In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic...In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods.展开更多
The aquaculture industry has developed significantly over the past few decades and has had a substantial impact on the global food supply and marine fisheries resources.However,some problems arise behind the scenes du...The aquaculture industry has developed significantly over the past few decades and has had a substantial impact on the global food supply and marine fisheries resources.However,some problems arise behind the scenes due to excessive intensive farming,such as slow animal growth,frequent disease,and lipid metabolism disorders.These problems have limited the sustainable development of the aquaculture industry,and a continuable solution is required.The use of fungal polysaccharide appears to provide a solution to these problems.Therefore,different supplemented levels of Poria cocos polysaccharide(PCP)(0,0.4,0.8,1.2,1.6,and 2.0 g/kg,respectively)were fed to spotted sea bass(Lateolabrax maculatus)in similar size(30.28±0.18 g)in current study.The effects of PCP on growth,physiological parameters,and lipid metabolism of spotted sea bass were investigated after a 4-week rearing period.Results showed,fish with PCP intake presented a significantly higher weight gain,specific growth rate,and a significantly lower feed conversion ratio.Significantly higher trypsin activity in liver and intestine were observed in fish with PCP intake.The superoxide dismutase activity in serum and liver of fish with PCP intake were significantly improved,while significantly higher serum total antioxidant capacity and hepatic catalase activity were also observed.However,no significant differences in lysozyme and alkaline phosphatase activity were evident among groups.Fish with PCP intake showed a significantly lower total cholesterol,but no noteworthy change in triglyceride and lipid-metabolismrelated genes expression were observed among groups.Results indicated that intake of PCP has a positive effect on growth and antioxidant capacity of spotted sea bass,but seems to have a limited effect on the non-specific immunity and lipid metabolism of spotted sea bass.Based on the regression analysis results,1.4 g/kg of PCP is the optimal dose for spotted sea bass in size(30.28±0.18 g).展开更多
The antineoplastic activity of polysaccharide was investigated in Stichopus chlorontus, Isostichopus badionotus, Stichopus horrens and Holothuria lessoni massin. Crude polysaccharide was prepared with enzyme hydrolyza...The antineoplastic activity of polysaccharide was investigated in Stichopus chlorontus, Isostichopus badionotus, Stichopus horrens and Holothuria lessoni massin. Crude polysaccharide was prepared with enzyme hydrolyzation method and purified by anion exchange chromatography using DEAE-sepharose fast flow column. The effect of polysaccharide on cells apoptosis of SiHa and U87 was examined with cell counting kit-8 colorimetry method. Western blotting was used to analyze related proteins of cellular apoptosis including p53 and Bcl-2. Results showed that there were two main components in each sea cucumber polysaccharide, which could be eluted down by 1.0 mol/LNaCl solution. The four types of polysaccharide in the second component were named as SC-2, IB-2, HLM-2 and SH-2, respectively. They were used for comparing the antineoplastic activity. Results showed that SC-2, IB-2, HLM-2 and SH-2 could promote apoptosis of U87 and SiHa cells. SH-2 and HLM-2 were selected for the subsequent experiment to explore the additional effect of U87 and SiHa cells, The protein expressions of Bcl-2 and p53 decreased considerably with the increase of polysaccharide concentration in U87 cells. In SiHa cells, protein expressions of Bcl-2 and high dosage group of p53 decreased significantly, whereas no obvious decrease was observed in other groups. The polysaccharides are more effective in promoting apoptosis of U87 and SiHa cells from S. horrens and H. lessoni massin than from the rest species.展开更多
Enzymatic hydrolysis has been widely used to produce bioactive hydrolysates from sea cucumber body wall.Here,inspired by the clarification of Apostichopus japonicus genome,we investigated the enzymatic hydrolysis of s...Enzymatic hydrolysis has been widely used to produce bioactive hydrolysates from sea cucumber body wall.Here,inspired by the clarification of Apostichopus japonicus genome,we investigated the enzymatic hydrolysis of sea cucumber body wall by using the omics strategy.Shared proteins,including major yolk proteins,collagens,extracellular matrix glycoproteins and muscle proteins,were released from the body wall by different hydrolysis condition.A portfolio of 216 shared peptides were detected in the peptidome by papain with different hydrolysis time,while 32 shared peptides were detected in the peptidome by differing proteases.Unshared peptides and the relative abundance distribution profiles of shared peptides changed depending on hydrolysis approaches,indicating dynamic changes of peptidome during hydrolysis.Moreover,release of sulfated fucan and fucosylated chondroitin sulfate changed with the hydrolysis condition.The monitoring of dynamic enzymatic hydrolysis process at a molecular scale would contribute to production and quality control of sea cucumber hydrolysates.展开更多
