L-arginine phosphate

Toxicity to microorganisms

Administrative data

Endpoint:

toxicity to microorganisms, other

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1990-10-15 to 1991-12-04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

DIN 38412-8 (Pseudomonas Zellvermehrungshemmtest)

Version / remarks:

Draft at performance of test

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Arginine

EC Number:

200-811-1

EC Name:

Arginine

Cas Number:

74-79-3

Molecular formula:

C6H14N4O2

IUPAC Name:

arginine

Test material form:

not specified

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A stock solution was prepared. From this stock solution, appropriate dilutions were prepared in test medium to yield the final test concentrations
- Controls: no
- Evidence of undissolved material (e.g. precipitate, surface film, etc): visually

Test organisms

Test organisms (species):

Pseudomonas putida

Details on inoculum:

- Supplier: Deutsche Sammlung für Mikroorganismen (DSM), Braunschweig, Germany
- Strain: Berlin 33/2
- Laboratory culture: Cultivation according to draft standard by TNO
- Method of cultivation: Cultivation according to draft standard
A pre-culture was prepared by inoculating the appropriate medium with a suspension prepared from the stock culture. After 16 h incubation at 21 °C +/- 1°C its optical desity was 1.514. the bacterial inoculum suspension had an optical density of 0.423 after centrifugation, resuspension and diluation with test medium measured in a 10 mm polystyrene disposable cuvette with a Pye Unicam PU 8600 spectromter at 436 nm.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

16 h

Test conditions

Hardness:

Not applicable

Test temperature:

20.5 °C

pH:

6.94 to 7.08 at beginning of test. 6.6 in the control series at the end of test. 5.33 to 8.02 in the test series at the end of test.

Dissolved oxygen:

No data

Salinity:

Not applicable

Nominal and measured concentrations:

Nominal test concentrations: 0.10, 0.32, 0.56, 1.0, 1.8, 3.2, 5.6 and 10 g/kg.

Details on test conditions:

TEST SYSTEM
- Test vessel: conical test flasks
- Type: closed
- Material, size, headspace, fill volume: 200 ml
- Aeration: no
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 6

TEST MEDIUM
The composition of the media was:
preculture [mg/l] test medium[mg/l]
NaNo3 500 560
K2HPO4 120 130
KH2PO4 60 66
Yeast extract 50 --
C6H12O6.H2O 2000 2220
MgSO4.7H2O 400 440
Iron citrate 1.0 1.1

OTHER TEST CONDITIONS
- Adjustment of pH: with diluted HCl
All flasks were incubated in an orbital shaker at 130 rpm

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Optical density (OD), after 16.5 h

Results and discussion

Effect concentrations

Duration:

16.5 h

Dose descriptor:

EC10

Effect conc.:

> 10 other: g/kg

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Remarks:

expressed by optical density (OD)

Details on results:

- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: no
- Effect concentrations exceeding solubility of substance in test medium: no

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

L-Arginine did not show toxicity to microorganisms in a test according to (draft) DIN 38 412, L8 with the test organism Pseudomonas putida. The EC 10 after 16 h was > 10 g/kg.