Scientific Opinion on risk based control of biogenic amine formation in fermented foods

Discovery of Doenjang aging marker and metabolites alteration during long-term aging period: Targeted and untargeted metabolomic study

The aging of Doenjang enhances its flavor and complexity, making it highly valued by consumers. However, most previous studies have focused on aging periods of two years or less. Additionally, many analyzed samples are produced in laboratories or restricted to specific regions, limiting our understanding of long-term metabolic changes. In this study, we analyzed 49 traditional Doenjang samples aged from 1 to 30 years using CE-TOF/MS with both untargeted and targeted metabolomics to identify aging markers and metabolite profiles. The aging process significantly influenced the metabolites, increasing lactate, 13 amino acids, and four biogenic amines (histamine, tyramine, putrescine, and 2-phyenylethylamine), while reducing concentrations of arginine and tryptophan. These metabolic changes effectively distinguished short-term-aged Doenjang (1-2 years) from long-term-aged Doenjang (7-30 years). This integrated targeted and untargeted metabolomics provides better understanding into metabolic changes occurring during Doenjanbg maturation with practical applications for optimizing its safety and quality.

Use of Starmerella bacillaris and Hanseniaspora uvarum sequential fermentation with Saccharomyces cerevisiae to reduce putrescine and cadaverine and improve aroma profiles of wines

Putrescine and cadaverine are abundant in wine and pose a risk to the health of consumers. In this study, Starmerella bacillaris H18 and Hanseniaspora uvarum XJ15, with great ability to degrade putrescine and cadaverine, were evaluated through degradation characteristics, amine oxidase activity, environmental adaptability, and oenological performance. Results suggested that H18 and XJ15 exhibited a high ability to degrade >94 % of these two amines in must simulated medium, and the dynamics of amine degradation were mainly associated with the activities of monoamine oxidase and diamine oxidase. H18 and XJ15 sequential inoculation with Saccharomyces cerevisiae HL17 decreased levels of putrescine, cadaverine, and total amine, and increased the contents of ethyl acetate, 1-butanol, 3-methyl-, acetate, butanedioic acid, diethyl ester, α-ionone, and D-citronellol of Beimei and Cabernet Sauvignon wines, enhancing the typicality and complexity of floral and fruity aromas (OAV > 1.0). These results demonstrated the great potential of H18 and XJ15 in biogenic amine reduction and flavor improvement of wines, which is of great significance for the industrial production of wines with high quality and distinctive aroma characteristics.

Enrichment of the nutritional value of pea flour milling fractions through fermentation

In this work, pea flour and two milling fractions obtained by industrial-scale air classification were characterized and fermented by Lactiplantibacillus plantarum to increase their nutritional value. Scanning electron microscopy and chemical analysis revealed major differences in the morphology and composition of the flours. Protein-rich (43.7 %) fraction exhibits a few-fold higher mineral, spermidine (290 μg/g), but also a higher phytate (20.4 mg/g) content compared to starch-rich fraction. Flour type and inoculum majorly influenced the composition of the fermented product. In spontaneously fermented flours, biogenic amines accumulated up to 6.6 mg/g, which was the main drawback besides the large variations between batches, as confirmed by metagenomic analysis. Higher contents of lactic acid, free amino groups formed by proteolysis and gamma-aminobutyric acid were determined in inoculated fermentations of protein rich fraction, whereas a higher relative bioavailability of minerals was found in the inoculated starch-rich fraction, as the phytate content was reduced by 42 %.

Effect of LacBS/LacBP on biogenic amines degradation, physicochemical property, and flavor of Huangjiu

Enzymatic reduction of biogenic amines (BAs) in fermented foods is effective and safe, with minimal impact on food flavor and the fermentation process. This study aimed to efficiently reduce BAs in Huangjiu using laccase. LacBS, LacBP, and LacBV demonstrated extensive substrate specificity for BAs. Additionally, these three laccases were resistant to acidic conditions and stable across a wide ethanol range (3-24 % vol). The effect of temperature on the ability of the three laccases to degrade BAs in Huangjiu was investigated, revealing that LacBS and LacBP had higher total BAs degradation than LacBV at 30 °C + 80 °C. Furthermore, synergistic LacBS/LacBP (at a 1:1 ratio) treatment efficiently increased the degradation of BAs in Huangjiu Sp.4, Sp.8, and Sp.10 by 68.93 %, 72.1 %, and 75.37 %, respectively, without affecting the flavor profile or physicochemical properties. Synergistic laccase system for BAs degradation might be a potential "green technology" for industries of traditional fermented foods.

