- Email: [email protected]
Response of diatom plasma membrane ATpases to environmental silicon signal
Abstracts / Journal of Biotechnology 136S (2008) S558–S576
algae oil was extracted near completely. The freezing and thawing method could be widely employed in marine algae oil extracting industry.
S569
Technology for Aquaculture and Food Safety, Fujian Province University (no. 2007J104). References
References Bligh, E.G., Dyer, W.J., 1959. A rapid method lipid extraction and purification. C. J. Biochem. Physiol. 37, 911–923. Chen, Y.Q., 2002. Technology and Method of Biochemical Experiments. Science Press. Hamm, W., Hamilton, R.J., 2000. Edible Oil Processing. Sheffield Academic Press. Mao, S.T., 2008. Shallowly discussed the Chinese native medicine chemical composition withdraws, the separation and the appraisal method. World Health Digest. 5 (1), 101–102. Wen, S.H., Wang, C.H., Ju, B., 1999. Studies on lipids in different kind cell of PorPhyridium cruentum. Chinese J. Marine Drugs 02, 28–31. Wu, S.Q., Yao, R.H., 1994. Study of microbial polyunsaturated fatty acids. 4, 5–8. Wu, G.X., Zhang, Q.C., 1995. Resource utilization of highunsaturated fatty acids. 7 (1), 57–60.
Mark, H., 2003. Biological processing of nanostructured silica in diatoms. Prog. Org. Coatings 47, 256–266. Virginia, A.E, John, A.B., Chris, B., et al., 2004. The genome of the diatom Thalassiosira Pseudonana: ecology, evolution, and metabolism. Science 306, 79–86.
doi:10.1016/j.jbiotec.2008.07.1341 VI4-P-033 Optimization and scale-up of a new agar extraction from red seaweed Haiyan Li 1,2,∗ , Wei Zhang 1,3
doi:10.1016/j.jbiotec.2008.07.1340 VI4-P-032 Response of diatom plasma membrane ATpases to environmental silicon signal Jiang Zheng 1,3,∗ , Junrong Liang 2 , Yahui Gao 2 , Chong Li 1 1
College of Oceanography and Environmental Science, Xiamen University, Xiamen 361005, China 2 Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen 361005, China 3 Fisheries College of Jimei University, Xiamen 361021, China E-mail addresses: [email protected] (J. Zheng), [email protected] (J. Liang). Diatom cell wall contains nanostructured silica with features exceeding current manufacturing capabilities, reproduced with exactness in vast numbers (Mark, 2003). Although the genes encoding silicic acid transporters (SITs) have been found (Virginia et al., 2004), most of its regulation mechanism are still unknown to us, especially the response mechanism to the environmental silicon signal. In the present paper, its response mechanism was studied from the view of plasma membrane ATPase. Experimental material diatom Ditylum brightwelli (West) Grunow was cultivated for 5 days, under the environment of low silicon concentration of 6 mg/L, high silicon concentration of 150 mg/L and normal silicon concentration of 30 mg/L (control) respectively. Then the plasma membrane vesicles of the diatom was extracted and purified by two-phase method. After measuring the Na+ /K+ -ATPase, Ca2+ /Mg2+ -ATPase and total ATPase activities of the plasma membrane, the results showed that the ATPases responded differently to the different environmental silicon concentrations. In the high silicon environment, the total ATPase activity of the diatom plasma membrane was significantly higher than that of the control (P < 0.05), while the Na+/K+-ATPase activity was remarkably lower than that of the control in the low silicon environment (P < 0.01); but the Ca2+ /Mg2+ -ATPase activity did not change remarkably in either high or low silicon environment. These results showed that the diatom plasma membrane ATPases and their activities had a close relationship with the environmental silicon content, and was able to be a responding indicator of diatom to the environmental silicon signal. Acknowledgements The project was supported by the National Natural Science Foundation (no. 40676082) and Open Fund of Key Lab of Science and
