Persimmion belonging to Ebenaceae DiospyrosL is Deciduous tree.It distributes in torrid and temperate zone.It is abundant in flavone,tannis and Carotene etc which are bioactive components,so it is worthy of developing. This paper mainly conducted the extraction,purification and deodorant effect of polyphenols from persimmon peel.The results were showed that:The experiment used the traditional solvent extraction.Based on single factor tests,thogonal test was done.The optimum extraction conditions were that the concentration of acet was 50%,extraction temperature is 55℃,the extraction time was 105min and the ratio of the persimmon peel to solvent was 1:16.Under the optimal conditions the extraction yield could reach 71.16%.Through the absorption of static and dynamic curve of static studying in the six kinds of macroporous resin.Resoult showed that HP-20 resin had excellent absorption and desorption properties.The dynamic absorption conditions were flow speed 2BV/h,column density 2.91mg/mL and pH4.8. Through the research on gradient elution,it showed that:40%ethanol eluted the purity which could reach 32.04%.Through the bacterial experiments,three samples had effects of restraining bacterium.The sample B had better antibacterial effect than the other two samples.The elimination effect enhanced with the concentration of sample increasing.The minimum inhibition concentration(MIC)of sample B on Escherichia coli,Staphy lococus and Saccharomyces cerevisiae were listed as follows:250mg/mL,125mg/mL,250mg/mL.The minimum sterilization quality fractions(MBC)were:500mg/mL,250mg/mL,500mg/mL.Combining apparatus with sensory analysis Method.The results showed that:the extract of Polyphenol had effect on ammonia,trimethlamin,sulfureted hydrogen,formaldehyde and indole.The sample B had the best effect on trimethlamin and the worst effect on formaldehyde.This might relate Polyphenol purity,the structure and character of the smelt substance.Apparatus and sensory analysis methods could show the effect of deodorization exactly.Through the further purification by Sephdaex LH-20,the Polyphenol purity of sample B-2 was 53.64%.The deodorant rate of it on trimethlamine was 62.37%(2mg/mL).Samples were detected by UV spectrum.After compared to the characterristic absorption of polyphenol,the sample was supposed to contain the polyphenol.By using the High performance liquid chromatography (HPLC),we selected three kinds of phenolics standards to determine small molecular phenolics in camelliia chryscath.The result showed that sample B-2 might containe gallic acid,the caffeine and the table caffeine.
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The Study on Extraction of Rosmarinic Acid from Rosemary and Their Antioxidant Ability of the Rosemary Antioxidant
Rosemary（Rosmarinus officinalis L.）, an evergreen shrub, which is a natural spiceberry of the family Labiatae, contained many kinds of bio-active substances. One of these substances was rosmarinic acid, which had very strong antioxidant ability. In this paper, the technics of extraction and purification of rosmarinic acid （RosA） from rosemary and the antioxidant ability of the extract were studied.Firstly, the extraction of rosmarinic acid from rosemary with microwave and ultrasonic wave was studied. The results showed that the optimal extracting technological conditions were as follows: 20 mesh（comminuted size, mesh）, 15% （ethanol concentration, v/v）, ratio of liquid to material （5:1）, 10 min（the time of ultrasonic cells broken）, 540w （the power of microwave）,4 times （extracting times） and 6 min each time. Under these conditions, the extracting rate of rosmarinic acid could reach 94.54%. It showed that this method had the advantages of short extracting time, high yield and low-cost for extraction of rosmarinic acid.Secondly, the optimal conditions of purification were studied experimentally. The extraction liquid was clarified by ceramic micro-filter and used X-5 macroporous absorption resin to concentrate rosmarinic acid. The optimal adsorption conditions were determined: When the adsorption speed was 4 mL·min-1, the resin could absorb 1500 mL extraction liquid , and 1300mL 75% ethanol was used to desorb.Thirdly, the gained concentration solution was purified by normal butanol, and the best condition of extraction was: When the solid concentration was 14.29%, pH=3, extraction time was 20min, the volume ratio of solution to normal butanol was 1:1.5, the extraction times was 2.Finally, the crystallization method was used to the further purify to gain the pure products. The qualitative analysis by HPLC showed that the content of the final rosmarinic acid products was 96.82%（w/w）.Furthermore, the antioxidant activities of rosemary extract was studied. The rosmarinic acid products had a good antioxidant ability though it showed slightly lower reducing power and scavenging ability on superoxide radical(·O-2) than ascorbic acid. And in order to make the best use of rosemary, the lipid-soluble antioxidant was extracted from the material dregs.All in all, the purity of rosmarinic acid products was high. The whole technics were short and easy to undertake in factory which had a good future in industrial application.
