Marine organisms constitute unlimited resource of bioactive substances due to their high biodiversity and represent a valuable source of new compounds. This study optimized the alkali-extraction conditions and antioxi...Marine organisms constitute unlimited resource of bioactive substances due to their high biodiversity and represent a valuable source of new compounds. This study optimized the alkali-extraction conditions and antioxidant activities of soluble polysaccharides from the body wall of Sipunculus nudus. The effects of solid-liquid ratio, extraction duration, extraction temperature, and alkali concentration on the yield of S. nudus polysaccharides(SNP) were examined, according to which the optimal combination of extraction parameters was obtained by an orthogonal test. The relative influencing importance of different extraction parameters on the yield of SNP followed the order as solid-liquid ratio > extraction temperature > alkali concentration > extraction duration. The highest extraction yield, 1.98%, was achieved under an optimal extraction condition: temperature 60℃, solid-liquid ratio 1:6 g mL^(-1), duration 5 h, and alkali(Na OH) mass fraction 6%. The in vitro antioxidant activities examination showed that extracted SNP under this optimized condition had strong power in reducing certain hydroxyl and superoxide radical scavenging abilities. The promising results showed that extracted SNP could be a potent natural antioxidant.展开更多
[Objectives]This study was conducted to optimize the extraction process of Sipunculus nudus polysaccharide and study the antioxidant activity of S. nudus polysaccharide. [Methods] S. nudus polysaccharide was extracted...[Objectives]This study was conducted to optimize the extraction process of Sipunculus nudus polysaccharide and study the antioxidant activity of S. nudus polysaccharide. [Methods] S. nudus polysaccharide was extracted by ultrasonic microwave assisted method,during which univariate factors including solidliquid ratio,time,temperature,ultrasonic power,microwave power were investigated,to select optimal extracting conditions,which were also verified by an response surface optimization experiment( an four-factor three-level test); and the antioxidant activity of S. nudus polysaccharide was studied by determining its DPPH radical scavenging capacity. [Results]Through univariate factor investigation and response surface optimization test,it was found that the response surface results were consistent with univariate results. The optimized conditions were as follows: solid-liquid ratio at 1∶ 15,ultrasonic temperature at 60 ℃,ultrasonic power of 360 W and microwave power of 200 W,and the predicted polysaccharide extracting amount was 4. 35 mg/g. Under the optimized extracting conditions,the average extracting amount of S. nudus polysaccharide was 4. 38 mg/g,which is close to the theoretical predicted value( 4. 35 mg/g). And the results of this study also showed that different concentrations of polysaccharide solutions have different scavenging effects on DPPH free radical. At the polysaccharide concentration of0. 16 mg/ml,the maximum value of DPPH radical scavenging rate was 7. 22%,indicating that polysaccharide has certain antioxidant capacity. [Conclusions]This method is a new trial with satisfactory results.展开更多
[Objectives] This study was conducted to optimize the extraction process of Sipunculus nudus polysaccharide. [Methods]S. nudus polysaccharide was extracted by ultrasonic water extraction,with the marine S. nudus as a ...[Objectives] This study was conducted to optimize the extraction process of Sipunculus nudus polysaccharide. [Methods]S. nudus polysaccharide was extracted by ultrasonic water extraction,with the marine S. nudus as a raw material from Sanya City,Hainan Province,by single factor variable method,to find the optimal extraction conditions including ultrasonic power,solid-liquid ratio,ultrasonic extraction temperature,ultrasonic extraction time,ultrasonic extraction times and lye concentration. The absorbance of the polysaccharide was determined by an ultraviolet spectrophotometer,and polysaccharide yield were calculated. The antioxidant activity of scavenging hydroxyl and DPPH radicals was measured at different concentrations. [Results]The optimal extraction conditions for S. nudus polysaccharide were as follows: solid-liquid ratio at 1∶11 mg/ml,extraction temperature at 60 ℃,three times of ultrasonic extraction,ultrasonic power of 960 W,extraction time of 1. 5 h,and lye concentration of 5%,under which the polysaccharide yield was 3. 21%. The scavenging rates of hydroxyl radical and DPPH radical were 12. 58% at the concentration of 0. 20 mg/ml. Moreover,the scavenging rates increased significantly with the increase of concentration. [Conclusions] This method is a new trial with satisfactory results.展开更多
