology. 59 (2): 139–156. doi:10.1016/0304-4017(94)00743-V. PMID 7483237.
^ ^a ^b Wolstenholme AJ, Rogers AT (2006-03-29). "Glutamate-gated chloride channels and the mode of action of the avermectin/milbemycin anthelmintics". Parasitology. 131 Suppl (S1): S85–S95. doi:10.1017/S0031182005008218. PMID 16569295. S2CID 14474894.
^ Omura S, Crump A (September 2014). "Ivermectin: panacea for resource-poor communities?". Trends in Parasitology. 30 (9): 445–455. doi:10.1016/j.pt.2014.07.005. PMID 25130507.
^ Lasota JA, Dybas RA (1991). "Avermectins, a novel class of compounds: implications for use in arthropod pest control". Annual Review of Entomology. 36 (1): 91–117. doi:10.1146/annurev.en.36.010191.000515. PMID 2006872.
^ Crump A, Ōmura S (2011). "Ivermectin, 'wonder drug' from Japan: the human use perspective". Proceedings of the Japan Academy. Series B, Physical and Biological Sciences. 87 (2): 13–28. Bibcode:2011PJAB...87...13C. doi:10.2183/pjab.87.13. PMC 3043740. PMID 21321478.
^ "The Nobel Prize in Physiology or Medicine 2015". NobelPrize.org. Archived from the original on 2021-02-09. Retrieved 2021-04-09.
^ "Ascend / Advance | Texas Imported Fire Ant Research and Management Project". fireant.tamu.edu. Archived from the original on 2021-01-27. Retrieved 2021-04-08.
^ "Equine Megastore - Horse Wormers". www.equine-mega-store.com. Retrieved 2021-04-08.
^ ^a ^b El-Saber Batiha G, Alqahtani A, Ilesanmi OB, Saati AA, El-Mleeh A, Hetta HF, Magdy Beshbishy A (August 2020). "Avermectin Derivatives, Pharmacokinetics, Therapeutic and Toxic Dosages, Mechanism of Action, and Their Biological Effects". Pharmaceuticals. 13 (8): 196. doi:10.3390/ph13080196. PMC 7464486. PMID 32824399.
^ Yardley MM, Neely M, Huynh N, Asatryan L, Louie SG, Alkana RL, Davies DL (September 2014). "Multiday administration of ivermectin is effective in reducing alcohol intake in mice at doses shown to be safe in humans". NeuroReport. 25 (13): 1018–1023. doi:10.1097/wnr.0000000000000211. PMC 4126080. PMID 25004078.
^ Ventre E, Rozières A, Lenief V, Albert F, Rossio P, Laoubi L, et al. (August 2017). "Topical ivermectin improves allergic skin inflammation". Allergy. 72 (8): 1212–1221. doi:10.1111/all.13118. PMID 28052336. S2CID 4640628.
^ Halley BA, VandenHeuvel WJ, Wislocki PG (June 1993). "Environmental effects of the usage of avermectins in livestock". Veterinary Parasitology. 48 (1–4): 109–125. doi:10.1016/0304-4017(93)90149-H. PMID 8346626.
^ ^a ^b Bai SH, Ogbourne S (July 2016). "Eco-toxicological effects of the avermectin family with a focus on abamectin and ivermectin". Chemosphere. 154: 204–214. Bibcode:2016Chmsp.154..204B. doi:10.1016/j.chemosphere.2016.03.113. PMID 27058912.
^ Moye HA, Malagodi MH, Yoh J, Leibee GL, Ku CC, Wislocki PG (1987). "Residues of avermectin B1a in rotational crops and soils following soil treatment with [14C]avermectin B1a". Journal of Agricultural and Food Chemistry. 35 (6): 859–864. doi:10.1021/jf00078a003. ISSN 0021-8561.
^ ^a ^b Wislocki PG, Grosso LS, Dybas RA (1989). "Environmental Aspects of Abamectin Use in Crop Protection". Ivermectin and Abamectin. New York, NY: Springer New York. pp. 182–200. doi:10.1007/978-1-4612-3626-9_13. ISBN 978-1-4612-8184-9.
^ Lumaret JP, Errouissi F, Floate K, Römbke J, Wardhaugh K (May 2012). "A review on the toxicity and non-target effects of macrocyclic lactones in terrestrial and aquatic environments". Current Pharmaceutical Biotechnology. 13 (6): 1004–1060. doi:10.2174/138920112800399257. PMC 3409360. PMID 22039795.