TAILIEUCHUNG - Effect of extraction conditions on the antioxidant activity of Vernonia amygdalina Del. (Asteraceae)

In this study, the effect of extraction conditions on the antioxidant activity of Vernonia amygdalina Del. (Asteraceae) was evaluated by Response surface methodology and central composite design (RSM-CCD) to predict the content of phenolic compounds with maximum antioxidant activity. | Effect of extraction conditions on the antioxidant activity of Vernonia amygdalina Del. (Asteraceae) TẠP CHÍ PHÁT TRIỂN KHOA HỌC VÀ CÔNG NGHỆ - 37 KỸ THUẬT & CÔNG NGHỆ, TẬP 1, SỐ 3, 2018 Effect of extraction conditions on the antioxidant activity of Vernonia amygdalina Del. (Asteraceae) Dinh Chung Duong*, Ngoc Yen Nguyen Thi, Hung Lam Hoa are evidences that the regression model can Abstract—In this study, the effect of represent the experimental data well. HPLC extraction conditions on the antioxidant activity showed that leaves contain at least six of Vernonia amygdalina Del. (Asteraceae) was flavonoids, two of which are apigenin and evaluated by Response surface methodology luteolin. The flavonoids apigenin and luteolin and central composite design (RSM-CCD) to were identified in the extract from Vernonia predict the content of phenolic compounds with amygdalina with high levels of apigenin ( maximum antioxidant activity. Total phenol mg/g dw), luteolin ( mg/g dw). and flavonoid contents were determined by Keywords—Vernonia amygdalina Del., spectrophotometry method, especially the extraction conditions, polyphenol, antioxidant flavonoid content was identified by HPLC-DAD activity, oxidative stress. system. The antioxidant activity was estimated by the DPPH and the FRAP method. Results 1 INTRODUCTION showed that extracting time, extracting temperature and solvent-to-material ratio had a significant effect on phenolic content (p < F ree radicals play important roles and necessary for life. It was produced continuously in all cells as part of a normal cellular function. Free ). The interactions between the three radicals and oxidants contain both toxic and factors were also found to be significant at beneficial compounds. Oxidative stress, arising as level of probability. After re-estimating a result of an imbalance between free radical predicted variables on the experiment, we production

• Cơ khí - Chế tạo máy
• The antioxidant activity of Vernonia amygdalina Del
• Central composite design
• Maximum antioxidant activity
• The content of phenolic compounds
• Response surface methodology
• Alcoholic fermentation of custard apple juice
• Saccharomyces cerevisiae using response surface methodology
• The experimental values
• Optimization of conditions for extraction of collagen
• The skin of Pangasius hypophthalmus by response surface methodology
• Acetic acid concentration
• Modeling of laser direct structuring process
• Optimization of laser direct structuring process
• Artificial neural network and response surface methodology
• The MID products
• Response surface methodology for evaluating material removal
• Rate die sinking EDM roughing using copper electrode
• Rate die sinking EDM roughing
• Term of MRR
• Lactobacillus gasseri
• Lactobacillus Gasseri NBL 18
• Bacteriocin production
• Low calorie
• Hemidesmus indicus
• Bougainvillea glabra
• Response surface methodology (RSM)
• Box Behnken
• Fe (III) citrate
• Saccharomyces pastorianus
• Culture conditions of iron enriched biomass
• Central composite rotatable design
• Custard apple seed flour
• Protein isolate preparation
• Response surface methodology for optimization
• Vietnam Journal of Science and Technology
• Optimization of copper leaching from waste PCBs
• The correlation coefficient
• Optimization of scco2
• Supercritical carbon dioxide extraction
• Materials and methods
• Extraction of rambutan seed oil
• Using response surface methodology
• Invert syrup
• Citric acid
• Blending apple (Malus × domestica)
• Optimization of lactobacillus casei
• Inulin levels in the preparation
• Preparation of synbiotic
• Journal of Science and Technology
• Surface methodology approach
• The potassium hydroxide
• The response surface methodology
• The adsorption parameters
• The application of response surface methodology
• Predicting and optimizing surface roughness
• Cutting forces in hard turning by PVD coated insert
• PVD coated insert
• Coated ceramic insert
• Cutting forces according
• Modelling of tool wear
• Analysis of tool wear
• Surface roughness in hard turning of AISI D2 steel
• The analysis of variance
• Medium optimization
• Cunninghamella sp 2A1
• Response surface
• Production of biomass
• Escherichia coli BL21(DE3)
• L asparaginase
• MALDI TOF
• Escherichia coli
• The ultrasound assisted flavonoid rich extraction of fish mint
• Flavonoid rich extraction
• Methodology central composite design
• Flavonoid rich content
• Multi regression prediction model for surface roughness
• Multi regression prediction model for tool wear
• Multi regression prediction model
• Turning novel aluminum alloy (LM6)/fly ash composite
• Response surface and central composite design methodology
• Alkali activated slag
• Fly ash
• Fly ash based geopolymer activated
• Sodium hydroxide solution
• Vegetable oil
• Peroxide value
• Free fatty acids
• Oil against oxidation
• Optimization of ScSO2 extraction
• Seed of rambutan
• The canned fruit industry
• Supercritical carbon dioxide
• Mathematical models
• Pouzolzia zeylanica
• Spray drying
• Optimize additional carrier
• Possess antioxidant
• Nuclear engineering and technology
• Fragility assessment for electric cabinet in nuclear power plant
• The fragility function
• The variability of risk assessment
• Obidoxime chloride
• Molar ratio
• Enzyme’s inhibition