New Sources of Calcium (Chicken Eggshells, Chelates) - Preparation of Raw Material and Tablets.

BACKGROUND: There are many calcium supplements available in the market, especially those containing calcium in the form of carbonate, which unfortunately is not absorbed by the body to a sufficient degree. METHOD: Therefore, an attempt was made to prepare new sources of calcium, consuming the chicken eggshells as natural raw materials, which were used in preparation of tablets containing calcium carbonate and calcium citrate as well as tablets with calcium carbonate and calcium bisglycinate. The influence of raw material properties on the pharmaceutical availability of calcium from the obtained tablets was investigated. RESULTS: Based on the obtained calcium release profiles from the prepared tablets, it was found that the optimal source of calcium is a preparation containing calcium from chicken eggshells. It was found that both chicken eggshells and calcium bisglycinate (chelate) may be new, prospective sources of calcium. Calcium citrate prepared using eggshells as starting materials and bisglycinate is completely released within no more than 150 minutes. CONCLUSION: In turn, calcium carbonate added to calcium bisglycinate statistically significantly prolonges the release of calcium ions to 4 hours.

Prenatal effects of natural calcium supplement on Wistar rats during organogenesis period of pregnancy.

The potential of oral exposure to calcium and magnesium citrate, a natural product obtained from dolomite, to initiate teratogenesis was analyzed in Wistar rats. Animals received calcium and magnesium citrate oral doses of 250, 500 and 1000 mg/kg during the period of gestation from day 6 to 17 post conception. Maternal, embryo and fetal toxicity was evaluated. Calcium and magnesium citrate exposure did not produce maternal toxicity assessed by clinical observations, body weight gain, food intake, hematology, biochemical parameters and necropsy finding. Signs of embryo-fetal toxicity were not observed. Skeletal and visceral malformations were seen occasionally in all drug-treated and control groups. Skeletal and visceral variations were similar in control and drug-treated groups except for incomplete ossification rib. These finding was spontaneous and unrelated to the drug. In conclusion, in this study we found that the oral exposure to rats of up to 1000 mg/kg of calcium and magnesium citrate during organogenesis did not induce significant maternal and embryo-fetal toxicity. The experimentally derived NOAEL for developmental toxicity was 1000 mg/kg.

[Studies on constituents of Rosa bracteata fruits(II)].

OBJECTIVE: To find the active constituents of Rosa bracteata Wendl. to antagonize withdrawal syndrome in morphinedependent mice. METHODS: The constituents were isolated and purified by silica gel chromatography repeatedly. Their structures were made clear by chemical reactions and on the evidence of spectroscopy. RESULTS AND CONCLUSIONS: Five compounds were isolated from the fruits and four of them were determined as trimethly citrate, dimethyl 3-carboxyl-3-hydroxypentanedioate, 3-hydroxy-3-methoxycarbonyl-pentanedioic acid, calcium citrate, which were found from the Rose genus plant for the first time.