METHOD FOR CATALYTICALLY SYNTHESIZING FURANEOL

Abstract

A method for catalytically synthesizing furaneol, which uses a specific peptide to function as a catalyst, uses rhamnose to function as a raw material, and uses an organic solvent and a phosphate buffer to function as a reaction solvent to be co-heated to prepare furaneol.

Claims

1. A method for catalytically synthesizing furaneol, comprising: (1) mixing rhamnose, phosphate buffer with a pH of 5-7, organic solvent, and a peptide, heating to a reflux state after a nitrogen gas replacement, and reacting until a content of the furaneol in an organic phase no longer changes to obtain a material, wherein a reaction temperature is 60-120° C., a reaction time is 3-6 hours, the peptide consists of 2-20 amino acids and the peptide has a molecular weight of no more than 2000 Daltons; (2) leaving the material obtained in step (1) to stand to be cooled down to obtain an organic phase and an aqueous phase; and (3) recycling an organic solvent in the organic phase obtained in step (2), then distilling under a reduced pressure to obtain the furaneol, and recycling the aqueous phase.

2. The method according to claim 1, wherein the rhamnose defines at least one of a levorotation configuration or a dextrorotation configuration.

3. The method according to claim 1, wherein the rhamnose comprises at least one crystal water.

4. The method according to claim 1, wherein the peptide comprises at least one of alanyl glutamine, diglycine, L-carnosine, glutathione, collagen tripeptide, fish collagen, or soybean oligopeptide.

5. The method according to claim 1, wherein the organic solvent comprises at least one of butyl acetate, ethyl acetate, toluene, benzene, or xylene.

6. The method according to claim 1, wherein the organic solvent is butyl acetate.

7. The method according to claim 1, wherein the phosphate buffer is a NaH.sub.2PO.sub.4/Na.sub.2HPO.sub.4 buffer solution.

8. The method according to claim 1, wherein the pH of the phosphate buffer is 6-7.

9. The method according to claim 1, wherein a mass ratio of the rhamnose to the peptide is 1:0.1-5.

10. The method according to claim 1, wherein the reaction temperature is 100° C. and the reaction time is 3 hours in step (1).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG. 1 illustrates a gas chromatography (GC) spectrum of a furaneol prepared in Embodiment 1 of the present disclosure and after recrystallization (ethyl ester is used as a dilution solvent).

[0024] FIG. 2 shows further information regarding the gas chromatography (GC) spectrum of FIG. 1.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The present disclosure will be further described in combination with the accompanying embodiments and drawings.

Embodiment 1

[0026] (1) 100 g of rhamnose monohydrate, 600 g of NaH.sub.2PO.sub.4/Na.sub.2HPO.sub.4 buffer solution with a pH of 6-7, 500 g of butyl acetate, and 95.8 g of alanyl glutamine are mixed, heated to a reflux state after a nitrogen gas replacement, and reacted until a content of furaneol in an organic phase does not change. A reaction temperature is 100° C. and a reaction time is 3 hours.

[0027] (2) The material obtained in step (1) is left to stand and cooled to room temperature (e.g., 20-30° C.) to obtain an organic phase and an aqueous phase.

[0028] (3) The organic phase obtained in step (2) is concentrated using rotary evaporation to recycle butyl acetate and to be further distilled in reduced pressure to obtain 25 g of furaneol (a yield is 35%, a GC content is 90% (weight/weight), which reaches 99.7% (weight/weight) after a recrystallization using 95% ethanol. Referring to FIG. 1, a melting point is 77-80° C.). The aqueous phase is recycled for use.

Embodiment 2

[0029] The alanyl glutamine obtained in step (1) is replaced with other peptides, and the reaction time and a mass ratio of a peptide to the rhamnose are changed. The rest is the same as Embodiment 1. Experimental results are illustrated in Table 1.

TABLE-US-00001 TABLE 1 Reaction conditions for catalytically preparing the furaneol using the rhamnose under different peptides Catalyst/ Reaction Embodi- Rhamnose time Yield ments Catalyst (mass/mass) (hour) (%)  1 Alanyl glutamine 0.958 3 35  2 Alanyl glutamine 0.958 6 34  3 Diglycine 0.58 3 33  4 Diglycine 0.58 6 32  5 L-carnosine 1 3 34  6 L-carnosine 1 6 28  7 Glutathione 1.35 3 36  8 Glutathione 1.35 6 35  9 Collagen tripeptide 1 3 15 10 Collagen tripeptide.sup.a 1 6 20 11 Fish collagen.sup.b 1 3 16 12 Soybean 1 3 18 oligopeptides.sup.c Remark: .sup.aThe collagen tripeptide is a tripeptide consisting of glycine, proline (or hydroxyproline), and another amino acid. A structure of the collagen tripeptide is simply represented as Gly-x-y, and an average molecular weight of the collagen tripeptide is 280 Daltons. .sup.bThe fish collagen is extracted from fresh skins or scales of deep-sea cods using bioenzymic directing degrading technology and is mainly I-typed collagen. The product is rich in 19 amino acids and has a molecular weight of 800-1200 Daltons (The fish collagen is obtained from Jiangsu Xinrui Biological Technology Co., Ltd). .sup.cThe soybean oligopeptides is prepared by an enzymatic hydrolysis of soybean protein and is a short-chain polypeptide mainly comprising 2-10 amino acids and having a molecular weight of below 1000 Daltons (The soybean oligopeptides are obtained from Jiangsu Xinrui Biological Technology Co., Ltd.).

[0030] The aforementioned embodiments are merely some embodiments of the present disclosure, and the scope of the disclosure is not limited thereto. Thus, it is intended that the present disclosure cover any modifications and variations of the presently presented embodiments provided they are made without departing from the appended claims and the specification of the present disclosure.