3. FOOD ChEMISTRy & bIOTEChNOLOGy 3.1. Lectures

Chem. Listy, 102, s265–s1311 (2008) Food Chemistry & Biotechnology
rile water, and resuspended in 1 ml of lysis buffer with lysozyme
and treated with laboratory temperature (see above).
Then, the procedure of DnA isolation using magnetic microspheres
was used (see above). In PCR 1 and 3 µl of DnA
matrix were used. The results with 3 µl of DnA matrix are
shown in Fig. 1. In all samples prepared from 3 ml of filtrate,
PCR products specific to Lactococcus lactis were amplified.
Fig. 1. Agarose gel electrophoresis of PCR products obtained
after amplification of lactococcus lactis DNA (3 µl) isolated from
hard cheese samples by magnetic microspheres. Lanes 1-10:
hard cheese samples, lane 11: DNA standards (100 bp ladder),
lane 12: negative control without DNA, lane 13: positive control
with purified lactococcus lactis subsp. lactis CCM 1877T DNA
(c DNA = 10 ng μl –1 )
s792
Conclusion
The evaluated procedure of hard cheese sample preparation
for DnA isolation using magnetic microspheres was
verified on 10 different cheese samples with success. The quick
and more simple method of DnA isolation with magnetic
microspheres gave results comparable to those with DnA
isolated using phenol extraction.
The financial support of the National Grant Agency for
Agricultural Research (NAZV) grant No. 1G 57053 and a
long-term research programme of the Ministry of Education,
Youth, and Sports of the Czech Republic (MSM 0021622415)
are gratefully acknowledged. We thank Mr. Ladislav Červený
for his kind language revision.
REFEREnCES
1. Buist G., Kok J., Leenhouts K.J., Dabrowska M.,
Venema G., Haandrikman A.J.: J. Bacteriol. 177, 1554
(1995).
2. Barakat R.K., Griffiths M.W., Harris L.J.: Int. J. Food
Microbiol. 62, 83 (2000).
3. Burdychova R., Komprda T.: FEMS Microbiol. Lett.
276, 149 (2007).
4. Rittich B., Španová A., Horák D., Beneš M.J., Klesnilová
L., Petrová K., Rybnikář A.: Colloids Surf. B: Biointerfaces
52, 143 (2006).
5. Španová A., Rittich B., Štyriak I., Štyriaková I., Horák
D.: J. Chromatogr. A 1130, 115 (2006).
6. Španová A., Horák D., Soudková E., Rittich B.: J. Chromatogr.
B 800, 27 (2004).
7. Sambrook J., Russel D.W.: Molecular Cloning (3rd ed.),
Cold Spring Harbor Laboratory Press, new York, 2001.