High Concentrations Of Histamine Research Articles

Histochemical and immunohistochemical investigation of the number and localization of mast cells in the feline tongue.

This is the first study to describe the subtypes, number and distribution of mast cells (MC) in cat tongue by histochemical and immunohistochemical methods. Six male adult felines' tongue tissue samples consist of the study's material. Samples were fixed in 10% formaldehyde. MC number and distribution in the feline tongue were assessed using toluidine blue. Also, sections taken from blocks were stained in alcian blue/safranin O (AB/SO) combined dyes to determine the MC subtypes. The Streptavidin biotin complex method using anti-chymase and anti-tryptase primary antibodies was used for immunohistochemistry. Metachromatic MCs were mainly observed in the lamina propria close to the multilayered keratinized stratified squamous epithelium. The high number of MCs in this region may be because the dorsal surface of the tongue plays an essential role in the defence system of tongue tissue and, thus, of the body as a whole. Additionally, the number of MCs stained with AB (+) (1.7 ± 0.08) in the feline tongue was statistically higher than those with SO (+) (0.18 ± 0.02). This might be interpreted as an indication that MC heterogeneity may be due not only to their staining properties but also to their localization. It is also conceivable that the high histamine content may be a factor in this. Tryptase-positive MCs were found in the loose connective tissue around blood vessels, between the glands, as solitary cells, or in groups of several cells. Chymase-positive MCs were observed more individually rather than in groups. Moreover, chymase-positive MCs were detected to be located in the filiform papillae subepithelial and in the blood vessels' immediate vicinity. Animals often lick themselves to clean themselves and promote healing. For this reason, it is very important to protect the tongue, which is in direct contact with the external environment, against foreign agents. Considering both the functional and protective properties of the tongue, we concluded that MCs may play a role in oral cavity immunity and protective effect.

Simultaneous detection of gizzerosine and its precursor histamine in feeds and raw materials using UHPLC–MS/MS to evaluate feed safety risks

Gizzerosine is a biogenic amine in feeds with a physiological toxicity 1,000 times that of its precursor, histamine, causing high mortality in poultry. Because feeds containing gizzerosine usually contain high concentrations of histamine, it is of great significance to establish a method for the simultaneous detection of gizzerosine and histamine for feed safety. Herein, we first developed a detection method using 50 % (v/v) acetonitrile(ACN) containing 1 % (v/v) ammonium hydroxide (AH) extraction to synchronously monitor gizzerosine and histamine in feeds and raw materials via UHPLC–MS/MS. Due to the serious positive matrix effect (ME) in existing LC–MS/MS, this study reduced the ME of samples by purifying the extract solution using a mixed-mode cation exchange based solid phase extraction column (MCX-SPE), and simultaneously obtained accurate quantities of 5–500 ng mL−1 gizzerosine and 25–2,500 ng mL−1 histamine. The limit of detection (LOD) values for gizzerosine and histamine were 1.02 ng mL−1 and 3.00 ng mL−1, respectively, which were approximately 390 and 8,000 times more sensitive than the maximum recommended dosage of gizzerosine (0.4 mg kg−1) and limitation standards of histamine (25 mg kg−1) in fish meal, respectively. The samples could only be evaluated in 2 h. The average recoveries of the 6 types of feeds and raw materials ranged from 79.73 % to 110.31 % with a relative standard deviation (RSD) ranging from 1.29 % to 13.35 %. The average recoveries of feeds were generally lower than those of raw materials. Our method was efficient, simple, rapid, accurate, sensitive, and suitable for the simultaneous quantitative analysis of gizzerosine and histamine contents in various feeds, which provided technical support for the quality evaluation of feeds.

Removal of Histamine from Fish Sauce by Staphylococcus debuckii sp. Isolated from Fermented Fish.

