The prevalence of obesity has increased and is a health concern worldwide.Due to the concerns regarding synthetic anti-obesity treatments,nowadays natural products become a trend.Previous studies proved that there is ...The prevalence of obesity has increased and is a health concern worldwide.Due to the concerns regarding synthetic anti-obesity treatments,nowadays natural products become a trend.Previous studies proved that there is a potential to use marine algae as anti-obesity agents.Therefore,in this study,the lipid inhibitory effect of crude polysaccharide of amyloglucosidase-assisted hydrolysate from Sargassum thunbergii(STAC)and its fucoidan fractions(STAFs)on 3T3-L1 cells and high-fat diet(HFD)-induced obese mice were investigated.According to the results,the STAF3,showed the highest xylose content and exhibited significant inhibitory effects on lipid accumulation by downregulating adipogenic and lipogenic proteins in 3T3-L1 cells.Furthermore,oral supplementation with STAC significantly declined gain in body weight and fat weight,and serum lipid contents in an HFD-induced obesity mouse model.Structural and chemical characterizations demonstrated that puritied STAF3 has consistent surface morphology and small particle size,with similar structural characteristics as commercial fucoidan.Together,these results indicate that STAC and purified STAF3 from Sargassum thunbergia is a potent source to develop as ananti-obesity agents or functional food products to counter obesity.展开更多
Artificial seedling production of Sargassum thunbergii is an effective way to relieve pressure on natural resources.In order to improve the utilization of zygotes and reduce the loss of seedlings,studies on the charac...Artificial seedling production of Sargassum thunbergii is an effective way to relieve pressure on natural resources.In order to improve the utilization of zygotes and reduce the loss of seedlings,studies on the characteristic of the zygotes release,the development of rhizoids,the attachment of germlings,and the influence of jet washing were conducted.Results show that the percent of zygotes released was increased with time in the first 60 h.The capacity of germlings attached to the substratum was significantly increased,especially coincident with the time of the new rhizoids emerged and elongated.The detachment rate of germlings significantly decreased with the delay of starting time of jet washing or the reduction of jet washing velocity.However,the jet washing at any level applied in the experiment could cause considerable loss of germlings within the 20 days after the attachment.Our study provided some parameters to optimize the operation in the early stage of seedling production.展开更多
Heavy metal pollution in aquatic system is becoming a serious problem worldwide. In this study, responses of Sargassum thunbergii to dif ferent concentrations(0, 0.1, 0.5, 1.0 and 5.0 mg/L) of zinc(Zn) and cadmium(Cd)...Heavy metal pollution in aquatic system is becoming a serious problem worldwide. In this study, responses of Sargassum thunbergii to dif ferent concentrations(0, 0.1, 0.5, 1.0 and 5.0 mg/L) of zinc(Zn) and cadmium(Cd) exposure separately were studied for 15 days in laboratory-controlled conditions. The results show that the specifi c growth rates increased slightly under the lower Zn concentration treatment(0.1 mg/L) at the first 5 d and then decreased gradually, which were significantly reduced with the exposure time in higher Zn concentrations and all Cd treatments compared to respective control, especially for 1.0 and 5.0 mg/L Cd. Chlorophyll a contents showed significant increase in 0.1 mg/L Zn treatment, whereas the gradually reduction were observed in the other three Zn treatments and all Cd treatments. The oxygen evolution rate and respiration rate presented distinct behavior in the Zn-treated samples, but both declined steadily with the exposure time in Cd treatments. The P/R value analyses showed similar variation patterns as chlorophyll a contents. Real-time PCR showed that lower Zn concentration(0.1 mg/L) increased mRNA expression of rbcL gene, whereas higher Zn concentrations and Cd reduced the rbcL expression. Taken together, these findings strongly indicate that Zn and Cd had different effects on S. thunbergii both at the physiological and gene transcription levels, the transcript level of photosynthesis-related gene rbcL can be used as an useful molecular marker of algal growth and environment impacts.展开更多