Sea cucumber is a traditional nutritional food and medicinal resource with many bioactive components in China.Holothuria fuscogliva is a big sea cucumber with a rich of bioactive polysaccharides.To investigate the bio...Sea cucumber is a traditional nutritional food and medicinal resource with many bioactive components in China.Holothuria fuscogliva is a big sea cucumber with a rich of bioactive polysaccharides.To investigate the bioactivities of the polysaccharides from sea cucumber H.fuscogliva,we prepared the sulfated polysaccharides(HfP) from sea cucumber H.fuscogliva using a protease hydrolysis method.Antioxidant activities of HfP were investigated,including hydroxyl radical scavenging activity and superoxide radical scavenging activity.And,the anticoagulant activities of HfP were studied,including the activated partial thromboplastin time(APTT),prothrombin time(PT) and thrombin time(TT).The average molecular weight was 1 867.1 Da,with a sulfate content of 20.7%.In addition,the molar ratio of monosaccharide composition of HfP was Man:Rha:Glc A:Glc:Gal:Xyl:Fuc=0.083 6:0.437:0.134:0:1.182:0.748:1.It had a strong antioxidant activity,the hydroxyl and superoxide radical scavenging activity EC_(50) of HfP was 3.74 and 0.037 mg/mL,respectively.It also showed a good anticoagulant activity in our study.The APTT of HfP was much higher than that of heparin sodium,and the PT and TT of HfP was close to that of heparin sodium at a low concentration.Therefore,HfP shows a good antioxidant and anticoagulant activity and it may become a potential candidate of the natural antioxidant and anticoagulant and will have a good application future in health product or medicine industry.展开更多
Aim: To evaluate the clinical efficacy of the traditional Chinese medicine sea buckthorn (SBT) in the treatment of patients with nonalcoholic fatty liver disease (NAFLD). Method: 94 patients with NAFLD were randomly d...Aim: To evaluate the clinical efficacy of the traditional Chinese medicine sea buckthorn (SBT) in the treatment of patients with nonalcoholic fatty liver disease (NAFLD). Method: 94 patients with NAFLD were randomly divided into two groups: 48 cases of patients received oral sea buckthorn 1.5 g (3 times a day) for three months as the treated group, and 46 cases received only the vehicle for three months as the control group. Serum lipids, transaminase and serum liver fibrosis indices were assessed at baseline and after SBT treatment. All patients underwent liver CT and Fibroscan examination at baseline and after treatment. Results: SBT treatment resulted in a significant decrease in the serum levels of alanine aminotransferase (ALT), LDL-C, hyaluronic acid and collagen type IV. The liver stiffness measurement (LSM) of the treated patients was significantly lower than that in the control or baseline. The CT liver/spleen ratio of the treated patients was also significantly increased. Conclusion: The results of our study demonstrated the beneficial effects of SBT on serum lipids, transaminase, and liver/spleen ratio and liver stiffness in patients with NAFLD, which may be further developed as a promising therapy for the treatment of NAFLD.展开更多
Sea buckthorn market floated uncertainly within a narrow range. The market situation provided upward pressure on prices, and producer and consumer interest were poor, coupled with weak prices in the regional markets. ...Sea buckthorn market floated uncertainly within a narrow range. The market situation provided upward pressure on prices, and producer and consumer interest were poor, coupled with weak prices in the regional markets. The objectives of the study are: 1) to estimate the relationship between wild Sea buckthorn (SB) price and Supply, Demand, while some other factors of crude oil price and exchange rate by using simultaneous Supply-Demand and Price system equation and Vector Error Correction Method (VECM);2) to forecast the short-term and long-term SB price;3) to compare and evaluate the price forecasting models. Firstly, the data was analyzed by Ferris and Engle-Granger’s procedure;secondly, both price forecasting methodologies were tested by Pindyck-Rubinfeld and Makridakis’s procedure. The result shows that the VECM model is more efficient using yearly data;a short-term price forecast decreases, and a long-term price forecast is predicted to increase the Mongolian Sea buckthorn market.展开更多
