PROCESS FOR PREPARING SURFACTANT

Abstract

A process for the preparation of C4 to C24 alkyl polyglycosides by the use of an enzyme to react C4 to C24 alkyl glycoside with a glycosyl donor containing monosaccharide residues, wherein the C4 to C24 alkyl polyglycosides have a mole-average degree of polymerization (mean DP) of the glycoside chains of greater than 1.5 units. The C4 to C24 alkyl polyglycosides are particularly useful in personal care formulations.

Claims

1. A process for the preparation of C4 to C24 alkyl polyglycosides by reacting with an enzyme a C4 to C24 alkyl glycoside and a glycosyl donor comprising monosaccharide residues, wherein (a) the reaction mixture comprises (i) monosaccharide residues in the glycosyl donor to alkyl glycoside at a molar ratio of less than 40.0:1.0, and optionally (ii) alkyl glycoside at greater than or equal to 1.0 wt %; (b) greater than or equal to 3.0 wt % of the monosaccharide residues in the glycosyl donor are transferred to the alkyl glycoside (glycoside units conversion); and (c) the reaction product comprises alkyl polyglycoside optionally comprising (i) greater than 0.10 mole fraction of alkyl monoglycoside (DP1), and/or (ii) a mole-average degree of polymerization (mean DP) of the glycoside chains of greater than or equal to 1.5 units.

2. A process of reacting with an enzyme; (i) a glycosyl donor comprising monosaccharide residues; and (ii) an alkyl glycoside of the formula R.sub.m-G.sub.n, wherein R is an alkyl group comprising m carbon atoms, m is 4 to 24, G is at least one monosaccharide residue, and n is the number of monosaccharide residues; in a reaction mixture to form a reaction product comprising; (iii) an alkyl polyglycoside of the formula R.sub.p-G.sub.q, wherein R is an alkyl group comprising p carbon atoms, p is 4 to 24, G is at least one monosaccharide residue, q is the number of monosaccharide residues, and the mean value of q (mean DP) is greater than or equal to 1.5, q=(n+s) wherein n is defined in (ii) and s is the increase in the number of monosaccharide residues that occurs during the enzyme reaction, and the mean value of s is greater than or equal to 0.5; and (iv) greater than or equal to 3.0 wt % of the monosaccharide residues in the glycosyl donor are transferred to the alkyl glycoside (glycoside units conversion) during the enzyme reaction.

3. The process according to claim 1 wherein the molar ratio of monosaccharide residues in the glycosyl donor to alkyl glycoside is less than 20.0:1.0.

4. The process according to claim 3 wherein the molar ratio of monosaccharide residues in the glycosyl donor to alkyl glycoside is less than 6.0:1.0.

5. The process according to claim 1 wherein the glycoside units conversion is greater than or equal to 15.0 wt %.

6. The process according to claim 5 wherein the glycoside units conversion is greater than or equal to 35.0 wt %.

7. The process according to claim 1 wherein the mean DP of the alkyl polyglycosides is greater than or equal to 1.8 units.

8. The process according to claim 7 wherein the mean DP of the alkyl polyglycosides is greater than or equal to 2.1 units.

9. The process according to claim 1 wherein the reaction product comprises less than 15.0 wt % cyclodextrin.

10. The process according to claim 9 wherein the reaction product comprises less than 5.0 wt % cyclodextrin.

11. The process according to claim 1 wherein the glycosyl donor is cyclodextrin, optionally b-cyclodextrin.

12. The process according to claim 1 wherein the reaction mixture comprises greater than or equal to 8.0 wt % alkyl glycoside.

13. The process according to claim 1 wherein the reaction mixture comprises greater than or equal to 10.0 wt % glycosyl donor.

14. The process according to claim 1 comprising at least one of (i) the molar ratio of monosaccharide residues in the glycosyl donor to alkyl glycoside is 0.8 to 2.5:1.0, and/or (ii) the glycoside units conversion is greater than or equal to 50.0 wt %, and/or (iii) the mean DP of the alkyl polyglycosides is 1.9 to 2.3 units, and/or (iv) the reaction product comprises less than 4.0 wt % cyclodextrin.

15. The process according to claim 14 comprising at least two of (i) to (iv).

16. The process according to claim 14 comprising at least three of (i) to (iv).

17. The process according to claim 14 comprising all of (i) to (iv).

18. A composition comprising C4 to C24 alkyl polyglycosides wherein the amount of alkyl monoglycoside (DP1) is greater than 0.10 mole fraction and the mole-average degree of polymerization (mean DP) of the glycoside chains is greater than or equal to 1.8 units.