Research on Extraction, Physicochemical Property and Antioxidation of Purple Dioscorea Batatas Decne
Dioscorea batatas Decne, an annual or perennial twining liana plant, belongs to dioscorea batatas family. It is mainly distributed in tropical and subtropical areas in Africa, South America, and Southeast Asia. Dioscorea batatas Decne is rich in carbohydrates, and also contains protein, various vitamins, chemicals, indicant, and mucilage which are beneficial to human body. It is bright red, and has developed rhizomes in the shape of a sole, thus named. Its colors vary from white to puce （purple）. Purple ones indicate that they contain certain pigments, belonging to anthocyanin. Anthocyanin, a kind of flavonoid compound, is an edible natural pigment of water-solubility. At present, few researches have been done on the pigment of Dioscorea batatas Decne. Domestic researches have been limited to the separation and extraction of it. In the paper, the writer has made an initial exploration into the separation and extraction of the pigments in purple Dioscorea batatas Decne, and the stability and the biological activity of extracorporeal anti-oxidation have also been studied in the paper, which has provided a theoretical foundation on which to take advantage of anthocyanin, and develop functionality foods from Dioscorea batatas Decne.Based on Orthogonal experiments, the paper first studies the best technological conditions under which to lixiviate pigments of Dioscorea batatas Decne. The results show that pure anthocyanin can be extracted by filtering steep, adsorbing colophony, decompression and cubage reduction, under the condition that 1.5 percent of citric acid ethanol liquor serves as the best lixiviator, which should be heat up under the constant temperature of 60℃for 60 minutes, and the proportion of general materials should be 1:10.At the same time, the paper also studies the stability of the pigment in purple Dioscorea batatas Decne, showing its stability under the condition of pH<3 high acid liquids, and its unstability under the condition of pH > 5 liquids. It possesses certain heat-resistance, but the temperature should not be over 90℃. It has relatively poor lightfastness. Most metal ions will not have great effects on the stability of the pigment, while Al3+、Fe3+ do have great impacts, among which Al3+、Fe3+ tend to increase the absorbency of the pigment.In the paper, two extracorporeal anti-oxidation models have been adopted to study the extracorporeal anti-oxidation of pigment in purple Dioscorea batatas Decne so that the potential of pigment as a function gene of anti-oxidation can be fully understood. The results indicate that pigment in purple Dioscorea batatas Decne possesses considerably strong ability to eliminate·OH and·O2-, and its ability has so much to do with its thickness.
