Benzyl butyrate

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to microorganisms, other

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

Experimental data of test chemicals

Justification for type of information:

Experimental data of test chemicals are from collection of data

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

WoE was prepared from two studies for the determination of toxicity of test chemical on the growth of microorganisms.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

yes

Remarks:

WoE 2: dimethyl sulfoxide (DMSO), WoE 3: ethyl alcohol or DMSO

Details on test solutions:

WoE 2:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Chemical name of vehicle (organic solvent, emulsifier or dispersant):dimethyl sulfoxide (DMSO).

Sampling method:
In culture dishes (35 × 10mm) Muller Hinton agar medium was used for the measurement of MIC. DMSO used as solvent in which various concentrations of test chemical were prepared. The bacteria which was tested were pre-propagated with sensitivity test broth of NISSUI using shaking culture. The final incubated medium were diluted by 0.75% physiological saline to the microbial concentration of 10E6 CFU/ml. In the Muller Hinton agar medium having test chemical, 0.1ml of diluted culture solution was inoculated. MIC was determined after 24 hours of exposure at 37°C.

WoE 3:
- Sampling method: Test chemical solutions were prepared in either ethyl alcohol or DMSO depending on test chemical solubility.

Test organisms (species):

other: WoE 2: Corynebacterium minutissimum (CM),Arthrobacter sp,Staphylococ cus aureus,Staphylococcus epidermidis var.and Escherichia coli WoE 3: Corynebacterium minutissimum, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermis, Arthrobacter sp.

Details on inoculum:

WoE 2: Corynebacterium minutissimum (CM),Arthrobacter sp. isolated from Lipo-66,Staphylococ cus aureus (IAM-1011, (SA)),Staphylococcus epidermidis var. (SE) and Escherichia coli (ATCC 11775, (EC)) from the Department of Dermatology, University of Pennsylvania.


WoE 3: Details on inoculum
- Laboratory culture: Staphylococcus aureus (IAM-1011, SA) was purchased from Institute of Applied Microbiology, Tokyo university. Escherichia coli (ATCC 11775, (EC)) was purchased from Institute of Medical Science, Tokyo university. Corynebacterium minutissimum (ATCC 23348, (CM)) and Staphylococcus epidermis var. (SE) were gifted from the Department of Dermatology, University of
Pennsyvania. Arthrobacter sp. was isolated from Lipo-66.

Test type:

static

Water media type:

freshwater

Total exposure duration:

24 h

Test temperature:

WoE 3: 37°C

Details on test conditions:

WoE 2:
TEST SYSTEM
Test vessel: Agar plates
No. of organisms per vessel: microbial concentration of 10e6 CFU/ml

WoE 3:
TEST SYSTEM
- Test vessel: Culture dish was used as a test vessel.
- Material, size, headspace, fill volume: Culture dish of 35 X 10 mm dimension was used.

TEST MEDIUM / WATER PARAMETERS: Muller Hinton agar was used as a test medium.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): Minimum inhibitory concentration (MIC) was determined as the concentration where no growth of the test organism was observed after 24 hrs.

Reference substance (positive control):

no

Key result

Duration:

24 h

Dose descriptor:

other: MIC

Effect conc.:

> 2 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Remarks on result:

other: WoE 2

Duration:

24 h

Dose descriptor:

other: MIC

Effect conc.:

> 2 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Remarks on result:

other: WoE 3

Validity criteria fulfilled:

not specified

Conclusions:

The study was conducted for the determination of effect of test chemical on the various species and strains of microorganism. After the exposure period of test chemical with microorganisms for 24 hours, growth rate inhibition were calculated and the MIC was determined to be > 2000 mg/l.

Executive summary:

Summarized result for the determination of effect of test chemical on the growth rate inhibition of different microorganisms are as mentioned below:

 

 

The Minimum Inhibition (MIC) effect of test chemical was observed on 5 different species of microorganisms i.e. Corynebacterium minutissimum (CM), Arthrobacter sp. isolated from Lipo-66, Staphylococcus aureus (IAM-1011, (SA)),Staphylococcus epidermidis var. (SE) and Escherichia coli (ATCC 11775, (EC)). Microorganisms exposed with test chemical for period of 24 hrs. In culture dishes (35 × 10mm) Muller Hinton agar medium was used for the measurement of MIC. DMSO used as solvent in which various concentrations of test chemical were prepared. The bacteria which was tested were pre-propagated with sensitivity test broth of NISSUI using shaking culture. The final incubated medium was diluted by 0.75% physiological saline to the microbial concentration of 10E6 CFU/ml. In the Muller Hinton agar medium having test chemical, 0.1ml of diluted culture solution was inoculated. MIC was determined after 24 hours of exposure at 37°C. After the exposure of test chemical with different microorganism, MIC was counted. The Minimum Inhibitory Concentration of test chemical on various microorganisms Corynebacterium minutissimum (CM), Arthrobacter sp. isolated from Lipo-66,Staphylococcus aureus (IAM-1011, (SA)), Staphylococcus epidermidis var. (SE) and Escherichia coli (ATCC 11775, (EC) was determine to be >2000 mg/l (inoculum 10E6 CFU/plate) after 24 hours exposure with test chemical.