19. The composition according to claim 18 wherein the mean DP is greater than or equal to 2.1 units.

20. The composition according to claim 18 wherein the amount of DP1 is 0.30 to 0.68 mole fraction.

21. The composition according to claim 18 wherein the amount of alkyl diglycoside (DP2) is 0.10 to 0.45 mole fraction.

22. (canceled)

23. (canceled)

24. (canceled)

25. (canceled)

Description

EXAMPLES

Example 1

[0142] 31 kg of maltodextrin having a DE value of 1 was charged to 39 kg of water in a reaction vessel at room temperature and the reaction mixture was agitated with stirring until the maltodextrin was dissolved. The maltodextrin solution was then drummed off. 10 kg of 50 wt % aqueous solution of lauryl glucoside was charged to 20 kg of water in the reaction vessel as a free-flowing liquid (at approx. 50° C.) and the stirring speed adjusted to avoid excessive foaming. HCl solution was charged to the reaction vessel to adjust the pH to 6.5. The previously prepared maltodextrin solution was then charged to the reaction vessel with stirring. The temperature was increased to 65° C. and stirrer speed adjusted to avoid excessive foaming. When the temperature had reached 65° C., 0.5 kg of Thermoanaerobacter sp CGTase (EC 2.4.1.19) enzyme preparation (equivalent to 17 KNU-CP per kg of reaction mixture) was added to the reaction vessel. The reaction mixture was stirred and the reaction continued for 20 hours. The reaction mixture was then heated to 95° C., kept constant at this temperature for 2.5 hours to inactivate the enzyme, cooled to 40-50° C. with stirring and the pH adjusted to 11.5 using 50% sodium hydroxide solution. A sample of the crude reaction mixture was taken, subjected to the test procedures described herein, and exhibited the following properties;

[0143] a) Reaction mixture: [0144] i) Alkyl polyglucoside=6.2 wt %. [0145] ii) α-Cyclodextrin=2.3 wt %. [0146] iii) β-Cyclodextrin=3.4 wt %. [0147] iv) Linear oligosaccharides=4.6 wt %. [0148] v) Foam height=130 mm (PEG-80 sorbitan laurate=92, cocamidopropyl betaine=78).

[0149] b) Alkyl polyglucoside: [0150] i) DP1=0.35 mole fraction. [0151] ii) DP2=0.23 mole fraction. [0152] iii) DP3=0.15 mole fraction. [0153] iv) DP4 to DP10=0.25 mole fraction. [0154] v) DP11 to DP15=0.02 mole fraction. [0155] vi) Mean DP=2.9 glucose units. [0156] vii) Increase in mean DP=1.8 glucose units. [0157] viii) Glucose conversion=12.5 wt %.

[0158] c) Linear oligosaccharides: [0159] i) DP1 to DP8=2.6 wt %. [0160] ii) DP9 and above=2.0 wt %. [0161] iii) Mean DP=3.0 glucose units.

[0162] The remaining reaction mixture was left in the reaction vessel without stirring at room temperature for at least 24 hours until precipitation occurred. After precipitation had completed, the precipitate was collected by separating the solid phase from the solution by centrifugation. The liquid supernatant was then subjected to flash chromatography to remove any residual sugar component, including linear oligosaccharides and cyclodextrins, using an Isolera system from Biotage equipped with a Snap Ultra C18 column (Biotage) with a volume of 654 ml. The supernatant was diluted with 99.5% ethanol to a final ethanol concentration of 20 wt % and then loaded on the column which had been pre-equilibrated with 20% ethanol. The column was then washed with equilibration solution to remove unbound sugars and protein from the column. The alkyl polyglucoside was then eluted by a step-wise change of mobile phase to 80% ethanol, followed by a final step with 99.5% ethanol. Most of the product was recovered in the 80% ethanol step and all alkyl polyglucoside containing fractions were pooled. The ethanol from the pooled fractions was removed by evaporation in a Büchi rotavapor and the remaining water was removed by freeze drying to produce a white, free-flowing powder of alkyl polyglucoside reaction product, which was subjected to the test procedures described herein, and exhibited the following properties; [0163] i) DP1=0.35 mole fraction. [0164] ii) DP2=0.23 mole fraction. [0165] iii) DP3=0.18 mole fraction. [0166] iv) DP4 to DP10=0.23 mole fraction. [0167] v) DP11 to DP15=0.002 mole fraction. [0168] vi) Mean DP=3.0 glucose units.

Example 2

[0169] 100 grams of a 50 wt % solution of lauryl glucoside and 300 grams of maltodextrin having a DE value of 6 were mixed with 0.6 litres of water in a 2-litre reaction vessel with top stirring. The pH was adjusted to 7 with HCl and the temperature was then increased to 45° C. When the temperature had reached 45° C., 2.0 g of Bacillus macerans CGTase (EC 2.4.1.19) enzyme preparation (equivalent to 2400 U per kg of reaction mixture) was added and the reaction allowed to proceed at constant temperature for 24 hours. The reaction mixture was heated to 95° C. for 2 hours to inactivate the enzyme, and then cooled to ambient temperature. The reaction mixture was then subjected to flash chromatography to remove any residual sugar component using a C18-Silica column (400 g, Biotage). The entire reaction mixture was diluted with 99.5% ethanol to a final concentration of 20% ethanol, before loading on the column, previously equilibrated with 20% ethanol. The column was washed with 16 column volumes of 20% ethanol for removal of the residual sugar. 6 column volumes of 40% ethanol were then applied for elution of the bound enzyme. Finally, the alkyl polyglycoside reaction product was eluted with 80% ethanol and concentrated by means of freeze drying, yielding a white free-flowing powder. The resulting alkyl polyglucoside reaction product was subjected to the test procedures described herein, and exhibited the following properties; [0170] i) DP1=0.38 mole fraction. [0171] ii) DP2=0.25 mole fraction. [0172] iii) DP3=0.14 mole fraction. [0173] iv) DP4 to DP10=0.23 mole fraction. [0174] v) Mean DP=2.6 glucose units. [0175] vi) Increase in mean DP=1.5 glucose units. [0176] vii) Glucose conversion=10.8 wt %. [0177] viii) Cholesterol Solubility=17.8 mg ml.sup.−1 (PEG-80 sorbitan laurate=0.7 mg ml.sup.−1, NatraGem™ S140=3.5 mg ml.sup.−1, decyl glucoside=5.2 mg ml.sup.−1).

