Licheninase

Endpoint summary

Description of key information

The acute oral toxicity of licheninase has not been studied. However, a read-across approach was used with enzymes alpha-amylase, cellulase and xylanase, all belonging to glcosidases (IUB 3.2.1).

For alpha-amylase: No signs of toxicity were observed among the rats treated with a single oral dose of 1911 mg total organic solids/kg, which was the highest possible dose at dose volume 20 mL/kg, using the undiluted test item.

For cellulase: The acute oral lethal dosage (LD50) of cellulase was greater than 2880 mg Total Organic Solids (TOS)/kg bw.

For xylanase: No signs of toxicity were observed among the rats treated with a single oral dose of 2102 mg total organic solids/kg, which was the highest possible dose at dose volume 20.6 mL/kg, using the undiluted test item.

Due to the similarities between the enzymes, it can be concluded that the toxicity of licheninase will be similar to the above-mentioned enzymes.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

Reference 1

Endpoint:

acute toxicity: oral

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

June 29 to August 31, 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Due to the similarity between the two enzymes, this study can be used as read-across for licheninase.

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Version / remarks:

Dec. 2001

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

- Source: Charles River, Germany
- Fasting period before dosing: Overnight
- Housing: A maximum of 6 animals per sex per cage, transparent macrolon cages
- Weight at time of dosing: between 168-174 g
- Housing: In animal room with control of temperature and humidity
- Diet: Standard diet ad libitum
- Water: Tap water ad libitum
- Acclimatization period: 5 days
- Temperature (°C): 20-24°C
- Humidity : 45-70 %

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 20 mL/kg

Doses:

Undiluted test material 20 mL/kg body weight, corresponding to 1911 mg total Total organic solids (TOS)/kg body weight (limit testing)

No. of animals per sex per dose:

6 (only females)

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observations for clinical signs of effect: within 1 hour and within 4 hours after dosing and at least once daily throughout the observation period. Weighing: just prior to dosing on day 0 and on days 3, 7 and 14
- Necropsy of survivors performed: yes

Key result

Sex:

female

Dose descriptor:

LD0

Effect level:

> 1 911 mg/kg bw

Based on:

other: Total organic solids

Mortality:

No mortality.

Clinical signs:

No clinical signs.

Body weight:

Body weights and body weight gains normal.

Gross pathology:

No abnormalities.

Interpretation of results:

GHS criteria not met

Conclusions:

No signs of toxicity were observed among the rats treated with a single oral dose of 1911 mg total organic solids/kg, which was the highest possible dose at dose volume 20 mL/kg, using the undiluted test item.

Executive summary:

The objective of this study was to assess the acute toxicity of Alpha-amylase when administered as a single oral dose to rats followed by an observation period of 14 days. The purpose of the study was to satisfy regulatory demands because the enzyme is used for production of food in EU.

The study was conducted in accordance with the OECD Guideline No 423, “Acute Oral Toxicity – Acute Toxic Class method”. The design of the limit test was used. The test item was supplied as a brown liquid ready to use. The dose volume administered was 20 mL/kg body weight corresponding to 1911 mg/kg body weight, based on the Total Organic Solids (TOS) content of the test substance.

No mortality or clinical signs were observed after treatment and the overall body weight gain during the study was considered to be normal. The necropsy revealed no abnormalities.

In conclusion, no signs of toxicity were observed among the rats treated with a single oral dose of 1911 mg TOS/kg body weight, which was the highest possible dose at dose volume 20 mL/kg, using the undiluted test item.

Reference 2

Endpoint:

acute toxicity: oral

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

From September 20, 1994 to October 12, 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Due to the similarity between the two enzymes, this study can be used as read-across for licheninase.

Qualifier:

according to guideline

Guideline:

other: Annex to Commission Directive 92/69/EEC of 31 July 1992. B1. L 383 A/110. OECD Guidelines for Testing of Chemicals, 401, 1987.

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

- Source: Møllegaard Breeding Center, Ejby, Denmark.
- Fasting period before dosing: approx 21 hrs overnight
- Housing: Five animals per cage, transparent polycarbonate cages Type IV, 590 MAK dimensions 59 x 38 x 20 cm
- Weight at time of dosing: between 112-121 g (males), 108- 127 g (females)
- Housing: In animal room with control of temperature and humidity
- Diet: Standard diet ad libitum
- Water: Acidified tap water ad libitum
- Acclimation period: 5 days
- Temperature (°C): 19-21°C
- Humidity : 33-80 %

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Remarks:

Test batch used as is. Control animals were dosed with tap water.

Details on oral exposure:

Undiluted test material, dose volume 20 mL/kg bw, corresponds to 2.88 g TOS/kg body weight (limit test), based on the conservative assumption that the specific gravity of the undiluted test batch is 1 g/mL.

