Avilamycin A

Avilamycin A	Last updated: 15/09/2025
(Also known as: flambamycin)

GENERAL INFORMATION

Description

An oligosaccharide antibiotic drug active against gram-posive bacteria.

Examples of veterinary uses

Mainly used for pig and poultry growth promotion and to control bacterial enteric infections such as stress-induced post-weaning diarrhea in piglets, caused by Escherichia coli

Examples of species treated

Pigs; Poultry; Rabbits

Approval status

VMR 2013/2033 approval status (GB/UK)

Not approved

EU Regulatory approval status

Not approved

Chemical structure

Isomerism

Avilamycin A exhibits complex isomerism due to its intricate structure, which includes multiple chiral centres and glycosidic linkages. The molecule primarily shows stereoisomerism, with numerous asymmetric carbon atoms giving rise to optical isomers that influence its antibiotic activity. It also displays conformational isomerism, as its flexible sugar rings and linkages allow for different spatial arrangements that affect how it interacts with bacterial ribosomes. While geometric isomerism is less prominent, some side chains may exhibit restricted rotation.

Chemical formula

C₆₁H₈₈Cl₂O₃₂

Canonical SMILES

CC1C(C(CC(O1)OC2C(OC3(CC2O)OC4C(OC(CC4(O3)C)OC5C(C(OC(C5OC)C)OC6C(OC(C(C6O)OC)OC7C(C8C(CO7)OC9(O8)C1C(C(C(O9)C)(C(=O)C)O)OCO1)OC(=O)C(C)C)COC)O)C)C)O)OC(=O)C1=C(C(=C(C(=C1OC)Cl)O)Cl)C

Isomeric SMILES

C[C@@H]1[C@H]([C@@H](C[C@@H](O1)O[C@@H]2[C@H](OC3(C[C@H]2O)O[C@@H]4[C@H](O[C@H](C[C@]4(O3)C)O[C@@H]5[C@H]([C@@H](O[C@@H]([C@@H]5OC)C)O[C@@H]6[C@H](O[C@H]([C@H]([C@H]6O)OC)O[C@H]7[C@@H]([C@H]8[C@H](CO7)O[C@@]9(O8)[C@H]1[C@H]([C@@]([C@H](O9)C)(C(=O)C)O)OCO1)OC(=O)C(C)C)COC)O)C)C)O)OC(=O)C1=C(C(=C(C(=C1OC)Cl)O)Cl)C

International Chemical Identifier key (InChIKey)

XIRGHRXBGGPPKY-FCNCREMHSA-N

International Chemical Identifier (InChI)

InChI=1S/C61H88Cl2O32/c1-21(2)53(70)87-49-45-32(92-61(93-45)52-51(78-20-79-52)60(72,27(8)64)28(9)91-61)19-77-56(49)89-57-48(76-14)39(68)44(31(83-57)18-73-11)88-55-40(69)47(43(74-12)24(5)82-55)85-34-17-58(10)50(26(7)81-34)94-59(95-58)16-30(66)42(25(6)90-59)84-33-15-29(65)41(23(4)80-33)86-54(71)35-22(3)36(62)38(67)37(63)46(35)75-13/h21,23-26,28-34,39-45,47-52,55-57,65-69,72H,15-20H2,1-14H3/t23-,24-,25-,26-,28-,29-,30-,31-,32+,33+,34+,39+,40-,41-,42-,43+,44-,45-,47-,48+,49-,50-,51-,52-,55+,56+,57+,58-,59?,60+,61-/m1/s1

2D structure diagram/image available?

Yes

General status

Veterinary substance type

Antibiotic, Antibacterial, Medicinal drug, Growth promotor, Feed additive

Substance groups

Oligosaccharide

Minimum active substance purity

Known relevant impurities

Substance origin

Semi-synthetic

Mode of action

Inhibits the protein synthesis of susceptible micro-organisms, binds to the 50S ribosomal subunit

Molecular targets

[50S rRNA, Antagonist]

CAS RN

69787-79-7

Alternative/old CAS RN

11051-71-1 (avilamycin isomer mix)

EC number

CIPAC number

US EPA chemical code

PubChem CID

20054845

Therapeutic Class

Alimentary tract and metabolism: Antibiotics

ATCvet Code

QA07AA95

Controlled Drug?

