Search Results (170)

Consumer demand for organic and nitrite-free meat products has stimulated the search for sustainable alternatives to synthetic curing agents. Conventional nitrites are effective in stabilizing color, inhibiting lipid oxidation, and suppressing pathogens, but their use raises health concerns due to potential nitrosamine formation. This study investigated the application of Portulaca oleracea powder as a multifunctional ingredient to fully replace sodium nitrite in organic cooked frankfurters. Two formulations were produced: control frankfurters with sodium nitrite and experimental frankfurters with purslane powder 1.2%. Physicochemical, oxidative, proteomic, and antioxidant parameters were monitored during refrigerated storage. Purslane incorporation improved the lipid profile by increasing α-linolenic acid and lowering the ω-6/ω-3 ratio, while peroxide, thiobarbituric acid reactive substances (TBARS), and acid values remained significantly lower than in nitrite-containing controls after 10 days. Protein oxidation was also reduced, and SDS-PAGE profiles confirmed that the major structural muscle proteins remained stable, indicating that purslane addition did not disrupt the core proteome. Antioxidant assays showed strong ferric-reducing antioxidant power (FRAP) activity 13.7 mg GAE/g and enhanced 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging capacity 22.3%, highlighting purslane’s contribution to oxidative stability. Although redness (a*) was lower than in nitrite controls, overall color stability (L*, b*) remained high. Taken together, purslane enhanced oxidative stability and quality attributes of nitrite-free organic frankfurters; microbiological validation is ongoing and will be reported separately. Full article

Nitrosamines, including N-nitroso diethylamine (NDEA) have emerged as pharmaceutical impurities and carcinogenic environmental contaminants of grave public health safety concerns. This study reports on the preparation and first use of cysteine–gold nanoparticles (CysAuNPs) for colorimetric detection of NDEA in human serum albumin (HSA) under physiological conditions. Molecular docking (MD) and molecular dynamic simulation (MDS) were performed to probe the interaction between NDEA and serum albumin. UV–visible absorption and fluorescence spectroscopy, dynamic light scattering (DLS), and transmission electron microscopy (TEM) imaging were used to characterize the synthesized CysAuNPs. These CysAuNPs show a UV–visible absorbance wavelength maxima (λ_max) at 377 nm and emission λ_max at 623 nm. Results from DLS measurement revealed the CysAuNPs’ uniform size distribution and high polydispersity index of 0.8. Microscopic imaging using TEM showed that CysAuNPs have spherical to nanoplate-like morphology. The addition of NDEA to HSA in the presence of CysAuNPs resulted in a remarkable increase in the absorbance of human serum albumin. The interaction of NDEA–CysAuNPs–HSA is plausibly facilitated by hydrogen bonding, sulfur linkages, or by Cys–NDEA-induced electrostatic and van der Waal interactions. These are due to the disruption of the disulfide bond linkage in Cys–Cys upon the addition of NDEA, causing the unfolding of the serum albumin and the dispersion of CysAuNPs. The combined use of molecular dynamic simulation and colorimetric experiment provided complementary data that allows robust analysis of NDEA in serum samples. In addition, the low cost of the UV–visible spectrophotometer and the easy preparation and optical sensitivity of CysAuNPs sensors are desirable, allowing the low detection limit of the CysAuNPs sensors, which are capable of detecting as little as 0.35 µM NDEA in serum albumin samples, making the protocol an attractive sensor for rapid detection of nitrosamines in biological samples. Full article