One of the issues in the production of fish sauce is the legal constraints on the concentration of histamine produced by bacteria during fermentation because it causes allergic reactions in humans. The goal of this study is therefore to eliminate histamine from the final product after fermentation to enhance the quality of fish sauce for consumer safety, manufacturer exportability and domestic sales. The bacteria that grow in the histamine medium were isolated from the salted fish. Their ability to degrade histamine in the media with high NaCl content was tested. The bacterium with the highest histamine-degrading ability was identified and the histamine-degrading conditions were optimized, including the incubation temperature and the amount of NaCl in the medium. The regression equation was generated and tested using the local fish sauce in which different concentrations of histamine were added. Among the five bacteria isolated from the salted fish, the isolate with the greatest ability to degrade histamine was identified as Staphylococcus debuckii sp. The study of the capacity of the isolated bacteria to degrade histamine using the synthetic histamine broth (pH=7.0, t=25 °C and NaCl 25 % (m/V)) indicated that they were able to degrade up to 56 % of histamine. The optimization analysis showed that increasing the pH of the medium to 7.5 and lowering the incubation temperature to 20 °C could improve the histamine removal from 56 to 73 %. The generated regression model, validated by the experimental results of histamine removal from fish sauce, showed an acceptable error (not more than 10 %). S. debuckii, the isolated histamine-degrading bacteria, could be used as an inoculum to reduce histamine accumulated in fish products. The microbiological technique developed here can decrease the histamine concentration in the final product, fish sauce, to improve its quality in terms of food safety and satisfy the histamine regulation requirement. The findings of this study can also be used to treat other liquid foods that contain high concentrations of histamine.

Intrinsic Factors Contributing to Shrimp and Blood Clamp Allergic Reaction and Allergic Like Symptoms

Factors that contribute to food allergenicity is still unknown. To determine food intrinsic properties that contribute to L. vannamei and A. granosa allergenicity or allergy like symptoms this study identify total protein and metal profiles, histamine contents, and protein heat stability. Histamine content is measured colorimetrically. Protein heat-stability is observed with sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS-PAGE). Allergy-related metal concentration are determined with Atomic Absorption Spectroscopy (AAS). Fresh L. vannamei and A. granosa contained ~100 and ~25 ppm histamine, respectively. Storage at -20 oC for 3 days relatively did not changed histamine content of both foods. Storage at 4-8 oC for 3 days increased histamine content in L. vannamei, but not in A. granosa. Protein sized <70 kDa of both samples are relatively heat-stable. L. vannamei and A. granosa contained Zn with concentration of 85 ppm and 92 ppm, subsequently. All samples did not contain nickel (Ni), chromium (Cr), and lead (Pb). Higher histamine content and heat-stable protein number of L. vannamei could contribute to higher prevalence of its allergy or allergic like symptoms than A. granosa. High Zn content might contribute to allergic like symptoms of both foods.

The significance of cheese sampling in the determination of histamine concentration: Distribution pattern of histamine in ripened cheeses

Cheeses are becoming a major safety and public health concern: cheeses available in supermarkets occasionally contain high histamine concentrations that can have negative effects on consumer health. In this study, we have attempted to assess the histamine distribution pattern in ripened cheeses, with the purpose of establishing a correct cheese sampling strategy for the quantification of histamine. To this aim, histamine was determined in four distinct areas of twelve long-ripened hard cheeses: the external and internal rind, along with the outer and inner core of the wedge. The concentrations measured were remarkably different: histamine accumulated in the central core, whereas the lowest amount was found in the peripheral rind. To explain this heterogenous distribution, histamine producers were determined in the four areas by identifying the hdc sequences obtained from cheese samples. Non-starter bacteria were identified as main histamine producers; however, these microbiota were homogeneously distributed throughout the wedge. Nevertheless, the analysis of psychochemical properties of the different areas revealed an observable trend: histamine tended to accumulate in the saltier, more humid, and less oxidized areas in a wedge. Overall, this study highlights the significance of a correct sampling strategy when histamine is quantified in cheese.

Histamine promotes adhesion of neutrophils by inhibition of autophagy in dairy cows with subacute ruminal acidosis.

