Sensitive Reaction Research Articles

Tailoring reduced mechanisms for predicting flame propagation and ignition characteristics in ammonia and ammonia/hydrogen mixtures

Ammonia, as a carbon-free energy carrier, has been of emerging interest to reduce carbon footprint in the propulsion and power sectors. An accurate understanding and modeling of ammonia combustion are of fundamental and practical significance to its application implementation. In consideration of the complexity of ammonia-based chemical mechanisms, this work develops 4 reduced mechanisms based on a detailed one without modifying the rate coefficients. The applicability of these mechanisms is widely validated against experimental data in the literature. The overall agreement of model predictions with experimental values is satisfactory. For NH3/air flames, all mechanisms well describe the laminar burning velocity at elevated inlet temperatures, but the Mech20 presents a slight over-estimation, signifying the relative significance of reactions involving N2H3 and N2H4. Meanwhile, these reactions are extremely important in capturing propagation characteristics of NH3/H2/air mixtures. Both the original and reduced mechanisms over-predict the ignition delay time in NH3/air flames to some extent, which deserves further optimization. Sensitivity analyses identify the top 10 sensitive reactions regarding flame propagation and ignition characteristics, which vary significantly with kinetic mechanisms, especially in NH3/H2/air flames. Generally, the mechanisms developed applies to the ammonia combustion for most operating conditions considered and provide insights into the fundamental knowledge.

Assessment of Immediate Allergic Reactions After Immunization With the Pfizer BNT162b2 Vaccine Using Intradermal Skin Testing With the COVID-19 Vaccines

BackgroundAllergic reactions to the coronavirus disease 2019 (COVID-19) vaccines have raised concerns, particularly as repeated doses are required. Skin tests with the vaccines excipient were found to be of low value, whereas the utility of skin tests with the whole vaccine is yet to be determined.ObjectiveTo evaluate a panel of skin tests and the outcomes of subsequent doses of immunization among subjects who suffered an immediate allergic reaction to the BioNTech (BNT162b2) COVID-19 vaccine.MethodsBetween March and December 2021, patients who experienced symptoms consistent with immediate allergic reactions to the BNT162b2 vaccine and were referred to the Sheba Medical Center underwent skin testing with polyethylene glyol (PEG)-containing medicines, Pfizer-BNT162b2, and Oxford–AstraZeneca vaccine (AZD1222). Further immunization was performed accordingly and under medical observation.ResultsA total of 51 patients underwent skin testing for suspected allergy to the COVID vaccines, of which 38 of 51 (74.5%) were nonreactive, 7 of 51(13.7%) had no skin sensitization but suffered a clinical reaction during skin testing (mainly cough), and 6 of 51 (11.7%) exhibited immediate skin sensitization. Both skin sensitization and cough during testing were related to a higher use of adrenaline following immunization (P = .08 and P = .024, respectively). Further immunization with the BNT162b2 vaccine was recommended unless sensitization or severe reaction to previous immunization was evident. The latter were referred to be tested/receive the alternative AZD1222 vaccine. Ten patients underwent skin testing with AZD1222: 2 of 10 (20%) demonstrated skin sensitization to both vaccines; thus, 8 of 10 were immunized with the AZD1222, of which 2 of 8 (25%) had allergic reactions.ConclusionsImmediate allergic reactions to COVID-19 vaccines are rare but can be severe and reoccur. Intradermal testing with the whole vaccine may discriminate sensitized subjects, detect cross-sensitization between vaccines, and enable estimation of patients at higher risk.

Numerical analysis on the combustion characteristic of lithium-ion battery vent gases and the suppression effect

The combustion of Lithium-ion battery (LIB) vent gases plays key roles in determining LIB fire hazard. Previous studies analyze the combustion of LIB vent gases without consideration of electrolyte. This work studies the combustion characteristic of LIB vent gases with dimethyl carbonate (DMC) addition. The flammability limit, laminar burning velocity (LBV), flame temperature and heat production are explored. For different components of LIB vent gases, most of combustion parameters decrease or remain unchanged with addition of DMC. It demonstrates that the fire risk of LIB vent gases reduces with DMC addition. Moreover, the influences of H2O, C6F12O (Novec-1230) and POCH3(OCH3)2 (DMMP) on LIB vent gases flame are investigated. At Φ = 1.0, all three suppressants suppress the flame. The lowest and highest suppression efficiency are H2O and DMMP. At Φ = 0.45, Novec-1230 enhances combustion, but DMMP reduces LBV which is quite different from the enhancement effect on CH4/air flame. This is mainly because of the reducing of O free radical and heat production. The sensitivity and path reaction of DMMP indicate that phosphorus species play important roles in suppressing lean flame. This work could deepen understanding of LIB vent gases combustion dynamics and provide guidance for choosing appropriate suppressants of LIB fire.

