The Research On Flavonoids And Volatile Compounds In Siberian Apricot Flowers

Siberian apricot flowers were selected as raw materials in this paper. Flavonoids and volatile compounds in Siberian apricot flowers were studied.The method of extracting, separating and purificating total flavonoids, the determination of activity and initial structure of total flavonoids were studied.The volatile components of different blooming stages(early flowering, full-bloom and late flowering)were identified by simultaneous distillation extraction(SDE)and Gas Chromatography-Mass Spectrometer(GC-MS).1. Optimization of extraction method. The best conditions of flash extraction optimized by single factor tests and response surface methodology were obtained as liquid/material ratio 100 mL/g,ethanol concentration 76%,extraction temperature 67℃ and extraction time 5 min and under this condition the extraction yield was 144.68 mg/g.The value of relative error was 0.02% compared with the theoretical value, which showed that the extraction method optimized was reliable and had practical application value.2. Optimization of the method of separating total flavonoids with X-5 macroporous resin. The best conditions of separating optimized by orthogonal test based on single factor tests were as follows: loading velocity 1 mL/min,pH 2, sample concentration 0.7 mg/mL,5 bed volume(BV)water washing,5 BV of 95% ethanol as the eluent,desorption velocity 2 mL/min.After the separation,the average adsorption and recovery rate was 93.46% and 88.15%, respectively.The purity of total flavonoids could be improved from 30.18% to 93.12%.3. Initial determination and analysis of the structure of total flavonoids in Siberian apricot flowers.After separated with macroporous resin and extracted by ethyl acetate,flavonoids in Siberian apricot flowers were further purificated using Sephadex LH-20 and identified by high performance liquid chromatography-mass spectrometry(HPLC-MS). The results showed that ethyl acetate extraction section wound most likely contain rutin and chlorogenic acid.4. The determination of activity of total flavonoids in Siberian apricot flowers.The antioxidant activity of separated and unseparated total flavonoids in Siberian apricot flowers were investigated by measuring scavenging effect on DPPH ·and OH·,total reduction capacity, total antioxidant capacity and the inhibitory effect on tyrosinase activity was studied by measuring the rate of tyrosinase catalyzed L-DOPA oxidation taking Vc and β-arbutin as positive controls. The results showed that separated and unseparated total flavonoids in Siberian apricot flowers had a certain antioxidant activity. After separation, the antioxidant activity was improved obviously; the inhibitory effect on tyrosinase of separated and unseparated total flavonoids in Siberian apricot flowers was better than β-arbutin but worse than Vc. Their half maximal inhibitory concentration(ICso) were 2.24,3.08 mg/mL, respectively.5. The research on the anti-aging activity of total flavonoids in Siberian apricot flowers in Drosophila melanogaster.The results showed that total flavonoids in Siberian apricot flowers(0.1,0.5 mg/mL)could extremely significantly extend the average life span of Drosophila melanogaster and maximum life span(p<0.01), and significantly improve catalase activity(CAT)(p<0.05), superoxide dismutase activity(SOD)(p<0.01),significantly reduce malondialdehyde content(MDA)(p<0.01);total flavonoids in Siberian apricot flowers (0.1,0.5 mg/mL)could effectively resist the damage caused by hydrogen peroxide and paraquat.6. The identification of volatile components of different blooming stages (early flowering, full-bloom and late flowering).The results showed that total 28 kinds of volatile components were identified in three different blooming stages, containing aldehyde (11 kinds), ketone (4 kinds), esters (4 kinds), alcohols (4 kinds), paraffin (4 kinds) and other kinds (1 kind).Aldehyde was the main composition. Its content increased at first and then decreased as the flowers bloomed. Benzaldehyde content was the highest, up to 80-90%.Benzaldehyde, nonanal,2,6,6-trimethyl-2-cyclohexene-1,4-dione, benzyl alcohol, linalool, hexadecane, heneicosane and octacosane were unique aroma components in Siberian apricot flowers.