 

 

Above study further supported by the third weight of evidence report from peer reviewed journal. Toxicity to micro-organisms study was conducted using five different microorganisms. The study was performed for 24 hrs at 37°C.Test organism Staphylococcus aureus (IAM-1011, SA) was purchased from Institute of Applied Microbiology, Tokyo university. Escherichia coli(ATCC 11775, (EC)) was purchased from Institute of Medical Science, Tokyo university. Corynebacterium minutissimum (ATCC 23348, (CM)) and Staphylococcus epidermis var. (SE) were gifted from the Department of Dermatology, University of Pennsyvania. Arthrobacter sp. was isolated from Lipo-66. Culture dish of 35 X 10 mm dimension was used as a test vessel. Test chemical solutions were prepared in either ethyl alcohol or DMSO. Muller Hinton agar was used as a test medium. Test bacteria were pre-propagated with sensitivity test broth of NISSUI using shaking culture. Incubated mediums were diluted using 0.75% physiological saline to the microbial concentration of 10e6 CFU/ml. Test medium containing the test chemical was inoculated using 0.1 ml of diluted culture solution. MIC was determined after 24 hrs at 37°C. Based on the effect of test chemical on the growth inhibition of five different organisms such as Corynebacterium minutissimum, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermis, Arthrobacter spp. after the exposure period of 24 hours, the MIC value was determined to be > 2000 mg/l.

 

Thus, on the basis of above all studies on different microorganisms, the MIC was determined to be > 2000 mg/l.

Description of key information

The study was conducted for the determination of effect of test chemical on the various species and strains of microorganism. After the exposure period of test chemical with microorganisms for 24 hours, growth rate inhibition were calculated and the MIC was determined to be > 2000 mg/l.

Key value for chemical safety assessment

EC50 for microorganisms:

2 000 mg/L

Additional information

Summarized result for the determination of effect of test chemical andread-across analogues which is extracted by using mechanistic approach and functionally and structurally like the target chemicalon the growth rate inhibition of different microorganisms are as mentioned below:

 

The Minimum Inhibition (MIC) effect of test chemical was observed on 5 different species of microorganisms i.e. Corynebacterium minutissimum (CM), Arthrobacter sp. isolated from Lipo-66, Staphylococcus aureus (IAM-1011, (SA)),Staphylococcus epidermidis var. (SE) and Escherichia coli (ATCC 11775, (EC)). Microorganisms exposed with test chemical for period of 24 hrs. In culture dishes (35 × 10mm) Muller Hinton agar medium was used for the measurement of MIC. DMSO used as solvent in which various concentrations of test chemical were prepared. The bacteria which was tested were pre-propagated with sensitivity test broth of NISSUI using shaking culture. The final incubated medium was diluted by 0.75% physiological saline to the microbial concentration of 10E6 CFU/ml. In the Muller Hinton agar medium having test chemical, 0.1ml of diluted culture solution was inoculated. MIC was determined after 24 hours of exposure at 37°C. After the exposure of test chemical with different microorganism, MIC was counted. The Minimum Inhibitory Concentration of test chemical on various microorganisms Corynebacterium minutissimum (CM), Arthrobacter sp. isolated from Lipo-66,Staphylococcus aureus (IAM-1011, (SA)), Staphylococcus epidermidis var. (SE) and Escherichia coli (ATCC 11775, (EC) was determine to be >2000 mg/l (inoculum 10E6 CFU/plate) after 24 hours exposure with test chemical.

 

 

Above study further supported by the third weight of evidence report from peer reviewed journal. Toxicity to micro-organisms study was conducted using five different microorganisms. The study was performed for 24 hrs at 37°C.Test organism Staphylococcus aureus (IAM-1011, SA) was purchased from Institute of Applied Microbiology, Tokyo university. Escherichia coli(ATCC 11775, (EC)) was purchased from Institute of Medical Science, Tokyo university. Corynebacterium minutissimum (ATCC 23348, (CM)) and Staphylococcus epidermis var. (SE) were gifted from the Department of Dermatology, University of Pennsyvania. Arthrobacter sp. was isolated from Lipo-66. Culture dish of 35 X 10 mm dimension was used as a test vessel. Test chemical solutions were prepared in either ethyl alcohol or DMSO. Muller Hinton agar was used as a test medium. Test bacteria were pre-propagated with sensitivity test broth of NISSUI using shaking culture. Incubated mediums were diluted using 0.75% physiological saline to the microbial concentration of 10e6 CFU/ml. Test medium containing the test chemical was inoculated using 0.1 ml of diluted culture solution. MIC was determined after 24 hrs at 37°C. Based on the effect of test chemical on the growth inhibition of five different organisms such as Corynebacterium minutissimum, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermis, Arthrobacter spp. after the exposure period of 24 hours, the MIC value was determined to be > 2000 mg/l.

 

Thus, on the basis of above all studies on different microorganisms, the MIC was determined to be > 2000 mg/l.