A comprehensive experimental and kinetic modeling study of di-isobutylene isomers: Part 1

Di-isobutylene has received significant attention as a promising fuel blendstock, as it can be synthesized via biological routes and is a short-listed molecule from the Co-Optima initiative. Di-isobutylene is also popularly used as an alkene representative in multi-component surrogate models for engine studies of gasoline fuels. However, there is limited experimental data available in the literature for neat di-isobutylene under engine-like conditions. Hence, most existing di-isobutylene models have not been extensively validated, particularly at lower temperatures (< 1000 K). Most gasoline surrogate models include the di-isobutylene sub-mechanism published by Metcalfe et al. [1] with little or no modification. The current study is undertaken to develop a detailed kinetic model for di-isobutylene and validate the model using a wide range of relevant experimental data. Part 1 of this study exclusively focuses on the low- to intermediate temperature kinetics of di-isobutylene. An upcoming part 2 discusses the high-temperature model development and validation of the relevant experimental targets. Ignition delay time measurements for the di-isobutylene isomers were performed at pressures ranging from 15 – 30 bar at equivalence ratios of 0.5, 1.0, and 2.0 diluted in air and in the temperature range 650 – 900 K using two independent rapid compression machine facilities. In addition, measurements of species identified during the oxidation of these isomers were performed in a jet-stirred reactor and in a rapid compression machine. A detailed kinetic model for the di-isobutylene isomers is developed to capture the wide range of new experimental targets. For the first time, a comprehensive low-temperature chemistry submodel is included. The differences in the important reaction pathways for the accurate prediction of the oxidation of the two DIB isomers are compared using reaction path analysis. The most sensitive reactions controlling the ignition delay times of the DIB isomers under the pressure and temperature conditions necessary for autoignition in engines are identified.

Safety evaluation of the food enzyme chymosin from the genetically modified Aspergillus niger strain DSM32805.

The food enzyme chymosin (EC 3.4.23.4) is produced with the genetically modified Aspergillus niger strain by Chr. Hansen. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used in milk processing for cheese production and for the production of fermented milk products. Dietary exposure was estimated to be up to 0.09 mg total organic solids (TOS)/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level at the highest dose of 1,000 mg TOS/kg bw per day the highest dose tested, which when compared with the estimated dietary exposure, results in a margin of exposure of at least 10,600. Similarity of the amino acid sequence of the food enzyme to those of known allergens was searched and two matches with respiratory allergens were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood for this to occur is considered low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Safety evaluation of the food enzyme α-amylase from Cellulosimicrobium funkei strain AE-AMT.

The food enzyme α‐amylase (4‐α‐d‐glucan glucanohydrolase; EC 3.2.1.1) is produced with the non‐genetically modified Cellulosimicrobium funkei strain AE‐AMT by Amano Enzyme Inc. The food enzyme is free from viable cells of the production organism. It is intended to be used in starch processing for maltotriose production. Since residual amounts of total organic solids (TOS) are removed by purification steps applied during starch processing, the estimation of a dietary exposure is considered unnecessary. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level at the highest dose of 230 mg TOS/kg body weight (bw) per day. Similarity of the amino acid sequence of the food enzyme to those of known allergens was searched and nine matches were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood is considered low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Safety evaluation of the food enzyme mannan endo-1,4-β-mannosidase from the genetically modified Trichoderma reesei strain RF6232.

The food enzyme mannan endo‐1,4‐β‐mannosidase (1,4‐β‐d‐mannan mannanohydrolase; EC 3.2.1.78) is produced with the genetically modified Trichoderma reesei strain RF6232 by AB Enzymes GmbH. The genetic modifications do not give rise to safety concerns. The food enzyme was considered free from viable cells of the production organism and recombinant DNA. It is intended to be used in coffee processing, fruit and vegetable processing for juice production and for edible oil production. Since residual amounts of total organic solids (TOS) are removed during refined edible oil production by repeated washing, dietary exposure was calculated only for the remaining two food manufacturing processes. Dietary exposure to the food enzyme–TOS was estimated to be up to 0.09 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 100 mg TOS/kg bw per day, the lowest dose tested. This results in a margin of exposure above 1,100. A search for similarity of the amino acid sequence of the food enzyme to known allergens was made and one match was found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, in particular for individuals allergic to avocado, but the likelihood for this to occur is considered to be low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Safety evaluation of the native and thermolabile forms of the food enzyme mucorpepsin from Rhizomucor miehei strain MMR 164.