Citrus fruit is one of the biggest yield of fruit in the world,peel is their maily byproduct and it takes 20～40% output in the total citrus.The research use citrus fruit peel as test material and studied on extration and purification of flavonoids in citrus fruit peels.At the same time,Antioxidation activity was studied. UV spectrophotometer were used to measure the concentration of total flavonoid.The results was reported as following:The article sutdied on different extraction methods:water bath extraction, micro-wave extraction and supersonic extraction. Influencing factor:Ethanol concentration,extracting time, liquid-to-solid ratio, extracting temperature,micrwave power,supersonic power were studied. Through mono-factor anlysis with different extration methods,the results show that supersonic extraction has the optimal rate of extraction. Using central composite rotatable design and second order quadratic equation to determine the optimize process of flavonoids extraction by supersonic.By analyzing the response surface plots and their corresponding contour plots as well as solving the quadratic equation,the optimal processing for supersonic extraction were 62.08% ethanol,62.17min supersonic time,37.59 liquid-solid ratio.The predicted result for the rate of flavonoids extraction was 1.23%. Variance analysis is very significance in the Quadratic equation model.Four macroporous adsorption resin were used to purify flavonoids of citrus citrus peel. Through static adsorption and desorption experiment,using the rate of absorption and desorption as evaluating indicator,finally got AB-8 was the best in the four different resins and the resin got its adsorption equilibrium in five hours,the optimal dynamic adsorption processing parameter of AB-8 resin were flavonoids solution concentration is 1.22mg/mL,pH is 3.5. The optimal dynamic desorption processing parameter are flow rate is 1BV/h, ethanol concentration is 70%. Purity of total flavonoids was increased from 8.7% to 38.5%. AB-8 resin can be used to purify flavonoids of citrus peel.The antioxidation activity of citrus peel flavonoids before purifying and after purifying was studied, The results was reported as following:when flavonoids addition was 0.4mg,the effect of scavenging hydroxyl free radical and superoxide anion free radical were vitamin c>citric acid>purified flavonoids>rough flavonoids, the effect of scavenging DPPH free radical was vitamin c>purified flavonoids>citric acid>rough flavonoids. The effect of scavenging the three free radical was intensified while the addition of puried flavonoids increased,(flavonoids addition between 0.3～1.5mg);The different antioxidant activity was studied in lard oil.The effect of antioxidant was BHT > rough flavonoids > purified flavonoids>rutin>bland.The effect of antioxident in lard oil was intensified while the addition of puried flavonoids increased.
Boron slurry is the solid waste of boron industry, which not only engrosses a great deal of the soil, but also cause hazard to field, groundwater and Atmospheric Environment. About 40 wt% Magnesium Oxide in the boron slurry, which is discharged freely causes Magnesium resource waste greatly. So looking for suitable method for recycling Magnesium, it is not only can gain tremendous economic benefit, but also can improve ecological environment and speed up sustainable development process.At present, the main method for leaching Magnesium from boron slurry is acid leaching. In the course, iron and aluminium impurities dissolve into the leaching liquor, which effects the leaching liquor purity and further use, and should be removed. Traditional method for purification uses Alkali. According to the leaching liquor being acid solution system, The test put forward solid extraction mothod for separating iron and aluminium impuritiesunder under this circumstance. This method has many advantages such as no magnesium loss, renewable recycling use, rapid separation and high efficiency. Subsequently, fine processing of leaching liquor is researched and morphology-homogeneous magnesium hydroxide sulfate whiskers are received, which can be used for Enhancement and flame retardant. The concrete research contents are as follows:1.Study on leaching magnesium from the boron slurry is described. We use hydrochloric acid and sulfuric acid as leaching agent to study the soaking rate of Mg from the boron slurry. The results show that sulfuric acid has higher Mg leaching rate and lower cost comparing with hydrochloric acid. The optimum condition of sulfuric acid leaching is concluded as follow: Using 10 g drying boron slurry as our initial state, the dosage of H2SO4 is 7.92 ml which the dilution rate is 1:3（120 % of the theoretical dosage of H2SO4）, reactive time is 80min, reactive temperature is 70℃, the Mg leaching rate receives 94.2%.2.According to the leaching liquor being acid solution system, We use solvent extraction and solid extraction method for purification reseach, the technical parameters and influencing factors of the solvent extraction technique have been studied. At last, we separate iron and aluminium with self-made solid extraction adsorption column, the technical parameters, the stability and regrowth of the extraction adsorption columnand also have been studied. After solid extraction, The isolation rates of iron and aluminium impurities receive 99.7 % and 99.0 % respectivly. Refined magnesium sulfate solution is received and the magnesium from the boron slurry is separated effectively.3.Preparation of magnesium hydroxide sulfate hydrate whiskers is researched. Using Sodium Hydroxide as precipitant, fine processing of magnesium salt is researched and sector shape 152 model magnesium hydroxide sulfate hydrate whiskers are received by hydrothermal method. The hydrothermal influence factors such as concentration, filling degree, reaction temperature and time have been discussed. The optimum condition of synthesizing is concluded as follow: the concentration of MgSO4 is 0.5-0.8 mol/L, molar ratio of MgSO4 and Mg（OH）2 is 2:1, filling degree is more than 32 %, stirring rate is 600 r/min and reaction temperature and time are 140℃and 4 h respectively.
