4-phytase

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 420 (Acute Oral Toxicity - Fixed Dose Method)

Deviations:

no

GLP compliance:

yes

Test type:

fixed dose procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Active enzyme of 4-phytase (CAS 9001-89-2, IUBMB 3.1.3.26)

Molecular formula:

Not applicable, see remarks.

IUPAC Name:

Active enzyme of 4-phytase (CAS 9001-89-2, IUBMB 3.1.3.26)

Constituent 2

Reference substance name:

Protein as a constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available

IUPAC Name:

Protein as a constituent of enzyme deriving from the fermentation or extraction process

Constituent 3

Reference substance name:

Carbohydrates constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available. See remarks.

IUPAC Name:

Carbohydrates constituent of enzyme deriving from the fermentation or extraction process

Constituent 4

Reference substance name:

Inorganic salts as a constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available. See remarks.

IUPAC Name:

Inorganic salts as a constituent of enzyme deriving from the fermentation or extraction process

Constituent 5

Reference substance name:

Lipids as a constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available. See remarks.

IUPAC Name:

Lipids as a constituent of enzyme deriving from the fermentation or extraction process

Test material form:

liquid

Details on test material:

% Total Organic Solids: 25.27%

Test animals

Species:

rat

Strain:

other: HanTac:WH (Wistar Hannover GALAS)

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Taconic Europe A/S, DK-4623 Lille Skensved, Denmark
- Females (if applicable) nulliparous and non-pregnant: not specified
- Age at study initiation: not specified
- Weight at study initiation: 149 - 160 g
- Fasting period before study: overnight
- Housing: The animals were kept in transparent polycarbonate cages (floor area: 1500 cm² Height 21cm) with two in each cage. The cages were cleaned and the bedding changed at least twice a week.
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21°C ±3°C
- Humidity (%): 55% ±15%.
- Air changes (per hr): 10 air changes per hour
- Photoperiod (hrs dark / hrs light): cycle of 12 hours light and 12 hours darkness

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

DOSAGE PREPARATION: The test item was thawed in the refrigerator (+2 - +8°C) overnight. According to the Sponsor, the test item formulation was stable for at least 7 days when stored at +2 - +8°C in the dark. The dose formulation was the undiluted test item.

MAXIMUM DOSE VOLUME APPLIED: Dose volume was 8.09 mL/kg of the undiluted test item.

The starting dose level was based on information from the Sponsor. One female animal was treated with 2000 mg total protein/kg body weight. As no evident signs of toxicity were observed in the animal, the main study was carried out at this dose level.

Doses:

2000 mg total protein/kg body weight (equivalent to of 2143.32 mg enzyme concentrate dry matter/kg bw or 1264.74 mg active enzyme protein/kg bw)

No. of animals per sex per dose:

4

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Each animal was observed 15 minutes and 1, 3, and 6 hours after administration and daily thereafter for 14 consecutive days for clinical signs and weight measured on Days 1, 2, 3, 8, and 15.
- Necropsy of survivors performed: yes

Food was withheld for a 3-hour period after treatment.

Results and discussion

Preliminary study:

One female was dosed at 2000 mg total protein/kg body weight. Animal gained weight during study. No clinical signs were observed. No abnormalities in post-mortem inspection. The preliminary study animal was included in the main study.

Effect levels

Effect levels 1

Sex:

female

Dose descriptor:

LD50

Effect level:

>= 1 264.74 mg/kg bw

Based on:

other: active enzyme protein

Effect levels 2

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 143.32 mg/kg bw

Based on:

other: enzyme concentrate dry matter

Mortality:

No mortality was observed.

Clinical signs:

other: No clinical signs were observed.

Gross pathology:

No abnormalities were observed.

Applicant's summary and conclusion

Interpretation of results:

Category 5 based on GHS criteria

Conclusions:

No signs of toxicity were observed among the 5 animals treated with 2000 mg total protein/kg body weight (equivalent to of 2143.32 mg enzyme concentrate dry matter/kg bw or 1264.74 mg active enzyme protein/kg bw)

Executive summary:

The objective of this study was to assess the toxicity of the test substance when administered as a single oral dose followed by an observation period of 14 days. The study was conducted in accordance with OECD Guideline 420. The study was initiated with a sighting study using one female animal. The dose volume administered was 8.09 mL/kg of the undiluted test item, corresponding to 2000 mg total protein/kg body weight.

 

On the basis of the results of the sighting study, the main study was performed in four additional female rats given a dose of 2000 mg total protein/kg body weight. The total number of animals in the main study included the female animal treated at the same dose level (2000 mg total protein/kg body weight) in the sighting study. No clinical signs were observed among the animals and the body weight gain during the study was normal. The post-mortem inspection of the animals treated with 2000 mg total protein/kg body weight revealed no abnormalities. The dose of  2000 mg total protein/kg body weight is equivalent to of 2143.32 mg enzyme concentrate dry matter/kg bw or 1264.74 mg active enzyme protein/kg bw.