The food enzyme mucorpepsin (aspartic endopeptidase, EC 3.4.23.23) is produced with the non‐genetically modified microorganism Rhizomucor miehei strain MMR 164 by Takabio. The enzyme is chemically modified to produce a thermolabile form. The food enzyme is free from viable cells of the production organism. It is intended to be used in milk processing for cheese production. The dietary exposure to the food enzyme–total organic solids (TOS) was estimated to be up to 0.98 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1,320 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 1,300. Similarity of the amino acid sequence of the food enzyme to those of known allergens was searched and five matches were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions upon dietary exposure to this food enzyme cannot be excluded, but is considered low except for individuals sensitised to mustard proteins, but this risk will not exceed that of mustard consumption. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Safety evaluation of the thermolabile form of the food enzyme mucorpepsin from Rhizomucor miehei strain MMR 164.

The food enzyme mucorpepsin (aspartic endopeptidase, EC 3.4.23.23) is produced with the non‐genetically modified microorganism Rhizomucor miehei strain MMR 164. The enzyme is chemically modified by DuPont Nutrition Biosciences (now IFF) to produce a thermolabile form. The food enzyme is free from viable cells of the production organism. It is intended to be used in milk processing for cheese production. The dietary exposure to the food enzyme–total organic solids (TOS) was estimated to be up to 0.98 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1,320 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 1,300. Similarity of the amino acid sequence of the food enzyme to those of known allergens was searched and five matches were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions upon dietary exposure to this food enzyme cannot be excluded, but is considered low except for individuals sensitised to mustard proteins, but this risk will not exceed that of mustard consumption. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Safety evaluation of the food enzyme phosphoinositide phospholipase C from the genetically modified Bacillus licheniformis strain NZYM-DI.

The food enzyme phosphoinositide phospholipase C (1‐phosphatidyl‐1D‐myo‐inositol‐4,5‐bisphosphate inositoltrisphosphohydrolase, EC 3.1.4.11) is produced with the genetically modified Bacillus licheniformis strain NZYM‐DI by Novozymes A/S. The genetic modifications did not give rise to safety concerns. The production strain has been shown to qualify for the qualified presumption of safety (QPS) status. The food enzyme was co nsidered free from viable cells of the production organism and its DNA. It is intended to be used for degumming of fats and oils. Since residual amounts of total organic solids are removed during washing and purification steps applied during degumming, dietary exposure was not estimated. As the production strain B. licheniformis NZYM‐DI qualifies for the QPS approach to safety assessment and no issue of concern arose from the production process, no toxicological data were required. A search for similarity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure could not be excluded, but the likelihood for this to occur was considered low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

Safety evaluation of the food enzyme chymosin from the genetically modified Kluyveromyces lactis strain CIN.

The food enzyme chymosin (EC 3.4.23.4) is produced with the genetically modified Kluyveromyces lactis strain CIN by DSM Food Specialties B.V. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its recombinant DNA. It is intended to be used in milk processing for cheese production and for the production of fermented milk products. Dietary exposure was estimated to be up to 0.73 mg total organic solids (TOS)/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1,000 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, results in a margin of exposure of at least 1,300. Similarity of the amino acid sequence of the food enzyme to those of known allergens was searched for and four matches were found. The Panel considered that under the intended conditions of use the risk of allergic sensitisation and elicitation reactions by dietary exposure, although unlikely, cannot be excluded, particularly for individuals sensitised to cedar pollen allergens. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Mesoporous cellulose nanofibers-interlaced PEDOT:PSS hybrids for chemiresistive ammonia detection.

Chemiresistive ammonia (NH3) detection at room temperature is highly desired due to the unique merits of easy miniaturization, low cost, and minor energy consumption especially for portable and wearable electronics. In this regard, poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) has sparked considerable attention due to the benign room-temperature conductivity and environmental stability, but it is undesirably impeded by limited sensitivity and sluggish reaction kinetics. To overcome these, we incorporated cellulose nanofibers (CNF) into PEDOT:PSS via a facile blending. The constituent-optimized composite sensor displayed sensitive (sensitivity of ∼7.46%/ppm in the range of 0.2-3ppm), selective, and stable NH3 sensing at 25°C at 55% RH, with higher response and less baseline drift than pure PEDOT:PSS counterparts. Additionally, the response/recovery times (4.9s/5.2s toward 1ppm NH3) ranked the best cases of conducting polymers based NH3 sensors. The humidity involved more than twofold response enhancement indicated a huge potential in exhaled breath monitoring. Furthermore, we observed an excellent flexible NH3-sensing performance withbending-tolerant features. This work provides an alternative strategy for trace NH3 sensing with low power consumption, superfast reaction, and high sensitivity.

