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Summary Background Allergy to sesame seeds is often associated with particularly severe reactions, with a high risk of anaphylaxis. The increase in reports of allergic reactions to sesame is probably due to the growing use of sesame seeds or sesame oil in food. Objective To determine the molecular weights of the proteins in three variety of sesame seeds and to study the isoelectric points and the allergenicity of white sesame proteins. Methods Extracts of white, brown and black sesame seeds were prepared. The white sesame extract, mostly used in bakery, was run on SDS-PAGE and two dimensional electrophoresis. Six sera from patients sensitized or symptomatic to sesame seed were used for Western blotting. Results The protein patterns of the white, brown and black sesame extracts showed major quantitative differences. The white extract had the higher protein concentration and contained 15 proteins of 12–79 kDa, some of them having several acidic isoelectric points. The lowest isoelectric point was 4.9 and the highest was 6.4, giving 35 isoforms. Ten of the 15 proteins (12–57.5 kDa) were recognized by specific IgE. The 12–13 kDa and 22–33 kDa proteins could correspond to the main allergens. Conclusion White sesame seeds contain at least 10 allergenic proteins with acidic isoelectric points. In accordance with previous results, two of them seem to contain the major allergens. [ABSTRACT FROM AUTHOR]

Addition of hydrogen peroxide (H2O2) to blueberry juice changed the red coloration toward brown. Addition of ascorbic acid prevented the formation of brown polymers. An extract of peroxidase (POD) prepared from blueberry fruits was able to oxidize CG into the corresponding o-quinone but only in the presence of H2O2. The chlorogenoquinone plays a dominant role in anthocyanin degradation. We demonstrated that peroxidase extract in the absence of CG showed a weak degradation activity toward blueberry anthocyanins, cyanidin 3-glucoside, and pelargonidin 3-glucoside. Nevertheless, addition of CG increased anthocyanin degradation, leading to formation of brown polymers. Therefore, blueberry POD could participate in the development of browning during blueberry-juice storage. [ABSTRACT FROM AUTHOR]

Presents a paper which discusses how allergy to soy is an underestimated cause of food anaphylaxis. How soy has been responsible for several fatal and severe reactions; Conclusion that allergenic proteins were present in both cold-pressed and deodorized soy oil.

Biomass of Aspergillus niger was obtained from a microbial culture and a copper (Cu) induction was performed after 72 h of fermentation. The crude induced metallothionein extract was obtained by cell disruption and partly purified by a heat treatment and ultrafiltration. The purification of metallothionein by affinity chromatography resulted in three major fractions: FIVa, FIVb and FIVc3. Cu analysis demonstrated that only fraction FIVc contained the Cu-metallothionein. Spectrophotometric analyses of FIVc demonstrated the presence of a peak at 259 nm and a ratio of 78 mol of Cu per mol of protein. Electrophoretic analyses of FIVc, performed under denaturing conditions, showed the presence of one band with molecular mass of 21 kDa; however, two isoforms were observed under native conditions with molecular masses of 9.5 and 10.5 kDa and isoelectric points of 6.2 and 6.5, suggesting a recombination process due to denaturation.