Mono-and Binuclear Cobalt(II) Mixed Ligand Complexes of 2,2’-Bipyridine and Ethylenediamine: Synthesis, Characterization and Biological Application

Antibiotic resistance of pathogens to the current commercially available drugs is a serious problem. To curve this problem, the discovery of active compounds with a new mode of action is insistent. In line with this, we report two new complexes; mononuclear [Co(L1)2(L2)(H2O)]Cl2 and binuclear [Co2(L1)4(L2)(H2O)2]Cl4 using precursor complex, [Co(L1)2(H2O)2]Cl2, synthesized before; where L1: 2,2’-bipyridine and L2: ethylenediamine. The precursor complex was prepared from CoCl2.6H2O and L1 in ethanol, treated with a different mole of L2 under optimized reaction conditions to give the corresponding mono-and binuclear cobalt(II) mixed ligand complexes. These complexes were characterized using the spectroscopic technique (ICP-OES, UV-Vis, FT-IR) and physicochemical methods (chloride determination, thermal analysis, and conductance measurement). Their antibacterial activities were also tested against two Gram-negative (Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae)) and two Gram-positive (Staphylococcus aureus (S. aureus), Streptococcus pyogenes (S. pyogenes)) bacteria using the disc diffusion method. The new complexes showed better activities against K. pneumoniae than the reference Gentamycin. Furthermore, [Co(L1)2(L2)(H2O)]Cl2 demonstrated better activity than Gentamycin against S. aureus and E. coli.

Changes in protein substances of brynza cheese under the influence of partial replacement of salt with potassium chloride

The results of studies of protein substances of brine cheese from sheep milk with partial replacement of salt with potassium chloride in the amount of 20 and 30 % are presented in the article. Benefits of cheese as a foodstuff are a large number of vitamins B, A, E, it is rich in minerals, including trace elements and essential amino acids. The bacterial preparation RSF-742 in combination with Fresh-Q (Chr. Hansen, Denmark) was used to make the cheese, which adversely affects the development of yeast and mold, thus extending the shelf life of the cheese. Two groups of cheese were made. The first group (without Fresh-Q): K (control) using NaCl; D1 and D2 with 20 % and 30 % replacement of NaCl by KCl, respectively. Second group (with Fresh-Q): CF using NaCl; DF1 and DF2 with 20 and 30 % replacement of NaCl by KCl, respectively. The Kjeldahl method was used to determine the content of total Nitrogen, total soluble Nitrogen, Nitrogen of non-protein soluble nitrogen-containing compounds. The positive effect of salt replacement and the use of biosecurity culture on the course of proteolytic processes has been proved. Nitrogen content of soluble protein substances, which determines the dietary properties of cheese, increased in samples with 20 and 30 % replacement of table salt with potassium chloride. Determination of digestibility of proteins by digestive enzymes in vitro was performed using the basic method Pokrovsky-Ertanov. The essence of the method consists in the sequential effect on the protein of the object under study of the proteinase system and the removal by dialysis of some hydrolysis products to avoid inhibition of the reaction by low molecular weight peptides and free amino acids. Brynza with partial replacement of sodium chloride with potassium chloride is characterized by better digestibility compared to cheese, which is made by traditional technology. The data are confirmed by high rates of digestibility. The test specimens of the breeze according to these indicators fully meet the requirements of the current regulatory documentation.