We conducted a phenological evaluation of Sargassum thunbergii,a common algal species,along the coast of Lidao Bay,Rongcheng,China.The local S.thunbergii population entered a maturation period from early June to mid-A...We conducted a phenological evaluation of Sargassum thunbergii,a common algal species,along the coast of Lidao Bay,Rongcheng,China.The local S.thunbergii population entered a maturation period from early June to mid-August,when seawater temperature was 14.4 to 25.1°C.Our results suggest an increase in temperature and day length during this period initiated thalli maturation.Inhabitants of the low tidal zone had higher thalli length and biomass compared with those from the mid- and high tidal zones.We observed a switch in the length frequency distribution and contribution of length classes to biomass between the small(<20 cm) and long(20–79.9 cm) length classes at the time of thallus maturity.This suggests there is a trade-offbetween sexual reproduction and vegetative regeneration.展开更多
Sargassum thunbergii is of great economic and ecological value to sea cucumber cultures and seaweed beds. However, studies on photosynthesis and respiration of S. thunbergii are limited. In this study, a liquid-phase ...Sargassum thunbergii is of great economic and ecological value to sea cucumber cultures and seaweed beds. However, studies on photosynthesis and respiration of S. thunbergii are limited. In this study, a liquid-phase oxygen electrode system and a chlorophyll fluorescence spectrometer were used to determine the photosynthetic characteristics of S. thunbergii seedlings at various light intensities, temperatures, and salinities. The light-saturated net photosynthetic rates, light saturation points, and respiratory rates of germlings were investigated. Results showed that the increase in rate of light saturation point was slow in the first 4 d, rapidly increased from 5 d to 9 d, and then gently increased at the final few days of the 15 d indoor culture period. The photosynthetic rate or respiratory rate of the seedlings rapidly and significantly decreased when the temperature was °C or >28°C. Short-term high- or low-salinity shock had significant effect on the photosynthetic and respiratory rates of the seedlings, specifically at 10 and 50 psu. However, the photosynthetic and respiratory rates recovered to the normal levels after 24 h of recovery period, which demonstrated a powerful ion-transport system of the seedlings. These results provided reference for the artificial breeding of S. thunbergii.展开更多
We evaluated the effects of high molecular-weight phlorotannins from Sargassum thunbergii(STP) on ADP-induced platelet aggregation and arachidonic acid(AA) metabolism in New Zealand white rabbits and Wistar rats.The i...We evaluated the effects of high molecular-weight phlorotannins from Sargassum thunbergii(STP) on ADP-induced platelet aggregation and arachidonic acid(AA) metabolism in New Zealand white rabbits and Wistar rats.The inhibition of STP on platelet aggregation was investigated using a turbidimetric method,and the levels of the terminal products of AA metabolism were measured using the corresponding kits for maleic dialdehyde(MDA),thromboxane B2(TXB2) and 6-keto-prostaglandin F1α(6-keto-PGF1α) by colorimetry and radioimmunoassay,as appropriate.We found that STP could inhibit ADP-induced platelet aggregation,and the inhibitory ratio was 91.50% at the STP concentration of 4.0 mg/mL.Furthermore,STP markedly affected AA metabolism by decreasing the synthesis of MDA(P<0.01) and increasing the synthesis of 6-keto-PGF1α,thus changing the plasma TXB2/6-keto-PGF1α balance when the platelets were activated(P<0.01).Therefore,STP altered AA metabolism and these findings partly revealed the molecular mechanism by which STP inhibits ADP-induced platelet aggregation.展开更多
Sargassum thunbergii is an economically important brown alga that is used as a perferred food for sea cucumber in China. However, reports on the reproductive biology of S. thunbergii are limited. This study observed t...Sargassum thunbergii is an economically important brown alga that is used as a perferred food for sea cucumber in China. However, reports on the reproductive biology of S. thunbergii are limited. This study observed the characteristics of mature receptacles. The effects of different temperatures, light intensities, and photoperiods on the egg release of mature S. thunbergii receptacles were investigated. A liquid-phase oxygen electrode system was used to obtain light saturation and light compensation points of egg and young thalli of S. thunbergii. Results showed that temperature was the key factor for the egg release of mature receptacles. The conditions most conducive to egg release were 20°C to 23°C temperature and 50 μmol photons m-2·s-1 to 200 μmol photons m-2·s-1 light intensity. In addition, the light saturation and compensation points of unfertilized eggs or young thalli at 2 d or 3 d postfertilization ranged from 90 μmol photons m-2·s-1 to 120 μmol photons m-2·s-1 and 14 μmol photons m-2·s-1 to 22 μmol photons m-2·s-1, respectively. The combined results provide a reference for the sporeling culture of S. thunbergii.展开更多