Influence of Autochthonous Lactic Acid Bacteria Cultures on the Microbiota and Biogenic Amine Production in Medium-Ripened Artisan Goat Cheese

This study evaluated the effects of adding the autochthonous cultures Limosilactobacillus mucosae CNPC007 (LM) and Lactiplantibacillus plantarum CNPC003 (LP), originally isolated from goat milk and goat cheese, respectively, on microbiological safety, microbiota composition (analyzed through 16S rRNA gene metataxonomic sequencing), and biogenic amine (BA) production in artisanal goat (coalho) cheese made from raw or pasteurized milk during 60 days of ripening at 10 °C. Six types of cheese were produced, varying in milk treatment (raw or pasteurized) and the presence or absence of LP or LM cultures. Adding either LP or LM significantly modulated the microbiota, favoring Streptococcus dominance and reducing overall bacterial diversity compared to non-inoculated cheeses. Raw milk cheeses with added autochthonous cultures exhibited a microbial profile like pasteurized cheeses, suggesting a homogenizing effect on the microbiome. Both cultures effectively reduced microbial load in raw milk cheeses after 20 days, reaching levels comparable to pasteurized cheeses by the end of ripening. Although BA concentrations increased over time, all samples remained within safe limits. Cheeses with LP addition exhibited lower BA levels, suggesting a modulating effect on their biosynthesis. Histamine concentrations were higher in raw milk cheeses with added cultures but remained well below hazardous levels. These findings suggest that incorporating either LP or LM strains is a promising strategy for enhancing the microbial safety and standardization of artisanal goat cheese while preserving its traditional characteristics.

Molecular characterization of histidine and tyrosine decarboxylating Enterococcus species isolated from some milk products

BACKGROUND

Fermented foods can cause adverse effects on human health because of the biogenic amines (BAs) accumulating through amino acid decarboxylation. This study investigated the presence of BAs including tyramine and histamine in 240 samples of some cheese and fermented milk samples using high-performance liquid chromatography. Another aim of this study is to isolate and identify Enterococcus spp. as the most important and frequent BA producer in the examined samples. The isolated Enterococcus spp. was investigated phenotypically for their capacity to produce amino acid decarboxylase enzyme using decarboxylase microplate assay, and genotypically through molecular detection of some genes encoding amino acid decarboxylation (tyrdc and hdc). Biogenic amines producing enterococci were then investigated for their antimicrobial resistance, biofilm production as well as their virulence determinants.

RESULTS

Tyramine and histamine could be detected in 86.7 and 87.9% of the investigated samples with 52.9% being contaminated with Enterococcus spp. Significant correlation between the incidence of Enterococci enterococci and BAs formed in the examined samples (P < 0.0001). tyrdc and hdc genes were detected in 85 and 5% of amino acid decarboxylating Enterococcus spp., respectively. A high percentage of Enterococcus isolates (57.5%) were multidrug-resistant and resistance against penicillin was widespread among isolates followed by tetracycline, vancomycin, erythromycin and linezolid. Also, 77.5% of the isolates were capable of forming biofilms and a highly significant correlation (P < 0.0001) was found between biofilm formation and multidrug resistance. The results showed that the rates of most virulence genes gelE, esp, ace, asa1, and cylA were 77.5. 47.5, 47.5, 35 and 7.5%, respectively, while the hyl gene was not detected in any isolates.

CONCLUSION

The study highlights the significant presence of BAs (TYM and HIS) in cheese and fermented milk samples, with a strong correlation between enterococci contamination and TYM production. The high prevalence of tyramine-producing Enterococcus species poses a notable public health concern especially with the high prevalence of multidrug-resistant, biofilm production and virulence in BAs producing Enterococcus spp. in dairy products, emphasizing the urgent need for improved antimicrobial stewardship among food producers and veterinarians to mitigate the risk of transferring resistant strains to humans.

