Dietary polyunsaturated fatty acids （PUFAs）, which are abundant in marine fish oils, have recently received global attention for their prominent anti-obesogenic effects. Among PUFAs, eicosapentaenoic acid （EPA; 20...Dietary polyunsaturated fatty acids （PUFAs）, which are abundant in marine fish oils, have recently received global attention for their prominent anti-obesogenic effects. Among PUFAs, eicosapentaenoic acid （EPA; 20：5n-3） and docosahexaenoic acid （DHA; 22：6n-3）, which are n-3 long-chain PUFAs widely referred to as omega-3 oils, were reported to prevent the development of obesity in rodents and humans. In the present study, we evaluated the anti-obesity effects of microalgal oil on high-fat induced obese C57BL/6 mice, compared with commercial omega-3 fish oil and vegetable corn oil. Microalgal oil is an inherent mixture of several PUFAs, including EPA, DHA and other fatty acids produced from a marine microalgal strain of Thraustochytriidae sp. derived mutant. It was found to contain more PUFAs （〉80%） and more omega-3 oils than commercial omega-3 fish oil （PUFAs 〉31%） and corn oil （PUFAs 59%）. All three types of oils induced weight loss in high-fat-induced obese mice, with the loss induced by microalgal oil being most significant at 9 weeks （10% reduction）. However, the oils tested did not improve blood lipid levels, although microalgal oil showed an apparent inhibitory effect on lipid accumulation in the liver. These findings may be attributed to the higher PUFA content, including omega-3 oils of microalgal oil than other oils. Collectively, these findings suggest that microalgal oil, derived from Thraustochytriidae sp. derived mutant, is a prominent candidate for replacement of omega-3 fish oils based on its apparent anti-obesity effect in vivo.展开更多
The present study investigated quantitatively the significance of HNLC (high-nutrient low-chlorophyll) regions and its grazing control with the improved iron fertilization for climate change. The limitation of iron (F...The present study investigated quantitatively the significance of HNLC (high-nutrient low-chlorophyll) regions and its grazing control with the improved iron fertilization for climate change. The limitation of iron (Fe) for phytoplankton growth in HNLC regions was confirmed by sulfur compounds (S) such as volcanic ash and hydrogen sulfide (H2S) in batch cultures, whose chemical sediment of Fe3S4 showed 4.06 wt%. The technologies developed for iron fertilization since 1993 till now were not practical to provide sufficient amounts of bioavailable iron due to sedimentary iron sulfides induced by undersea volcanic sulfur compounds. The proposed technology for iron fertilization was improved to enhance the bioavailable iron to phytoplankton by keeping minimal sulfur compounds in HNLC regions. The low productivity of phytoplankton by grazing control in HNLC regions was 6% diatoms whose 52% was grazed by copepods and 42% by krill on the basis of data analysis in 2000 EisenEx Experiment at boundary of Antarctic and African tectonic plates. All of the previous iron fertilization experiments were conducted at volcanic sulfur compounds enriched HNLC regions. The present study revealed that the enhanced phytoplankton productivity in batch culture without sedimentary iron sulfides can be possible only if sulfur compounds are minimal, as is in Shag Rocks (53°S, 42°W) of South Georgia in Scotia Sea in the Southern Ocean.展开更多
基金supported by a grant from the KRIBB Research Initiative Program(KGM2211531)supported by Priority Research Centers Program through NRF funded by the Ministry of Education,Science and Technology (2015R1A6A1A04020885)
文摘Dietary polyunsaturated fatty acids （PUFAs）, which are abundant in marine fish oils, have recently received global attention for their prominent anti-obesogenic effects. Among PUFAs, eicosapentaenoic acid （EPA; 20：5n-3） and docosahexaenoic acid （DHA; 22：6n-3）, which are n-3 long-chain PUFAs widely referred to as omega-3 oils, were reported to prevent the development of obesity in rodents and humans. In the present study, we evaluated the anti-obesity effects of microalgal oil on high-fat induced obese C57BL/6 mice, compared with commercial omega-3 fish oil and vegetable corn oil. Microalgal oil is an inherent mixture of several PUFAs, including EPA, DHA and other fatty acids produced from a marine microalgal strain of Thraustochytriidae sp. derived mutant. It was found to contain more PUFAs （〉80%） and more omega-3 oils than commercial omega-3 fish oil （PUFAs 〉31%） and corn oil （PUFAs 59%）. All three types of oils induced weight loss in high-fat-induced obese mice, with the loss induced by microalgal oil being most significant at 9 weeks （10% reduction）. However, the oils tested did not improve blood lipid levels, although microalgal oil showed an apparent inhibitory effect on lipid accumulation in the liver. These findings may be attributed to the higher PUFA content, including omega-3 oils of microalgal oil than other oils. Collectively, these findings suggest that microalgal oil, derived from Thraustochytriidae sp. derived mutant, is a prominent candidate for replacement of omega-3 fish oils based on its apparent anti-obesity effect in vivo.
文摘The present study investigated quantitatively the significance of HNLC (high-nutrient low-chlorophyll) regions and its grazing control with the improved iron fertilization for climate change. The limitation of iron (Fe) for phytoplankton growth in HNLC regions was confirmed by sulfur compounds (S) such as volcanic ash and hydrogen sulfide (H2S) in batch cultures, whose chemical sediment of Fe3S4 showed 4.06 wt%. The technologies developed for iron fertilization since 1993 till now were not practical to provide sufficient amounts of bioavailable iron due to sedimentary iron sulfides induced by undersea volcanic sulfur compounds. The proposed technology for iron fertilization was improved to enhance the bioavailable iron to phytoplankton by keeping minimal sulfur compounds in HNLC regions. The low productivity of phytoplankton by grazing control in HNLC regions was 6% diatoms whose 52% was grazed by copepods and 42% by krill on the basis of data analysis in 2000 EisenEx Experiment at boundary of Antarctic and African tectonic plates. All of the previous iron fertilization experiments were conducted at volcanic sulfur compounds enriched HNLC regions. The present study revealed that the enhanced phytoplankton productivity in batch culture without sedimentary iron sulfides can be possible only if sulfur compounds are minimal, as is in Shag Rocks (53°S, 42°W) of South Georgia in Scotia Sea in the Southern Ocean.
