Full Length Research Paper

Use of psyllium (isubgol) husk as an alternative gelling agent for the culture of prokaryotic microalgae (Cyanobacteria) Chroococcus limneticus Lemmermann and eukaryotic green microalgae (Chlorophyta) Scenedesmus quadricauda (Turpin) Brebisson

Tahir Atici¹, Khalid Mahmood Khawar²*, Cigdem Alev Ozel¹, Hikmet Katircioglu¹ and Mevlude Alev Ates¹

¹Department of Biology Education, Faculty of Education, Gazi University, Teknikokullar, Ankara, Turkey.

²Department of Field crops, Faculty of Agriculture, University of Ankara, Turkey.

*Corresponding author. E-mail: kmkhawar@gmail.com. 

Abbreviation: kPa, Kilopascal.

Accepted 7 March, 2008

Agar is popularly used as gelling agent to obtain in vitro culture of prokaryotic and eukaryotic microalgae. Exclusive use of agar is resulting in over exploitation of its resources and makes it essential to look for alternative and cheap sources. The study reports in vitro culture of prokaryotic microalgae (Cyanobacteria) Chroococcus limneticus and eukaryotic green microalgae (Chlorophyta) Scenedesmus quadricauda on BG11 medium solidified with 15 g L^-1 agar or 10, 15, 20, 25, 30, 35 and 40 g L^-1 psyllium (isubgol) husk as gelling agent. The results demonstrated that prokaryotic microalgae C. limneticus was less appropriate for culture on psyllium husk gel compared to eukaryotic green microalgae S. quadricauda. However, the cells of C. limneticus could be multiplied on 10 or 15 g L^-1 psyllium husk as gelling agent. The highest number of 642000 cells mL^-1 of C. limneticus on 15 g L^-1 psyllium husk were far lower than 722000 cells mL^-1 on agar gelled medium (control). Contrarily, the cells of S. quadricauda could be multiplied on all concentrations of psyllium husk. Compared to the highest number of 546000 cells mL^-1 of S. quadricauda on 15 g L^-1 agar (control), the highest number of 538000 cells mL^-1 was recorded on 15 g L^-1 psyllium husk gel. The results indicated very similar and comparable cell multiplication behavior of S. quadricauda on agar or 15 g L^-1 psyllium husk and demonstrate the advantage of the very cheap alternative gelling agent psyllium husk over expensive agar for possible use in analytic experiments pertaining to eukaryotic green microalgae.

Key words: Agar-gelled medium, in vitro, psyllium husk gelled medium, viscosity.