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Composition of tomatoes and tomato products in antioxidants (WG1) page 79
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For plasma and serum, lipid soluble vitamins and carotenoids were usually extracted
after protein precipitation by ethanol, by an organic solvent such as hexane. The extraction
was improved if the plasma had been previously diluted by a same volume of water or
physiologic buffer (Fig. 18) (Aebisher et al.1999).
1
0,8
0,6
0,4
0,2
0
Fig 18. Effect of water addition in plasma on retinol, α-tocopherol and carotenoid
(From Aebisher et al; 1999)
extraction efficiency.
Normalized amount of extracted lycopene
0 1 2 3 4 5
Ratioofwateraddedtoplasma
In several studies, magnesium carbonate was initially added combined with the
biological material (Scott 1992, Taungbodhitham et al. 1998, Tonucci et al. 1995). The best
extraction yields were obtained when carbonate/solvent ratios were between 1/1 and 1/2