Safety evaluation of the food enzyme chymosin from the genetically modified Kluyveromyces lactis strain CHY.

The food enzyme chymosin (EC 3.4.23.4) is produced with the genetically modified Kluyveromyces lactis strain CHY by DSM Food Specialties B.V. It is intended to be used in milk processing for cheese production and for production of fermented milk products. Dietary exposure was estimated to be up to 0.69 mg total organic solids (TOS)/kg body weight (bw) per day in European populations. The production strain contains multiple copies of known antimicrobial resistance genes and consequently, it does not fully fulfil the requirements for the qualified presumption of safety (QPS) approach to safety assessment. However, considering the absence of viable cells and DNA from the production organism in the food enzyme, this is not considered to be a risk. As no other concerns arising from the microbial source and its subsequent genetic modification or from the manufacturing process have been identified, the Panel considered that toxicological tests were not needed for the assessment of this food enzyme. Similarity of the amino acid sequence of the food enzyme to those of known allergens was searched and four matches were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure, although unlikely, cannot be excluded, particularly for individuals sensitised to cedar pollen allergens. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Comparative Assessment of Diagnostic Performance of Cytochrome Oxidase Multiplex PCR and 18S rRNA Nested PCR.

Malaria elimination and control require prompt and accurate diagnosis for treatment plan. Since microscopy and rapid diagnostic test (RDT) are not sensitive particularly for diagnosing low parasitemia, highly sensitive diagnostic tools are required for accurate treatment. Molecular diagnosis of malaria is commonly carried out by nested polymerase chain reaction (PCR) targeting 18S rRNA gene, while this technique involves long turnaround time and multiple steps leading to false positive results. To overcome these drawbacks, we compared highly sensitive cytochrome oxidase gene-based single-step multiplex reaction with 18S rRNA nested PCR. Cytochrome oxidase (cox) genes of P. falciparum (cox-III) and P. vivax (cox-I) were compared with 18S rRNA gene nested PCR and microscopy. Cox gene multiplex PCR was found to be highly specific and sensitive, enhancing the detection limit of mixed infections. Cox gene multiplex PCR showed a sensitivity of 100% and a specificity of 97%. This approach can be used as an alternative diagnostic method as it offers higher diagnostic performance and is amenable to high throughput scaling up for a larger sample size at low cost.

Safety evaluation of the food enzyme chymosin from the genetically modified Aspergillus niger strain DSM 29546.

The food enzyme chymosin (EC 3.4.23.4) is produced with the genetically modified Aspergillus niger strain DSM 29546 by Chr. Hansen. The genetic modifications do not give rise to safety concerns. The food enzyme is free from viable cells of the production organism and its DNA. It is intended to be used in milk processing for cheese production and for the production of fermented milk products. Dietary exposure was estimated to be up to 0.52 mg total organic solids (TOS)/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 410 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, results in a margin of exposure of at least 790. Similarity of the amino acid sequence of the food enzyme to those of known allergens was searched and four matches were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure, although unlikely, cannot be excluded, particularly for individuals sensitised to cedar pollen allergens. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Safety evaluation of the food enzyme chymosin from the genetically modified Aspergillus niger strain DSM 29544.

The food enzyme chymosin (EC 3.4.23.4) is produced with the genetically modified Aspergillus niger strain DSM 29544 by Chr. Hansen. The genetic modifications do not give rise to safety concerns. The food enzyme was considered free from viable cells of the production organism and its DNA. It is intended to be used in milk processing for cheese production and for production of fermented milk products. Based on the maximum use levels, dietary exposure to the food enzyme total organic solids (TOS) was estimated to be up to 0.09 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not raise a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 84.1 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, results in a margin of exposure above 930. A search for similarity of the amino acid sequence of the food enzyme to known allergens was made and two matches with respiratory allergens were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood for this to occur is considered low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

Safety evaluation of the food enzyme α-amylase from the genetically modified Bacillus licheniformis strain NZYM-AY.