No. of animals per sex per dose:

5

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observations for clinical signs of effect: Frequently during day 1 (dosing day) and then once a day. Weighing on Days 1, 8 and 15
- Animals were fasted from the evening before dosing and until 4 hrs after dosing
- Necropsy of survivors performed: yes

Statistics:

No

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 880 mg/kg bw

Based on:

other: TOS (Total Organic Solids)

Mortality:

Male: 2880 mg TOS/kg bw; Number of animals: 5; Number of deaths: 0
Female: 2880 mg TOS/kg bw; Number of animals: 5; Number of deaths: 0
No control animals died during the study.

Clinical signs:

Signs of toxicity related to dose levels:
No clinical signs were observed in the dose group or in the control group.

Body weight:

Neither body weights nor body weight gains were influenced in any of the groups.

Gross pathology:

Effects on organs:
No treatment related findings were observed in the dose group or the control group. Histopathology was not performed.

Interpretation of results:

Category 5 based on GHS criteria

Conclusions:

In conclusion, the acute oral lethal dosage (LD50) of cellulase was greater than 2880 mg Total Organic Solids (TOS)/kg bw.

Executive summary:

The study was conducted in accordance with the OECD Guideline No 401, “Acute Oral Toxicity”. The limit test procedure was used. The test item was supplied as a brown liquid ready to use. The dose volume administered was 20 mL/kg of the undiluted test material.

No clinical signs were observed and the overall body weight gain during the study was considered to be normal. The post-mortem inspection revealed no abnormalities.

In conclusion, no signs of toxicity were observed among the rats treated with a single oral dose of 2880 mg Total Organic Solids (TOS)/kg.

Reference 3

Endpoint:

acute toxicity: oral

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

June 04 - August 13, 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Due to the similarity between the two enzymes, this study can be used as read-across for licheninase.

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Version / remarks:

Adopted 2001

Deviations:

no

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: In-house bred animals
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 10 weeks
- Weight at study initiation: 189.64 - 203.03 g
- Fasting period before study: The animals were not fasted prior to dose administration
- Housing: Three animals were housed in a standard Polysulfone cage (size: L 430 x B 285 x H; 200 mm) with stainless steel mesh top grill. Clean sterilized paddy husk was provided as bedding material. Sterilized paper shreds were provided as nesting material for enrichment.
- Diet (e.g. ad libitum): Nutrilab rodent feed (Manufactured by Provimi Animal Nutrition India Pvt Ltd.) ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: 7-9 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19.6 to 22.4°C
- Humidity (%): 50 to 64%
- Air changes (per hr): 12 to 15 air changes per hour
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 22 June 2015 To: 15 July 2015

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

Undiluted test material

Doses:

The animals were given two dosages of 10.3 mL/kg body weight with an interval of 4 hours between each administration (a total dose of 2102 mg TOS/kg body weight)

No. of animals per sex per dose:

6

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observation for clinical signs of toxicity and mortality at 30 to 40 min, 1 hr (±10 min), 2 hrs (±10 min), 3 hrs (±10 min) and 4 hrs (±10 min) after each administration on Day 1 and thereafter, once daily for clinical signs of toxicity and twice daily for mortality during the 14 days observation period. Individual animal body weight was recorded on Day 1 (before test item administration for first time), Day 7 and Day 14 during the observation period.
- Necropsy of survivors performed: yes

Statistics:

No

Sex:

female

Dose descriptor:

other: Fixed dose method - no effects were seen

Effect level:

> 20.6 mL/kg bw

Based on:

test mat.

Key result

Sex:

female

Dose descriptor:

other: Fixed dose method - no effects were seen

Effect level:

> 2 102 mg/kg bw

Based on:

other: Total Organic Solids (TOS)

Mortality:

No animals died during the study.

Clinical signs:

No clinical signs of toxicity and mortality were observed during the 14 days observation period.

Body weight:

No effect was observed on the body weights.

Gross pathology:

Effects on organs:
No gross pathological changes observed

Interpretation of results:

Category 5 based on GHS criteria

Conclusions:

No signs of toxicity were observed among the rats treated with a single oral dose of 2102 mg total organic solids/kg, which was the highest possible dose at dose volume 20.6 mL/kg, using the undiluted test item.

Executive summary:

The objective of this study was to assess the acute toxicity of Xylanase when administered as a single oral dose to six rats followed by an observation period of 14 days. The purpose of the study was to satisfy regulatory demands because the enzyme is used for production of food in China.

The study was conducted in accordance with the OECD Guideline No 423, “Acute Oral Toxicity – Acute Toxic Class method”. The design of the limit test was used. The test item was supplied as a brown liquid ready to use. The dose volume administered was 20.6 mL/kg body weight corresponding to 2102 mg/kg body weight, based on the Total Organic Solids (TOS) content of the test substance.

No mortality or clinical signs were observed after treatment and the overall body weight gain during the study was considered to be normal. The necropsy revealed no abnormalities.

In conclusion, no signs of toxicity were observed among the rats treated with a single oral dose of 2102 mg TOS/kg body weight, which was the highest possible dose at dose volume 20.6 mL/kg, using the undiluted test item.