Absolute of Jasmine (Jasminum grandiflorum) obtained from Jasmine concrete by ethanol extraction

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018-06-26 to 2018-08-24

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

GLP compliance:

no

Type of method:

flask method

Water solubility:

0.23 g/L

Conc. based on:

test mat. (dissolved fraction)

Loading of aqueous phase:

0.991 g/L

Incubation duration:

8 d

Temp.:

21.5 °C

pH:

ca. 5

Water solubility:

0.78 g/L

Conc. based on:

test mat. (dissolved fraction)

Loading of aqueous phase:

5.02 g/L

Incubation duration:

8 d

Temp.:

21.5 °C

pH:

ca. 5

Preliminary Tests

The preliminary tests revealed that already relatively low amounts of the sample material were visually not soluble even in large amounts of water from a subjective point of view.

Results

Saturation in Flask 1:

An overview of the sampling of flask 1 together with the determined content of TC as well as the corresponding deviation compared to each previous measurement in the range of the equilibrium are summarised in Table 1 (clearly indicating the equilibration of saturation)

Table 1: Sampling dates and determined sample contents of flask 1

sampling no.	test duration [d]	TC [mg/L]	deviation from previous measurement [%]
1	0	234	-
2	1	444	-
3	2	447	-
4	3	449	-
5	6	437	-2.8
6	7	438	+0.2
7	8	440	+0.5
	mean (4-7)	441.0	-
	SD (4-7)	5.7	-
	RSD (4 -7) [%]	1.3	-

Agitation of all flasks was stopped on the ninth day as the last four control points in flask 1 differed no more than 15 % and showed no upward tendency.

Examination of Flasks 2 - 7:

Final examination of flasks 2 to 7 was conducted after 24 hours of temperature equilibration (21.5 °C +- 0.3 °C). The final concentration data obtained from TC measurements are given in Table 2 together with the initial weigh-in for each flask, the measured pH values, the resulting applied loading and the final concentration of the sample in water. The determined carbon content in flask 7 (blank) remained unconsidered for final calculations as it was found to be negligibly low (no significant influence on the final results).

The loading is calculated by weight of test item / volume of water used (here: 50 mL). The final concentration values for the sample were calculated by consideration of the carbon content of the native sample material, which was found to be 77.6 %.

Table 2: Final examination of flasks 2 to 7

flask no.	initial weigh-in [mg]	applied loading [g/L]	pH value (approx.) [-]	resulting TC concentration [mg/L]	final concentration of sample in water [g/L]
2	49.54	0.991	5	182	0.23
3	99.64	1.993	5	325	0.42
4	154.09	3.082	5	441	0.57
5	201.24	4.025	5	528	0.68
6	250.99	5.020	5	603	0.78
7	-	0	5	4	-
				mean (flask 2 -6)	0.54 (*1)
				SD (flask 2- 6)	0.19 (*1)
				RSD (flask 2 -6) [%]	37.9 (*1)

(*1) mean concentration, standard deviation SD and relative standard deviation RSD are only given in accordance to the guideline; these values appear to be meaningless upon the interpretation of the results

Conclusions:

Due to the test item's chemical composition (mixture of different components, each having different physico-chemical properties and thus different individual water solubilities) the water solubility is indicated as 13.37 % (w/w) of the sample material is soluble at 21.5 °C +- 0.3 °C (linear dependence of the water solubility of the sample on the applied loading).

Executive summary:

The water solubility of the test item was determined according to OECD 105 using the flask method. The water solubility of the test item was determined at 21.5 °C +- 0.3 °C and depends on the loading of the sample material in water within the examined loading range of 0.991 g/L to 5.020 g/L. In that range, sample concentrations of 0.23 g/L to 0.78 g/L were found. The dependency between solubility and loading was found to be linear in the examined range of loadings with a slope value of 0.1337. The chemical composition of the sample should be considered for interpreting such behavior: the sample consists of a mixture of different compounds, each having different physico-chemical properties and thus different individual water solubilities. As a result, the linear dependence of the water solubility of the sample on the applied loading may be interpreted as an indication that 13.37 % (w/w) of the sample material is soluble at 21.5 °C +- 0.3 °C.

Description of key information

The water solubility of the test item was determined at 21.5 °C +- 0.3 °C and depends on the loading of the sample material in water within the examined loading range of 0.997 g/L to 5.020 g/L. In that range, sample concentrations of 0.23 g/L to 0.78 g/L were found. The dependency between solubility and loading was found to be linear in the examined range of loadings with a slope value of 0.1337. The chemical composition of the sample should be considered for interpreting such behavior: the sample consists of a mixture of different compounds, each having different physico-chemical properties and thus different individual water solubilities. As a result, the linear dependence of the water solubility of the sample on the applied loading may be interpreted as an indication that 13.37 % (w/w) of the sample material is soluble at 21.5 °C +- 0.3 °C.