Defatted Rapeseed Meal Research Articles

The Antiproliferative Activity of a Mixture of Peptide and Oligosaccharide Extracts Obtained from Defatted Rapeseed Meal on Breast Cancer Cells and Human Fibroblasts.

Oligosaccharide and peptide extracts obtained separately from defatted rapeseed meal (DRM) have shown antiproliferative activities on the MCF-7 breast cancer cell line. However, oligosaccharide extracts were not tested on human fibroblasts and have low yields. The objective of the present study was to combine two antiproliferative extracts, the peptides and oligosaccharides, that were obtained independently with commercial enzymes from DRM, allowing improvement of the mass yield and antiproliferative activity. The DRM was solubilized in an alkaline medium to obtain an insoluble meal residue (IMR) and an alkaline extract (RAE). To produce the oligosaccharide extract from IMR, three enzymes and different enzyme/substrate ratios were used. The oligosaccharide extract (molecular weight <30 kDa) recovered with the commercial enzyme. Endogalacturonase showed an 80% inhibition on MCF-7 cells at 20 mg/mL. The combination of this oligosaccharide extract with the peptide extract (obtained with Alkalase 2.4 L from a RAE at 10 mg/mL) inhibited 84.3% of MCF-7 cells proliferation at a concentration of 20 mg/mL, exhibiting no cytotoxic effects on fibroblasts. The mass yield of the extract pool was 27.07% (based on initial DRM). It can be concluded that a mixture of antiproliferative extracts was produced from DRM which was selective against MCF-7 cells.

Antiproliferative Rapeseed Defatted Meal Protein and Their Hydrolysates on MCF-7 Breast Cancer Cells and Human Fibroblasts.

Defatted rapeseed meal (DRM) is a sub-valorized agro-industrial by-product, with a high protein content whose peptides could have potential anticancer activity against cancer cell lines. The objective of the present study is to obtain an enzymatic hydrolysate of rapeseed protein that inhibits proliferation on a breast cancer cell line (MCF-7), but not healthy human fibroblast cells. The DRM was solubilized in an alkaline medium to obtain an alkaline rapeseed extract (RAE). Acid precipitation of the proteins contained in RAE recovered a rapeseed protein isolate (RPI). To produce protein hydrolysates, two alkaline protease and different enzyme/substrate ratios were used. All the protein hydrolysates showed antiproliferative activity on MCF-7 cells. However, only the hydrolysate recovered from the enzymatic hydrolysis of RPI (Degree of hydrolysis (DH ) between 8.5 and 9% (DH1)) did not affect human fibroblast cells, inhibiting 83.9% of MCF-7 cells’ proliferation and showing a mass yield of 22.9% (based on the initial DRM). The SDS-PAGE gel revealed that DH1 was composed mainly of 10 kDa peptides and, to a lesser extent, 5 and 2 kDa. It is concluded that DH1 is a promising peptide extract for future research as a putative anti-breast cancer agent.

Spectral properties of sinapine in water environment

In the search for new protein products for human and animal consumption, defatted rapeseed meal has been considered as a potential source of high nutritional value proteins because of its well-balanced amino acid composition. Its use as an animal feed or human food, however, is limited by antinutritive compounds such as sinapine (SNP). SNP is a major phenolic compound of extracted meal flours and creates complexes with albumins. These complexes will be investigated later using spectrophotometric methods. The first step was to establish the spectroscopic properties of SNP in water environments of different pH. The equilibrium of the ionic forms of SNP at pH5.46–10.58 was analyzed using absorption and fluorescence molecular spectroscopy. Equilibrium constants and pKa of the OH group in SNP were calculated in electronic ground and excited states. The absorption spectrum of SNP with a dissociated hydroxyl group was difficult to obtain due to SNP molecule instability in alkaline solutions. Therefore, this spectrum and molar extinction coefficient were calculated using measured spectra in lower pH. Furthermore, the fluorescence spectra and quantum yield for two ionic forms of SNP as well as pKa⁎ in the excited state were determined.