[Objective] This study was conducted to investigate the effects of dietary carbohydrate-lipid( C / L) ratios on growth performance,body composition and digestive enzyme activities of juvenile peanut worm. [Methods]Juv...[Objective] This study was conducted to investigate the effects of dietary carbohydrate-lipid( C / L) ratios on growth performance,body composition and digestive enzyme activities of juvenile peanut worm. [Methods]Juvenile peanut worm with average body weight of( 16. 77 ± 0. 40) mg were fed with five isonitrogenous and isoenergetic diets formulated to contain different carbohydrate / lipid( C / L) ratios( 0. 68,1. 02,1. 62,2. 61 or 4. 35) for 8 weeks. [Results] The dietary C / L ratios had no significant effects on survival of juvenile peanut worm( P 】 0. 05). With the increasing of dietary C / L ratios,weight growth rate( WGR)and specific growth rate( SGR) increased when dietary C / L ratios were between 0. 68 and 2. 61,and then decreased significantly with dietary C / L ratio further increased. When the dietary C / L ratio was 2. 61( carbohydrate level was 20. 64%,lipid level was 7. 92%) both WGR and SGR produced the maximum value,they were 451. 78 ± 16. 85% and 3. 41 ± 0. 06 % / d,respectively. The dietary C / L ratios had significant effects on body moisture,body protein content and body lipid content( P 【 0. 05),but no significant effects on body ash content of juvenile peanut worm( P 】 0. 05). Different C / L ratios had significant effects on amylase activity and lipases activity of juvenile peanut worm( P 【 0. 05),but no significant effects on protease activity( P 】 0. 05). [Conclusion]The regression model analysis showed that the most suitable dietary C / L ratio which can make juvenile peanut worm acquire the best weight growth rate is 2. 42.展开更多
In the study,glucose,sucrose,dextrin,tapioca starch,potato starch,corn starch and gelatinized corn starch were selected to make the diets with same nitrogen and lipid,and Juvenile peanut worms( Sipunculus nudus) were ...In the study,glucose,sucrose,dextrin,tapioca starch,potato starch,corn starch and gelatinized corn starch were selected to make the diets with same nitrogen and lipid,and Juvenile peanut worms( Sipunculus nudus) were fed with the diets came from different carbohydrate sources,effects of diets with different carbohydrate sources on daily weight gain and digestive enzyme activities of S. nudus were studied. Results showed that diets with different carbohydrate sources had significant influences on daily weight gain and digestive enzyme activities of S. nudus( P < 0. 05). Daily weight gain in gelatinized corn starch group was significantly higher than that in other groups( P < 0. 05); daily weight gain in glucose group was significantly lower than that in other groups( P < 0. 05); daily weight gain in the three ungelatinized starch groups was significantly higher than that in glucose,sucrose and dextrin groups( P < 0. 05). Analysis of digestive enzyme activities showed that dietary carbohydrate sources had significant influences on digestive enzyme activities of S. nudus( P < 0. 05). Protease activities and amylase activities of S. nudus in sucrose group were the highest,which were significantly higher than that in the other groups( P < 0. 05); lipase activities of S. nudus in glucose group were the lowest,which were significantly lower than that in other groups( P < 0. 05). In conclusion,growth-promoting effects of macromolecules carbohydrates( starch) were better than that of disaccharide( sucrose) and monosaccharide( glucose),which of gelatinized starch were better than that of ungelatinized starch.展开更多
[Objectives] This study was conducted to optimize experimental conditions for extraction of polysaccharides from Sipunculus nudus.[Methods]With the Sipunculus nudus from Sanya as the experimental material,S.nudus poly...[Objectives] This study was conducted to optimize experimental conditions for extraction of polysaccharides from Sipunculus nudus.[Methods]With the Sipunculus nudus from Sanya as the experimental material,S.nudus polysaccharide was extracted by ultrasonic microwave assisted method,during which univariate factors including solid-liquid ratio,time,temperature,ultrasonic power,microwave power were investigated,to select optimal extracting conditions,which were also demonstrated and optimized by variance and response surface analysis.The optimized conditions were adopted to carry out a test,in which the absorbance of S.nudus polysaccharide was measured with an ultraviolet and visible spectrophotometer,followed by the calculation of the extracting amount of polysaccharide,and precision test and recovery test were also carried out to verify the experimental method.