DNA extraction

[adamson]

I am working on DNA extraction on 200 mg bovine meat.
I perform microwave the raw meat, add TE buffer 200ul , and 500ul add 10% Chelex100 solution , and boil for 30 minutes at 95C, vortex, centrifuge, collect supernatant , and read at nanodrop spectro.
the nanodrop reading show high in 260nm, but also show high in 230, and 280nm
260nm 1.87abs, 280 1.5 abs, and 230 1.4abs.
can any body suggest addition step to make 230 and 280 lower the sugar, or phenolic compound.
I try to get away fom phenol extraction because 280nm interference.
ideally 260/280 must be 1.7 to 2.1, and 230/260 must be 0.5 to 0.8
I even try add hexane extraction after TE buffer 200ul, but the number is not affecting. may be just remove fat only.
can some body have some suggestion??

[Kneeanderthal]

Try adding 1/3 100% isopropanol after collecting the supernant to precipitate the DNA then spin it down (14,000 rpm for 15 min). Then wash the pellet with cold ethanol, remove the ethanol and let it air dry for 2-3 hours. Resuspend in TE buffer and read A260.