In this paper, the extraction process, functional property and modification of japonica rice protein are studied. The aim is to improve the functional property and exploit a rice protein product. It provides gist and technological bases for the further development and utilization of rice resources. The main results are as follows:The optimum extraction conditions of Alkali-protease is as follows: temperature 58℃, pH 8.5, the material-liquid ratio 9:1, enzyme/substrate1000 U/g,the time 4h. The ratio of extraction can reach 70.5%, and the purity can reach 66.53%.The rice protein extraction by the physical-Enzymatic, dual enzyme and the two-step method of alkaline–enzyme are studied. The results show that the three methods can increase the extraction rate of rice protein, and the effect of the two-step method of alkaline-enzyme is significant. The optimum extraction conditions of the two-step method of alkaline-enzyme: alkaline extraction, pH11.0, temperature50℃, time 3 h and the material-liquid ratio:8:1; alkali-proteased extraction, temperature: 55℃, pH:8.5, the material-liquid ratio:9:1, enzyme/substrate:750 U/g, the time 2 h. The ratio of extraction can reach 90.21%, and the purity can reach 83.34%.The effect of pH on solubility, emulsifying properties, and foaming properties of two rice protein( alkaline and protease ) are studied.The modification of rice protein by alkaline Nanning alkaline protease is researched. The best modified conditions: enzyme in5000 u/g, pH9.5, temperature 55℃and hydrolysis time 2 h and rice protein has the dissolution rate of 85.45%.The rice protein functional properties of different hydrolysi conditions, are compared. The results show that 8% of the DH for the rice protein has good solubility, emulsifying and foaming properties. With the DH increase, rice protein hydrolysis emulsification and excessive foaming characteristics were decreased in different degrees. And the amino acid compositions have no significant changes. The experimental results show that the relationship between solubility and hydrolysis in different hydrolysis conditions prove when joined with the more protease or reaction time,the distribution in the soluble protein hydrolysis has a higher proportion of the protease.And on the basis of modification by protease, the effect of TGase on rice protein of 16% DH was studied.
This paper focused on studying the skin-whitening agent from radix puerariae and its inhibitory capability against tyrosinase. The active agents were extracted from radix puerariae and the processing conditions were optimized with the orthogonal design test. After the process of separation and purifying, the skin-whitening agent was obtained, and the inhibitory effect of puerarin on tyrosinase was studied, using enzymological kinetic method.The water and ethanol extracts of radix puerariae, Lonicera japonica Thunb., Artemisia anomala S. Moore and Dispyrosl kaki Lf. were obtained by refluxing with both water and 75%(v/v)ethanol, concentration and drying, respectively. The inhibitory capability of water and 75%(v/v)ethanol extracts against tyrosinase were investigated. The results showed that extract of radix puerariae has the stronger inhibition than others.The optimum reaction conditions of skin-whitening agent’s inhibition on tyrosinase determined by the single factor experiment method were as follows: the pH value of Phosphate Buffer Solution(PBS) was 6.85, the volume of L-Tyrosine was 1.0mL, the volume of tyrosinase was 0.4mL,time in water bath before tyrosinase added was 10 minutes and reacting time was 5 minutes.The processing conditions of ethanol extract of radix puerariae were optimized with the orthogonal design test. The optimum extracting condition was obtained as the concentration of ethanol was 75%; time for refluxing was 4h, the ratio of material and solvent was l:8 and repeat the process for 2 times. The amount of flavonoid from extract of radix puerariae was investigated, results showed that the largest amount of flavonoid was13.74%.The ethanol extract was further separated with solvents of different polar such as petroleum ether, trichloromethane, ethyl acetate and n-butylalcohol and their inhibitory capability against tyrosinase were compared. It has been found that the inhibitory capability of ethyl acetate-extracted fraction against