Objective: This study is designed to observe the chronic toxicity after the administration of mulberry sea-buckthorn beverage concentrate for 3 months on rats and to predict the possible adverse effect and the potenti...Objective: This study is designed to observe the chronic toxicity after the administration of mulberry sea-buckthorn beverage concentrate for 3 months on rats and to predict the possible adverse effect and the potential toxicity target organs. Method: The rats (SPF level) were randomly divided into high-dose (20 mL/kg BW), middle-dose (10 mL/kg BW), low-dose (5 mL/kg BW) groups and negative control group (20 mL/kg BW of purified water) with 30 rats in each group. Each group was orally given mulberry sea-buckthorn beverage concentrate for 3 months and recovered by stop feeding samples for 2 weeks for a recovery observation. The rats’ general condition, the organ coefficient, the indexes of hematology and blood biochemistry and the histological changes of the main organs were determined. Result: The appearance and behavior of activity in rats showed no anomalies in all these groups and all the rats put on weight during this period. Comparing to the negative control group, no obvious differences were observed in the weekly weight and organ coefficient of each dose group. After 3 months of administration, HGB in both mulberry sea-buckthorn beverage concentrate low-dose group and high-dose group were increased. No significant differences were observed in the indexes of hematology after 2 weeks of recovery. CREA in low-dose, middle-dose and high-dose groups were significantly increased after 3 months of administration and it remained in the high level in middle-dose and high-dose group even after 2 weeks of recovery. No drug-related lesions were observed in the histological changes of major organs. Conclusion: The results show that long term use of mulberry concentrated sea-buckthorn beverage can lead to increased CREA, which suggested kidney toxicity. Although no obvious pathological change was found in kidney, we should pay attention to chronic kidney damage in the further research.展开更多
2,4,6-Tripyridine-s-triazine(TPTZ)spectrophotometric method was applied to determine the concentrations of dissolved monosaccharides(MCHO),polysaccharides(PCHO),and total carbohydrate(TCHO)in seawater samples collecte...2,4,6-Tripyridine-s-triazine(TPTZ)spectrophotometric method was applied to determine the concentrations of dissolved monosaccharides(MCHO),polysaccharides(PCHO),and total carbohydrate(TCHO)in seawater samples collected from sea surface to hadal zone and sediment-seawater interface of the Southern Yap Trench in the Western Pacific Ocean.Results show that the concentrations of MCHO,PCHO,and TCHO ranged from 6.3 to 22.3μmol C/L,1.1 to 25.4μmol C/L,and 12.1 to 44.9μmol C/L,respectively,from the euphotic layer to the hadal zone of the trench.At different sampling stations,the concentrations of MCHO,PCHO,and TCHO in the seawater showed complex vertical variation characteristics,but the overall variation trends were decreasing with water depth.In the Southern Yap Trench,the maximum concentration of MCHO in the seawater appeared in the euphotic layer,and the minimum in the hadal zone.The maximum concentration of PCHO appeared in the euphotic layer,and the minimum in the bathypelagic layer.The water layer where the maxima and minima of the average concentration of TCHO appeared was consistent with that of PCHO.PCHO was the major component of TCHO in the seawater of the Southern Yap Trench.In the seawater from the sediment-seawater interface,the concentrations of MCHO,PCHO,and TCHO ranged from 8.4 to 10.6μmol C/L,3.8 to 5.8μmol C/L,and 12.2 to 15.2μmol C/L,respectively,and MCHO was the major component of TCHO.The key factors affecting the concentration and existing forms of dissolved sugars in the seawater of the Southern Yap Trench included photosynthesis,respiration,polysaccharide hydrolysis,adsorption and desorption of particulate matter,trench“funnel effect”,deep ocean currents,sediment resuspension,and etc.This study provided fundamental data about labile organic matter in abyss and hadal zone of marine environment,which is significant for further understanding of deep-sea organic carbon cycle.展开更多
基金The Guangdong Basic and Applied Basic Research Foundation(2022A1515010730)National Natural Science Foundation of China(32001647)+2 种基金National Natural Science Foundation of China(31972022)Financial and moral assistance supported by the Guangdong Basic and Applied Basic Research Foundation(2019A1515011996)111 Project(B17018)。
文摘In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods.
