Survey of tea for the presence of gluten.

In 2013, the U.S. Food and Drug Administration conducted a survey of green and white teas marketed in the northeastern United States for the presence of undeclared wheat. Based on the requirement for concurrence between the RIDASCREEN gliadin (R5) enzyme-linked immunosorbent assay (ELISA) and the Morinaga Institutes of Biological Science (MIoBS) wheat protein ELISA, none of the 20 products included in the survey tested positive for wheat, rye, barley, or gluten. However, eight of the teas generated responses indicative of the presence of gluten with the RIDASCREEN gliadin (R5), AgraQuant gluten G12, and Aller-Tek (Skerritt) sandwich ELISAs. Five of the eight teas generated responses indicative of >20 ppm of gluten using the RIDASCREEN and AgraQuant ELISA test kits, and all eight had ≥ 20 ppm based on the Aller-Tek ELISA. Extracts prepared using the RIDASCREEN validated protocol and the MIoBS validated sodium dodecyl sulfate plus ß-mercaptoethanol (overnight) protocol were analyzed using both test kits. The extracts prepared using the RIDASCREEN protocol tested positive for gluten with both test kits. Western blot analyses of the two sets of extracts using the R5 and MIoBS antibodies to visualize the bands revealed the presence of antigenic proteins in both sets of extracts, although the profiles and band intensities were different and inconsistent with the ELISA results. These results raise questions regarding the screening procedures used to detect gluten and how the observation of a homologous antigenic element is defined.

A two-generational reproductive toxicity study of zinc in rats.

A two-generation reproductive toxicity study of zinc chloride (ZnCl(2)) was conducted in rats. F(o) male and female rats were administered 0.00 (control), 7.50 (low), 15.00 (mid) and 30.00 (high) mg/kg/day of ZnCl(2). Selected F(1) male and female rats were exposed to the same doses received by their parents (F(o)). Exposure of F(0) parental rats to ZnCl(2) showed significant reduction in fertility, viability (days 0 and 4), and the body weight of F(1) pups from the high-dose group but caused no effects on litter size, weaning index, and sex ratio. Similarly, the continued exposure of F(1) parental rats to ZnCl(2) also reduced fertility, liter size, viability (day 0), and the body weight of F(2) pups within the high-dose group but caused no effects on weaning index and sex ratio. Exposure of ZnCl(2) to F(0) and F(1) parental males resulted in a significant reduction in their body weights, and the F(0) and F(1) parental females did not show any significant difference in their body weights compared to their control groups. However, the postpartum dam weights of both F(0) and F(1) female rats were significantly reduced compared to their controls. Exposure of ZnCl(2) to F(o) and F(1) generation parental rats did not produce any significant change of their clinical signs as well as their clinical pathology parameters, except the alkaline phosphotase (ALK) level, which showed an upward trend in both sexes of both generations. Exposure of ZnCl(2) to F(0) rats resulted in a reduction of brain, liver, kidney, spleen and seminal vesicles weights of males and in the spleen and uterus of females. Similarly, exposure of F(1) rats to ZnCl(2) also resulted in reduction of brain, liver, kidney, adrenal, spleen, prostate and seminal vesicles weights of males and in spleen and uterus of females. ZnCl(2) exposure resulted in grossly observed gastro-intestianla (GI) tract, lymphoreticular/hematopoietic, and reproductive tract lesions in parental rats in both generations. Reduced body fat was also recorded in F(1) parental rats.

Bioavailability of calcium from sweetpotato and soy flour supplemented diets in hamsters.

The bioavailability of calcium from two varieties of sweetpotatoes and supplementation of sweetpotatoes with soy flour was investigated in hamsters using plasma calcium concentration and femur calcium content as indicators. Five different diets were fed to five groups of animals for 28 days. There was no significant difference in plasma calcium concentrations of hamsters in all the diet groups. However, the femur calcium content of hamsters with transgenic sweetpotato flour (TSPF) and parent nontransgenic (from which transgenic was produced) sweetpotato flour (NTSPF) diets was significantly higher than that of the transgenic sweetotato flour supplemented with soy flour (TSPF + SF) and parent nontransgenic sweetpotato flour supplemented with soy flour (NTSPF + SF) diets. The relative bioavailability of calcium from the control (100%), TSPF+SF (30%), NTSPF+SF (23%), TSPF (57%) and NTSPF (46%) indicated that sweetpotatoes could be the better source of calcium, however, supplementation with soy flour might reduce the bioavailability of calcium.