Low molecular weight polysaccharides can be isolated from Sargassum thunbergii(LMPST)and in vitro experiments were conducted to evaluate the inhibitory effects on lipids.Two natures of LMPST were attained from S.thunb...Low molecular weight polysaccharides can be isolated from Sargassum thunbergii(LMPST)and in vitro experiments were conducted to evaluate the inhibitory effects on lipids.Two natures of LMPST were attained from S.thunbergii and appraised their LMPST on palmitic acid(PA)induced lipid accretion in Hep G2,and 3T3-L1 cells.LMPST treatment lessened lipid deposition and intracellular free fatty acid and triglyceride intensities in PA-treated above mentioned cells.The mechanistic study publicized that LMPST2 significantly suppressed adipogenesis and stimulated the PA-treated 3T3-L1 cells occupied in the lipolysis pathway.Furthermore,in PA-treated Hep G2 cells,the free fatty acid oxidation was significantly increased by LMPST2.Given these constructive properties of LMPST2 from S.thunbergii,is a potential candidate for diminishing the intracellular lipids,and for a therapeutic agent in those conditions.展开更多
Results of neutron activation analysis (NAA) of Sargassum samples collected from the Qingdao Taipingjiao coast on March 20 , 1996 showed that (1) Sargassumthunbergii can to some extent potassium and calcium (the accum...Results of neutron activation analysis (NAA) of Sargassum samples collected from the Qingdao Taipingjiao coast on March 20 , 1996 showed that (1) Sargassumthunbergii can to some extent potassium and calcium (the accumulation coefficientwas 10), (2) it can accumulate all trace elements , especially iron , manganese and zinc,(3) it can accumulate strontium , aluminium thorium , and rare earth elements.展开更多
基金The“Basic Science Research Program”extended its support via the National Research Foundation of Korea (NRF),which is sponsored through the Ministry of Education (2018R1C1B6004780)supported by Main Research Program (E0211200-03)of the Korea Food Research Institute (KFRI)funded by the Ministry of Science and ICT。
文摘The prevalence of obesity has increased and is a health concern worldwide.Due to the concerns regarding synthetic anti-obesity treatments,nowadays natural products become a trend.Previous studies proved that there is a potential to use marine algae as anti-obesity agents.Therefore,in this study,the lipid inhibitory effect of crude polysaccharide of amyloglucosidase-assisted hydrolysate from Sargassum thunbergii(STAC)and its fucoidan fractions(STAFs)on 3T3-L1 cells and high-fat diet(HFD)-induced obese mice were investigated.According to the results,the STAF3,showed the highest xylose content and exhibited significant inhibitory effects on lipid accumulation by downregulating adipogenic and lipogenic proteins in 3T3-L1 cells.Furthermore,oral supplementation with STAC significantly declined gain in body weight and fat weight,and serum lipid contents in an HFD-induced obesity mouse model.Structural and chemical characterizations demonstrated that puritied STAF3 has consistent surface morphology and small particle size,with similar structural characteristics as commercial fucoidan.Together,these results indicate that STAC and purified STAF3 from Sargassum thunbergia is a potent source to develop as ananti-obesity agents or functional food products to counter obesity.
基金Supported by the Public Science and Technology Research Funds Projects of Ocean(Nos.201305021,201305043,201305005,201405040)the National Natural Science Foundation of China(No.41376129)the Scientific Funds for Outstanding Young Scientists of Shandong Province Award(No.BS2012HZ013)
文摘Artificial seedling production of Sargassum thunbergii is an effective way to relieve pressure on natural resources.In order to improve the utilization of zygotes and reduce the loss of seedlings,studies on the characteristic of the zygotes release,the development of rhizoids,the attachment of germlings,and the influence of jet washing were conducted.Results show that the percent of zygotes released was increased with time in the first 60 h.The capacity of germlings attached to the substratum was significantly increased,especially coincident with the time of the new rhizoids emerged and elongated.The detachment rate of germlings significantly decreased with the delay of starting time of jet washing or the reduction of jet washing velocity.However,the jet washing at any level applied in the experiment could cause considerable loss of germlings within the 20 days after the attachment.Our study provided some parameters to optimize the operation in the early stage of seedling production.