Subacute ruminal acidosis (SARA), a common digestive disease in dairy cows, is accompanied by systemic inflammation and high concentrations of histamine in blood. Histamine-induced neutrophil adhesion may play an important role in the systemic inflammation experienced by cows during SARA. Autophagy, an intracellular degradation system, regulates recycling of membrane-associated integrin and may be involved in histamine-induced adhesion of bovine neutrophils. In the present study, 20 multiparous mid-lactation cows (average body weight 486 ± 24 kg) fitted with ruminal fistula were assigned to a control group (n = 10) or a SARA group (n = 10). We induced SARA by feeding different combinations of wheat-barley pellets and chopped alfalfa hay for 8 wk; SARA was defined as a ruminal pH <5.6 for at least 3 h/d. Blood samples were collected in wk 8. Compared with controls, SARA cows had greater serum concentrations of tumor necrosis factor-α, IL-6, IL-1β, lipopolysaccharide (LPS)-binding protein, haptoglobin, and serum amyloid A. Serum concentrations of these proinflammatory factors had strong positive correlations with the concentration of serum histamine and LPS. In ex vivo adhesion experiments, the number of adherent neutrophils was greater in the SARA group. Additionally, membrane protein abundance of adhesion molecules such as integrin α-L precursor (CD11a) and integrin α-M precursor (CD11b) was greater in neutrophils of the SARA group, confirming enhanced adhesion ability. Neutrophils of SARA cows had greater number of autophagosomes, greater protein abundance of autophagy substrate sequestosome-1 (p62), and higher ratio of microtubule associated proteins 1A/1B light chain 3 (LC3)-II to LC3-I, indicating congestion during the late phase of autophagy flux. For in vitro experiments, neutrophils isolated from control cows were incubated with 0.4 endotoxin units (EU)/mL LPS or 7 μM histamine for 0, 1, 2, and 4 h, respectively. We detected linear and quadratic effects for the number of adherent neutrophils after histamine treatment with a peak response at 2 h, whereas no significant effect was detected after LPS treatment. Membrane protein abundance of CD11a and CD11b was greater after histamine treatment, suggesting that it may have an inhibitory effect on the degradation of adhesion molecules. The greater abundance of p62, higher ratio of LC3-II to LC3-I, and increased co-localization between CD11b and LC3 after histamine treatment indicated that recycling of adhesion molecules and autophagy flux were blocked. These effects were not aggravated further in the presence of chloroquine, a specific inhibitor of the late phase of autophagy flux. Overall, our results revealed that histamine increases adhesion of neutrophils by inhibiting autophagy in dairy cows with SARA.

ANTIBACTERIAL POTENCY OF CELL FREE SUPERNATANT PRODUCED BY LACTIC ACID BACTERIA ISOLATED FROM INDONESIAN FERMENTED FISH PRODUCTS AGAINST HISTAMINE-PRODUCING BACTERIA

The toxicity caused by high histamine content produced by histamine-producing bacteria (HPB) during the fermentation of scombridae fish group based fermented fish products is still a problem that requires a solution. This study aims to explore the potential of secondary metabolites in the form of cell free supernatant (CFS) produced by lactic acid bacteria (LAB) as antibacterial agents against HPB. The LAB was isolated from the fermented fishery products named bekasan, cincalok and fish sauce using MRS-Agar and fermented on MRS-broth for 48 hours. CFS was collected by centrifugation at 15,000 x g for 15 minutes, followed by heating at 100oC for 3 minutes and pH neutralization with 0.1N NaOH. Antimicrobial activity of CFS then tested on HFB namely Morganella morganii TK7, Citrobacter freundii CK1, and Klebsiella sp. CK13.2 (collection of the Laboratory of Fisheries Product Quality and Safety, Department of Fisheries UGM) using the macrodilution method. Isolation of LAB from all three products successfully isolated 34 isolates. The results of the antibacterial activity showed that 4 isolates namely GMCN 1.12, GMBK 2.6, GMBK 2.7, dan GMKI 2.1 were able to inhibit HFB growth more than 70%. The highest activity was shown by GMBK 2.7 which inhibits 98% against Morganella morganii TK7, 99% against Citrobacter freundii CK1, and 84% against Klebsiella sp. CK13.2. The antimicrobial activity was reduced after proteolytic enzymes were added suggesting that the bioactive compound came from peptide-based substances like bacteriocin.