The search for natural alternatives to sodium nitrite in meat products is driven by concerns about consumer health and the need to maintain product quality and safety. In this study, the effect of sodium nitrite reduction on the quality parameters of canned pork meat with 1% lyophilized cell-free supernatant (CFS) from L. paracasei B1, during 30 days of storage, was assessed. Reduction of sodium nitrite content led to measurable changes in the color, texture, and oxidative stability of canned pork; however, the presence of 1% CFS helped preserve color, alleviated the negative impact on textural parameters, and limited lipid oxidation, thereby counteracting the typical consequences of nitrite reduction. Among the tested variants, S_75, containing 75% of the standard nitrite dose, showed the best overall balance between color retention, textural integrity, and oxidative stability. Samples without nitrite (S_0) exhibited a noticeable increase in lightness (L*) and decrease in redness (a*) over time, accompanied by a shift towards yellow-brown hues (b*, C*, H°). Importantly, the total color difference (ΔE) was least pronounced in the S_75 variant, with values of approximately 2.5 after 1 day and 2.7 after 30 days, which was markedly lower than in S_50 (ΔE ≈ 6.0 and 3.9) and S_0 (ΔE ≈ 7.9 and 8.5), thereby confirming superior color retention and overall stability during storage. Texture analysis showed that initial hardness and chewiness were higher in nitrite-free samples (S_0), suggesting that the complete omission of nitrite may negatively affect product structure. Nevertheless, all variants softened during storage, and samples with higher nitrite content, particularly S_75, retained better elasticity and cohesiveness. Lipid oxidation, expressed as TBARS values, progressed fastest in samples completely depleted of nitrite (S_0), increasing from 0.31 mg MDA/kg (day 1) to 1.35 mg MDA/kg (day 30), which confirms the antioxidant role of sodium nitrite. Interestingly, the presence of 1% CFS in the variants with reduced nitrite content partially mitigated this effect, as TBARS values in S_75 increased only from 0.29 to 0.46 mg MDA/kg, and, in S_50, from 0.45 to 0.66 mg MDA/kg, compared to the nitrite-free variant. This suggests that CFS may also have contributed to antioxidant protection. Fatty acid profiles remained relatively consistent across methods. Microbiological analysis revealed no significant differences between groups. These results demonstrate that partial nitrite reduction combined with CFS is effective, highlighting the potential of CFS as a promising functional additive in clean label meat preservation. Furthermore, reducing the sodium nitrite content in canned pork products may contribute to improved consumer health by reducing exposure to potentially harmful nitrosamine precursors. Full article

Nitrosamine impurities have provoked numerous global medicine recalls due to their possible presence during drug manufacturing or storage. Regarding formulation of nitrosamine impurities, a key risk involves reactions between nitrosating agents (nitrite) in excipients and vulnerable amines as impurities or degradants. Rapid detection across various sample types is essential to support pharmaceutical manufacturing. In this study, two methods were developed to detect nitrite in excipients and crucial secondary amines in active ingredient metformin hydrochloride at trace levels, respectively. The former method was developed based on the reaction of nitrite ions with 2,3-diaminonaphthalene to form 1-[H]-naphthotriazole (NAT), whereas the latter was based on amine tosylation. Mass spectrometric conditions were optimized using electrospray ionization in the positive mode. Multiple reaction monitoring transitions were determined at m/z 170 → 115 for NAT, and m/z 200.1 → 91 for dimethylamine (DMA) and 228.1 → 91 for diethylamine (DEA). These methods were validated using selected eight excipients or metformin hydrochloride in terms of specificity, linearity, accuracy, precision, robustness, limit of quantification (LOQ), and limit of determination according to the ICH guidelines. The results of the validation were within the acceptable criteria. Applicability of the methods was evaluated using 170 pharmaceutical samples donated by industries. The nitrite content in the excipients ranged from <LOQ to 4.74 ppm, with observed levels 1.3 to 6 times higher than the average (0.8 ppm) in the samples. The DMA levels in the metformin hydrochloride were within the limit (500 ppm) but varied significantly (0.2–209.2 ppm) among manufacturers. DEA was detected at lower levels (0.7–0.9 ppm). To mitigate the nitrosamine content in the metformin products, the excipient compositions were investigated by selecting those with low nitrite levels. As the types of impurities detected have become increasingly diverse and detection cycles have become more frequent, the requirement for preemptive safety management to relieve public anxiety is essential for regulatory aspects. Nitrite and secondary amines are crucial precursors to N-nitrosamine, and the suggesting approach could be a means to mitigate N-nitrosamine contamination. Full article

Sodium nitrite is an additive commonly used in meat processing to provide technological effects. However, the presence of nitrates in food can lead to the formation of carcinogenic N-nitrosamines; so, its use should be limited. This study concerns the possibility of reducing sodium nitrite (III) addition in the production of canned meat to 50 mg/kg by enriching the product with tomato peels and seeds powder (TPSP). The aim of this study was to evaluate the effect of TPSP on the physicochemical, chemical and microbiological quality of canned pork. Four different products were tested in this study: a control sample and samples with the addition of 0.5%, 1.5%, and 2.5% tomato peels and seeds powder. The addition of TPSP decreased the pH values of meat products and increased yellowness (b*) and redness (a*) values. The influence of TPSP on the increase in antioxidant activity of canned meat was also observed. However, the plant-based additive did not affect the chemical composition or water activity of the tested product. The control samples were characterized by a lower TBARS compared to the other samples of meat products. Microbiological analysis results indicate that the canned pork samples meet the product requirements. The most commonly isolated species from the samples were Enterobacter cloacae, Serratia liquefaciens, and Enterococcus faecalis. Full article