基金Supported by the National Natural Science Foundation of China(No.41306122)the National Special Research Fund for Non-Profit Marine Sector(Nos.201405040,201505022)+1 种基金the Scientific Funds for Outstanding Young Scientists of Shandong Province Award(No.BS2012HZ013)the Shandong Agricultural Application Technology Innovation of Research Project
文摘Heavy metal pollution in aquatic system is becoming a serious problem worldwide. In this study, responses of Sargassum thunbergii to dif ferent concentrations(0, 0.1, 0.5, 1.0 and 5.0 mg/L) of zinc(Zn) and cadmium(Cd) exposure separately were studied for 15 days in laboratory-controlled conditions. The results show that the specifi c growth rates increased slightly under the lower Zn concentration treatment(0.1 mg/L) at the first 5 d and then decreased gradually, which were significantly reduced with the exposure time in higher Zn concentrations and all Cd treatments compared to respective control, especially for 1.0 and 5.0 mg/L Cd. Chlorophyll a contents showed significant increase in 0.1 mg/L Zn treatment, whereas the gradually reduction were observed in the other three Zn treatments and all Cd treatments. The oxygen evolution rate and respiration rate presented distinct behavior in the Zn-treated samples, but both declined steadily with the exposure time in Cd treatments. The P/R value analyses showed similar variation patterns as chlorophyll a contents. Real-time PCR showed that lower Zn concentration(0.1 mg/L) increased mRNA expression of rbcL gene, whereas higher Zn concentrations and Cd reduced the rbcL expression. Taken together, these findings strongly indicate that Zn and Cd had different effects on S. thunbergii both at the physiological and gene transcription levels, the transcript level of photosynthesis-related gene rbcL can be used as an useful molecular marker of algal growth and environment impacts.
基金Supported by the National Special Research Fund for Non-Profit Marine Sector(Nos.201305021,201305043,201305005,201405040)the National Natural Science Foundation of China(No.41376129)
文摘We conducted a phenological evaluation of Sargassum thunbergii,a common algal species,along the coast of Lidao Bay,Rongcheng,China.The local S.thunbergii population entered a maturation period from early June to mid-August,when seawater temperature was 14.4 to 25.1°C.Our results suggest an increase in temperature and day length during this period initiated thalli maturation.Inhabitants of the low tidal zone had higher thalli length and biomass compared with those from the mid- and high tidal zones.We observed a switch in the length frequency distribution and contribution of length classes to biomass between the small(<20 cm) and long(20–79.9 cm) length classes at the time of thallus maturity.This suggests there is a trade-offbetween sexual reproduction and vegetative regeneration.
文摘Sargassum thunbergii is of great economic and ecological value to sea cucumber cultures and seaweed beds. However, studies on photosynthesis and respiration of S. thunbergii are limited. In this study, a liquid-phase oxygen electrode system and a chlorophyll fluorescence spectrometer were used to determine the photosynthetic characteristics of S. thunbergii seedlings at various light intensities, temperatures, and salinities. The light-saturated net photosynthetic rates, light saturation points, and respiratory rates of germlings were investigated. Results showed that the increase in rate of light saturation point was slow in the first 4 d, rapidly increased from 5 d to 9 d, and then gently increased at the final few days of the 15 d indoor culture period. The photosynthetic rate or respiratory rate of the seedlings rapidly and significantly decreased when the temperature was °C or >28°C. Short-term high- or low-salinity shock had significant effect on the photosynthetic and respiratory rates of the seedlings, specifically at 10 and 50 psu. However, the photosynthetic and respiratory rates recovered to the normal levels after 24 h of recovery period, which demonstrated a powerful ion-transport system of the seedlings. These results provided reference for the artificial breeding of S. thunbergii.