tyrosinase was the strongest. The extract of ethyl acetate was purified by silica gel column chromatography and tracked by TLC. 10 eluants were obtained and the inhibitory capability of each eluant against tyrosinase was investigated. The results showed that the inhibition of B was 65.7% and the inhibition of D was 79.2%. B and D was further purified by silica gel column chromatography and tracked by TLC. It has been found that the inhibition of B3 obtained from B was 92.3%, and the inhibition of D4 obtained from D was 98.5%.To identify the skin-whitening agent from radix puerariae, HPLC, UV and LCMS were used. It has been confirmed that daidzein and puerarin were the two main skin-whitening agents obtained from radix puerariae.The mechanism of puerarin’s inhibition on tyrosinase was studied, using enzymological kinetic method. The results showed that puerarin was a noncompetitive inhibitor proved by its Lineweaver-Burk plots.Puerarin was applied in cosmetic. The results confirmed that puerarin has skin-lightening effect after 3 months of trial by 15 people.The antimicrobial effect of radix puerariae extract and puerarin were studied. Results showed that radix puerariae extract has better antimicrobial effect than puerarin.
Succinic acid is a C4-dicarboxylic acid. As a carbon-intermediate chemical, it can be used as a precursor of numerous products, including pharmaceuticals, food additives, green solvents, and biodegradable polymers. In this work, the separation process of succinic acid using calcium succinate precipitation, acidic ion-exchange resin and anion resin adsorption methods from fermentation broth was studied. The thesis includes four parts.First, the separation and extraction of succinic acid from fermentation broth by using calcium succinate precipitation method was studied. The effects of calcification, acid-olysis, decoloration, ion-exchange purification, concentration, and crystallization on the extraction rate were investigated, and the optimum conditions are as follows: succinic acid fermentation broth was first concentrated for 1 fold, then 40% calcium chloride solution was added to the fermentation broth in 1:1.3 (total acid:calcium chloride): at 80℃for 30 min; 60% sulfuric acid was added to calcium succinate solution at 80℃for 30 min; the optimum conditions of decoloration using active carbon were: temperature 75℃, pH 2~3, adsorption time 30 min, and 0.8% and 2.5% of TX-328P activated char for corn syrups and cane molasses fermentation broth respectively; Weak basic anion resin D315 was used to remove sulfate and chloride ions with an optimal flow velocity of 1.98 h-1(3.3.mL/min), and the extraction rate was 97%. Studies showed that the succinic acid extraction rates from 1 L of corn syrups and cane molasses fermentation broth was 66.4% and 68.9%, while the purities of succinic acid in the crystals were 99.0% and 99.5%, respectively. Meanwhile, the quality of the product could meet the standard of FCC-IV (USA). Take account into the recovery of magnesium together with the acidolysis and decoloration, the succinic acid extraction rate from corn syrups fermentation broth was 69.4% and the purity was 99.4%.Second, the separation and extraction of succinic acid from fermentation broth by using acidic ion-exchange resin 732 was studied. The extraction rate of 92.3% was achieved at an optimal flow velocity of about 1.5h-1(2.5mL/min), and 0.3~0.5% and 1.0%~1.2% of TX-328P activated char were added to corn syrups and cane molasses fermentation broth, which was reduced for 0.3% and 1.3% compared with calcium succinate precipitation method In order to minimize the costs of extraction, the recovery of sodium, magnesium and potassium salt is studied in this work. The recovery rate of sodium salt is up to 94.5% when 1.5 mol/L of ammonium bicarbonate and a elution flow rate at 1 mL/min were applied. Using above technologies to the extraction of succinic acid from corn syrups and cane molasses fermentation broth, the yields of succinic acid were 86.8% and 80.2%, while the purities of succinic acid in the crystal were 92.3% and 90%, respectively.Third, the separation and extraction of succinic acid from fermentation broth by using anion-exchange resin was studied. Weak basic anion-exchange resin 330 was selected to recover succinic acid from the fermentation. The