1
Marine Bioproducts Engineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China 2 Graduate School of the Chinese Academy of Sciences, Beijing 10089, China 3 Molecular Bioprocessing and Bioproducts Laboratory, Department of Medical Biotechnology, Flinders University, Adelaide, SA 5042 Australia E-mail address: [email protected] (W. Zhang). The commercial mariculture of Gracilaria lemaneiformis has been leading in China, because of their fast growing ability, higher adaptability, uses as aquaculture-bioremediator and for the higher concentration of agar–agar (Zhou et al., 2006). Besides food and agar-industry, the abundant availability of cultured algae needs other potential and more prospective markets. An eco-friendly photobleaching extraction process for the agar extraction from the red algae Gracilaria lemaneiformis was developed for the benefit of workers’ health and environmental safety (Li et al., 2008). The current study reported the optimization of key process parameters (alkali modification concentration, photobleaching duration, algal length and screen filter opening size) in order to scale up this new technique. And a 20 L agar extraction reactor was thus constructed and the scale-up of this agar extraction process was tested in six-batch experiments. The optimal conditions were found to be modification by 3–5% NaOH, photobleaching for 5 h, using 2–4 cm length of algae and the 6 m opening filter screen. The resulted agar quality was similar to that of the laboratory-scale extraction. In addition, batch-to-batch reproducibility was excellent. The agar yield and gel strength for 5% NaOH modified agar were 26.8% and 1897 g cm−2 , while those for 3% NaOH modified agar were 28.2% and 1287 g cm−2 , respectively. The results demonstrate excellent scale-up ability and potential application of this new photobleaching agar extraction process at commercial scale. And it is clear that the agar yield and quality can be manipulated through the alkali modification in this new eco-friendly extraction as per the market demands. References Li, H.Y., Yu, X.J., Jin, Y., Zhang, W., Liu, Y.L., 2008. Development of an eco-friendly agar extraction technique from the red seaweed Gracilaria lemaneiformis. Bioresour. Technol. 99, 3301–3305. Zhou, Y., Yang, H.S., Hu, H.Y., 2006. Bioremediation potential of the macroalga Gracilaria lemaneiformis (Rhodophyta) integrated into fed fish culture in coastal waters of north China. Aquaculture 252, 264–276.
doi:10.1016/j.jbiotec.2008.07.1342
algae oil was extracted near completely. The freezing and thawing method could be widely employed in marine algae oil extracting industry.
S569
Technology for Aquaculture and Food Safety, Fujian Province University (no. 2007J104). References
References Bligh, E.G., Dyer, W.J., 1959. A rapid method lipid extraction and purification. C. J. Biochem. Physiol. 37, 911–923. Chen, Y.Q., 2002. Technology and Method of Biochemical Experiments. Science Press. Hamm, W., Hamilton, R.J., 2000. Edible Oil Processing. Sheffield Academic Press. Mao, S.T., 2008. Shallowly discussed the Chinese native medicine chemical composition withdraws, the separation and the appraisal method. World Health Digest. 5 (1), 101–102. Wen, S.H., Wang, C.H., Ju, B., 1999. Studies on lipids in different kind cell of PorPhyridium cruentum. Chinese J. Marine Drugs 02, 28–31. Wu, S.Q., Yao, R.H., 1994. Study of microbial polyunsaturated fatty acids. 4, 5–8. Wu, G.X., Zhang, Q.C., 1995. Resource utilization of highunsaturated fatty acids. 7 (1), 57–60.
Mark, H., 2003. Biological processing of nanostructured silica in diatoms. Prog. Org. Coatings 47, 256–266. Virginia, A.E, John, A.B., Chris, B., et al., 2004. The genome of the diatom Thalassiosira Pseudonana: ecology, evolution, and metabolism. Science 306, 79–86.