[Results]The standard solutions were determined at the maximum absorption wavelength of 486 nm,and the regression equation was A = 0.2677 C + 0.001 8,R^2= 0.999 8.Solid-liquid ratio,time,temperature,ultrasonic power and microwave power were investigated by univariate analysis and then optimized by response surface method as follows: solid-liquid ratio at 1:20( g/ml),time of 35 min,temperature at 50 ℃,ultrasonic power at 420 W and microwave power at 300 W,under which the measured extracting amount of S.nudus polysaccharide was1.37 mg/g.The RSD was 0.985% in precision experiment.In the repeatability test,the extracting amounts of polysaccharide were 1.41,1.43 and 1.38 mg/g for three parallel tests,respectively,with a RSD of 1.140%.The recovery test obtained following results: for group a( added with glucose standard) : the recovery of S.nudus polysaccharide was in the range of 100.3%-101.4%,RSD = 0.03%; and for group b( not added with glucose standard) : the recovery of S.nudus polysaccharide was in the range of 99.7%-100.3%,RSD = 0.02%.[Conclusions]The research method is stable and reliable.This study provides data basis and reference for follow-up study on S.nudus.展开更多
基金financially supported by the Nationa Natural Science Foundation of China (Project Nos 31160532 & 31402304)the Scientific Research and Technology Development Program of Guangxi (Projec Nos. 11107011-6, 1346011-12, 14121006-2-12 & 141250 08-2-20)
文摘Marine organisms constitute unlimited resource of bioactive substances due to their high biodiversity and represent a valuable source of new compounds. This study optimized the alkali-extraction conditions and antioxidant activities of soluble polysaccharides from the body wall of Sipunculus nudus. The effects of solid-liquid ratio, extraction duration, extraction temperature, and alkali concentration on the yield of S. nudus polysaccharides(SNP) were examined, according to which the optimal combination of extraction parameters was obtained by an orthogonal test. The relative influencing importance of different extraction parameters on the yield of SNP followed the order as solid-liquid ratio > extraction temperature > alkali concentration > extraction duration. The highest extraction yield, 1.98%, was achieved under an optimal extraction condition: temperature 60℃, solid-liquid ratio 1:6 g mL^(-1), duration 5 h, and alkali(Na OH) mass fraction 6%. The in vitro antioxidant activities examination showed that extracted SNP under this optimized condition had strong power in reducing certain hydroxyl and superoxide radical scavenging abilities. The promising results showed that extracted SNP could be a potent natural antioxidant.
基金Supported by National Natural Science Foundation of Hainan Province(217157)2017 Provincial College Students' Innovation and Entrepreneurship Training Program(201711100005)2018 Provincial Key Discipline (Thalassochemistry) Construction Fund
文摘[Objectives]This study was conducted to optimize the extraction process of Sipunculus nudus polysaccharide and study the antioxidant activity of S. nudus polysaccharide. [Methods] S. nudus polysaccharide was extracted by ultrasonic microwave assisted method,during which univariate factors including solidliquid ratio,time,temperature,ultrasonic power,microwave power were investigated,to select optimal extracting conditions,which were also verified by an response surface optimization experiment( an four-factor three-level test); and the antioxidant activity of S. nudus polysaccharide was studied by determining its DPPH radical scavenging capacity. [Results]Through univariate factor investigation and response surface optimization test,it was found that the response surface results were consistent with univariate results. The optimized conditions were as follows: solid-liquid ratio at 1∶ 15,ultrasonic temperature at 60 ℃,ultrasonic power of 360 W and microwave power of 200 W,and the predicted polysaccharide extracting amount was 4. 35 mg/g. Under the optimized extracting conditions,the average extracting amount of S. nudus polysaccharide was 4. 38 mg/g,which is close to the theoretical predicted value( 4. 35 mg/g). And the results of this study also showed that different concentrations of polysaccharide solutions have different scavenging effects on DPPH free radical. At the polysaccharide concentration of0. 16 mg/ml,the maximum value of DPPH radical scavenging rate was 7. 22%,indicating that polysaccharide has certain antioxidant capacity. [Conclusions]This method is a new trial with satisfactory results.