The development of technology of rickot cheese from whey, obtained using various coagulants

The problem of obtaining and rational use of whey proteins in human nutrition today is solved all over the world, traditional methods are being improved and new, more effective ways of processing milk whey, aimed at maximizing the withdrawal and use of its proteins, are being developed. The aim of the research was to develop the technology of albumin cheese ricotta from serum derived by the action of various coagulants. The raw material for cheese production was serum. For the study, two samples of cheese (with a threefold repetition) were made: Sample 1 - using serum formed during the fermentation of proteins with the participation of citric acid (normalized mixture + enzyme + citric acid); Sample 2 – using serum formed during protein mixing with the direct introduction of the fermentation culture (normalized mixture + enzyme + culture + calcium chloride). Determination of organoleptic and physico-chemical parameters in samples of albumin cheese, obtained from the developed technology, was carried out immediately after manufacture. The study of organoleptic characteristics of cheeses showed a similarity of indicators in samples 1 and 2. In particular, it was stated that pure, fresh taste and smell, with a specific albumin flavor, without foreign flavors and odors. Consistency in 1 sample was homogeneous, creamy, in 2 samples it was tender, but with a slight splinting. The color of the cheeses was white uniform throughout the mass. The lower acidity in the sample 2, which was at 17 °T, whereas in the sample 2 was higher – 20 °T. This, in particular, is explained by the use of citric acid for coagulation. The changes of microbiological parameters in the raw materials during storage, which consisted in the growth of the number of mesophilic anaerobic and optional aerobic microorganisms in two samples of cheese, were established. Given the permissible level of the number of mesophilic anaerobic and optional aerobic microorganisms in cheese not more than 1 × 105 CFU/g, the shelf life of two samples of cheese for 5 days. Indicators of titrated acidity during storage were correlated with changes in the number of mesophilic anaerobic and optional aerobic microorganisms. The mass fraction of moisture in the samples of cheese in the process of their storage decreased.

Salt content in bread in Spain, 2014

Introduction: Excess salt intake is associated to the risk of high blood pressure and cardiovascular disease. Bread is one of the foods that contributes the most salt to the diet in Spain. It is important to monitor the salt content of bread.Objective: To quantify the amount of salt in bread in Spain in 2014, and to compare it to the amount of salt in 2008.Methods: This Cross-sectional study was conducted in Spain in 2014. 1,137 loaves of bread (barra, a Spanish style of bread, similar in shape to a baguette, baguettes and wholemeal) were purchased at bakeries with and without on-site workrooms and at supermarkets in all of Spain’s Autonomous Communities. Salt content (g/100 g bread) was analysed by determining total sodium. In one subsample, 2014 mean salt content was compared to previous data of 2008 salt content (chloride determination).Results: The mean salt content was 2.08 g (SD: 0.32) with a minimum value of 0.30 and a maximum of 3.33. The mean salt content was similar in barra- and baguette-type breads (2.09 g) and somewhat lower in wholemeal. The mean salt was 2.07 g/100 g in breads made with fresh dough and 2.12 g/100 g in breads made with frozen dough. The mean salt content (chlorides) was 1.64 g (SD: 0.42) in 2014 and 1.63 g (SD: 0.37) in 2008. This was not a significant difference (p=0.428).Conclusions: The amount of salt in common bread in Spain remains stable from 2008.

A Kinetic Photometric Method For Benzalkonium Chloride Determination In Eye Drops

A novel sensitive kinetic photometric method for the Benzalkonium Chloride (BAC) determination has been developed. The method is based on the ability to inhibit the reaction of Acetylcholine hydrolysis by cholinesterase. The reaction rate is evaluated by the non-hydrolysed Acetylcholine residue, which is determined by the amount of Peracetic acid, produced during the interaction with the excess of H 2 O 2 . Indicator reaction is an interaction of p-phenetidine with Peracetic acid that leads to the formation of 4,4'-azoxyphenetole with λ max = 358 nm (lg ε = 4.2). The conditions affecting the reaction (reagents concentration, pH, order of addition of reagents, stability in time) have been optimized. The linear dependence has been obeyed in the range of (1.4-8.4)·10 -6 mol L -1 of BAC with correlation coefficient of 0.999. The assay LOQ (20 % of the inhibition degree) has been 1.9·10 -6 mol L -1 . The proposed method has been successfully applied to the analysis of the eye drops and has shown an accuracy and reliability of the results obtained.