Fucoxanthin was extracted from the intact rhizoid of Laminariajaponica Aresch with dimethylsulfoxide (DMSO), and then recovered from the DMSO extract by partitioning into ethyl acetate and subse-quent evaporation. Som...Fucoxanthin was extracted from the intact rhizoid of Laminariajaponica Aresch with dimethylsulfoxide (DMSO), and then recovered from the DMSO extract by partitioning into ethyl acetate and subse-quent evaporation. Some isolation conditions such as solvent volume and extraction time were screened.The quantity and quality of the extracted fucoxanthin were determined by spectral analysis (absorptionspectra and fluorescence emission spectra). The results indicated that: (1) the average total content offucoxanthin was 122.1 μg in 1 g of fresh L. japonica rhizoid; (2) in comparison with the widely used organicsolvent, acetone, DMSO was much more effective for the extraction of fucoxanthin; (3) both DMSO volumeand extraction time influenced extraction efficiency such as the recovery rate and purity of fucoxanthin (1 gpurity 0.63); (4) when (NH4)2SO4 concentration was in the range of 0.5-1.0 mol/L, the pigments rapidly andentirely moved from DMSO into the ethyl acetate phase; (5) the ethyl acetate and DMSO were recycledusing a rotary evaporator.展开更多
本实验以金黄色葡萄球菌(St aphyl occoccus aureaus Rosenbach)、大肠埃希菌(Escheri-chi a col i)2种需氧型细菌作为供试细菌,用圆形纸片法对羊栖菜和海带的无菌水、乙醚和乙醇提取物进行抑菌试验。结果表明:采用水提法、95%乙醇浸提...本实验以金黄色葡萄球菌(St aphyl occoccus aureaus Rosenbach)、大肠埃希菌(Escheri-chi a col i)2种需氧型细菌作为供试细菌,用圆形纸片法对羊栖菜和海带的无菌水、乙醚和乙醇提取物进行抑菌试验。结果表明:采用水提法、95%乙醇浸提取法和乙醚索氏提取法均能从羊栖菜和海带中提取出活性物质,提取回收率依次为水提法>乙醇提法>乙醚提法;比较对羊栖菜和海带3种不同提取方法得出:乙醇提取物对两种菌体的抑菌活性相对水提物和乙醚提取物较好,且乙醇提取物乙酸乙酯相对水相抑菌活性较好;比较羊栖菜和海带乙醇提取物乙酸乙酯相的MIC得出:海带对大肠埃希菌和金黄色葡萄球菌的MIC相对羊栖菜较低,抑菌效果较好。展开更多
Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminaria japonica, an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, ...Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminaria japonica, an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, phosphorylated, and aminated fucoidan) was examined using in-vitro anticoagulant systems. The correlation between chemical variations within the fucoidan group and anticoagulant activity was determined. The in-vitro anticoagulant properties of fucoidan and its derivatives were determined by measuring activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT). The results indicate anticoagulant activity in all samples using APTT and TT assays; however, only the fucoidan derivatives affected the PT assay. Thus, the fucoidan derivatives were able to inhibit both intrinsic and extrinsic blood coagulants. Fucoidan (FPS) and its derivatives presented better anticoagulant activity than low molecular weight fucoidan (DFPS) and its derivatives, suggesting that molecular weight and proper conformation are contributing factors for anticoagulant activity of polysaccharides. Amino groups have a positive charge and can thus change the charge density of fucoidan. Accordingly, among the tested samples, aminated fucoidan (NF) was the most active reflecting the importance of charge density for anticoagulant activity. Available data obtained using in-vitro models suggest that the sulfate content, sulfate/total-sugar ratio, molecular weight, and the substituted group of fucoidan are important factors for anticoagulant activity but that the influence of sulfate, phosphate and amino groups on anticoagulant activity was different.展开更多