The food enzyme α‐amylase (4‐α‐d‐glucan glucanhydrolase; EC 3.2.1.1) is produced with the genetically modified Bacillus licheniformis strain NZYM‐AY by Novozymes A/S. The genetic modifications do not give rise to safety concerns. The food enzyme is considered free from viable cells of the production organism and its DNA. It is intended to be used in starch processing for the production of glucose syrup and other starch hydrolysates, and distilled alcohol production. Since residual amounts of total organic solids are removed by distillation and by the purification steps applied during the production of glucose syrups, dietary exposure estimation was considered unnecessary. The production strain of the food enzyme fulfils the requirements for the qualified presumption of safety (QPS) approach to safety assessment. As no other concerns arising from the manufacturing process have been identified, the Panel considers that toxicological tests are not needed for the assessment of this food enzyme. A search for similarity of the amino acid sequence of the food enzyme to known allergens was made and one match was found. The Panel considered that, under the intended conditions of use (other than distilled alcohol production) the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood for this to occur is considered to be low. Based on the data provided, the Panel concluded that this food enzyme did not give rise to safety concerns under the intended conditions of use.

Safety evaluation of the food enzyme mucorpepsin from Rhizomucor miehei strain DSM 29547.

The food enzyme mucorpepsin (EC 3.4.23.23) is produced with the non‐genetically modified Rhizomucor miehei strain DSM 29547 by Chr. Hansen. The food enzyme is free from viable cells of the production organism. It is intended to be used in dairy processing for cheese production. The dietary exposure to the food enzyme–total organic solids (TOS) was estimated to be up to 0.26 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 618 mg TOS/kg bw per day, the highest dose tested, which when compared with the estimated dietary exposure, results in a margin of exposure of at least 2,400. A search for similarity of the amino acid sequence of the food enzyme to known allergens was made and three matches were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded but is considered low except for individuals sensitised to mustard proteins, but this risk will not exceed that of mustard consumption. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

Safety evaluation of a food enzyme containing aspergillopepsin I and II from the Aspergillus niger var. macrosporus strain PTG8398.

The food enzyme with aspergillopepsin I (EC 3.4.23.18) and aspergillopepsin II (EC 3.4.23.19) activities is produced with a non‐genetically modified Aspergillus niger var. macrosporus strain PTG8398 by Meiji Seika Pharma Co., Ltd. The food enzyme was considered free from viable cells of the production organism. It is intended to be used in wine production. Based on the maximum use levels, dietary exposure to the food enzyme‐total organic solids (TOS) was estimated to be up to 0.14 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90‐day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 919 mg TOS/kg bw per day, the highest dose tested which, when compared with the estimated dietary exposure, results in a margin of exposure above 6,700. A search for similarity of the amino acid sequence of the food enzyme to known allergens was made and four matches with respiratory allergens were found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood for this to occur is considered low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

Particular qualities of laboratory approaches in complex diagnosis of human brucellosis

Brucellosis is an infectious particularly dangerous zoonotic disease caused by bacteria of the genus Brucella, among which B. melitensis, B. abortus, and B. suis have pathogenic potential, causing a severe and often chronic course of the disease.&#x0D; Laboratory diagnostics is crucial for the detection of human cases, since the clinical symptoms of human brucellosis are variable and nonspecific. Laboratory diagnosis of brucellosis is based on three different approaches: direct bacteriological method, indirect method using serological and allergic tests and direct express method in different formats of molecular polymerase chain reaction.&#x0D; Despite the accumulated experience of using serological tests and the highly sensitive polymerase chain reaction method, the isolation of Brucella culture is considered the gold standard in the laboratory diagnosis of brucellosis due to its clinical and epidemiological relevance. The currently available automated systems of the bacteriological method have increased its sensitivity and shortened the detection time of Brucella species.&#x0D; The main limitations of serological tests are the lack of general interpretation criteria, low specificity due to cross-reactions with other bacteria and low sensitivity at an early stage of the disease. At the same time, in Russia, serological tests account for more than 99% of all laboratory tests and remain the main diagnostic tool. This is due to their inexpensive and convenient use at the place of medical care in endemic areas and high negative prognostic value.&#x0D; Polymerase chain reaction in various formats of rapid tests diagnoses the DNA of the pathogen in a few hours with high sensitivity and specificity. Nevertheless, a positive polymerase chain reaction result requires careful interpretation and does not necessarily indicate an active infection.&#x0D; For the convenience of using diagnostic approaches to brucellosis in practical medicine and determining the activity of the infectious process, it is necessary to improve diagnostics and develop express methods.&#x0D; The review shows both the most routine and modern laboratory methods currently available for laboratory diagnosis of brucellosis.