Rapid and Wash-Free Time-Gated FRET Histamine Assays Using Antibodies and Aptamers.

Histamine (HA) is an indicator of food freshness and quality. However, high concentrations of HA can cause food poisoning. Simple, rapid, sensitive, and specific quantification can enable efficient screening of HA in food and beverages. However, conventional assays are complicated and time-consuming, as they require multiple incubation, washing, and separation steps. Here, we demonstrate that time-gated Förster resonance energy transfer (TG-FRET) between terbium (Tb) complexes and organic dyes can be implemented in both immunosensors and aptasensors for simple HA quantification using a rapid, single-step, mix-and-measure assay format. Both biosensors could quantify HA at concentrations relevant in food poisoning with limits of detection of 0.19 μg/mL and 0.03 μg/mL, respectively. Excellent specificity was documented against the structurally similar food components tryptamine and l-histidine. Direct applicability of the TG-FRET assays was demonstrated by quantifying HA in spiked fish and wine samples with both excellent concentration recovery and agreement with conventional multistep enzyme-linked immunosorbent assays (ELISAs). Our results show that the simplicity and rapidity of TG-FRET assays do not compromise sensitivity, specificity, and reliability, and both immunosensors and aptasensors have a strong potential for their implementation in advanced food safety screening.

Identification by means of molecular tools of the microbiota responsible for the formation of histamine accumulated in commercial cheeses in Spain

Histamine intoxication is an important food safety and public health concern. Ripened cheeses are the most common dairy products in which histamine can accumulate. Histamine is formed by the microbiota present in cheese by decarboxylation of histidine, due to the action of the histidine decarboxylase. This study's objective was to identify the responsible for the formation of histamine accumulated in commercial cheeses. The content of histamine of 39 different types of cheeses marketed in Spain, of varying milk origin, was assessed. About one third of the cheeses analysed contained more than 200 mg/kg histamine; two cheeses exceeded 500 mg/kg histamine, the consumption of such cheeses can be harmful or even toxic for consumers. The five cheeses with the highest histamine concentrations were selected for in-depth molecular analysis. Firstly, bacterial and yeast isolates were obtained, and then the total genetic material from the cheeses was analysed, in order to verify the putative presence of the hdc histidine decarboxylase gene. In order to identify the histamine producing microorganisms, the nucleotide sequences of the histidine decarboxylase genes from the cheeses were amplified, and subjected them to Sanger sequencing. In four of the five selected cheeses, the main histamine producer was identified as Lentilactobacillus parabuchneri, whereas in the remaining cheese it was Tetragenococcus halophilus. The hdc gene was located in an unstable plasmid, only present in that cheese sample. Since all histamine producing microorganisms identified in this study are not part of the species used in cheese starter cultures, an improvement of hygienic manufacturing practices and/or thermal treatments for microbial inactivation in milk may be considered to prevent histamine accumulation in cheeses during ripening.

Are there profiles of cheeses with a high GABA and safe histamine content?

Some bacteria decarboxylate amino acids as a means of resisting acid stress. It is a mechanism commonly used by bacteria in fermented dairy products. The decarboxylation of histidine to histamine occurs frequently in some types of cheese, but high concentrations of histamine can be harmful to consumers. Not all amino acid decarboxylation products are, however, undesirable. GABA, the decarboxylation product of glutamate, has positive effects on human health. Although histamine and GABA accumulate in large quantities in many types of cheese, there is little information regarding their relationship, and that which is available is restricted to a few cheese varieties. The present work examines whether cheeses exist with high concentrations of GABA but safe concentrations of histamine. The GABA and histamine contents of 250 cheeses representing 143 European varieties were examined, and the technological, environmental and metabolic (TEM) traits governing their accumulation identified. Two TEM profiles were associated with high GABA contents and safe histamine concentrations. These findings could help the dairy industry select the best technological conditions for making GABA-rich, histamine-safe cheeses. • GABA and histamine were determined in 250 cheeses of 143 different varieties. • GABA (healthy) and histamine (toxic) can accumulate at high concentrations. • A positive correlation exists between GABA and histamine concentration. • Cheeses with high GABA and low histamine contents were identified. • The technological/environmental/metabolic profiles of these cheeses were recorded.