Regulation 37/2010 MRL Classification

Molecular mass

1404.2

PIN (Preferred Identification Name)

IUPAC name

[(2R,3S,4R,6S)-6-[(2'R,3'S,3aR,4R,4'R,6S,7aR)-6-[(2S,3R,4R,5S,6R)-2-[(2R,3S,4S,5S,6S)-6-[(2R,3aS,3'aR,6S,6'R,7R,7'S,7aR,7'aR)-7'-acetyl-7'-hydroxy-6'-methyl-7-(2-methylpropanoyloxy)spiro[4,6,7,7a-tetrahydro-3aH-[1,3]dioxolo[4,5-c]pyran-2,4'-6,7a-dihydro-3aH-[1,3]dioxolo[4,5-c]pyran]-6-yl]oxy-4-hydroxy-5-methoxy-2-(methoxymethyl)oxan-3-yl]oxy-3-hydroxy-5-methoxy-6-methyloxan-4-yl]oxy-4'-hydroxy-2',4,7a-trimethylspiro[3a,4,6,7-tetrahydro-[1,3]dioxolo[4,5-c]pyran-2,6'-oxane]-3'-yl]oxy-4-hydroxy-2-methyloxan-3-yl] 3,5-dichloro-4-hydroxy-2-methoxy-6-methylbenzoate

CAS name

Forever chemical

Other status information

Relevant Environmental Water Quality Standards

Physical state

White crystalline solid with musky odour

Commercial

Property

Value

Availability status

Current

Introduction & key dates

1987, global introduction

Example manufacturers & suppliers of products using this active now or historically

Kavault

Example products using this active

Elanco Animal Health

Formulation and application details

Usually supplied as a medicated pre-mix feed

Commercial production

Avilamycin A is produced through a fermentation-based process using Streptomyces viridochromogenes, a soil-dwelling actinomycete. The production begins with culturing spores on a nutrient-rich medium to generate a seed culture, which is then inoculated into a fermentation broth. During fermentation, the bacteria synthesise avilamycin A as a secondary metabolite, with production regulated by specific genes like aviC1 and aviC2 that activate the biosynthetic gene cluster. Optimisation strategies, such as mutagenesis, medium composition adjustments, and supplementation with precursors like L-valine and D-xylose, can significantly enhance yield. After fermentation, the broth is processed to isolate and purify avilamycin A, typically through crystallisation and solvent extraction techniques.

Impact on climate of production and use

As microbial-based products tend to use fermentation-based production processes rather than chemical synthesis, they typically have a lower fossil fuel input in formulation and active ingredient creation, and also have reduced downstream emissions due to biodegradability and minimal soil disruption, their life-cycle GHG emissions are expected to be low. Whilst hard and precise data is not available, broad estimates suggest that typically emissions are likely to be below 5 kg CO₂e/kg.

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

Solubility - In water at 20 °C (mg l⁻¹)

41.0

Moderate

Solubility - In organic solvents at 20 °C (mg l⁻¹)

4000

Ethanol

5000

Methanol

10000

Ethyl acetate

50000

Acetone

Melting point (°C)

181

Boiling point (°C)

Degradation point (°C)

Flashpoint (°C)

Octanol-water partition coefficient at pH 7, 20 °C

3.55 X 10⁰²

Calculated

Log P

2.55

Low

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

Vapour pressure at 20 °C (mPa)

Henry's law constant at 25 °C (Pa m³ mol⁻¹)

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

Maximum UV-vis absorption L mol⁻¹ cm⁻¹

Surface tension (mN m⁻¹)

Refractive Index

Environmental release

Substance may enter the environment via the faeces of treated animals or by leaching from spilt medicated feed.

Degradation

Property

Value

Source; quality score; and other information

Interpretation

Soil degradation (days) (aerobic)

DT₅₀ (typical)

Non-persistent

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

Note

Literature states DT₅₀ in soil 3 to 4 weeks

Manure DT₅₀ (days)

Manure

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Note

Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7

Value

Note

Water-sediment DT₅₀ (days)

Water phase only DT₅₀ (days)

Sediment phase only DT₅₀ (days)

Air degradation

As this parameter is not normally measured directly, a surrogate measure is used: ‘Photochemical oxidative DT₅₀’. Where data is available, this can be found in the Fate Indices section below.

