ABSORPTION OF CALCIUM IN SMALL INTESTINE OF RATS AFTER IMPACT OF VARIOUS XENOBIOTICS

Relevance. Pathology of the thyroid and parathyroid glands, diseases of the digestive system, blood system, etc, as well as application of medications used for their treatment can result in the condition which is characterised by reduction of bone density – secondary osteoporosis. The aim of the research was to determine absorption of calcium in the small intestine of rats under impact of various xenobiotics. Materials and methods. The research was performed on white rats of herd breeding which, depending on the group obtained during 60 days: 1) cefoperazone (p/o, 180 mg/kg per day) and amoxiclav (p/o, 135 mg/kg per day); 2) mercazolil (p/o, 25 – 40 mg/kg per day); 3) L-thyroxine (p/o, 10 mg/kg per day); 4) hydrazine sulphate (50 mg/kg 2 times per week for 90 days). Calcium absorption was studied in an isolated loop of the small intestine of the animals. The condition of the small intestine mucous membrane was estimated in accordance with inflammation markers (elastate and acid phosphatase activity, index of the degree of opportunistic microbiota (urease activity), index of non-specific antimicrobial protection of mucous membranes (lysozyme activity). Long-term application of antibiotics contributed to reduction of calcium absorption in the small intestine of rats by 25.0 %, of mercazolil – by 29.7 %, of thyroxine – by 11.4 %, of hydrazine sulphate – by 34.5 %. The increase of elastase and acid phosphatase activity in the mucous membrane of the small intestine under the action of xenobiotics, as well as increase of urease activity and reduction of lysozyme activity testify to the change in the small intestine condition. Сonclusions. So, the significant reduction of calcium absorption after long-term application of xenobiotics can be first of all connected with inhibition of antimicrobial protection of the small intestine mucous membrane under the action of antibiotics, mercazolil, thyroxine and hydrazine sulphate. More active multiplication of opportunistic bacteria, presence of dysbiosis, and, after application of antibiotics and hydrazine sulphate, development of inflammation can be the consequence of lysozyme activity reduction.

Removal of Lead from Water Using Calcium Alginate Beads Doped with Hydrazine Sulphate-Activated Red Mud as Adsorbent

Calcium alginate beads doped with hydrazine sulphate-treated red mud are investigated as adsorbent for extracting lead ions from water using batch methods of extraction. Different extraction conditions are optimised for maximum lead extraction. Substantial amount of lead is removed, and the adsorption ability is found to be 138.6 mg/g. Surface characterization using FTIR, EDX, and FESEM confirms that lead is “onto” the surface of the adsorbent. Thermodynamic parameters, adsorption isotherms, and kinetics of adsorption are analysed. Adsorption is “physisorption” in nature and spontaneous. The adsorbent developed can be regenerated using 0.1 M HCl. Thus regenerated adsorbent can be used as the adsorbent for further removal of lead at least 10 times, and this enables the complete removal of lead from water by repetitive use of the regenerated adsorbent. The beads facilitate the easy filtration. The methodology developed is successfully applied for removing lead from industrial waste waters.

Modifications of spectrophotometric methods for total phosphorus determination in meat samples

Spectrophotometric determination of total phosphorus in meat samples was modified using the molybdenum blue reaction with the following reducing agents: ascorbic acid (AA), hydrazine sulphate (HS), and mixture of hydroquinone and hydrazine sulphate (HHS). Proposed methods were validated by evaluation of statistical parameters such as: linearity, sensitivity, limits of detection (DL) and quantification (QL), precision, and accuracy, against the standard and malachite green (MG) modified procedures and by applying food certified materials. The values of within-day and between-days precision in meat samples for all tested reducing agents were better than 3.4 % and 4.2 %, respectively. The recoveries for CRMs analyses were between 92 % and 102.3 %. Obtained results suggest usefulness of the hydroquinone and hydrazine sulphate mixture in the determination of phosphorus ions.