Genetic and Phenotypic Diversity of Morganella morganii Isolated From Cheese.

The bacterium Morganella morganii can produce the biogenic amines (BA) cadaverine, putrescine, and histamine in vitro and is responsible for high histamine concentrations in fish products. These BA can have toxic effects upon ingestion and are undesired in food. The purpose of this study was to characterize the phenotype and genotype of 11 M. morganii isolated from cheese in regard to the BA formation. In addition, we investigated the phylogeny, trehalose fermentation ability, and antibiotic resistance of the cheese isolates. To do so, we sequenced their genomes using both long and short read technologies. Due to the presence of the trehalose operon and the ability to ferment trehalose, the cheese isolates can be assigned to the subsp. sibonii. Comparative genomics with public available M. morganii genomes shows that the genomes of the cheese isolates cluster together with other subsp. sibonii genomes. All genomes between subsp. morganii and subsp. sibonii are separated by an average nucleotide identity (ANI) of less than 95.0%. Therefore, the subspecies could represent two distinct species. Nine of the strains decarboxylated lysine yielding cadaverine in vitro. This metabolic activity is linked to a previously unknown gene cluster comprising genes encoding a lysine-tRNA ligase (lysS), an HTH-transcriptional regulator (argP), a cadaverine-lysine antiporter (cadB), and a lysine decarboxylase (cadA). The formation of putrescine is linked to the speF gene encoding an ornithine decarboxylase. The gene is disrupted in five strains by an insertion sequence, and these strains only exhibit a weak putrescine production. Antimicrobial susceptibility profiling revealed that all cheese strains are resistant to tetracycline, chloramphenicol, tigecycline, colistin, and ampicillin. These phenotypes, except for colistin which is intrinsic, could be linked to antimicrobial resistance genes located on the chromosome.

Variances in the Expression of mRNAs and miRNAs Related to the Histaminergic System in Endometrioid Endometrial Cancer.

Research has indicated higher concentrations of histamine and polyamine in endometrioid tissue in comparison with healthy tissue. The aim of this study was to evaluate changes in the expression patterns of messenger RNA (mRNAs) and microRNA (miRNAs) related to the histaminergic system in endometrial samples and whole blood in women with endometrioid endometrial cancer. The study group consisted of 30 women with endometrioid endometrial cancer qualified for hysterectomy (G1 well-differentiated, 15 cases; G2 moderately differentiated, 8 cases; and G3 poorly differentiated, 7 cases). The control group included 30 women with no neoplastic changes during routine gynecological examinations. The molecular analysis consisted of the microarray analysis of mRNAs and miRNAs related to the histaminergic system, reverse-transcription quantitative polymerase chain reaction (RTqPCR), and enzyme-linked immunosorbent assay (ELISA). Out of 65 mRNAs connected with the histaminergic system, 10 differentiate the samples of tissue and blood obtained from patients with endometrioid endometrial cancer in comparison with the control group (p < 0.05). mRNA histamine receptor 1,3 (HRH1, HRH3), and solute carrier family 22 member 3 (SLC23A2) differentiating samples of endometrioid endometrial cancer independent of either G or control. The highest probability of interaction, based on the target score miRDB, between the selected miRNAs and mRNAs was found for the hybrids hsa-miR-1-3p and endothelin 1 (END1), hsa-miR-27a-5β and SLC23A2. The selected mRNA and miRNA transcripts seem to be promising for molecularly targeted therapies in the context of endometrioid endometrial cancer.

