Dissertation > Excellent graduate degree dissertation topics show

Study on the Extraction Technology, Antioxidation and Antibacterial Activity of Lotus-seed Polyphenols

Author: HuangSuYing
Tutor: ZhengBaoDong
School: Fujian Agriculture and Forestry University
Course: Of Food Science
Keywords: lotus seed polyphenols microwave-assisted extraction anti-oxidation antibacterial activity HPLC
CLC: R151
Type: Master's thesis
Year: 2010
Downloads: 318
Quote: 4
Read: Download Dissertation

Abstract


Lotus seed (Nelumbo nucifera Gaertn) belongs to Basidiomycotina. It is a kind of precious fungus used for food and medicine, which has rich nutrition and special health value. The extraction technology, the anti-oxidantive effect and the antibacterial activity of lotus seed polyphenols were studied in this paper. And then the active components of lotus seed polyphenols were analyzed by HPLC. In order, an important recommedation for developing deep-processing products of lotus seed were offered.(1) The extraction technology of polyphenols from dried lotus seed was studied in this experiment. Different factors were considered, such as the kinds of the solvent, the concentration of solvent, extractive temperature, ratio of material to liquid, extractive time and extractive frequency. Based on the single factor tests, the optimum extraction technology was determined through orthogonal experiments: the ethanol concentration was 90%, the ratio of material to liquid was 1:15, the extraction time was 1.5 hours, the extractive temperature was 60℃, and the extractive frequency was 3 times. Under this condition, the extraction rate of lotus seed would be 7.58 mg/g. Ultrasonic effect on the extraction rate of lotus seed polyphenols were studied, in addition, the result shown ultrasonic effect could improve the extraction rate of lotus seed polyphenols.(2) The extraction of lotus seed polyphenols by microwave-assisted extraction technique were studied in this experiment. Different factors were considered, such as ethanol concentration, microwave power, treatment time, ratio of material to liquid, and so on. Based on the single factor tests, the optimum extraction technology was determined through orthogonal experiments: ethanol concentration was 90 %, ratio of material to liquid was 1:10, the power of the microwave radiation was 300 W, extraction time was 35 s, the frequency of microwave extraction was three times. Under such conditions, the extraction rate of lotus seed was 7.74 mg·g-1.(3) Using tea polyphenol(TP)and Vc as comparisons, the effect on scavenging·OH and·O2- of lotus seed polyphenols (LSP) was studied by using fenton reaction and pyrogallol autoxidation methods respectively. The results showed that lotus seed polyphenols had certain ability to scavenge·OH and·O2- with the various concentrations in the study. When the concentrations were same, lotus seed polyphenols have stronger ability to scavenge·O2- than tea polyphenol and Vc, but have weaker ability to scavenge·OH. The oil anti-oxidation of lotus seed polyphenols was studied, In addition, the result shown that lotus seed polyphenols have certain ability of anti-oxidation to oil.(4) Using tea polypheno(lTP)as the comparison, The antibacterial action of lotus seed polyphenols was studied. The result shown that lotus seed polyphenols have a notable inhibiting microorganism activity against Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Bacillus subtilis and listeria spp, but it have no antibacterial activity against Trichodenna viride and Stachybotrys Chartarum. Meanwhile, changing temperature within limits could have little affect the antibacterial activity of lotus seed polyphenols, and the antibacterial effect of lotus seed polyphenols was not obviously changed in the pH5-8. In addition, the MIC for five kinds of bacterias were as follow: Staphylococcus aureus, 0.3 mg/mL; Bacillus subtilis, 0.4 mg/mL; listeria spp, 0.4 mg/mL; Escherichia coli, 0.8 mg/mL and Salmonella typhimurium, 0.8 mg/mL.(5) The determination of the components of lotus seed polyphenols was studied by HPLC. The results showed that 4 kinds of polyphenol acids were determined in the lotus seed, including chlorogenic acid standard. The content of chlorogenic acid was 0.8 mg/100g. Flavonoids were determined in the lotus seed, including rutin standard. The content of rutin was 1.2 mg/100g.

Related Dissertations

  1. Research on the Effects of Protection and Renovation of Apple Polyphenols on UVB-Induced HepG2 Cell Injury,S661.1
  2. Studies on Extraction, Isolation, Purification and Antioxidation Activity of Flavonoids from the Fruits of Avicennia Marina,S793.9
  3. Research of Glycosaminoglycan from Perna Virids Effect on Blood Lipid,R285.5
  4. Study on the Syntheses and Antibacterial Acticity of Metal Organic Complexes Built from Three Carboxylate Ligands,O621.13
  5. Study on the Pharmacokinetics of Xiaoaiping and Chlorogenic Acid in Rats and the Quality Standard of Xiaoaiping Preparations,R285
  6. Study on Phylogenetic Diversity and Bioactivity of Symbiotic Fungi of Coral,R284
  7. The Study on Anti Tumor and Anti-oxidation Activities in Vitro of Extracts from Oxalis Corniculata L,R285
  8. Isolation Entophytes and Study on the Fermentation of Bacillus Subtilis tiD7 from Rehmannia,TQ461
  9. Prokaryotic Expression and Purification of Human Beta-Defensin-9,Q78
  10. Research on Biological Modification and Protection Activity of R-Phycoerythin from Porphyra Yezoensis,TS201.21
  11. Study on Extraction,purification and Antioxidant Activity of Wheat Germ Polysaccharides,TS210.1
  12. Development of Detection Methods of Effective Biological Components from Tea by High Performance Liquid Chromatography and Their Applications in the Analysis of Fenghuang Oolong Tea,TS272.7
  13. Studies on the Formation and Control of Volatile N-Nitrosamines in Dry-Cured Meat,TS251.51
  14. Studies on the Residues of Bromoxynil and Mesotrione in Maize and Soil,S481.8
  15. Cucumber Growth Promotion and Wilt Disease Suppression of Bacillus Subtilis SQR9 and Their Mechanisms,S436.421
  16. Production of Monoclonal Antibodies Against Thiabendazole and Development of Heterologos Elisa,S482.2
  17. The Yunnan ten kinds of pepper antioxidant and antibacterial activity of the research,S641.3
  18. Determination Method and Extraction Purification of Terpenoid Indole Alkaloids in Catharanthus Roseus,R284
  19. The Anti-oxidation Activity and Microencapsulation of the Extract from Eucommia Ulmoide Oliver Leaves,R285.5
  20. Study on Synthetic of BINOL, Amino Acid and Derivatives Molecularly Imprinted Polymers and Their Application in the Chiral Resolution,O631.3
  21. Detecting Melamine in Feed by High-Performance Liquid Chromatography,S816.17

CLC: > Medicine, health > Preventive Medicine,Health > Nutrition, hygiene,food hygiene > Nutrition
© 2012 www.DissertationTopic.Net  Mobile