阅读说明：本技术 一种羧甲基化木聚糖的制备方法及其应用 (Preparation method and application of carboxymethylated xylan ) 是由 关媛 孙鹤飞 林桂源 甘志琴 李霞 单杨 于 2019-10-26 设计创作，主要内容包括：本发明公开了一种羧甲基化木聚糖的制备方法及其应用。称取木聚糖加入蒸馏水中,制得分散液,在分散液中加入质量百分比浓度为20%的氢氧化钠水溶液和异丙醇,室温下搅拌3 h,再加入氯乙酸和质量百分比浓度为20%的氢氧化钠水溶液,得到混合溶液,在70℃下搅拌反应3~5 h,然后降至室温后用1 mol/L的盐酸调节pH值至7,流水透析24 h,浓缩,冷冻干燥,即制得羧甲基化木聚糖。本发明的羧甲基化木聚糖应用于抗氧化类保健品和化妆品。本发明得到的羧甲基化木聚糖制备工艺,操作简单,便于大规模生产,同时通过本发明制备得到的不同取代度羧甲基化木聚糖能够一定程度的提高抗氧化活性,在抗氧化类保健品和化妆品中具有广阔的应用前景。(The invention discloses a preparation method of carboxymethylated xylan and application thereof, wherein xylan is weighed and added into distilled water to prepare dispersion liquid, sodium hydroxide aqueous solution and isopropanol with the mass percentage concentration of 20% are added into the dispersion liquid, the mixture is stirred for 3 hours at room temperature, chloroacetic acid and sodium hydroxide aqueous solution with the mass percentage concentration of 20% are added to obtain mixed solution, the mixed solution is stirred and reacted for 3 ~ 5 hours at 70 ℃, then the mixed solution is cooled to room temperature, the pH value is adjusted to 7 by 1mol/L hydrochloric acid, and the mixed solution is dialyzed for 24 hours by running water, concentrated and frozen and dried to obtain the carboxymethylated xylan.)

1. A preparation method of carboxymethylated xylan is characterized by comprising the following specific steps:

(1) weighing 100 mg of xylan, and adding the xylan into 1 mL of distilled water to prepare dispersion liquid;

(2) adding 10 mL of 20% sodium hydroxide aqueous solution and 20 mL of isopropanol into the dispersion liquid prepared in the step (1), stirring for 3 h at room temperature, and then adding 3 ~ 5 g of chloroacetic acid and 10 mL of 20% sodium hydroxide aqueous solution to obtain a mixed solution;

(3) and (3) stirring the mixed solution prepared in the step (2) at 70 ℃ for reaction for 3 ~ 5 h, then cooling to room temperature, adjusting the pH value to 7 by using 1mol/L hydrochloric acid, dialyzing with running water for 24 h, concentrating, and freeze-drying to obtain the carboxymethylated xylan.

2. Use of the carboxymethylated xylan prepared by the preparation method according to claim 1, wherein the carboxymethylated xylan is used in antioxidant health care products and cosmetics.

Technical Field

The invention relates to a modification process of carboxymethylation of xylan and research on antioxidant activity of the modification process, and particularly relates to a preparation method and application of carboxymethylation xylan.

Background

Xylan exists in plant cell walls and accounts for 15% ~ 35% of the dry weight of plant cells, has various biological activities and is reflected in the aspects of oxidation resistance, blood fat reduction, immune regulation and the like.

Research reports that reasonable chemical modification of polysaccharide can obviously improve the biological activity of polysaccharide. Common chemical or molecular modification processes are carboxymethylation, alkylation, acetylation, sulfation, phosphorylation, and the like. The carboxymethylation modification has many advantages, such as economical and easily-obtained reagents, no toxic products, easily-controlled reaction process and the like. The Parvath study showed that carboxymethylation modification of galacto-mannans resulted in significant solubility improvements. The carboxymethylated tiger milk polysaccharide is obtained by the wild goose and the like through modification, the solubility is also obviously improved to be more than 30 mg/mL, and the absorption rate of the organism to the carboxymethylated tiger milk polysaccharide is greatly increased. The xylan is subjected to carboxymethylation modification to obtain xylan derivatives with different structures, and the xylan derivatives can be endowed with new biological activity. Therefore, optimizing a stable xylan carboxymethylation modification method and researching the biological activity of the carboxymethyl xylan are of great significance.

According to the invention, carboxymethylation modification is carried out on xylan, the structure of the xylan is determined, the preparation process of the carboxymethylation xylan is optimized, and the antioxidant activity of carboxymethylation xylan with different degrees of substitution is relatively researched.

Disclosure of Invention

The invention aims to provide a preparation method and application of carboxymethylated xylan.

The preparation method of the carboxymethylated xylan comprises the following specific steps:

(1) 100 mg of xylan was weighed and added to 1 mL of distilled water to prepare a dispersion.

(2) And (2) adding 10 mL of 20% sodium hydroxide aqueous solution and 20 mL of isopropanol by mass into the dispersion prepared in the step (1), stirring at room temperature for 3 h, and adding 3 ~ 5 g of chloroacetic acid and 10 mL of 20% sodium hydroxide aqueous solution by mass to obtain a mixed solution.

(3) And (3) stirring the mixed solution prepared in the step (2) at 70 ℃ for reaction for 3 ~ 5 h, then cooling to room temperature, adjusting the pH value to 7 by using 1mol/L hydrochloric acid, dialyzing with running water for 24 h, concentrating, and freeze-drying to obtain the carboxymethylated xylan.

The carboxymethylated xylan of the invention is applied to antioxidant health care products and cosmetics.

The preparation process of the carboxymethylated xylan is simple to operate and convenient for large-scale production, and meanwhile, the carboxymethylated xylan with different degrees of substitution prepared by the preparation process can improve the antioxidant activity to a certain extent, and has wide application prospects in antioxidant health-care products and cosmetics.

Drawings

FIG. 1 is a graph showing the effect of carboxymethylated xylan with different degrees of substitution on scavenging superoxide anion radicals in the examples of the present invention.

FIG. 2 is a graph showing the effect of carboxymethylated xylan with different degrees of substitution on scavenging hydroxyl radicals in the examples of the present invention.

FIG. 3 is a graph showing the effect of carboxymethylated xylan with different degrees of substitution on DPPH radical scavenging in examples of the present invention.

FIG. 4 shows the effect of carboxymethylated xylans of different degree of substitution on the reducing power in examples of the present invention.

Detailed Description