Enzymatic hydrolysis products of Ophiopogon japonicus, Liliaceae, root

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Septembre 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The study was conducted according to an internationally recognised method, and under GLP. No deviation was reported. Test substance is adequately specified. Therefore full validation applies.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes

Remarks:

GLP Compliance Programme (inspected on October 13 and 14 2014/ signed on April 8, 2015)

Type of method:

capillary method

Key result

Decomposition:

yes

Remarks:

Signs of degradation of the substance were observed between 89.8°C (363.0 K) and 170.3°C (443.5 K)* (mean of two independent determinations). At the end of the test, the test item did not change back into the original state but remained caramelised.

Decomp. temp.:

>= 89.8 - <= 170.3 °C

Remarks on result:

other:

Remarks:

In the Main Test, no melting point and boiling point/range was detected.

Pre-Test

First Pre-Test in a test tube

First a small amount was heated in a test tube in the aluminium block in order to approximate

temperature of melting and boiling of the test item or the degradation / decomposition

of the test item.

The following observations were done:

Table 4.2/1 Observations of the Pre-Test in a test tube

Observations	Temperature*
Colourless condensate visible	103.3 °C
Test item bloated appearance like beaten eggs white with a hard dome	136.8 °C
Colour change visible to yellow	154.6 °C
Test terminated, test item looks like cappuccino with milk froth	188.2 °C

*All temperatures were stated without the deviation of the thermometer. Under the dome the test item is liquid.

No melting / boiling point can be approximate with the first Pre-Test, performed in a test tube. However, signs of degradation of the test item were observed. The test item did not change back into the original state at the end of the first Pre-Test (irreversible change of appearance and colour).

Second Pre-Test in a capillary

The capillary tube containing the test item was set into the aluminium block with quick increase

in temperature ( < 10K/min) in order to better apprehend the melting range or the

degradation range of the test item.

The following observations were done:

Table 4.2/2 Observations of the Pre-Test in a capillary tube

Observations	Temperature
Capillary set into the aluminium block	21.5 °C
The test item bloated upward a bit	68.1 °C
Test item shrivelled together, a colourless condensate was visible	102.9 °C
Test item bloated appearance like beaten eggs white with a hard dome	134.9 °C
Colour change visible to yellow	148.7 °C
Test item dark brown, heating plate turned off	196.5 °C

*All temperatures were stated without the deviation of the thermometer

In the second Pre-Test performed in a capillary tube, no melting of the substance was observed, but signs of degradation of the substance were observed. At the end of this Pre- Test, the test item did not change back into the original state but remained caramelised.

Main Test

At first, the capillary tube containing the test item was set into the block at 85.1 °C. The block was heated gently. The test item shrivelled together at 89.4 °C the test was terminated because the performance criteria were not fulfilled (The test should be started at least 10 °C below the expected melting point). A second test was performed the capillary tube containing the test item was set into the block at 75.0 °C. The test item shrivelled together at 89.9 °C. At 130.4 °C the test item bloated and appeared as yellow. As the test item colour was slightly brown and the test sample expanded up in the capillary tube at 179.6 °C the test was stopped. Unfortunately the start of the colour change was missed therefore this test was not guilty. Therefore both tests were repeated.

The capillary tube containing a fresh test item sample was then set into the aluminium block at 75.0 °C (third determination) and at 75.1 °C (fourth determination). The block was heated gently at a temperature gradient of </= 1 °C/min.

The following observations were recorded:

Table 4.2/3 Observations of the Main Test :

Observations	First Determination*	Second Determination*
Capillary set into the aluminium block	75.0 °C	75.1 °C
Test item shrivelled together	89.9 °C	90.1 °C
Colour change visible to yellow	118.7 °C	117.8 °C
expanded up in the capillary tube colour slightly brown	151.9 °C	150.9 °C
Test stopped Colour brown like caramel	167.8 °C	173.2 °C

* All measured values from the observations are without subtraction of the thermometer deviation

In the Main Test, no melting point and boiling point/range was detected. However, signs of degradation of the substance were observed between 90°C (363.2 K) and 170.5°C (443.7 K)* (mean of two independent determinations). At the end of the test, the test item did not change back into the original state but remained caramelised.

RESULTS AND VALIDITY

Result Test Item OF14 AT

In all performed determinations (Pre-Tests and Main Test), no melting point and boiling point/range were detected and signs of degradation of the substance were observed. In all determinations, the test item did not change back into the original state but remained caramelised. According to the Main Test, the degradation of the substance was observed between 90°C (363.2 K) and 170.5°C (443.7 K) (mean of two independent determinations).

Validity

No validity criteria could be considered as the test item decomposed.

Conclusions:

No melting point was recorded.

Executive summary:

The melting point of the test substance was tested under GLP according to EU A1 and OECD 102, by capillary method. No melting point was recorded.

First, a small amount was heated in a test tube in the aluminium block. Second, the capillary tube containing the test item was set into the aluminium block with quick increase in temperature. In both Pre-Tests, signs of degradation of the substance were observed. The determination of the Main Test for the melting point was performed in duplicate. In both determinations, no melting point and boiling point/range were detected and signs of degradation of the substance were observed.

In all determinations, the test item did not change back into the original state but remained caramelised.

According to the Main Test, the degradation of the substance was observed between 90°C (363.2 K) and 170.5°C (443.7 K) (mean of two independent determinations).

Description of key information

No melting point was recorded

Additional information

A fully reliable experimental study, conducted according to a recognized EU/OECD method and under GLP, is available.

No melting point was recorded but the degradation of the substance was observed between 90°C (363.2 K) and 170.5°C (443.7 K) before melting.