In this study, we evaluated the anti-proliferative activity of phlorotannins derived from brown algae Laminariajaponica Aresch extracts on the human hepatocellular carcinoma cell （BEL-7402） and on routine leukemic c...In this study, we evaluated the anti-proliferative activity of phlorotannins derived from brown algae Laminariajaponica Aresch extracts on the human hepatocellular carcinoma cell （BEL-7402） and on routine leukemic cells （P388） by MTT assay. Cells were incubated with 100 μg/mL of the phlorotannin extract （PE） for 48 h. The inhibitory rate of PE on BEL-7402 and P388 cells was 30.20±1.16% and 43.44±1.86%, respectively, and the half-inhibitory concentration of PE （IC50） on P388 and BEL-7402 cells was 120 μg/mL and 〉200 μg/mL, respectively. Microscopic observation shows that the morphologic features of tumor cells treated with PE and 5-fluorouracil are markedly different from the normal control group. The inhibitory rate of fraction A2 isolated from PE by sephadex LH-20 for BEL-7402 and P388 cells at the sample concentration of 70.42 μg/mL was 61.96±7.02% and 40.47±8.70%, respectively. The apoptosis peak for fraction A2 was the most profound of all fractions used in the flow cytometry assay. The results indicate that the anti-proliferative of this algal extract is associated with the total phlorotannin content.展开更多
Phaeodactylum tricornutum is one of the important marine diatoms for oceanic primary production. Its reproduction has profound significance in the life cycle; however, the nuclear behavior during its sexual reproducti...Phaeodactylum tricornutum is one of the important marine diatoms for oceanic primary production. Its reproduction has profound significance in the life cycle; however, the nuclear behavior during its sexual reproduction was not clear. In this study, we observed the nuclear transition and determined its correlation with cell conjunction. It was found that two cells jointed at their apices first and swung and aligned each other immediately, and nucleus from one cell was able to transfer into another one during cell conjugation. The cell pairs conjugated for nuclear transition were different from those formed in mitosis in hypovalve thickness and cellular arrangement. Our findings proved the existence of sexual reproduction in P. tricornutum.展开更多
Silvetia babingtonii is a potentially economic brown alga for sources of food and high-value added utilization. So far, sporeling nursery and field cultivation has not been successful. The lack of knowledge on develop...Silvetia babingtonii is a potentially economic brown alga for sources of food and high-value added utilization. So far, sporeling nursery and field cultivation has not been successful. The lack of knowledge on development and life cycle of this alga hinder the development of techniques for the sporeings and cultivation. In this study, internal structure of oogonium and antherium of S. babingtonii was observed with hematoxylin and eosin staining and through microscope. Meanwhile, early development from zygotes to juvenile sporelings was studied at 20℃ under 60–100 μmol photons m-2 s-1. Zygotes germinated and divided into thallus and rhizoid cells. The larger thallus cells further divided and developed into juvenile sporelings; while the smaller rhizoid cells divided and elongated into rhizoid hairs. These findings documented the life cycle of S. babingtonii and provided fundamental knowledge for sporeling nursery in the near future.展开更多
基金Supported by the National Key Technology Research & Development Program of the 11th Five Year Plan of China (No. 2006BAD30B01)the National Natural Science Foundation of China (No. 30871945)
文摘In this study, we evaluated the anti-proliferative activity of phlorotannins derived from brown algae Laminariajaponica Aresch extracts on the human hepatocellular carcinoma cell （BEL-7402） and on routine leukemic cells （P388） by MTT assay. Cells were incubated with 100 μg/mL of the phlorotannin extract （PE） for 48 h. The inhibitory rate of PE on BEL-7402 and P388 cells was 30.20±1.16% and 43.44±1.86%, respectively, and the half-inhibitory concentration of PE （IC50） on P388 and BEL-7402 cells was 120 μg/mL and 〉200 μg/mL, respectively. Microscopic observation shows that the morphologic features of tumor cells treated with PE and 5-fluorouracil are markedly different from the normal control group. The inhibitory rate of fraction A2 isolated from PE by sephadex LH-20 for BEL-7402 and P388 cells at the sample concentration of 70.42 μg/mL was 61.96±7.02% and 40.47±8.70%, respectively. The apoptosis peak for fraction A2 was the most profound of all fractions used in the flow cytometry assay. The results indicate that the anti-proliferative of this algal extract is associated with the total phlorotannin content.
基金supported by the State Basic Research and Development Program of China (973 Program) (2011-CB200901)the Promotive Research Fund for Excellent Young and Middle-aged Scientists of Shandong Province(BS2010SW037)the Opening Research Project of Experimental Marine Biology Laboratory,Institute of Oceanology,Chinese Academy of Sciences
文摘Phaeodactylum tricornutum is one of the important marine diatoms for oceanic primary production. Its reproduction has profound significance in the life cycle; however, the nuclear behavior during its sexual reproduction was not clear. In this study, we observed the nuclear transition and determined its correlation with cell conjunction. It was found that two cells jointed at their apices first and swung and aligned each other immediately, and nucleus from one cell was able to transfer into another one during cell conjugation. The cell pairs conjugated for nuclear transition were different from those formed in mitosis in hypovalve thickness and cellular arrangement. Our findings proved the existence of sexual reproduction in P. tricornutum.
基金sponsored by the Shandong Agricultural Seedstock Breeding Projectthe Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education of China (No. 2010-1561)
文摘Silvetia babingtonii is a potentially economic brown alga for sources of food and high-value added utilization. So far, sporeling nursery and field cultivation has not been successful. The lack of knowledge on development and life cycle of this alga hinder the development of techniques for the sporeings and cultivation. In this study, internal structure of oogonium and antherium of S. babingtonii was observed with hematoxylin and eosin staining and through microscope. Meanwhile, early development from zygotes to juvenile sporelings was studied at 20℃ under 60–100 μmol photons m-2 s-1. Zygotes germinated and divided into thallus and rhizoid cells. The larger thallus cells further divided and developed into juvenile sporelings; while the smaller rhizoid cells divided and elongated into rhizoid hairs. These findings documented the life cycle of S. babingtonii and provided fundamental knowledge for sporeling nursery in the near future.
