Optical Properties of Crystalline Lactose Fluidized with Dilutions of Various Substances in the Terahertz Frequency Range

Lactose is a commonly used component of pharmaceutical medications in tablet form. It was previously shown that lactose changes conformationally after saturation in fluidized beds with active pharmaceutical ingredients obtained by repeated dilution of antibodies to interferon-gamma in combination with an external intensive vibration treatment. Moreover, it was revealed that these solutions are self-organized dispersed systems in which nano-objects are formed. Their biological activity and mechanism of action were previously established as well. The current work was dedicated to investigating the optical properties of fluidized lactose powders in the terahertz frequency range. Spectral analyses of powders of crystalline lactose saturated in fluidized beds with a diluted solution of either glycine buffer, antibodies to interferon-gamma, or water were carried out, intact lactose served as a control. All powders were tableted before testing. In the course of the study, the macroscopic parameters of the tablets were established, at which they had a stable shape and their THz optical properties had no parasitic diffraction losses. These tablets were analyzed using terahertz time-domain spectroscopy in the frequency range of 0.2–2.6 THz. The differentiation between the spectra was conducted using a principal component analysis. The differences between intact lactose and the lactose saturated with any of studied solutions were demonstrated. Additionally, lactose saturated with solutions of multiple dilutions of a substance (antibodies or glycine buffer) differed not only from intact lactose, but also from lactose saturated with a diluted solution of water. Moreover, discrimination of lactose formulations saturated with different substances (antibodies or glycine buffer) was also possible. Additionally, intact lactose differed from lactose saturated with diluted water. The methods reported could be useful for the quality control of the medications based on the technology of repeated dilution of an original substance.

Selection of the Optimal Medium for Adsorption of Plant Proteases

Immobilized enzymes are the most sought-after preparations in the global market. They are used in medicine, veterinary medicine, the food industry, winemaking and brewing. The simplest method for immobilizing biocatalysts on insoluble carriers is the simple adsorption method. Its advantage is that it preserves the natural conformation of the enzyme, which slightly reduces its catalytic ability compared to the native form. In our study, we carried out the selection of optimal conditions for adsorption immobilization of acid-soluble chitosan (Mr = 350 kDa) enzymes of plant origin (ficin, papain and bromelain) on a matrix. Ficin (EC 3.4.22.3), papain (EC 3.4.22.2) and bromelain (EC 3.4.22.4) (Sigma) were chosen as the objects of study, azocasein (Sigma) was used as a substrate for hydrolysis and an acid-soluble high-molecular-weight chitosan (350 kDa) was used as an immobilization matrix, synthesized by Bioprogress CJSC. Suitable buffer systems for immobilization were identified by the optimal ratio of protein content and total and specific activity. Ficin is immobilized on a chitosan matrix using glycine buffer with a pH of 8.6. Glycine buffer with a pH of 8.6–10.5 is an optimal medium for sorption of papain on chitosan. Bromelain is immobilized on a chitosan matrix under Tris-glycine buffer with pH 8.5 conditions.

Effect of Buffer and pH on the Protein Extraction for Chicken Meat

The study was undertaken to determine the extraction of proteins from chicken meat. The effect of buffer (phosphate, citrate and glycine) and four pH values (6.0, 7.0, 8.0 and 9.0) were investigated. The protein extractability of phosphate, citrate and glycine buffer with in the pH range (pH 6.0 to 9.0) was assessed to determine the best protein extractant for chicken meat. The maximum protein extractabilities at pH 8.0 for phosphate and citrate buffer, and at pH 9.0 for glycine buffer were observed. ANOVA analysis showed that there was no significant difference in protein extractabilities for citrate from phosphate and glycine buffer. Whereas, a significant difference was observed for phosphate buffer from glycine. However, no significant effects of pH were observed.

