The response surface methodology(RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides(c FCSP) from Sargassum fusiforme. The central composit...The response surface methodology(RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides(c FCSP) from Sargassum fusiforme. The central composite design(CCD) was used with four variables, five levels, and four responses. The four variables were p H value of hydrochloric acid solution, extraction temperature(℃), ratio of liquid to raw material(m L g^(-1)), and extraction time(h), respectively. Chemical and bioassay indices were used in combination as the response parameters, which included the yield of c FCSP, fucose content, proliferation rate of spleen cells, and lipopolysaccharide-induced proliferation of splenocytes. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis, and examined using the appropriate statistical methods. The best extraction conditions were as follows: the p H value of hydrochloric acid solution was 3.50; the extraction temperature was 100℃; the ratio of liquid to raw material was 15.00 m L g^(-1) and the extraction time was 2.50 h. The experimental yield was close to the predicted from the model. The extract could promote spleen lymphocyte proliferation, especially the lipopolysaccharide-induced lymphocyte proliferation in vitro, which suggested that its immunomodulatory effect on B lymphocytes. Therefore, c FCSP extracted from S. fusiforme could be utilized as an immunostimulant in functional foods and pharmaceutical industry in future.展开更多
Chemical enhanced oil recovery(cEOR)remains one of the most potent tertiary recovery techniques.However,it is expensive and rarely environmentally friendly.Bio-based amphiphilic polymers have been suggested as an alte...Chemical enhanced oil recovery(cEOR)remains one of the most potent tertiary recovery techniques.However,it is expensive and rarely environmentally friendly.Bio-based amphiphilic polymers have been suggested as an alternative to eradicating the challenges of conventional cEOR because of cost-effectiveness,and sustainability.Unfortunately,few in-depth studies exist in the literature to investigate the prospects of these materials.A new family of amphiphilic polysaccharides was synthesized by hydrophobic modification of cellulose sulphate,and the EOR functionalities were tested.The novel biopolymers exhibited the ability to alter rock wetting properties.In terms of recovery,one of the variants of the synthesized bio amphiphilic polymer(D-I)was able to reduce residual oil saturation to 12%at harsh conditions of 60,000 ppm salinity at 75℃.Micromodel visual analysis revealed that the performance of the novel materials was due to the combination of mobility control,IFT lowering and emulsification,wettability alteration,and viscoelasticity.With a performance commensurate to that of a commercial hydrophobically modified polymer,it can be said that the novel amphiphilic polysaccharides can stand as a viable cEOR agent for oilfield applications.展开更多
基金supported by the National High Technology Research and Development Program of China (863 Program) (2013AA093003)
文摘The response surface methodology(RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides(c FCSP) from Sargassum fusiforme. The central composite design(CCD) was used with four variables, five levels, and four responses. The four variables were p H value of hydrochloric acid solution, extraction temperature(℃), ratio of liquid to raw material(m L g^(-1)), and extraction time(h), respectively. Chemical and bioassay indices were used in combination as the response parameters, which included the yield of c FCSP, fucose content, proliferation rate of spleen cells, and lipopolysaccharide-induced proliferation of splenocytes. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis, and examined using the appropriate statistical methods. The best extraction conditions were as follows: the p H value of hydrochloric acid solution was 3.50; the extraction temperature was 100℃; the ratio of liquid to raw material was 15.00 m L g^(-1) and the extraction time was 2.50 h. The experimental yield was close to the predicted from the model. The extract could promote spleen lymphocyte proliferation, especially the lipopolysaccharide-induced lymphocyte proliferation in vitro, which suggested that its immunomodulatory effect on B lymphocytes. Therefore, c FCSP extracted from S. fusiforme could be utilized as an immunostimulant in functional foods and pharmaceutical industry in future.
文摘Chemical enhanced oil recovery(cEOR)remains one of the most potent tertiary recovery techniques.However,it is expensive and rarely environmentally friendly.Bio-based amphiphilic polymers have been suggested as an alternative to eradicating the challenges of conventional cEOR because of cost-effectiveness,and sustainability.Unfortunately,few in-depth studies exist in the literature to investigate the prospects of these materials.A new family of amphiphilic polysaccharides was synthesized by hydrophobic modification of cellulose sulphate,and the EOR functionalities were tested.The novel biopolymers exhibited the ability to alter rock wetting properties.In terms of recovery,one of the variants of the synthesized bio amphiphilic polymer(D-I)was able to reduce residual oil saturation to 12%at harsh conditions of 60,000 ppm salinity at 75℃.Micromodel visual analysis revealed that the performance of the novel materials was due to the combination of mobility control,IFT lowering and emulsification,wettability alteration,and viscoelasticity.With a performance commensurate to that of a commercial hydrophobically modified polymer,it can be said that the novel amphiphilic polysaccharides can stand as a viable cEOR agent for oilfield applications.
