Inhibitory Effect of Sodium Citrate, Sodium Nitrite and Cinnamaldehyde on Biofilm-forming Escherichia coli O157:H7

The development of biofilms by the foodborne pathogens attached to surfaces in the food processing environments results in the deterioration of products, persistence of pathogenic bacteria and transmission of food-associated diseases. In addition, biofilms are more resistant to antimicrobials than their planktonic counterparts which make their elimination from food and the food processing facilities a great challenge. This study aim was to determine the inhibitory effect of food additives on biofilm forming Escherichia coli O157:H7. The isolate obtained was subjected to Gram’s staining and various biochemical identifications and later confirmed by latex agglutination test. Biofilm formation potential was done on Congo red media and the confirmed biofilm former was subjected to biofilm formation at 10℃ and 37℃ for 168hrs. Antimicrobial susceptibility testing, MIC, MBC, and antibiofilm effect was determined following CLSI 2017 guideline. The highest zone of growth inhibition of 31 mm was exhibited by cinnamaldehyde, sodium nitrite with 26 mm and sodium citrate with 13 mm. The MIC 2.5 mg/mL was recorded for sodium citrate, 0.25 mg/mL for sodium nitrite and 0.125 μl/mL for cinnamaldehyde. Strong biofilm was formed at 37 ℃ with 7.82 x 109 CFU/mL viable cells at 168hrs while 6.79 x 109 CFU/mL were obtained at 10 ℃. All the three additives showed antibiofilm effect (at 10℃ and 37℃), cinnamaldehyde exhibited 70%-90.1%, sodium nitrite; 70%-88.2% inhibition and sodium nitrite; 75%-88% inhibition respectively. This study showed that sodium citrate, sodium nitrite and cinnamaldehyde exerted strong antimicrobial and antibiofilm properties indicating their potential as good preservatives.

Sorghum Protein Extract Protects RBC from Sodium Nitrite-Induced Oxidative Stress and Exhibits Anticoagulant and Antiplatelet Activity

Introduction: Oxidative stress plays a critical role in the progression of diabetes, arthritis, cancer, eryptosis, cardiovascular disease, and thrombosis. Currently, antioxidants from natural sources are in high demand due to their beneficial role in the management of said diseases. Aim: The purpose of the study was to evaluate the protective effect of sorghum protein buffer extract (SBE) on sodium nitrite-induced oxidative stress and thrombosis. Materials and methods: Protein characterization of SBE was done using SDS-PAGE. Oxidative stress in RBC was induced using sodium nitrite (NaNO2) and the key stress markers such as lipid peroxidation (LPO), protein carbonyl content (PCC), and the level of antioxidant enzymes (SOD and CAT) were measured. The anticoagulant effect of SBE was identified by employing in-vitro plasma recalcification time, activated partial thromboplastin time (APTT), prothrombin time (PT), and in-vivo mouse tail bleeding time. SBE antiplatelet activity was examined using agonist adenosine diphosphate (ADP) and epinephrine-induced platelet aggregation. Non-toxic property of SBE was identified using in-vitro direct haemolytic, haemorrhagic, and edema forming activities using experimental mice. Results: SBE revealed similar protein banding pattern under both reduced and non-reduced conditions on SDS-PAGE. Interestingly, SBE normalized the level of LPO, PCC, SOD, and CAT in stress-induced RBCs. Furthermore, SBE showed anticoagulant effect in platelet rich plasma by enhancing the clotting time from the control 250 s to 610 s and bleeding time from the control 200 s to more than 500 s (p<0.01) in a dose dependent manner. In addition, SBE prolonged the clot formation process of only APTT but not PT. SBE inhibited the agonists ADP and epinephrine induced platelet aggregation. SBE did not hydrolyze RBC cells, devoid of edema and haemorrhage properties. Conclusions: This study demonstrates for the first time the anticoagulant, antiplatelet, and antioxidant properties of SBE. Thus, the observed results validate consumption of sorghum as good for health and well-being.

Morphofunctional state of the medulla and the fascicular zone of the adrenal cortex in modeling Alzheimer's disease by excessive administration of sodium nitrite

Background. Nitrates and nitrites are found in soil, water, human food, dyes, and medicines. In the literature, both positive and negative effects from the ingestion of nitrates and nitrites into the body are considered. A nitrite model of Alzheimer's type dementia of vascular origin was used in the work. Objective. The aim of the study was to study the morphofunctional state of the adrenal glands of experimental animals with prolonged administration of sodium nitrite. The study was carried out on male rats of the WAG population, which were divided into 3 groups: gr. N-14 - received injections of a water solution of sodium nitrite at a dose of 50 mg / kg of body weight daily for 14 days; gr. N-28 - Rats received similar injections for 28 days. Injections are intraperitoneal. Control rats were injected with 0.9% sodium chloride solution. Results. In animals of the main groups, the formation of a morphofunctional picture of the development of a stress reaction takes place, which was also confirmed morphometrically, and in group N-28 - with signs of incipient decompensation of the medulla and the fascicular zone of the adrenal cortex. Conclusion. When simulating Alzheimer's disease in laboratory rats by the introduction of a water solution of sodium nitrite at a dose of 50 mg / kg of body weight by daily intraperitoneal injection for 14 and 28 days, a picture of their morphofunctional activation is formed in the medulla and fascicular zone of the adrenal cortex. In the group with a 28-day course of administration of sodium nitrite solution, morphofunctional signs of decompensation of the medulla and the fascicular zone of the adrenal glands (especially the medulla) appear, which indicates the development of severe distress in animals and the impossibility of restoring homeostasis.

Thermal Storage of Nitrate Salts as Phase Change Materials (PCMs)

This study presents the energy storage potential of nitrate salts for specific applications in energy systems that use renewable resources. For this, the thermal, chemical, and morphological characterization of 11 samples of nitrate salts as phase change materials (PCM) was conducted. Specifically, sodium nitrate (NaNO3), sodium nitrite (NaNO2), and potassium nitrate (KNO3) were considered as base materials; and various binary and ternary mixtures were evaluated. For the evaluation of the materials, differential Fourier transform infrared spectroscopy (FTIR), scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) to identify the temperature and enthalpy of phase change, thermal stability, microstructure, and the identification of functional groups were applied. Among the relevant results, sodium nitrite presented the highest phase change enthalpy of 220.7 J/g, and the mixture of 50% NaNO3 and 50% NaNO2 presented an enthalpy of 185.6 J/g with a phase change start and end temperature of 228.4 and 238.6 °C, respectively. This result indicates that sodium nitrite mixtures allow the thermal storage capacity of PCMs to increase. In conclusion, these materials are suitable for medium and high-temperature thermal energy storage systems due to their thermal and chemical stability, and high thermal storage capacity.