Влияние спиртового и яблочно-молочного брожения на содержание биогенных аминов в винах

Introduction. The concentration of biogenic amines is an important indicator of the safety of food products, especially winemaking. In grape wines, this concentration varies widely depending on the grape variety, its microbiological state, processing technology, the race of yeast and bacteria of malolactic fermentation, conditions of alcoholic and malolactic fermentation, etc. This research is aimed at determining the effect of the production technology of dry white and red wines on the concentration of biogenic amines.&#x0D; Study objects and methods. The mass concentration of biogenic amines was determined by the method of high-performance capillary electrophoresis using a Kapel 105R in laboratory-obtained samples of dry white wine from the Chardonnay grape variety and table dry red wine from the Cabernet-Sauvignon grape variety.&#x0D; Results and discussion. The dry white wine samples revealed high concentrations of tyramine (1.12 mg/dm³), phenylethydamine (0.58 mg/dm³), and histamine (0.57 mg/dm³), while the red wine samples demonstrated tyramine (0.62 mg/dm³), histamine (0.45 mg/dm³), putrescine (0.43 mg/dm³), and cadaverine (0.38 mg/dm³). The white wine samples had optimal pH values (3.2–3.6) with minimal formation of biogenic amines. The red wine samples, especially those obtained by heat treatment, had a lower concentration of biogenic amines, especially volatile biogenic amines, i.e. methylamine and phenylethylamine. The greatest formation of biogenic amines occurred during the acid reduction process: under the effect of enzymes of malolactic bacteria, biogenic amines formed as a result of decarboxylation of amino acids. &#x0D; Conclusion. The technology of production of table dry white and red wines affects the concentration of biogenic amines. To reduce the level of biogenic amines in the finished product, each stage of vinification has to be controlled, especially the stages of fermentation and acid reduction (temperature and pH). The race of yeast and lactic acid bacteria cannot include those that produce biogenic amines or introduce them in minimal quantities.

Influence of Sample Matrix on Determination of Histamine in Fish by Surface Enhanced Raman Spectroscopy Coupled with Chemometric Modelling

Histamine fish poisoning is a foodborne illness caused by the consumption of fish products with high histamine content. Although intoxication mechanisms and control strategies are well known, it remains by far the most common cause of seafood-related health problems. Since conventional methods for histamine testing are difficult to implement in high-throughput quality control laboratories, simple and rapid methods for histamine testing are needed to ensure the safety of seafood products in global trade. In this work, the previously developed SERS method for the determination of histamine was tested to determine the influence of matrix effect on the performance of the method and to investigate the ability of different chemometric tools to overcome matrix effect issues. Experiments were performed on bluefin tuna (Thunnus thynnus) and bonito (Sarda sarda) samples exposed to varying levels of microbial activity. Spectral analysis confirmed the significant effect of sample matrix, related to different fish species, as well as the extent of microbial activity on the predictive ability of PLSR models with R2 of best model ranging from 0.722–0.945. Models obtained by ANN processing of factors derived by PCA from the raw spectra of the samples showed excellent prediction of histamine, regardless of fish species and extent of microbial activity (R2 of validation > 0.99).

An Instant, Safe, Antihistamine, Anti-Inflammatory and Decongestant Polymeric Nasal Barrier to Prevent and To Treat Allergic Rhinitis in Children