In the present study, ultrasonic extraction technique(UET) is used to improve the yield of polysaccharides from Laminaria japonica(LJPs). And their antioxidative as well as glycosidase inhibitory activities are invest...In the present study, ultrasonic extraction technique(UET) is used to improve the yield of polysaccharides from Laminaria japonica(LJPs). And their antioxidative as well as glycosidase inhibitory activities are investigated. Box-Behnken design(BBD) combined with response surface methodology(RSM) is applied to optimize ultrasonic extraction for polysaccharides. The optimized conditions are obtained as extraction time at 54 min, ultrasonic power at 1050 W, extraction temperature at 80℃ and ratio of material to solvent at 1:50(g m L-1). Under these optimal ultrasonic extraction conditions, an actual experimental yield(5.75% ± 0.3%) is close to the predicted result(5.67%) with no significant difference(P > 0.05). Vitro antioxidative and glycosidase inhibitory activities tests indicate that the crude polysaccharides(LJP) and two major ethanol precipitated fractions(LJP1 and LJP2) are in a concentration-dependent manner. LJP2(30%-60% ethanol precipitated polysaccharides) possesses the strongest α-glucosidase inhibitory activity and moderate scavenging activity against hydroxyl radicals(66.09% ± 2.19%, 3.0 mg m L-1). Also, the inhibitory activity against α-glucosidase(59.08% ± 3.79%, 5.0 mg m L-1) is close to that of acarbose(63.99% ± 3.27%, 5.0 mg m L-1). LJP1(30% ethanol precipitated polysaccharides) exhibits the strongest scavenging activity against hydroxyl radicals(99.80% ± 0.00%, 3.0 mgm L-1) and moderate α-glucosidase inhibitory activity(47.76% ± 1.92%, 5.0 mg m L-1). LJP shows the most remarkable DPPH scavenging activity(66.20% ± 0.11%, 5.0 mg m L-1) but weakest α-glucosidase inhibitory activity(37.77% ± 1.30%, 5.0 mg m L-1). However, all these LJPs exert weak inhibitory effects against α-amylase. These results show that UET is an effective method for extracting bioactive polysaccharides from seaweed materials. LJP1 and LJP2 can be developed as a potential ingredient in hypoglycemic agents or functional food for the management of diabetes. This study provides scientific evidence and advances in the preparation technology and a hypoglycemic activities evaluation method for seaweed polysaccharides, especially glycosidase inhibition in combination with an antioxidative activity evaluation method.展开更多
文摘Fucoxanthin was extracted from the intact rhizoid of Laminariajaponica Aresch with dimethylsulfoxide (DMSO), and then recovered from the DMSO extract by partitioning into ethyl acetate and subse-quent evaporation. Some isolation conditions such as solvent volume and extraction time were screened.The quantity and quality of the extracted fucoxanthin were determined by spectral analysis (absorptionspectra and fluorescence emission spectra). The results indicated that: (1) the average total content offucoxanthin was 122.1 μg in 1 g of fresh L. japonica rhizoid; (2) in comparison with the widely used organicsolvent, acetone, DMSO was much more effective for the extraction of fucoxanthin; (3) both DMSO volumeand extraction time influenced extraction efficiency such as the recovery rate and purity of fucoxanthin (1 gpurity 0.63); (4) when (NH4)2SO4 concentration was in the range of 0.5-1.0 mol/L, the pigments rapidly andentirely moved from DMSO into the ethyl acetate phase; (5) the ethyl acetate and DMSO were recycledusing a rotary evaporator.