effects of pH, concentration of succinic acid and flow velocity on the exchange equilibrium between succinic acid and resin were examined. The optimal conditions for higher total exchange capacity were determined to be pH 6.0, 40 g/L of succinic acid, and 2.9 h-1 (1.6 mL/min) of flow rate. Elution experiments also demonstrated that 2 mol/L hydrochloric acid and a low flow rate of 1.8 h-1(1 mL/min) favored high elution efficiency. Under the optimal operation conditions, the recovery rate of succinic acid from fermentation broth achieved 71.4% with 95% succinic acid purity in the crystal.Fourth, cost estimation of above three extraction methods. Our comparison study showed that, the highest succinic acid yield of 86.8% was achieved using acidic ion-exchange resin. Considering the material cost and salt recovery cost among three methods, the lowest cost of 2110 yuan per ton was achieved using anion resin adsorption, which accounts for 11.7% of the market price of succinic acid. Taken together, this method for the extraction of succinic acid is promising in the future development.
Extraction, Separation, Identification and Permentry Studies on Whitening Skin Activity of Triterpenes from Surface Layer of Poria Cocos
“Hoelen”（Poria cocos（Schw.） Wolf） is a specific and tradition herb which is also edible in China.,having very remarkable biologic activities and pharmacological functions.During processing Poria cocos,the surface layer of Poria cocos was abondoned so as to lead to the great waste of resource.For enhancing the utilizing frequencies of “Hoelen” and the additive valual of its production,or studying the useful elements of Poria cocos further,In this paper,the extraction,isolation,purification and whitening skin activities,including anti- bacteria,anti-inflammatory,antioxidant and inhibiting tyrosinase activity,of triperpenes in the surface layer of Poria cocos were studied,.The results were as follows:1.Determination of the content,the optimal extraction condition and the qualitative analysis of crude triperpenes extracted from the surface layer of Poria cocos:The surface layer of Poria cocos produced in Jiuzihe village,Dabie mountain area,Hubei Province as the raw material,the content of triperpenes in it was 1.59%determined with the colorimetry of vanillic aldehyde-acetic acid-perchloric acid.The optimal extraction condition of triperpenes extracted with methnal was established.When the material was extracted with ethanol 6h at 70℃and at the ratio of liquid to material（v/w） 1:20 for twice times,the extraction rate of triperpenes was 95.2%,and the purity of sample extracted was 78.5%.The data of chemical reactions,UV spectrum,IR spectrum,HPLC spectrum and mass spectrum were shown that the extracts from surface layer of Poria cocos had varieties of triperpenes and 18 kinds of triperpenes could be identified.2.Separation,purification,preparation and identification of triperpenes extracted from surface layer of Poria cocos:The different fractions got from the crude triperpenes of surface layer of Poria cocos were preparated through the separation and purification made by column chromatography with silica gel,and identified by the methods of UV,IR, HPLC.The results were shown that three kinds of fractions were not single element but the mixture of various triperpenes having some degree of purity.3.Determination of various whitening skin activities:The anti-bacteria activity was determined by the method of growth rate,the results were shown that Escherichia coli, Staphylococcus aureus,Pseudomonas aeruginosa were all inhibited more greatly and stable by the crude triperpenes extracted from and its purified fractions;the experimental result of xylene-induced mouse auricle swelling was shown that the crude triperpenes surface layer of Poria cocos had the better anti-inflammatory activity;the better anti-oxidant activity of the crude triperpenes and its purified fractions was testified by scavenging O2·,OH-,H2O2 effectively,inhibiting red cell oxidation induced by auto or H2O2,inhibiting liver lipid peroxidation representing the formation of malondialdehyde induced by auto or Fe-H2O2,respectively;the inhibiting tyrosinase activity of crude triperpenes and its purified fractions were also shown,but it was bidirectional function and changed with the sample concentration changing.
