DOI : https://doi.org/10.4490/algae.2006.21.4.479

Algae. 2006; 21(4): 479-483.

doi: https://doi.org/10.4490/algae.2006.21.4.479

Ultrastructures of Ptilota filicina (Rhodophyta) by High Pressure Freezing (HPF): Comparison of HPF Fixation and Chemical Fixation

Sang-Hee Lee^1*, Youn-Joong Kim¹, Jong-Man Jeong¹, Jin-Gyu Kim¹, Young-Min Kim¹, Hee-Seok Kweon¹, Won-Jin Moon² and Seok-Hoon Lee¹

¹Division of Electron Microscopic Research, Korea
Basic Science Institute, Daejeon 305-333, Korea
²KBSI, Gwang-ju Center, Gwangju 500-757, Korea

In preparation of the biological samples for electron microscopy, the chemical fixation by glutaraldehyde, paraformaldehyde, and OsO4 has been generally used for a long time. However, the chemical fixation method has some problems: the infiltration time is a little bit long and the ultrastructure of cell or tissue transforms before complete fixation of sample. So, recently, cryo-fixation is considered more often in biomedical field. In this study, we compared High Pressure Freezing (HPF) method with chemical fixation method using a algal sample (Ptilota filicina J. Agardh), which was difficult to fix using chemical fixation method. In chloroplast, the ultrastructure of thylakoid lamella and phycobilisome can not show clearly by chemical fixation. In this study we could observe the ultrastructure of thylakoid lamella and phycobilisome of chloroplast very clearly using HPF fixation. An improved images of ultrastructures of nucleus, mitochondrion and floridean starch could obtain. These results suggest that HPF method is very useful method in algal specimen for electron microscopy.

Keywords : freeze substitution, High Pressure Freezing, Ptilota filicina