Oilseed cakes and meals are obtained as by-products after oil extraction. They contain 15–60 % proteins with a relatively good amino acid proportion and other valuable components such as dietary fibre, residual fat, polyphenols etc. Proteins are above all represented by globulins, especially 11-12S globulin, and albumins. Oilseed cakes are often used as feed for farm animals but they can be valorised in the form of flour and protein concentrate or by an isolation using dry or wet processes. In this work, a characterization of seed proteins of selected oilseed crops and methods of protein isolation are presented. Possibilities of oilseed protein products use in human nutrition and food products are evaluated.
Proteins were obtained from effluent of a starch manufacture by using different isolation temperatures (40, 60, 80, and 100 °C). The proteins, remaining in effluent after treatment of potato juice at 80 and 100 °C differed significantly in composition and in structural stability as well as in trypsin inhibitory and antifungal activities in comparison with the variants of 40 and 60 °C. The protein samples of 80 °C exhibited the highest antifungal activity and its average value of IC50 against five strains of two Fusarium species was determined in average at 0.18 mg ml-1. The 80 °C protein samples consisted predominantly of low-molecular proteins (7-17 kDa) identified as potato tuber protease inhibitors I and II. Predominantly, protease inhibitors II were identified for the protein samples obtained by 100 °C and here we identified 7 spots in comparison with 12 identified for the 80 °C samples. Samples of 40 and 60 °C with low antifungal activities represent high variability of detected and identified proteins. We identified various representatives of aspartic, cysteine, and serine protease inhibitors in both types of samples. These samples also contained Kunitz-type protease inhibitors that were not found in the 80 and 100 °C samples which documented thermal unstableness of Kunitz-type protease inhibitors. Functional stability at high temperatures and antifungal activity of isolated potato protease inhibitors I and II support the potential of this fraction usage in food, feed, pharmaceutical, or agricultural industry and offer new products for starch manufactures. At the same time, utilization of the stable protein fraction of waste deproteinized potato water promotes exploitation of potato starch production resources.
- MeSH
- 2D gelová elektroforéza MeSH
- antifungální látky farmakologie MeSH
- Fusarium účinky léků MeSH
- hlízy rostlin chemie MeSH
- mikrobiální testy citlivosti MeSH
- proteomika MeSH
- rostlinné proteiny chemie izolace a purifikace farmakologie MeSH
- škrob MeSH
- Solanum tuberosum chemie MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
- stabilita proteinů MeSH
- tandemová hmotnostní spektrometrie MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