Study on Extraction, Purification, Structural Identification and Its Bioactivities of Flavonoids in Lotus Leaf
The technologies of the extraction and purification of the total flavonoids from lotus leaf were studied in this thesis.The chemical, spectral, chromatographic and mass spectrographic analysis were used to research the structure and bioactivities of flavonoids in lotus leaf. The main results were as follows:1. Optimization for extraction process of flavonoids in lotus leavfEffects of extraction solvent,the surfactant concentration,time, temperature and solidsolvent ratio on extraction yields of flavonoids from lotus leaf were determined individually. The quadratic regression rotational combination design with three factors was used to optimize the extract process and the extraction rate of flavonoids from lotus leaf was chosen as the evaluating index. The equation was Y=67.03+2.68x1+0.16x2+2.94x3-2.06x1x2-0.43x1x3+0.41x2x3-4.74x12-4.33x22-4.93x32,After optimizing the combination different factors by computer, the results showed that the optimum extraction parameters were : temperature（74.8-6.5℃）,time（38-43min） and proportion of material and liquid（1:25-1:28）. The gain ratio was 59.5%2. Study on methods for purification of flavonoids in lotus leafFive types of macroporous resin were compared in their ability of adsorbing and desorbing flavonoids in lotus leaf. The dynamic absorbing behavior of XAD16 resin was observed. The optimum conditions were as follows: the elution solution concentration 1.1mg/mL, the flow rate of absorption solution 1BV/h, , 50% ethanol as eluent,flow rate in 2BV/h,the elution peak was symmetrical in the optimum conditions.The flavonoids in lotus leaf was further purified by recrystallization and the purity was 92%.3. Preliminary study on the structure of flavonoids in lotus leafThe structure of flavonoids in lotus leaf were characterized by UV-VIS, FT-IR,HPLC-ESI/MS,HPLC and GC respectively. The structure was estimated as Isorhamnetin-3 -O-β-D-glucoside4. Bioactivities of flavonoids in lotus leaf（1）Antioxidation activity of flavonoids in lotus leaf in vitroEffects of flavonoids in lotus leaf on removal of superoxide anion, hydroxide radical and H2O2 was determined by Pyrogallol-Luminol system,CuSO4-Phen-VC-H2O2 system and Luminol-H2O2 systems respectively. The effect of preventing DNA damage by flavonoids in lotus leaf was determined by CuSO4-Phen-VC-H2O2-DNA chemilum inescence’s system.The results showed that flavonoids in lotus leaf possessed a high scavenging potency on ROS and preventing DNA damage in different systems Effects of flavonoids in lotus leaf on antioxidation of zoogenic tissue in vitro were determined by chromatometry.The results showed that flavonoids in lotus leaf could eliminate OH effectively , inhibit lipid peroxidation induced by OH., protect the biomembrane, reduce RBC hemolysis and lighten the degree of liver mitochondria swelling. The results suggested that flavonoids in lotus leaf possessed remarkable antioxidation activities.（2） Effects of flavonoids in Lotus leaf on activities of amylase and lipase in vitroEffects of the flavonoids concentration,action time and dosage of enzyme on activities of amylase and lipase were determined by chromatometry.The results were as follows: （a）flavonoids in lotus leaf blocked the enzyme-substrate contact by modifying the emulsion of the lipid substrate, and the lipase inhibitor demonstrated uncompetitive inhibition for lipase; （b） The intensive inhibiting effect of crude flavonoids in lotus leaf on the amylase activity was higher than that of purified flavonoids.The results suggested that inhibiting effect of flavonoids in lotus leaf on amylase activity might be synergistic effect between flavonoids and other compounds in lotus leaf.