基金the Science and Technology Planning Project in FujianChina(No.2015N0010)+1 种基金the Science and Technology Planning Project in XiamenChina(No.3502Z20143017)。
文摘The aquaculture industry has developed significantly over the past few decades and has had a substantial impact on the global food supply and marine fisheries resources.However,some problems arise behind the scenes due to excessive intensive farming,such as slow animal growth,frequent disease,and lipid metabolism disorders.These problems have limited the sustainable development of the aquaculture industry,and a continuable solution is required.The use of fungal polysaccharide appears to provide a solution to these problems.Therefore,different supplemented levels of Poria cocos polysaccharide(PCP)(0,0.4,0.8,1.2,1.6,and 2.0 g/kg,respectively)were fed to spotted sea bass(Lateolabrax maculatus)in similar size(30.28±0.18 g)in current study.The effects of PCP on growth,physiological parameters,and lipid metabolism of spotted sea bass were investigated after a 4-week rearing period.Results showed,fish with PCP intake presented a significantly higher weight gain,specific growth rate,and a significantly lower feed conversion ratio.Significantly higher trypsin activity in liver and intestine were observed in fish with PCP intake.The superoxide dismutase activity in serum and liver of fish with PCP intake were significantly improved,while significantly higher serum total antioxidant capacity and hepatic catalase activity were also observed.However,no significant differences in lysozyme and alkaline phosphatase activity were evident among groups.Fish with PCP intake showed a significantly lower total cholesterol,but no noteworthy change in triglyceride and lipid-metabolismrelated genes expression were observed among groups.Results indicated that intake of PCP has a positive effect on growth and antioxidant capacity of spotted sea bass,but seems to have a limited effect on the non-specific immunity and lipid metabolism of spotted sea bass.Based on the regression analysis results,1.4 g/kg of PCP is the optimal dose for spotted sea bass in size(30.28±0.18 g).
基金supported by Fund of Key Laboratory of Aquatic Product Processing,Ministry of Agriculture,China(No.NYJG201505)Special Scientific Re search Funds for Central Non-profit Institutes,Chinese Academy of Fishery Sciences(No.2016HY-ZD0801)
文摘The antineoplastic activity of polysaccharide was investigated in Stichopus chlorontus, Isostichopus badionotus, Stichopus horrens and Holothuria lessoni massin. Crude polysaccharide was prepared with enzyme hydrolyzation method and purified by anion exchange chromatography using DEAE-sepharose fast flow column. The effect of polysaccharide on cells apoptosis of SiHa and U87 was examined with cell counting kit-8 colorimetry method. Western blotting was used to analyze related proteins of cellular apoptosis including p53 and Bcl-2. Results showed that there were two main components in each sea cucumber polysaccharide, which could be eluted down by 1.0 mol/LNaCl solution. The four types of polysaccharide in the second component were named as SC-2, IB-2, HLM-2 and SH-2, respectively. They were used for comparing the antineoplastic activity. Results showed that SC-2, IB-2, HLM-2 and SH-2 could promote apoptosis of U87 and SiHa cells. SH-2 and HLM-2 were selected for the subsequent experiment to explore the additional effect of U87 and SiHa cells, The protein expressions of Bcl-2 and p53 decreased considerably with the increase of polysaccharide concentration in U87 cells. In SiHa cells, protein expressions of Bcl-2 and high dosage group of p53 decreased significantly, whereas no obvious decrease was observed in other groups. The polysaccharides are more effective in promoting apoptosis of U87 and SiHa cells from S. horrens and H. lessoni massin than from the rest species.