Introduction: Allergic rhinitis (AR) in children is a common chronic pathology with a strong impact on patient quality of life. The main physiopathology affects the nasal cavity as a multi-factorial disease involving nasal mucosa damage, nasal inflammation with high concentrations of histamine, pro-inflammatory cytokines such as histamine, TNF-α, IL-4, IL-5, IL-6, IL-10, IL-13, and IgE antibodies on the nasal mucosa. Systemic entry of these proteins through damaged nasal mucosa maintains continued inflammatory and allergen cascades. Therefore, an ideal treatment should be multitarget in order to stop allergen exposure, inflammation, and nasal mucosa barrier degradation, but such treatments are nearly impossible to conceive. We envisaged an osmotic and protective nasal barrier film, not only capable of protecting the nasal mucosa from allergen exposure but also of trapping and neutralizing selected cytokines and cleaning the nasal surface continuously without using any harmful substance for children. Materials and Methods: We associated highly osmotic glycerol solution with specific plant polymers to conceive an osmotic but stable film. As plant polymers (tannins) can bind with selective proteins, a range of glycerol binding non-cytotoxic polymers were screened using the sandwich ELISA method to select those having binding affinity for allergen induced nasal proinflammatory cytokines. After verifying cytotoxicity and irritant potential, a 15-day observational clinical study was performed with approval from the ethics committee on 30 children aged between 4-13, suffering from allergic rhinitis. The test product (TP) was supplied in 15-ml nasal sprays and applied 2-3 times per day for a period of 15 days. Saline solution served as control (CP). The scores of nasal and ocular symptoms, effect on quality of life, eosinophil count in nasal smears, and need for antihistamine treatment was evaluated at the start, at 30 minutes and on days 2, 3 and 15 of treatment. Results: A few specific polymers were able to bind with selected cytokines and histamine at adequate filmogen concentrations. The osmotic film was stable, non-irritant and was able to clean the nasal mucosa continuously for 4-6h after each application. Clinical observations of Total Nasal Symptom Score (TNSS) grouping the scores of nasal congestion, runny nose, sneezing, and itching, revealed a strong decrease right after the 1st treatment in both groups but the reduction was much stronger and faster with the TP. The mean TNSS score reduction was 44.74% in CP vs 83.53% in the TP group after 7 days of treatment (p&lt;0.001). Total Ocular Symptom Score (TOSS) was decreased by 21.13% and 51.41% in CP v/s 35.12 and 99.59% in TP group on days 2 and 7, respectively. Nasal smear eosinophil count was equally strongly reduced in the TP v/s CP group. No treatment-related side effects were recorded in any of the groups. Conclusion: Protecting the nasal mucosa against allergens, neutralizing inflammatory cytokines, and keeping the nasal surface clean with an osmotic polymeric film, constitute a major breakthrough for the treatment of allergic rhinitis in children. This simple but scientific and logical approach should avoid exposing children to chemicals and to their long-term side effects.

Contamination of smoked fish and smoked-dried fish with polycyclic aromatic hydrocarbons and biogenic amines and risk assessment for the Beninese consumers

The present study aims to assess the contamination of smoked and smoked-dried fish sampled on Beninese market with biogenic amines and polycyclic aromatic hydrocarbons (PAHs). Fifteen PAHs, ten biogenic amines and nineteen amino acids were analysed in thirty-six fish samples, using liquid chromatography techniques. The assessment of consumer exposure was carried out by calculating the estimated daily intake (EDI) which was compared to a toxicological reference value. The exposure to histamine, the most toxic biogenic amine, was calculated and compared with an acute reference dose (ARfD) of 50 mg/meal. The margin of exposure (MOE) to PAHs was calculated as the ratio between benchmark PAH levels and EDI. MOE to carcinogenic compounds below 10,000 indicates a potential concern for human health. Amino-acid profile varied as a function of fish species with a high content of histidine (the precursor of histamine) recorded in Cypselurus cyanopterus, the Atlantic flying fish (2.9 g/100 g, dry weight) followed by Scomber scombrus, the Atlantic mackerel (1.9 g/100 g, dry weight). High histamine concentration (4,384.2 mg/kg) was recorded in one sample of C. cyanopterus, a non-scombroid fish, exceeding 44 times the maximal limit of 100 mg/kg, set by the EU and Benin regulations. Histamine intake calculated using the maximum measured histamine concentration exceeded the ARfD. Concerning the PAH contamination, none of the smoked and smoked-dried fish samples were compliant with the EU regulation, and the MOE of the consumers were below 10,000 (for both median and maximum PAH contamination levels). In conclusion, the consumption of smoked and smoked-dried fish could represent a major concern for the Beninese consumer health because of both histamine and PAHs contamination.

Determination of Biogenic Amines in Different Parts of Lycium barbarum L. by HPLC with Precolumn Dansylation.