The term ‘vaping’ refers to the use of electronic cigarettes or other devices to inhale a variety of heated and aerosolized substances. Vaping has been promoted as a less harmful and potentially oncogenic alternative to nicotine cigarettes, particularly to help heavy smokers quit. While vaping products do not produce the same carcinogenic substances—such as polycyclic aromatic hydrocarbons—generated by the combustion of tobacco, and while their fluids lack tobacco-related carcinogens like nitrosamines, it is now well established that they still generate harmful and potentially oncogenic byproducts. Several mechanisms have been proposed to explain the potential oncogenic effects of vaping fluids, including direct chemical action, epithelial–mesenchymal transition induction, redox stress, mitochondrial toxicity, and DNA damage. In addition to cancer risk, there have been reports of adverse effects on cardiovascular health, reproductive function, and non-oncologic lung injuries. These include exogenous lipoid pneumonia, diffuse alveolar hemorrhage with proven alveolar injury, and vaping-associated bronchiolitis obliterans. The aim of this review is to examine vaping devices, their potential role in lung carcinogenesis, vaping-associated lung injury, and other clinical implications, including impacts on cardiovascular, cerebrovascular, and respiratory diseases, and also pregnancy and fetus health. Full article

Nitrosamines (NAs) are toxic compounds associated with disinfection processes. Human exposure can occur through the hydraulic hoses and seals that are in contact with drinking water. This study develops and validates a chromatographic method to quantify 11 NAs in water leachates from four organic materials. The method is based on liquid–liquid extraction (LLE) followed by gas chromatography coupled with mass spectrometry (GC-MS). The method was validated by the application of several statistical tests, namely, linearity/working range, precision, trueness, and recovery tests. The GC-MS method showed a good linear range for all NAs with coefficients of determination (r²) higher than 0.9989, coefficients of variation of the method (CVm) lower than 2.5%, and PG < F (0.05; 1; N-3). The working range varies between 10 µg/L and 386.7 µg/L. The GC-MS method showed good precision under repeatability and reproducibility conditions with a relative standard deviation (RSD) lower than 12% and 10%, respectively. The GC-MS showed good trueness with a relative error lower than 20%. Matrix effects were significant, with recovery (Rec) values between 47% and 125% and an RSD lower than 20%. The limit of detection (LOD) and quantification (LOQ) ranged between 0.71 µg/L and 8.9 µg/L and between 2.3 µg/L and 29.8 µg/L, respectively. The method quantification limits (MQL) ranged from 0.0045 µg/L to 0.0378 µg/L. The sum of the MQL (0.2 µg/L) is lower than the reference limit of 0.3 µg/L for NAs in the leachates from the migration tests. Four organic materials were subjected to migration tests with demineralized and chlorinated water to assess their suitability for the water supply system. These materials met the NA specifications for use in the water network. Full article

N-Nitrosodimethylamine (NDMA) is a widely recognized disinfection by-product that poses significant carcinogenic risks in drinking water. Conventional methods for NDMA removal, such as nanofiltration and reverse osmosis membranes, have limited efficacy due to NDMA’s small molecular weight and polar properties. Advanced oxidation processes (AOPs) have shown promise, but traditional Fenton processes often fall short due to the chemical structure of nitrosamines in NDMA. This study proposes a novel, cost-effective approach using a one-step carbonization method to synthesize a catalyst from ferric ammonium citrate (FAC). The resulting FAC-600 integrates zero-valent iron and iron carbide with carbon-based functional groups, enhancing catalytic and electron transport activities. Our experiments demonstrated that the FAC-600/persulfate (PS) AOP system achieves over 90% NDMA removal across a wide concentration range (50 μg L⁻¹ to 1000 μg L ⁻¹) with a limited dosage of 0.5 g L⁻¹. Mechanistic insights revealed that superoxide and hydroxyl radicals dominate NDMA degradation, facilitated by the presence of dissolved oxygen and PS. This study underscores the potential of the FAC-600/PS AOP system as a robust and efficient solution for NDMA removal, promising safer drinking water through practical application. Full article

This study presents a sustainable, environmentally friendly synthetic route for the production of key intermediates in losartan using palladium nanoparticles (PdNPs) derived from a brown seaweed, Sargassum incisifolium, as a recyclable nanocatalyst. A key intermediate, biaryl, was synthesized with an excellent yield (98%) via Suzuki–Miyaura coupling between 2-bromobenzonitrile and 4-methylphenylboronic acid, catalyzed using bio-derived PdNPs under mild conditions. Subsequent bromination using N-bromosuccinimide (NBS) under LED light, followed by imidazole coupling and tetrazole ring formation, allowed for the production of losartan with an overall yield of 27%. The PdNP catalyst exhibited high stability and recyclability, as well as strong catalytic activity, even at lower loadings, and nitrosamine formation was not detected. While the overall yield was lower than that of traditional industrial methods, this was due to the deliberate avoidance of the use of toxic reagents, hazardous solvents, and protection/deprotection steps commonly used in conventional routes. This trade-off marks a shift in pharmaceutical process development, where environmental and safety considerations are increasingly prioritized in line with green chemistry and regulatory frameworks. This study provides a foundation for green scaling up strategies, incorporating sustainability principles into drug synthesis. Full article