doi:10.1016/j.jbiotec.2008.07.1341 VI4-P-033 Optimization and scale-up of a new agar extraction from red seaweed Haiyan Li 1,2,∗ , Wei Zhang 1,3
doi:10.1016/j.jbiotec.2008.07.1340 VI4-P-032 Response of diatom plasma membrane ATpases to environmental silicon signal Jiang Zheng 1,3,∗ , Junrong Liang 2 , Yahui Gao 2 , Chong Li 1 1
College of Oceanography and Environmental Science, Xiamen University, Xiamen 361005, China 2 Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen 361005, China 3 Fisheries College of Jimei University, Xiamen 361021, China E-mail addresses: [email protected] (J. Zheng), [email protected] (J. Liang). Diatom cell wall contains nanostructured silica with features exceeding current manufacturing capabilities, reproduced with exactness in vast numbers (Mark, 2003). Although the genes encoding silicic acid transporters (SITs) have been found (Virginia et al., 2004), most of its regulation mechanism are still unknown to us, especially the response mechanism to the environmental silicon signal. In the present paper, its response mechanism was studied from the view of plasma membrane ATPase. Experimental material diatom Ditylum brightwelli (West) Grunow was cultivated for 5 days, under the environment of low silicon concentration of 6 mg/L, high silicon concentration of 150 mg/L and normal silicon concentration of 30 mg/L (control) respectively. Then the plasma membrane vesicles of the diatom was extracted and purified by two-phase method. After measuring the Na+ /K+ -ATPase, Ca2+ /Mg2+ -ATPase and total ATPase activities of the plasma membrane, the results showed that the ATPases responded differently to the different environmental silicon concentrations. In the high silicon environment, the total ATPase activity of the diatom plasma membrane was significantly higher than that of the control (P < 0.05), while the Na+/K+-ATPase activity was remarkably lower than that of the control in the low silicon environment (P < 0.01); but the Ca2+ /Mg2+ -ATPase activity did not change remarkably in either high or low silicon environment. These results showed that the diatom plasma membrane ATPases and their activities had a close relationship with the environmental silicon content, and was able to be a responding indicator of diatom to the environmental silicon signal. Acknowledgements The project was supported by the National Natural Science Foundation (no. 40676082) and Open Fund of Key Lab of Science and
1
Marine Bioproducts Engineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China 2 Graduate School of the Chinese Academy of Sciences, Beijing 10089, China 3 Molecular Bioprocessing and Bioproducts Laboratory, Department of Medical Biotechnology, Flinders University, Adelaide, SA 5042 Australia E-mail address: [email protected] (W. Zhang). The commercial mariculture of Gracilaria lemaneiformis has been leading in China, because of their fast growing ability, higher adaptability, uses as aquaculture-bioremediator and for the higher concentration of agar–agar (Zhou et al., 2006). Besides food and agar-industry, the abundant availability of cultured algae needs other potential and more prospective markets. An eco-friendly photobleaching extraction process for the agar extraction from the red algae Gracilaria lemaneiformis was developed for the benefit of workers’ health and environmental safety (Li et al., 2008). The current study reported the optimization of key process parameters (alkali modification concentration, photobleaching duration, algal length and screen filter opening size) in order to scale up this new technique. And a 20 L agar extraction reactor was thus constructed and the scale-up of this agar extraction process was tested in six-batch experiments. The optimal conditions were found to be modification by 3–5% NaOH, photobleaching for 5 h, using 2–4 cm length of algae and the 6 m opening filter screen. The resulted agar quality was similar to that of the laboratory-scale extraction. In addition, batch-to-batch reproducibility was excellent. The agar yield and gel strength for 5% NaOH modified agar were 26.8% and 1897 g cm−2 , while those for 3% NaOH modified agar were 28.2% and 1287 g cm−2 , respectively. The results demonstrate excellent scale-up ability and potential application of this new photobleaching agar extraction process at commercial scale. And it is clear that the agar yield and quality can be manipulated through the alkali modification in this new eco-friendly extraction as per the market demands. References Li, H.Y., Yu, X.J., Jin, Y., Zhang, W., Liu, Y.L., 2008. Development of an eco-friendly agar extraction technique from the red seaweed Gracilaria lemaneiformis. Bioresour. Technol. 99, 3301–3305. Zhou, Y., Yang, H.S., Hu, H.Y., 2006. Bioremediation potential of the macroalga Gracilaria lemaneiformis (Rhodophyta) integrated into fed fish culture in coastal waters of north China. Aquaculture 252, 264–276.
doi:10.1016/j.jbiotec.2008.07.1342