基金supported by the Fok Ying-Tong Education Foundation (171024)Fundamental Research Funds for the Central Universities (201941005)Fundamental Research Funds for the Central Universities (862001013136)。
文摘Enzymatic hydrolysis has been widely used to produce bioactive hydrolysates from sea cucumber body wall.Here,inspired by the clarification of Apostichopus japonicus genome,we investigated the enzymatic hydrolysis of sea cucumber body wall by using the omics strategy.Shared proteins,including major yolk proteins,collagens,extracellular matrix glycoproteins and muscle proteins,were released from the body wall by different hydrolysis condition.A portfolio of 216 shared peptides were detected in the peptidome by papain with different hydrolysis time,while 32 shared peptides were detected in the peptidome by differing proteases.Unshared peptides and the relative abundance distribution profiles of shared peptides changed depending on hydrolysis approaches,indicating dynamic changes of peptidome during hydrolysis.Moreover,release of sulfated fucan and fucosylated chondroitin sulfate changed with the hydrolysis condition.The monitoring of dynamic enzymatic hydrolysis process at a molecular scale would contribute to production and quality control of sea cucumber hydrolysates.
基金Supported by the Science and Technology Service Network Program of Chinese Academy of Sciences(No.KFJ-EW-STS-060)the National Special Research Fund for Non-Profit Marine Sector(No.201405038-2)+1 种基金the Scientific and Technological Innovation ProjectFinancially Supported by Qingdao National Laboratory for Marine Science and Technology(No.2015ASKJ02)
文摘Sea cucumber is a traditional nutritional food and medicinal resource with many bioactive components in China.Holothuria fuscogliva is a big sea cucumber with a rich of bioactive polysaccharides.To investigate the bioactivities of the polysaccharides from sea cucumber H.fuscogliva,we prepared the sulfated polysaccharides(HfP) from sea cucumber H.fuscogliva using a protease hydrolysis method.Antioxidant activities of HfP were investigated,including hydroxyl radical scavenging activity and superoxide radical scavenging activity.And,the anticoagulant activities of HfP were studied,including the activated partial thromboplastin time(APTT),prothrombin time(PT) and thrombin time(TT).The average molecular weight was 1 867.1 Da,with a sulfate content of 20.7%.In addition,the molar ratio of monosaccharide composition of HfP was Man:Rha:Glc A:Glc:Gal:Xyl:Fuc=0.083 6:0.437:0.134:0:1.182:0.748:1.It had a strong antioxidant activity,the hydroxyl and superoxide radical scavenging activity EC_(50) of HfP was 3.74 and 0.037 mg/mL,respectively.It also showed a good anticoagulant activity in our study.The APTT of HfP was much higher than that of heparin sodium,and the PT and TT of HfP was close to that of heparin sodium at a low concentration.Therefore,HfP shows a good antioxidant and anticoagulant activity and it may become a potential candidate of the natural antioxidant and anticoagulant and will have a good application future in health product or medicine industry.
文摘Aim: To evaluate the clinical efficacy of the traditional Chinese medicine sea buckthorn (SBT) in the treatment of patients with nonalcoholic fatty liver disease (NAFLD). Method: 94 patients with NAFLD were randomly divided into two groups: 48 cases of patients received oral sea buckthorn 1.5 g (3 times a day) for three months as the treated group, and 46 cases received only the vehicle for three months as the control group. Serum lipids, transaminase and serum liver fibrosis indices were assessed at baseline and after SBT treatment. All patients underwent liver CT and Fibroscan examination at baseline and after treatment. Results: SBT treatment resulted in a significant decrease in the serum levels of alanine aminotransferase (ALT), LDL-C, hyaluronic acid and collagen type IV. The liver stiffness measurement (LSM) of the treated patients was significantly lower than that in the control or baseline. The CT liver/spleen ratio of the treated patients was also significantly increased. Conclusion: The results of our study demonstrated the beneficial effects of SBT on serum lipids, transaminase, and liver/spleen ratio and liver stiffness in patients with NAFLD, which may be further developed as a promising therapy for the treatment of NAFLD.
