Screening of Bioactive Materials from Freshwater Microalgae

doi:2004.19.3.271

Algae > Volume 19(3); 2004 > Article

Algae 2004;19(3): 271-276. doi: https://doi.org/10.4490/ALGAE.2004.19.3.271

Wan-Seok Lee, Aeran Choi, Chi-Yong Ahn, Hyuncheol Oh¹, Jong Seog Ahn¹ and Hee-Mock Oh^*

Environmental Biotechnology Laboratory and
¹Laboratory of Cellular Signalling Modulator, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333, Korea

ABSTRACT

One hundred and fifty four micro algal strains, newly isolated from nationwide freshwaters in Korea, were screened for their anticancer, ant diabetic, and antibiotic activities. The micro algal strains were cultured with different nutritional conditions that were divided into 4 groups as follows; a normal Allen medium, nitrogen (N)-limited medium, phosphorus (P)-limited medium, and N and P-limited medium. Algal biomass was extracted with a mixture of acetone:H₂O (1:1, v:v) and the extracts were used for the screening of bioactive materials. Anticancer, ant diabetic, and antibiotic materials were screened by the methods of vaccinia Hl-related protein tyrosine phosphates (VHR DS-PTPase) inhibition, protein tyrosine phosphates 1B (PTP1B) inhibition, and paper disk. The inhibition activity of VHR DS-PTPase was observed in 18 strains, having a maximum 79% inhibition from Anabaena affinis and the inhibition activity of PTP1B was observed in 9 strains, having a maximum 97% from Sphaerocystis schroeteri. Microcystis aeruginosa incubated in an N and P-limited medium showed antibiotic activity in 8 species out of 13 pathogenic bacteria. As a whole, it seemed that the stressed condition such as N and/or P limitation increased the production of bioactive materials in micro algae.

Key words: bioactive materials; microalgae; protein tyrosine phosphatase 1B(PTP1B); vaccinia H1-related protein tyrosine phosphatase(VHR DS-PTPase)