Full Length Research Paper

Isolation and partial purification of lysozyme from saliva of Bali cattle (Bos sondaicus) using an aqueous mixture of polyethylene glycol (PEG) with sodium sulfate

Sulaiman Ngongu Depamede^1,3*, Niken Asri², Nur Indah Julisaniah²,

 Bambang F. Suryadi², and Djoko Kisworo¹

¹Microbiology and Biotechnology Laboratory, Faculty of Animal Sciences, University of Mataram, Jalan Majapahit No. 62, Mataram 83125, Indonesia.

²Faculty of Mathematics and Life Sciences, Mataram University, Jl. Majapahit No. 62 Mataram 83125, Indonesia.

³Immunobiology Laboratory, Faculty of Medicine, University of Mataram, Mataram, Indonesia.

*Corresponding author. E-mail: sulaiman_n@unram.ac.id.

Abbreviations: PEG, polyethylene glycol; ddW, double distillated water; SDS-PAGE, sodium dodecyl sulfate polyacrylamide gel electrophoresis.

Accepted 31 October, 2011

   Abstract

Lysozyme from saliva of Bali cattle (Bos sondaicus) was successfully isolated through an aqueous mixture system of polyethylene glycol (PEG 4000) and salt (Na₂SO₄). About 100 µg/ml lysozyme of 14.2 kDa, determined through sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), per 4800 µg/ml saliva was obtained. Based on turbidity assay of Staphylococcus aureus, it was revealed that inhibition activities of 40 µg/ml isolated lysozyme were comparable to 800 µg/ml of a commercial hen egg white lysozyme.

Key words: Lysozyme, Bali cattle, Bos sondaicus, PEG, aqueous mixture system.