文摘Sea buckthorn market floated uncertainly within a narrow range. The market situation provided upward pressure on prices, and producer and consumer interest were poor, coupled with weak prices in the regional markets. The objectives of the study are: 1) to estimate the relationship between wild Sea buckthorn (SB) price and Supply, Demand, while some other factors of crude oil price and exchange rate by using simultaneous Supply-Demand and Price system equation and Vector Error Correction Method (VECM);2) to forecast the short-term and long-term SB price;3) to compare and evaluate the price forecasting models. Firstly, the data was analyzed by Ferris and Engle-Granger’s procedure;secondly, both price forecasting methodologies were tested by Pindyck-Rubinfeld and Makridakis’s procedure. The result shows that the VECM model is more efficient using yearly data;a short-term price forecast decreases, and a long-term price forecast is predicted to increase the Mongolian Sea buckthorn market.
文摘Objective: This study is designed to observe the chronic toxicity after the administration of mulberry sea-buckthorn beverage concentrate for 3 months on rats and to predict the possible adverse effect and the potential toxicity target organs. Method: The rats (SPF level) were randomly divided into high-dose (20 mL/kg BW), middle-dose (10 mL/kg BW), low-dose (5 mL/kg BW) groups and negative control group (20 mL/kg BW of purified water) with 30 rats in each group. Each group was orally given mulberry sea-buckthorn beverage concentrate for 3 months and recovered by stop feeding samples for 2 weeks for a recovery observation. The rats’ general condition, the organ coefficient, the indexes of hematology and blood biochemistry and the histological changes of the main organs were determined. Result: The appearance and behavior of activity in rats showed no anomalies in all these groups and all the rats put on weight during this period. Comparing to the negative control group, no obvious differences were observed in the weekly weight and organ coefficient of each dose group. After 3 months of administration, HGB in both mulberry sea-buckthorn beverage concentrate low-dose group and high-dose group were increased. No significant differences were observed in the indexes of hematology after 2 weeks of recovery. CREA in low-dose, middle-dose and high-dose groups were significantly increased after 3 months of administration and it remained in the high level in middle-dose and high-dose group even after 2 weeks of recovery. No drug-related lesions were observed in the histological changes of major organs. Conclusion: The results show that long term use of mulberry concentrated sea-buckthorn beverage can lead to increased CREA, which suggested kidney toxicity. Although no obvious pathological change was found in kidney, we should pay attention to chronic kidney damage in the further research.
基金Supported by the National Key Research and Development Program of China(No.2022YFC2803803)the National Natural Science Foundation of China(No.42076040)the National Basic Research Program of China(973 Program)(No.2015CB755904)。
文摘2,4,6-Tripyridine-s-triazine(TPTZ)spectrophotometric method was applied to determine the concentrations of dissolved monosaccharides(MCHO),polysaccharides(PCHO),and total carbohydrate(TCHO)in seawater samples collected from sea surface to hadal zone and sediment-seawater interface of the Southern Yap Trench in the Western Pacific Ocean.Results show that the concentrations of MCHO,PCHO,and TCHO ranged from 6.3 to 22.3μmol C/L,1.1 to 25.4μmol C/L,and 12.1 to 44.9μmol C/L,respectively,from the euphotic layer to the hadal zone of the trench.At different sampling stations,the concentrations of MCHO,PCHO,and TCHO in the seawater showed complex vertical variation characteristics,but the overall variation trends were decreasing with water depth.In the Southern Yap Trench,the maximum concentration of MCHO in the seawater appeared in the euphotic layer,and the minimum in the hadal zone.The maximum concentration of PCHO appeared in the euphotic layer,and the minimum in the bathypelagic layer.The water layer where the maxima and minima of the average concentration of TCHO appeared was consistent with that of PCHO.PCHO was the major component of TCHO in the seawater of the Southern Yap Trench.In the seawater from the sediment-seawater interface,the concentrations of MCHO,PCHO,and TCHO ranged from 8.4 to 10.6μmol C/L,3.8 to 5.8μmol C/L,and 12.2 to 15.2μmol C/L,respectively,and MCHO was the major component of TCHO.The key factors affecting the concentration and existing forms of dissolved sugars in the seawater of the Southern Yap Trench included photosynthesis,respiration,polysaccharide hydrolysis,adsorption and desorption of particulate matter,trench“funnel effect”,deep ocean currents,sediment resuspension,and etc.This study provided fundamental data about labile organic matter in abyss and hadal zone of marine environment,which is significant for further understanding of deep-sea organic carbon cycle.
