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Hawthorn is an important medicinal and edible plant resources, many domestic and foreign scholars have conducted research has shown, contains a variety of biologically active components, so they have a variety of pharmacological effects. Early this laboratory pointed out in the study of Chinese hawthorn, hawthorn fruit, the main active ingredient as the the oligomeric original anthocyanins (OPC) polymer is of epicatechin its formation. We first discovered red fruit acids (eucomic acid) hawthorn prepared and isolated from hawthorn fruit that has the characteristic aroma of hawthorn fruit ingredients. This thesis, in the previous study basis, to carry out the following work: (1) the establishment of a gas chromatography - mass spectrometry determination of the red hawthorn its products acid analysis method. Hawthorn fruit and their products after anhydrous ethanol extract with sulfuric acid, methanol (12% v / v) solution esterification in 80 ° C water bath for 1 h after the HP-5ms capillary column separation, tandem mass spectrometry of red fruit acid qualitative and quantitative analysis. Chromatography mass spectrometry conditions: initial 60 ℃ for 1 min, rose to 20 ℃ / min to 160 ° C for 1 min, then rose to 20 ℃ / min to 250 ° C and maintained for 3 min. Helium flow rate of 1 ml / min, split ratio 20:1, injection 1μL, inlet temperature of 250 ° C, the interface temperature of 250 ° C. Ionization electron bombardment (EI), electron energy 70 eV, ion source temperature of 230 ° C, the the quadrupole temperature is 150 ° C. Under these conditions, red acid retention time of 12 min, the recovery rate of the method in 87% to 102%, the relative standard deviation of 3.1% to 5.6%, and is limited to 10 times the signal-to-noise ratio, limit of quantification was 0.7μg (samples the red acid content). The method is fast, accurate and highly sensitive. Determined using GC-MS method development hawthorn actual samples of red fruit acid content the hawthorn fruit content of 255 mg / kg, of haw jam 7.2 mg / kg, the two hawthorn fruit juice were 17.9,15.4 mg / kg, hawthorn Soup 5.1 mg / kg, the the hawthorn cake 7.8 mg / kg, and data show significantly lower red fruit acid content than fresh fruit in hawthorn products, we think that the the red acid content as hawthorn and its products an important quality indicator of this is not only to provide a scientific basis for the evaluation of the intrinsic quality of the hawthorn fruit, more importantly, is able to guide the the hawthorn process to develop reasonable parameters, to maintain the greatest degree of the active ingredient of hawthorn products. (2) DPPH · Radical clear between the activity of the five hawthorn yellow alkanol compounds. The results show that hawthorn flavanol compounds has a strong scavenging DPPH · free radical, the EC50 values ??between 1.4 ~ 1.7 mg / L, were lower than several reference antioxidants (VC, Trolox, TBHQ and fat-soluble tea polyphenols). Clear the stronger with the increase of the degree of polymerization of the flavanol compounds, and links different ways, different radical scavenging capacity, which to the proanthocyanidins link C-4, C-6 B5 clear than C-4, C-8 are linked procyanidin B2. In order to better understand the flavanol compounds between free radical scavenging capacity, measured flavanol compounds with DPPH · radical reaction of the second-order rate constant k2 gt size proanthocyanidins D1; ??procyanidins C1 gt; procyanidins B5 gt; procyanidins B2 gt; epicatechin. Hawthorn flavanol extract Antioxidant test results showed that the extract of hawthorn flavanols can effectively inhibit lipid peroxidation effect is an effective free radical scavenger and antioxidant, the antioxidant capacity of the grease in a dose relationship, i.e., with increasing doses of lipid peroxidation capacity decreased. Add 0.1% hawthorn flavanols effect is equivalent to 0.02% TBHQ. VC, citric acid, fat-soluble tea polyphenols flavanol extract of hawthorn in fat have a synergistic antioxidant effects, the composite effect of antioxidants than single use. With the health effects of natural antioxidants to replace synthetic antioxidants future food additives, health food industry trends, and has a broad development prospects.
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