火龙果茎多糖在护手霜中的应用及性能评价

Application and properties of the polysaccharide from red pulp pitaya stem in hand creams

以火龙果茎多糖为研究对象,研究了其结构特征和对护手霜特性的影响。采用水提醇沉法提取火龙果茎多糖,选择蒽酮-硫酸法测定多糖含量、高效液相色谱法分析单糖组成及硫酸-咔唑法测定糖醛酸含量,并评价火龙果茎多糖对护手霜特性(如抗氧化能力、保湿性能和流变学性质)的影响。火龙果茎多糖含量为(346.88±9.05)mg/g,主要是由甘露糖、鼠李糖、半乳糖醛酸、葡萄糖、木糖、半乳糖和阿拉伯糖组成,其中以半乳糖含量最高(70.89±0.38)mg/g,各单糖摩尔比为0.13∶1.27∶1.31∶0.31∶0.19∶3.94∶1.02;火龙果茎多糖中糖醛酸含量为38.76%±1.99%。在抗氧化能力和保湿性能试验中证实,火龙果茎多糖能有效增强护手霜的DPPH自由基清除能力和保湿性能;在流变学性质分析中,火龙果茎多糖的添加不会改变护手霜的稳定性。

The structural characteristics of pitaya stem polysaccharide(PSP)were analyzed.PSP was used as raw material to study its effects on hand creams.The PSP was extracted by hot water extraction and alcohol precipitation method.The total carbohydrate content of PSP was determined by anthrone-sulfuric acid method,and the uronic acid content of PSP was determined by sulfuric acid-carbazole method.The monosaccharide composition of PSP was analyzed by high performance liquid chromatography with diode array detector(HPLC-DAD)after 1-phenyl-3-methyl-5-pyrazolone derivatization(PMP).Different concentrations of PSP were used to prepare hand cream samples.The antioxidant capacity,moisturizing ability and rheological properties of the hand cream samples were evaluated in vitro.The total carbohydrate content of PSP is(346.88±9.05)mg/g and the uronic acid content of PSP is 38.76%±1.99%.The PSP consists of mannose,rhamnose,galacturonic acid,glucose,xylose,galactose and arabinose in the following molar ratios:0.13∶1.27∶1.31∶0.31∶0.19∶3.94∶1.02.Among all the monosaccharides,galactose content is the highest in PSP with(70.89±0.38)mg/g.A positive correlation between the concentration of PSP and the DPPH radical scavenging capacity is confirmed for the hand creams.The DPPH radical scavenging capacity of the hand cream prepared with 10%PSP is several times better than that of PSP-free hand cream.The moisturizing ability of the hand cream is also increased with the increase of PSP concentration.The moisturizing rates of the hand cream prepared with different concentrations of PSP are around 80%within 24 h and 60%within 48 h,while the moisturizing rate of PSP-free hand cream is only 58.17%±1.45%within 24 h and 38.09%±1.56%within 48 h.In the steady-state flow curves and oscillation strain curves of rheological properties,the viscosity of all hand cream samples significantly decreases in relatively low shear rate,whereas the viscosity is low and tends to a fixed value in high shear rate.The PSP added does not change the stability of the hand cream.