The aim of this work was to characterize biogenic amines (BAs) in different parts of Lycium barbarum L. using HPLC with dansyl chloride derivatization, and jointly, to provide referential data for further exploration and utilization of Lycium barbarum L. The linear correlation coefficients for all BAs were above 0.9989. The limits of detection and quantification were 0.015–0.075 and 0.05–0.25 μg/mL, respectively. The relative standard deviations for the intra-day and inter-day precision were 0.66–2.69% and 0.91–4.38%. The described method has good repeatability and intermediate precision for the quantitative determination of BAs in different parts of Lycium barbarum L. Satisfactory recovery for all amines was obtained (79.3–110.3%). The result showed that there were four kinds of BAs. The highest putrescine content (20.9 ± 3.2 mg/kg) was found in the flower. The highest histamine content (102.7 ± 5.8 mg/kg) was detected in the bark, and the highest spermidine (13.3 ± 1.6 mg/kg) and spermine (23.7 ± 2.0 mg/kg) contents were detected in the young leaves. The high histamine (HIS) content in the bark may be one of the reasons why all of the parts of Lycium barbarum L., except the bark, are used for medicine or food in China. Meanwhile, the issue of the high concentration of HIS should be considered when exploiting or utilizing the bark of Lycium barbarum L.

Assembly of hyperhalophilic complex consortia of isolates from anchovy ripening attaining histamine degradation and their microbiome configuration

High histamine content in salted-ripened fish results in food safety detriment. The present study focused on the assembly of mixed cultures from halophilic prokaryotes isolated during salting-ripening anchovy process in order to determine their histamine-degrading capacity. For this purpose, 57 halophilic prokaryotes were inoculated together and submitted to several enrichment steps with strong shifts in culturing conditions and three microbial consortia were subsequently assembled: original consortium named C1 (without histamine exposure), consortium C2 (enriched in nutritive culture medium with high histamine content ~900 mg/kg) and consortium C3 (against histamine ~200 mg/kg) and reduced amounts of nutrients. These consortia were submitted to histamine-degrading capacity studies and 16S rRNA gene amplicons analysis. In the absence of histamine (C1), Salinivibro costicola (16.83%), Haloarcula spp. (11.08%) and Halococcus spp. (8.73%) were the most abundant. C2 presented ability to degrade histamine and major OTUs belonged to the family Halobacteriaceae and the genus Halomonas. C3 degraded histamine and predominant OTUs were from the family Halomonadaceae and the genus Chomohalobacter. Therefore, members of the archaeal family Halobacteriaceae and bacterial genera Halomonas and Chomohalobacter would be associated to histamine degradation and their potential as single or mixed starter cultures for improving salted-ripened foodstuff safety is promising.

Histamine accumulation in dairy products: Microbial causes, techniques for the detection of histamine-producing microbiota, and potential solutions.

Histamine poisoning is a significant public health and safety concern. Intoxication from ingestion of food containing high amounts of histamine may cause mild or severe symptoms that can even culminate in cardiac arrest. Nonetheless, although histamine levels in dairy products are not subject to any regulation, important outbreaks and severe adverse health effects have been reported due to intake of dairy products with a high histamine content, especially ripened cheeses. Histamine, a biogenic amine, can accumulate in dairy products as a result of the metabolism of starter and nonstarter lactic acid bacteria, as well as yeasts that contribute to the ripening or flavoring of the final product, or even as a result of spoilage bacteria. The aim of this review is to describe the microbiological causes of the presence of histamine in fermented milk products, and to propose control measures and potential methods for obtaining histamine-free dairy products. Thus, this manuscript focuses on histamine-producing microbiota in dairy products, highlighting the detection of histamine-producing bacteria through traditional and novel techniques. In addition, this review aims to explore control measures to prevent the access of histamine-producing microbiota to raw materials, as well as the formation of histamine in dairy products, such as a careful selection of starter cultures lacking the ability to produce histamine, or even the implementation of effective food processing technologies to reduce histamine-producing microbiota. Finally, the removal of histamine already formed in dairy products through histamine-degrading microorganisms or by enzymatic degradation will also be explored.

Clinical efficacy and safety of omalizumab in conventional treatment-resistant vernal keratoconjunctivitis: Our experience and literature review.

Clinical efficacy and safety of omalizumab in conventional treatment-resistant vernal keratoconjunctivitis: Our experience and literature review.