Swabs as a Tool for Monitoring the Presence of Norovirus on Environmental Surfaces in the Food Industry

Human norovirus (HuNoV), which causes gastroenteritis, can be transmitted to food and food contact surfaces via virus-contaminated hands. To investigate this transmission in food processing environments, we developed a swabbing protocol for environmental samples, evaluated the stability of HuNoV in the swabs, and applied the method in the food industry. Swabs made of polyester, flocked nylon, cotton wool, and microfiber were moistened in either phosphate-buffered saline (PBS) or glycine buffer (pH 9.5) and used to swab four surfaces (latex, plastic, stainless steel, and cucumber) inoculated with HuNoV. HuNoV was eluted with either PBS or glycine buffer and detected with quantitative reverse transcription PCR. HuNoV recoveries were generally higher with an inoculation dose of 100 PCR units than 1,000 PCR units. The highest recoveries were obtained when surfaces were swabbed with microfiber cloth moistened in and eluted with glycine buffer after a HuNoV inoculation dose of 100 PCR units: 66% ± 18% on latex, 89% ± 2% on plastic, and 79% ± 10% on stainless steel. The highest recovery for cucumber, 45% ± 5%, was obtained when swabbing the surface with microfiber cloth and PBS. The stability of HuNoV was tested in microfiber cloths moistened in PBS or glycine buffer. HuNoV RNA was detected from swabs after 3 days at 4 and 22°C, although the RNA levels decreased more rapidly in swabs moistened with glycine buffer than in those moistened with PBS at 22°C. In the field study, 172 microfiber and 45 cotton wool swab samples were taken from environmental surfaces at three food processing companies. Five (5.6%) of 90 swabs collected in 2010 and 7 (8.5%) of 82 swabs collected in 2012 were positive for HuNoV genogroup II; all positive samples were collected with microfiber swabs. Three positive results were obtained from the production line and nine were obtained from the food workers' break room and restroom areas. Swabbing is a powerful tool for HuNoV RNA detection from environmental surfaces and enables investigation of virus transmission during food processing.

Characterisation of Potato (Solanum tuberosum L.) Varieties by Electrophoresis of Tuber Proteins

The modified PAGE method (TRIS – Glycine buffer pH 8.9) was used for the characterisation of selected 25 registered potato varieties. This method enabled to identify each variety from the examined variety set. The calculation of identity indexes (proportion of common bands) helped to evaluate the similarity of varieties from these aspects. The examination of electrophoretic profiles of soluble tuber proteins, which are highly polymorphic and stable, can be considered as valuable for variety characterization and identification.  

Preliminary Study of the Autoantigens on the Membrane of Erythropoietic Cells of the Patients with BMMNC- Coomb’s Test(+) Hemocytopenia

Abstract 4382 Objective To observe the relationship between EPO receptor(EPOR) and autoantibodies-IgG/IgM(auto-Ab) on the membrane of erythropoietic cells of the patients with IRP and then explore the probable autoantigens of auto-Ab in IRP. Methods 46 newly diagnosed IRP patients(15 with auto-Ab on erythropoietic cells and 31 without auto-Ab on erythropoietic cells) and 18 healthy controls were enrolled in this study. EPOR expression on their nuclear erythrocytes were tested with FCM to observe the relationship between EPOR and auto-Ab; EPOR mRNA were tested by RT-PCR; Stat5 and P-Stat5 proteins in nucleared erythrocytes were measured by Western blot; EPOR expression on the nucleared erythrocytes membrane were tested again after stripping autoantibodies with glycine buffer. Results (1)EPOR of auto-Ab(+) arm(1.59±0.87)% was significantly lower than that of auto-Ab (−) arm(4.58±4.09)%(P<0.01)and the latter was significantly higher than that of normal controls(2.27±1.76)%(P<0.05); GEPOR of IRP patients was inversely correlated with their auto-Ab (r=−0.543,P=0.000).(2) EPOR mRNA of auto-Ab(+) arm(0.685±0.136)was significiantly higher than that of auto-Ab (−) arm(0.554±0.116)(P<0.01)and normal controls(0.580±0.119)(P<0.05);(3) Protein Stat5 of auto-Ab(+) arm(1.45±0.94) was significantly higher than that of normal controls(0.54±0.36)(P<0.05). While P-Stat5 of auto-Ab(+) arm(0.42±0.18) was significantly lower than that of normal controls(0.85±0.38)(P<0.05). (4) EPOR expression increased significantly after auto-Ab stripped from nucleared erythrocytes with glycine buffer. Conclusion The auto-Ab of some IRP patients might block or competitively inhibit the EPOR on the membrane of erythropoietic cells. EPOR might be one of autoantigens in IRP. Disclosures: No relevant conflicts of interest to declare.