基金Supported by the National Natural Science Foundation of China (No 30572314)the Basic Research Program of Science and Technology,Ministry of Science and Technology of China (2007FY210500)+1 种基金the Program of Chinese Offshore Investigation and Assessment,State Oceanic Administration of China (Nos 908-01-ST12 and 908-02-05-04)the Science and Technology Planning Project of Qingdao (No 06-2212-JCH)
文摘We evaluated the effects of high molecular-weight phlorotannins from Sargassum thunbergii(STP) on ADP-induced platelet aggregation and arachidonic acid(AA) metabolism in New Zealand white rabbits and Wistar rats.The inhibition of STP on platelet aggregation was investigated using a turbidimetric method,and the levels of the terminal products of AA metabolism were measured using the corresponding kits for maleic dialdehyde(MDA),thromboxane B2(TXB2) and 6-keto-prostaglandin F1α(6-keto-PGF1α) by colorimetry and radioimmunoassay,as appropriate.We found that STP could inhibit ADP-induced platelet aggregation,and the inhibitory ratio was 91.50% at the STP concentration of 4.0 mg/mL.Furthermore,STP markedly affected AA metabolism by decreasing the synthesis of MDA(P<0.01) and increasing the synthesis of 6-keto-PGF1α,thus changing the plasma TXB2/6-keto-PGF1α balance when the platelets were activated(P<0.01).Therefore,STP altered AA metabolism and these findings partly revealed the molecular mechanism by which STP inhibits ADP-induced platelet aggregation.
文摘Sargassum thunbergii is an economically important brown alga that is used as a perferred food for sea cucumber in China. However, reports on the reproductive biology of S. thunbergii are limited. This study observed the characteristics of mature receptacles. The effects of different temperatures, light intensities, and photoperiods on the egg release of mature S. thunbergii receptacles were investigated. A liquid-phase oxygen electrode system was used to obtain light saturation and light compensation points of egg and young thalli of S. thunbergii. Results showed that temperature was the key factor for the egg release of mature receptacles. The conditions most conducive to egg release were 20°C to 23°C temperature and 50 μmol photons m-2·s-1 to 200 μmol photons m-2·s-1 light intensity. In addition, the light saturation and compensation points of unfertilized eggs or young thalli at 2 d or 3 d postfertilization ranged from 90 μmol photons m-2·s-1 to 120 μmol photons m-2·s-1 and 14 μmol photons m-2·s-1 to 22 μmol photons m-2·s-1, respectively. The combined results provide a reference for the sporeling culture of S. thunbergii.
基金supported by Korea Institute of Marine Science&Technology Promotion(KIMST)funded by the Ministry of Oceans and Fisheries,Korea(20220488)。
文摘Low molecular weight polysaccharides can be isolated from Sargassum thunbergii(LMPST)and in vitro experiments were conducted to evaluate the inhibitory effects on lipids.Two natures of LMPST were attained from S.thunbergii and appraised their LMPST on palmitic acid(PA)induced lipid accretion in Hep G2,and 3T3-L1 cells.LMPST treatment lessened lipid deposition and intracellular free fatty acid and triglyceride intensities in PA-treated above mentioned cells.The mechanistic study publicized that LMPST2 significantly suppressed adipogenesis and stimulated the PA-treated 3T3-L1 cells occupied in the lipolysis pathway.Furthermore,in PA-treated Hep G2 cells,the free fatty acid oxidation was significantly increased by LMPST2.Given these constructive properties of LMPST2 from S.thunbergii,is a potential candidate for diminishing the intracellular lipids,and for a therapeutic agent in those conditions.
基金This work was supported by Public Science and Technology Research Funds Projects of Ocean （Grant No. 201505022）, the National Natural Science Foundation of China NSFC-Shandong Joint Fund （U1406402-5）, the National Natural Science Foundation of China （Grant No. 81671828）, and the Taishan Scholar Program of China.
基金Supported by the National Natural Science Foundation of China （30270258 and 40506028） and Encouraging Foundation for 0utstanding Youth Scien- tists of Shangdong Province （03BS 120）.The authors thank Professor Guangxi Xing for his useful comments on the manuscript and for improving an earlier vision of this paper.
文摘Results of neutron activation analysis (NAA) of Sargassum samples collected from the Qingdao Taipingjiao coast on March 20 , 1996 showed that (1) Sargassumthunbergii can to some extent potassium and calcium (the accumulation coefficientwas 10), (2) it can accumulate all trace elements , especially iron , manganese and zinc,(3) it can accumulate strontium , aluminium thorium , and rare earth elements.