基金Supported by National Natural Science Foundation of Hainan Province(217157)Fund for Construction of Provincial Key Discipline(thalassochemistry)in 2017
文摘[Objectives] This study was conducted to optimize the extraction process of Sipunculus nudus polysaccharide. [Methods]S. nudus polysaccharide was extracted by ultrasonic water extraction,with the marine S. nudus as a raw material from Sanya City,Hainan Province,by single factor variable method,to find the optimal extraction conditions including ultrasonic power,solid-liquid ratio,ultrasonic extraction temperature,ultrasonic extraction time,ultrasonic extraction times and lye concentration. The absorbance of the polysaccharide was determined by an ultraviolet spectrophotometer,and polysaccharide yield were calculated. The antioxidant activity of scavenging hydroxyl and DPPH radicals was measured at different concentrations. [Results]The optimal extraction conditions for S. nudus polysaccharide were as follows: solid-liquid ratio at 1∶11 mg/ml,extraction temperature at 60 ℃,three times of ultrasonic extraction,ultrasonic power of 960 W,extraction time of 1. 5 h,and lye concentration of 5%,under which the polysaccharide yield was 3. 21%. The scavenging rates of hydroxyl radical and DPPH radical were 12. 58% at the concentration of 0. 20 mg/ml. Moreover,the scavenging rates increased significantly with the increase of concentration. [Conclusions] This method is a new trial with satisfactory results.
基金Supported by Natural Science Foundation of Guangxi Zhuang Autonomous Region(2011GXNSFB018057)Science and Technology Development Program of Guangxi Zhuang Autonomous Region(11107011-6+3 种基金1346011-1214125008-2-20)Science and Technology Development Program of Beihai City(201153009)Special Fund for Innovation Project of Guangxi Zhuang Autonomous Region(2012cxjh A014)
文摘[Objective] This study was conducted to investigate the effects of dietary carbohydrate-lipid( C / L) ratios on growth performance,body composition and digestive enzyme activities of juvenile peanut worm. [Methods]Juvenile peanut worm with average body weight of( 16. 77 ± 0. 40) mg were fed with five isonitrogenous and isoenergetic diets formulated to contain different carbohydrate / lipid( C / L) ratios( 0. 68,1. 02,1. 62,2. 61 or 4. 35) for 8 weeks. [Results] The dietary C / L ratios had no significant effects on survival of juvenile peanut worm( P 】 0. 05). With the increasing of dietary C / L ratios,weight growth rate( WGR)and specific growth rate( SGR) increased when dietary C / L ratios were between 0. 68 and 2. 61,and then decreased significantly with dietary C / L ratio further increased. When the dietary C / L ratio was 2. 61( carbohydrate level was 20. 64%,lipid level was 7. 92%) both WGR and SGR produced the maximum value,they were 451. 78 ± 16. 85% and 3. 41 ± 0. 06 % / d,respectively. The dietary C / L ratios had significant effects on body moisture,body protein content and body lipid content( P 【 0. 05),but no significant effects on body ash content of juvenile peanut worm( P 】 0. 05). Different C / L ratios had significant effects on amylase activity and lipases activity of juvenile peanut worm( P 【 0. 05),but no significant effects on protease activity( P 】 0. 05). [Conclusion]The regression model analysis showed that the most suitable dietary C / L ratio which can make juvenile peanut worm acquire the best weight growth rate is 2. 42.