Nitrosamines (NAs) are a class of chemical compounds predominantly formed during the processing, curing, and storage of meat products through the reaction of nitrites with amines. Decades of toxicological and epidemiological evidence have unequivocally established several NAs as potent human carcinogens, with strong associations with gastrointestinal, pancreatic, and liver cancers. This review critically examines the pathways of NA formation in meat, the influence of processing conditions, and the factors contributing to their variability in food products. It also outlines state-of-the-art analytical techniques for their detection and summarizes recent scientific efforts to reduce their formation. Despite scientific consensus on the health hazards posed by dietary exposure to NAs, regulatory control remains fragmented and insufficient. Therefore, this review highlights the pressing need for coordinated international action and the development of a harmonized regulatory framework to mitigate public health risks. Full article

Many studies are being conducted on the detection of nitrosamine impurities in solid formulations. However, research on semi-solid formulations such as gels, ointments and creams is not common. In particular, excipients used to increase viscosity and add fragrance can significantly impact the sample preparation. Volatile compounds derived from natural fragrances are composed of a wide variety of complex components, making them very difficult to handle and completely separate from the analytes. Due to the complex composition of these formulations, an analytical method was developed to accurately separate and analyze nine nitrosamine impurities (NDMA, NDEA, NMEA, NDPA, NDBA, NPIP, NMOR, DIPNA and EIPNA) simultaneously. To overcome challenges in the sample preparation of excipients with physical and chemical properties, the sample was prepared using solvents such as methanol, hexane, water and dichloromethane. The target analytes were extracted with dichloromethane for the final preparation for GC–MS/MS and the optimal conditions were established. While multiple GC columns were tested, peak overlapping interferences were observed, leading to the use of a 60m-long column to overcome peak overlap. The GC–MS/MS condition was set for optimal performance and ionization energy, with parameters adjusted for each analyte. The developed method was validated in accordance with guidelines to ensure its reliability and suitability. As a result, all nine nitrosamine impurities were simultaneously analyzed, confirming excellent performance. The sample preparation method and procedure, column specification and GC–MS/MS conditions have the potential to be adapted not only for semi-solid formulations of pharmaceuticals and cosmetics but also for other formulations such as solid and liquid samples, rendering them suitable for the analysis of nitrosamine impurities. Full article

The illegal treatment of tuna with nitrite is a significant food safety concern. The risk may be due to not only the high nitrite levels and the possible formation of N-Nitrosamines but also to the possible increase in biogenic amines and microbial load and also pathogens. This study optimized the treatment of red tuna (Thunnus thynnus) with nitrite solutions and then determined several chemical (histamine, total volatile basic nitrogen (TVBN), biogenic amines, nitrite/nitrate, ascorbic acid, and sulfites) and microbiological (total microbial count, Enterobacteriaceae, Vibrionaceae, coagulase-positive staphylococci, Salmonella, Escherichia coli) parameters, comparing the results obtained with fresh samples with those obtained with treated samples after 5 days of storage (4 °C). The effect of such treatment on samples voluntarily contaminated with some pathogens was also investigated. The results indicate that if the products are characterized by suitable hygienic quality, the total microbial load and the levels of histamine and TVBN after 5 days of storage are below the legal limits, and no health risk subsists. The growth of pathogens/histaminogens (Salmonella and Morganella morganii) was also substantially inhibited during storage. Thus, this work confirmed that the high nitrite amounts and the possible development of N-nitrosamines represent the only significant food safety concerns. Full article