Example 3

[0178] 1.9 kg of a 50 wt % aqueous solution of lauryl glucoside was mixed with 1.6 kg of water at 50° C. under constant stirring in a reaction vessel. Another 3.4 kg of water was added and the temperature was increased to 65° C. 1.9 kg of α-cyclodextrin was gradually added together with 1.0 kg of water, and the reaction mixture was agitated with stirring for 30 minutes until all components were dissolved. HCl solution was charged to the reaction vessel to adjust the pH to 7.0. 0.1 kg of Thermoanaerobacter sp CGTase (EC 2.4.1.19) enzyme preparation (equivalent to 34 KNU-CP per kg of reaction mixture) was then added to the reaction mixture which was agitated and the reaction continued for 5 hours. The reaction mixture was then heated to 95° C., kept constant at this temperature for 3 hours to inactivate the enzyme, cooled to 40-50° C. with stirring and the reaction mixture recovered from the reaction vessel. The alkyl polyglucoside reaction product was subjected to the test procedures described herein, and exhibited the following properties;

[0179] a) Reaction mixture: [0180] i) Alkyl polyglucoside=17.8 wt %. [0181] ii) α-Cyclodextrin=5.5 wt %. [0182] iii) β-Cyclodextrin=4.7 wt %. [0183] iv) Linear oligosaccharides=0.3 wt %.

[0184] b) Alkyl polyglucoside: [0185] i) DP1=0.38 mole fraction. [0186] ii) DP2=0.21 mole fraction. [0187] iii) DP3=0.15 mole fraction. [0188] iv) DP4 to DP10=0.24 mole fraction. [0189] v) DP11 to DP15=0.02 mole fraction. [0190] vi) Mean DP=2.9 glucose units. [0191] vii) Increase in mean DP=1.8 glucose units. [0192] viii) Glucose conversion=45 wt %.

Example 4

[0193] 135.6 g of a 50 wt % aqueous solution of lauryl glucoside was mixed with 77.1 g of water in a 400 ml reaction vessel under stirring. To the solution was added 56 g of β-cyclodextrin undecahydrate powder and the reaction mixture was agitated with stirring until the 3-cyclodextrin dissolved. 30.9 ml of HCl solution was charged to the reaction vessel to adjust the pH to 6.0 and the temperature was raised to 75° C., after which 0.45 ml of an enzyme preparation containing Thermoanaerobactersp. CGTase (EC 2.4.1.19) was added to the reaction vessel. The reaction mixture was stirred and the reaction continued for 24 hours. The reaction mixture was then heated to 95° C., kept constant at this temperature for 2.5 hours to inactivate the enzyme and then cooled. A sample of the crude reaction mixture was taken, subjected to the test procedures described herein, and exhibited the following properties;

[0194] a) Reaction mixture: [0195] i) Alkyl polyglucoside=33 wt %. [0196] ii) α-Cyclodextrin=1.0 wt %. [0197] iii) β-Cyclodextrin=2.6 wt %. [0198] iv) Linear oligosaccharides=1.0 wt %.

[0199] b) Alkyl polyglucoside: [0200] i) DP1=0.52 mole fraction. [0201] ii) DP2=0.23 mole fraction. [0202] iii) DP3=0.11 mole fraction. [0203] iv) DP4 to DP10=0.13 mole fraction. [0204] v) DP11 to DP15=0.003 mole fraction. [0205] vi) Mean DP=2.1 glucose units. [0206] vii) Increase in mean DP=1.0 glucose units. [0207] viii) Glucose conversion=60 wt %. [0208] ix) Foam height=108 mm (PEG-80 sorbitan laurate=92, cocamidopropyl betaine=78).

[0209] c) Linear oligosaccharides: [0210] i) DP1 to DP8=0.9 wt %. [0211] ii) DP9 and above=1.0 wt %. [0212] iii) Mean DP=2.6

[0213] d) Essential oils solubility:

[0214] Lemon oil, lavender oil, tea tree oil and patchouli oil (1 wt %) mixtures with 7 wt % alkyl polyglucoside all remained clear with no phase separation after 5 hours (lemon oil and lavender oil mixtures were white and cloudy, and had phase separated after five hours using 7 wt % lauryl glucoside as solubilizer).

[0215] The above examples illustrate the improved properties of the process and compositions according to the present invention.