基金Supported by National Natural Science Foundation of China(Project No.31160532&31402304)Guangxi Natural Science Foundation(Project No.2015GXNSFBB139005)Scientific Research and Technology Development Program of Guangxi(Project No.1346011-12&14125008-2-20)
文摘In the study,glucose,sucrose,dextrin,tapioca starch,potato starch,corn starch and gelatinized corn starch were selected to make the diets with same nitrogen and lipid,and Juvenile peanut worms( Sipunculus nudus) were fed with the diets came from different carbohydrate sources,effects of diets with different carbohydrate sources on daily weight gain and digestive enzyme activities of S. nudus were studied. Results showed that diets with different carbohydrate sources had significant influences on daily weight gain and digestive enzyme activities of S. nudus( P < 0. 05). Daily weight gain in gelatinized corn starch group was significantly higher than that in other groups( P < 0. 05); daily weight gain in glucose group was significantly lower than that in other groups( P < 0. 05); daily weight gain in the three ungelatinized starch groups was significantly higher than that in glucose,sucrose and dextrin groups( P < 0. 05). Analysis of digestive enzyme activities showed that dietary carbohydrate sources had significant influences on digestive enzyme activities of S. nudus( P < 0. 05). Protease activities and amylase activities of S. nudus in sucrose group were the highest,which were significantly higher than that in the other groups( P < 0. 05); lipase activities of S. nudus in glucose group were the lowest,which were significantly lower than that in other groups( P < 0. 05). In conclusion,growth-promoting effects of macromolecules carbohydrates( starch) were better than that of disaccharide( sucrose) and monosaccharide( glucose),which of gelatinized starch were better than that of ungelatinized starch.
基金Supported by National Natural Science Foundation of Hainan Province(217157)2017 Provincial College Students'Innovation and Entrepreneurship Training Program(201711100005)2018 Provincial Key Discipline(Thalassochemistry)Construction Fund
文摘[Objectives] This study was conducted to optimize experimental conditions for extraction of polysaccharides from Sipunculus nudus.[Methods]With the Sipunculus nudus from Sanya as the experimental material,S.nudus polysaccharide was extracted by ultrasonic microwave assisted method,during which univariate factors including solid-liquid ratio,time,temperature,ultrasonic power,microwave power were investigated,to select optimal extracting conditions,which were also demonstrated and optimized by variance and response surface analysis.The optimized conditions were adopted to carry out a test,in which the absorbance of S.nudus polysaccharide was measured with an ultraviolet and visible spectrophotometer,followed by the calculation of the extracting amount of polysaccharide,and precision test and recovery test were also carried out to verify the experimental method.[Results]The standard solutions were determined at the maximum absorption wavelength of 486 nm,and the regression equation was A = 0.2677 C + 0.001 8,R^2= 0.999 8.Solid-liquid ratio,time,temperature,ultrasonic power and microwave power were investigated by univariate analysis and then optimized by response surface method as follows: solid-liquid ratio at 1:20( g/ml),time of 35 min,temperature at 50 ℃,ultrasonic power at 420 W and microwave power at 300 W,under which the measured extracting amount of S.nudus polysaccharide was1.37 mg/g.The RSD was 0.985% in precision experiment.In the repeatability test,the extracting amounts of polysaccharide were 1.41,1.43 and 1.38 mg/g for three parallel tests,respectively,with a RSD of 1.140%.The recovery test obtained following results: for group a( added with glucose standard) : the recovery of S.nudus polysaccharide was in the range of 100.3%-101.4%,RSD = 0.03%; and for group b( not added with glucose standard) : the recovery of S.nudus polysaccharide was in the range of 99.7%-100.3%,RSD = 0.02%.[Conclusions]The research method is stable and reliable.This study provides data basis and reference for follow-up study on S.nudus.