Vegetables, as an important source of vitamins and minerals, are highly recommended in a healthy diet. At the same time, vegetables can contain elevated amounts of nitrates and nitrites, which are the possible nitrosating agents responsible for the formation of carcinogenic nitrosamines. In young children, they can cause methemoglobinemia. Determining the level of nitrates and nitrites, as well as the possible reduction in their concentrations during culinary processing, is especially important for the diet of young children, who are introduced to leafy vegetables during the first year. For some types of vegetables that are often found in the diet, maximum permissible concentrations have not yet been established. Our goal was to estimate the reduction factors of nitrates and nitrites and suggest the best ways to properly prepare foods. For this purpose, samples of Swiss chard, spinach, and white cabbage were collected from the market to determine the nitrate and nitrite content. Vegetable samples were subjected to culinary preparations: soaking, cooking, and a combination of soaking and cooking. Quantitative and qualitative determination of nitrates and nitrites in vegetables was carried out on high-performance liquid chromatography (HPLC) equipped with a diode array detector (DAD). The obtained results showed that the highest nitrate concentrations were in Swiss chard samples, followed by spinach, and the lowest in white cabbage samples. The impact of culinary preparation was highest on spinach samples. Considering the average nitrate concentrations achieved after cooking or soaking and cooking, there was no risk of exceeding the ADI limit. However, the ADI values would be exceeded at the maximum nitrate concentrations. Full article

Introduction: Diethyl nitrosamine (DEN), a known carcinogen, has been used for validating the RasH2 and P53 transgenic models in chemical testing and has been shown to enhance primary liver tumor growth in the ATT-Myc transgenic mouse model of liver cancer. Material and Methods: to better understand the mechanism of hepatocellular carcinoma acceleration following DEN, BHT and vehicles treatments in ATT-Myc, transgenic and non-transgenic, mice. We employed an exon array, RT-PCR, Western blotting, and IHC to investigate the complex interplay between the c-Myc transgene and other growth factors in treated mice versus control transgenic and non-transgenic mice. Results: Notably, DEN treatment induced a 12-fold increase in c-Myc expression compared to non-transgenic mice. Furthermore, tumor growth in the DEN group was strongly associated with increased proliferation of transformed or carcinogenic hepatocytes, as evidenced by proliferative cell nuclear antigen and bromodeoxyuridine expression. Internally, the loss of c-Met signaling, enriched transcription factors, and the diminished expression of antioxidants, such as superoxide dismutase (SOD1) and NRF2, further enhanced c-Myc-induced liver tumor growth as early as four months post-DEN treatment. Discussion: Extensive tumor growth was observed at 8.5 months, coinciding with the downregulation of tumor suppressors such as p53. In contrast, at these time points, ATT-Myc transgenic mice exhibited only dysplastic hepatocytes without tumor formation. Additionally, the antioxidant butylated hydroxytoluene maintained c-Met expression and did not promote liver tumor formation. Conclusions: the persistent upregulation of c-Myc in the ATT-Myc liver cancer model, at both the gene and protein levels following DEN treatment inhibited the ETS1 transcription factor, further exacerbating the decline of c-Met signaling, SOD1, and NRF2. These changes led to increased reactive oxygen species production and promoted rapid liver tumor growth. Full article

Background/Objectives: Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta, leading to motor symptoms such as tremor, rigidity, and bradykinesia. The pathological hallmarks of PD include Lewy bodies and mechanisms like oxidative/nitrosative stress, chronic inflammation, and mitochondrial dysfunction. Nitric oxide (NO), produced by nitric oxide synthase (NOS) isoforms, plays a dual role in neuroprotection and neurodegeneration. Excessive NO production exacerbates neuroinflammation and oxidative/nitrosative damage, contributing to dopaminergic cell death. This review explores NO’s role in PD pathogenesis and investigates dietary nitrate as a therapeutic strategy to regulate NO levels. Methods: A literature review of studies addressing the role of NO in PD was conducted using major scientific databases, including PubMed, Scopus, and Web of Science, using keywords such as “nitric oxide”, “NOSs”, “Parkinson’s disease”, and “nitrate neuroprotection in PD”. Studies on nitrate metabolism via the nitrate–nitrite–NO pathway and its effects on PD hallmarks were analyzed. Studies regarding the role of nitrosamine formation in PD, which are mainly formed during the nitrification process of amines (nitrogen-containing compounds), often due to chemical reactions in the presence of nitrite or nitrate, were also examined. In particular, nitrate has been shown to induce oxidative stress, affect the mitochondrial function, and contribute to inflammatory phenomena in the brain, another factor closely related to the pathogenesis of PD. Results: Excessive NO production, particularly from iNOS and nNOS, was strongly associated with neuroinflammation and oxidative/nitrosative stress, amplifying neuronal damage in PD. Dietary nitrate was shown to enhance NO bioavailability through the nitrate–nitrite–NO pathway, mitigating inflammation and oxidative/nitrosative damage. Conclusions: Dysregulated NO production contributes significantly to PD progression via inflammatory and oxidative/nitrosative pathways. Dietary nitrate, by modulating NO levels, offers a promising therapeutic strategy to counteract these pathological mechanisms. Further clinical trials are warranted to establish its efficacy and optimize its use in PD management. Full article