文摘本实验以金黄色葡萄球菌(St aphyl occoccus aureaus Rosenbach)、大肠埃希菌(Escheri-chi a col i)2种需氧型细菌作为供试细菌,用圆形纸片法对羊栖菜和海带的无菌水、乙醚和乙醇提取物进行抑菌试验。结果表明:采用水提法、95%乙醇浸提取法和乙醚索氏提取法均能从羊栖菜和海带中提取出活性物质,提取回收率依次为水提法>乙醇提法>乙醚提法;比较对羊栖菜和海带3种不同提取方法得出:乙醇提取物对两种菌体的抑菌活性相对水提物和乙醚提取物较好,且乙醇提取物乙酸乙酯相对水相抑菌活性较好;比较羊栖菜和海带乙醇提取物乙酸乙酯相的MIC得出:海带对大肠埃希菌和金黄色葡萄球菌的MIC相对羊栖菜较低,抑菌效果较好。
基金Supported by the Ocean Public Welfare Scientific Research Project, State Oceanic Administration of the People's Republic of China (No. 201005024)
文摘Fucoidan, a group of sulfated heteropolysaccharides, was extracted from Laminaria japonica, an important economic alga species in China. The anticoagulant activity of fucoidan and its derivatives (including sulfated, phosphorylated, and aminated fucoidan) was examined using in-vitro anticoagulant systems. The correlation between chemical variations within the fucoidan group and anticoagulant activity was determined. The in-vitro anticoagulant properties of fucoidan and its derivatives were determined by measuring activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT). The results indicate anticoagulant activity in all samples using APTT and TT assays; however, only the fucoidan derivatives affected the PT assay. Thus, the fucoidan derivatives were able to inhibit both intrinsic and extrinsic blood coagulants. Fucoidan (FPS) and its derivatives presented better anticoagulant activity than low molecular weight fucoidan (DFPS) and its derivatives, suggesting that molecular weight and proper conformation are contributing factors for anticoagulant activity of polysaccharides. Amino groups have a positive charge and can thus change the charge density of fucoidan. Accordingly, among the tested samples, aminated fucoidan (NF) was the most active reflecting the importance of charge density for anticoagulant activity. Available data obtained using in-vitro models suggest that the sulfate content, sulfate/total-sugar ratio, molecular weight, and the substituted group of fucoidan are important factors for anticoagulant activity but that the influence of sulfate, phosphate and amino groups on anticoagulant activity was different.
基金supported by the Project of National Key Technology Research and Development Program for the 12th Five-year Plan(No.2012BAD33B10)Public Science and Technology Research Funds Projects of Ocean(No.201305018-2)+4 种基金the Innovative Development of Marine Economy Regional Demonstration Projects(Nos.SZHY2012-B01-004,GD2013-B03-001)the National Scien-ce Foundation for Young Scientists of China(No.31101271)the Natural Science Foundation of Guangdong Province(Nos.2014A030310338,2014A030310351)the Comprehensive Strategic Cooperation Programs between the Guangdong Province and Chinese Academy of Sciences(No.2011B090300057)the Frontier Science Program for Young Scientists of South China Sea Institute of Oceanology,Chinese Academy of Science(No.SQ 201017)
文摘In the present study, ultrasonic extraction technique(UET) is used to improve the yield of polysaccharides from Laminaria japonica(LJPs). And their antioxidative as well as glycosidase inhibitory activities are investigated. Box-Behnken design(BBD) combined with response surface methodology(RSM) is applied to optimize ultrasonic extraction for polysaccharides. The optimized conditions are obtained as extraction time at 54 min, ultrasonic power at 1050 W, extraction temperature at 80℃ and ratio of material to solvent at 1:50(g m L-1). Under these optimal ultrasonic extraction conditions, an actual experimental yield(5.75% ± 0.3%) is close to the predicted result(5.67%) with no significant difference(P > 0.05). Vitro antioxidative and glycosidase inhibitory activities tests indicate that the crude polysaccharides(LJP) and two major ethanol precipitated fractions(LJP1 and LJP2) are in a concentration-dependent manner. LJP2(30%-60% ethanol precipitated polysaccharides) possesses the strongest α-glucosidase inhibitory activity and moderate scavenging activity against hydroxyl radicals(66.09% ± 2.19%, 3.0 mg m L-1). Also, the inhibitory activity against α-glucosidase(59.08% ± 3.79%, 5.0 mg m L-1) is close to that of acarbose(63.99% ± 3.27%, 5.0 mg m L-1). LJP1(30% ethanol precipitated polysaccharides) exhibits the strongest scavenging activity against hydroxyl radicals(99.80% ± 0.00%, 3.0 mgm L-1) and moderate α-glucosidase inhibitory activity(47.76% ± 1.92%, 5.0 mg m L-1). LJP shows the most remarkable DPPH scavenging activity(66.20% ± 0.11%, 5.0 mg m L-1) but weakest α-glucosidase inhibitory activity(37.77% ± 1.30%, 5.0 mg m L-1). However, all these LJPs exert weak inhibitory effects against α-amylase. These results show that UET is an effective method for extracting bioactive polysaccharides from seaweed materials. LJP1 and LJP2 can be developed as a potential ingredient in hypoglycemic agents or functional food for the management of diabetes. This study provides scientific evidence and advances in the preparation technology and a hypoglycemic activities evaluation method for seaweed polysaccharides, especially glycosidase inhibition in combination with an antioxidative activity evaluation method.