Decay in stored produce DT₅₀

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d (mL g⁻¹)

Slightly mobile

K_oc (mL g⁻¹)

2934

Notes and range

US data K_d range 23-109 mL g⁻¹, K_oc range 1769-3633 mL g⁻¹, Soils = 3 Literature K_oc values range 1802-3685 mL g⁻¹

Freundlich

K_f (mL g⁻¹)

K_foc (mL g⁻¹)

¹/_n

Notes and range

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

0.74

Calculated

Low leachability

Bio-concentration factor

BCF (l kg⁻¹)

CT₅₀ (days)

Known soil and groundwater metabolites

None

Other known metabolites

Metabolite name and reference

Aliases

Formation medium / Rate

Estimated maximum occurrence fraction

flambic acid

Rat (Liver); Livestock

flambalactone

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 4640

Rat

Low

Mammals - Short term dietary NOEL

(mg kg⁻¹)

(ppm diet)

Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)

Birds - Acute LD₅₀ (mg kg⁻¹)

> 372.5

Colinus virginianus

Moderate

Birds - Short term dietary (LC₅₀/LD₅₀)

> 745 ppm

Colinus virginianus

Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)

Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)

> 100

Lumbricus terrestris

Moderate

Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)

> 330

Lumbricus terrestris

Low

Soil micro-organisms

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Non-target plants

Vegetative vigour ER₅₀ (g ha⁻¹)

Seedling emergence ER₅₀ (g ha⁻¹)

Honeybees (Apis spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Unknown mode acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Chronic

Notes

Bumblebees (Bombus spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Mason bees (Osmia spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Other bee species (1)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Other bee species (2)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Beneficial insects (Ladybirds)

Beneficial insects (Lacewings)

Beneficial insects (Parasitic wasps)

Beneficial insects (Predatory mites)

Beneficial insects (Ground beetles)

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Temperate Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)

47.8

Oncorhynchus mykiss

Low

Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

Temperate Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

Temperate Freshwater Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)

23.8

Daphnia magna

Low

Tropical Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

Aquatic crustaceans - Acute 96 hour LC₅₀ (mg l⁻¹)

Sediment dwelling organisms - Acute 96 hour LC₅₀ (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, static, water (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg⁻¹)

Aquatic Plants (free-floating, fonds growth, fresh) - 7 day (mg l⁻¹)

Aquatic plants (rooted, growth rate, fresh) - 14 day (mg l⁻¹)

Algae - Acute (growth rate, fresh; mg l⁻¹) (EC₅₀)

> 10

Synechococcus leopoliensis

Low

Algae - Chronic (growth rate, fresh; mg l⁻¹)

Mesocosm study data

NOEAEC mg l⁻¹

Marine bivalves

HUMAN HEALTH AND PROTECTION

General

Property

Value

Source; quality score; and other information

Interpretation

Threshold of Toxicological Concern (Cramer Class)

High (class III)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 4640

Rat

Low

Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)

2000

Rabbit

Mammals - Inhalation LC₅₀ (mg l⁻¹)

Other Mammal toxicity endpoints

ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)

ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)

AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)

AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

Occupational

Mammalian dose elimination route and rate

Extensively metabolised and rapidly excreted in the faeces and urine

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

Possible liver toxicant

Handling issues

Property

Value and interpretation

General

No information available

CLP classification 2013

WHO Classification

Not listed (Not listed)

UN Number

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

avilamycin A

French

avilamycine A

German

Danish

Italian

Spanish

avilamycina A

Greek

Polish

Swedish

Hungarian

Dutch

Norwegian

Record last updated:	15/09/2025
Contact:	aeru@herts.ac.uk
Please cite as:	Lewis, K.A., Tzilivakis, J., Warner, D. and Green, A. (2016) An international database for pesticide risk assessments and management. Human and Ecological Risk Assessment: An International Journal, 22(4), 1050-1064. DOI: 10.1080/10807039.2015.1133242