Antihypertensive activity of different protein hydrolysates from defatted rapeseed meal

Antihypertensive activity of different protein hydrolysates from defatted rapeseed meal

INDUCTION OF APOPTOSIS IN CERVIX NEOPLASMS HeLa CELLS BY A RAPESEED PEPTIDE HYDROLYSATE FRACTION

One rapeseed peptide fraction (RSP2) was prepared from rapeseed meal by enzyme digestion and separation on Sephadex gel-filtration column. The anticancer effects of RSP2 on human cervical HeLa cell lines were evaluated. Exposure of RSP2 caused a significant decrease in viability of HeLa cells in a dose-dependent manner and typical morphological changes and apoptosis bleb phenomenon in RSP2-treated HeLa cells were observed. DNA fragmentation assay and single-cell gel electrophoresis showed that RSP2 could induce apoptosis in HeLa cells at all concentrations tested in a dose-dependent manner. Together with our recently published data that RSP2 could decrease the percentage of HeLa cells in the G0/G1phase from 55% to 43%, and increase the ratio of apoptotic cells from 2.9 to 40%, results of this study highlighted the candidacy of RSP2 as a novel source of biologically active peptides with an inhibiting effect on human cancer cells. PRACTICAL APPLICATIONS Apoptosis is an important biological mechanism to maintain the integrity of multicellular organisms and the failure of apoptosis could lead to the development of human malignancies. Rapeseed is the world's second leading source of protein meal and could potentially be used as a food ingredient instead of being wasted or being used for animal feed. In this study, we identified one rapeseed peptide fraction prepared from rapeseed meal as a source of bioactive peptides with anticarcinogenic properties on human cancer cell through the induction of apoptosis. In addition, our previous study showed rapeseed peptide hydrolysate may be useful as a human food addition with antioxidant properties. Therefore, an underutilized by-product such as defatted rapeseed meal could be utilized as novel therapeutic agents to fight against cancer and develop new functional foods.

The lipoxygenase activity of rapeseed

AbstractZero‐erucic rapeseed has both the lipoxygenase‐I and lipoxygenase‐II activities, both of which should be taken into account on storage of seeds. The lipoxygenase‐II activity (the maximum at pH = 6.5–6.8) is lower but the optimum pH is close to that of ground seed (pH = 6.3). The extent of lipoxygenase‐catalyzed oxidation increased in presence of natural rapeseed lipids. The content of conjugated double bonds of lipid hydroperoxides produced as primary reaction products was in close linear relation with the content of total oxidized products determined by HPLC. The content of conjugated double bonds in defatted rapeseed meal containing addition of linoleic acid, linolenic acid, or methyl linoleate, respectively, reached its maximum in 3–6 min. There was great variability among the lipoxygenase activities of different rapeseed samples.

Air classification of rapeseed meal using the tervel separator

AbstractThe University of Toronto Tervel Separator was used to fractionate ground, defatted rapeseed meal into protein enriched, and high‐fibre products suitable for inclusion into food products and feed respectively. The meal was screened into fractions of a narrow range of particle size and classified at air speeds chosen to utilize as much of the collection area of the separator as possible. The meat‐rich and hull‐rich cuts were chosen arbitrarily, the cut point being a compromise between pure meat fraction and the greatest possible yield of the meat‐rich fraction. All meat‐rich samples had an increased protein content compared to the original oil‐free meal (43.1%). The 300/425 μm, 425/600 μm, and 600/850 μm meat‐rich fractions had a protein content (moisture‐, and oil‐free basis) of 54.4%, 55.6% and 49.5%, respectively. These meat‐rich fractions contained 28.7%, 20.9% and 15.3% of the protein present in the feed material for a total protein recovery of 64.9% in approximately 55% of the meat weight. The protein‐rich fraction is competitive with dehulled soya meal on the basis of protein content.

Removal of Glucosinolates from Defatted Rapeseed Meal by Extraction with Aqueous Ethanol

Defatted rapeseed meals containing about 120μM glucosinolates/g were extracted with aqueous ethanol (75%). It was found that the extractability of glucosinolates depended on the history of the meal. From expelled, hexane extracted, toasted meal, the greater part of the glucosinolates could be removed by direct extraction with aqueous ethanol. This procedure incompletely extracted glucosinolates from open air desolventized meals. In that case, an incubation step prior to extraction was needed, involving heating of the meal in the presence of water (2g/g) at 40°C for 1h. The use of mustard seed meal (20mg/g) as a source of myrosinase and L-ascorbic acid (3mg/g) during incubation, proved to be essential for the removal of the glucosinolates from meal with a low endogenous myrosinase activity. Under these conditions, more than 99.5% of glucosinolates could be removed.

Extraction of N‐compounds of rapeseed meal in relation to pH and temperature

AbstractNitrogen compounds were extracted from defatted rapeseed meal with 0–0.1 N aqueous sodium hydroxide or hydrochloric acid. Extractions were carried out for 30 min in water bath at 20, 40, 60, 80 or 100 C. Samples were centrifuged and concentrations of nitrogen and pH were measured. The highest extractability of N‐compounds (more than 80% of total N) was at pH 9.5–10 and 30–45 C. The lowest extractability (20–25% of total N) was at pH 6.5–8, and 80–100 C, the region of heat denaturation, and at pH 3.8–4 at 20 C (35% of total N).