1-[4-[[2-O-(6-deoxy-α-L-mannopyranosyl)-β-D-glucopyranosyl]oxy]-2,6-dihydroxyphenyl]-3-(3-hydroxy-4-methoxyphenyl)propan-1-one

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From October 24th to October 26th, 2016.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - Shake Flask Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Partition coefficient type:

octanol-water

Analytical method:

photometric method

Key result

Type:

log Pow

Partition coefficient:

0.67

Temp.:

20 °C

pH:

> 6.2 - < 6.7

Table 1. Results of measurements at 20.0 ºC.

Vial number	1	2	3	4	5	6
Temperature, ºC	20.0	20.0	19.9	19.9	20.1	20.1
Volume of added stock solution, mL	1	1	1	1	1	1
Volume of water, mL	5	5	6.7	6.7	3.3	3.3
Volume of 1-octanol, mL	4	4	2.3	2.3	5.7	5.7
Volume of 1-octanol phase /volume of water phase	1:1	1:1	1:2	1:2	2:1	2:1
Neohesperidin Dihydrochalcone concentration in water phase, g/L	0.086	0.085	0.107	0.108	0.068	0.068
Neohesperidin Dihydrochalcone concentration in 1-octanol phase, g/kg	0.471	0.463	0.600	0.603	0.393	0.380
Neohesperidin Dihydrochalcone concentration in 1-octanol phase, g/L	0.389	0.382	0.495	0.497	0.324	0.314
Mass of Neohesperidin Dihydrochalcone in water phase (x1E3), g	0.430	0.425	0.717	0.724	0.224	0.224
Mass of Neohesperidin Dihydrochalcone in 1-octanol phase (x1E3), g	1.945	1.910	1.634	1.640	2.171	2.104
Mass of Neohesperidin Dihydrochalcone in both phases (x1E3), g	2.375	2.335	2.351	2.364	2.395	2.328
Added mass of test item (x1E3), g	2.495	2.495	2.495	2.495	2.495	2.495

Table 2. Measured pH values of the water phase.

Vial number	1	2	3	4	5	6
pH before test	6.25	6.24	6.15	6.16	6.69	6.69
pH after test	6.25	6.25	6.16	6.15	6.70	6.69

Table 3. Determination of test item content in water phase and 1-octanol phase.

Sample	Weight of the sample [mg]	Dilution [mL]	Cp [mg/mL]	Average peak area Ap	X [g/kg]
1/w	1481.	5	296.32	0.933	0.086
2/w	1490.85	5	298.17	0.935	0.085
3/w	1501.45	5	300.29	1.181	0.107
4/w	1509.15	5	301.83	1.198	0.108
5/w	1506.35	5	301.27	0.762	0.068
6/w	1513.05	5	302.61	0.764	0.068
stock	329.95	10-1-5	6.60	0.738	3.024
1/o	329.55	10	32.96	0.578	0.471
2/o	317.25	10	31.73	0.548	0.463
3/o	336.9	10	33.69	0.747	0.600
4/o	325.2	10	32.52	0.726	0.603
5/o	315.8	10	31.58	0.466	0.393
6/o	336.6	10	33.66	0.479	0.380

Table 4. Calculated values logarithm to base 10 of partition coefficient 1-octanol/water.

Vial number	1	2	3	4	5	6
volume 1-octanol phase/volume of water phase	1:1		1:2		2:1
Pow = C1-octanol/Cwater	4.52	4.49	4.63	4.60	4.76	4.62
log Pow = log(C1-octanol/Cwater)	0.66	0.65	0.67	0.66	0.68	0.66
Average log Pow + standard deviation	0.66 ± 0.01		0.67 ± 0.01		0.67 ± 0.01
Average log Pow + standard deviation	0.67 ± 0.01

Conclusions:

The value of log Kow of the test item at 20ºC is 0.67 ± 0.01 (pH 6.2 - 6.7).

Executive summary:

The determination of the test substance's partition coefficient 1-octanol/water was carried out according to OECD TG 107 and EU A.8, shake flask method, under GLP conditions. Water and 1 -octanol phases were mutually saturated and the amount of test item in each phase was determined by UV-VIS spectrophotometry. Taking into account the solubility of the test substance in water and its solubility in 1-octanol, the partition coefficient was calculated. The partition coefficient 1-octanol/water (log Pow) at 20.0 °C of the test item is 0.67 ± 0.01 (pH 6.2 - 6.7).

Description of key information

Key study. Method according to OECD 107 / EU Method A.8 (shake flask method), GLP study. The partition coefficient 1-octanol/water (log Pow) at 20.0 °C of the test item is 0.67 ± 0.01 (pH 6.2 - 6.7).

Key value for chemical safety assessment

Log Kow (Log Pow):

0.67

at the temperature of:

20 °C

Additional information

The determination of the test substance's partition coefficient 1-octanol/water was carried out according to OECD TG 107 and EU A.8, shake flask method, under GLP conditions. Water and 1 -octanol phases were mutually saturated and the amount of test item in each phase was determined by UV-VIS spectrophotometry. Taking into account the solubility of the test substance in water and its solubility in 1-octanol, the partition coefficient was calculated. The partition coefficient 1-octanol/water (log Pow) at 20.0 °C of the test item is 0.67 ± 0.01 (pH 6.2 - 6.7).