Isolation and Characterization of β-Phenylethylamine-Producing Lactic Acid Bacteria from Dairy Products

β-phenylethylamine (PEA) is a neuroactive trace amine synthesized by the enzymatic decarboxylation of phenylalanine. PEA is involved in the improvement of mood and attention. Functional foods enriched in this compound could, therefore, be of interest to the food industry. PEA is produced by microbial activity in certain foods, but usually only in small amounts. The search for PEA-producing microorganisms with good technological properties is thus a pre-requisite if such functional foods are to be produced. This work reports the isolation of thirty-three PEA-producing bacterial strains from samples of different dairy products. They belong to the genus Enterococcus, and the species Levilactobacillus brevis. Identified strains of Enterococcus durans were then selected for technological characterization. Some of them showed properties of interest. In this species, PEA was determined to be produced via the action of tyrosine decarboxylase, encoded by the gene tdcA. This implies that, apart from PEA, a concomitant production of tyramine, a toxic biogenic amine, was observed.

The association of seasonal dietary shift with fecal metabolome and microbiota in the captive Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis)

The gut microbiota can act as a buffer against changes in energy and food availability and adapt plastically to fluctuations in the host's diet. However, it is unknown how changes in the gut microbiome with the seasons impact microbial metabolism and the accessibility of nutrients to hosts. The study utilized 16S rRNA and UHPLC-MS/MS approaches to examine seasonal fecal metabolome variations in the captive Yangtze finless porpoises (YFPs) to determine if these variations are linked to nutrient intake or gut microbiome composition changes. The YFPs were mostly fed a frozen and live fish diet, with different food intakes yearly. We found that gut microbial diversity remained constant, but community structure varied seasonally. Firmicutes and Cyanobacteria were higher in winter, Actinobacteria in spring and fall, and proteobacteria in summer. The genus Paeniclostridium was significantly higher in the spring season, Romboutsia and Clostridium_sensu_stricto_13 were significantly higher in the summer, while Terrisporobacter and Macrococcus were significantly higher in the fall group. The study reported that seasonal dietary variation significantly impacted the fecal metabolome by affecting the metabolism, including energy, amino acid, carbohydrate, and nucleotide metabolism of the captive YFP. Moreover, significant correlations between metabolome and microbiome were found, and these correlations may indicate that the captive YFP has adapted to cope with dietary variations and enhance energy acquisition. These findings improve our knowledge of the link between microbiota, diet, metabolites, and the physiology of the host and suggest that gut microbial populations may adapt continuously to changes in diet.

Effects of epigallocatechin gallate on microbial communities of rainbow trout fillets during ice storage and identification of biogenic amines-producing bacteria

Biogenic amines-producing bacteria were isolated from rainbow trout fillets and their biogenic amines production ability was investigated. The effects of epigallocatechin gallate (EGCG) on the microbial communities of rainbow trout fillets were also investigated. Fifteen (15) strains of biogenic amines-producing bacteria were isolated from rainbow trout fillets. Pseudomonas psychrophila and Shewanella baltica produced putrescine (73.97 mg/mL) and histamine (48.66 mg/mL), respectively. The high-throughput sequencing results indicated Proteobacteria were the dominant phyla of the both control group and the EGCG treated groups. At the genus level, Shewanella spp. and Pseudomonas spp. were the dominating bacteria in the control group, while Pseudomonas spp. were the dominant bacteria in the EGCG treated groups. EGCG can obviously decrease bacterial diversity of rainbow trout fillets, which was mainly reflected in the relative abundance of Shewanella spp. This study provides microbial insights into controlling the quality of rainbow trout fillets during ice storage.

Histamine and biogenic amines in Vietnamese traditional fish sauce by hydrophilic interaction liquid chromatography-tandem mass spectrometry

A straightforward method for the determination of histamine and other biogenic amines in Vietnamese traditional fish sauce was developed, avoiding a time-consuming derivatisation step. This resulted in the application of hydrophilic interaction in combination with liquid chromatography-tandem mass spectrometry (HILIC-MS/MS). The characteristics of the analytical method, such as linearity, limit of detection (LOD), limit of quantification (LOQ), repeatability, stability, and matrix effects were systematically investigated. The validated method was successfully applied to analyse 8 biogenic amines in 15 Vietnamese traditional fish sauce samples, as well as 10 broth samples directly collected from the fermentation tanks. Among the eight investigated biogenic amines, histamine was found in all analysed samples, in some at high levels. However, in traditional fish sauce samples collected from supermarkets histamine levels were lower than the maximum level as set by European Union regulations.

A Fluorescence/Colorimetric Synergistic-Enhanced Type-I Heterostructured MOF@QDs for Both Multi-Depth Food-Freshness Prediction and Extra Preservation

Spoiled food has significantly impacted the global economy and public health, which increases worldwide concern about monitoring and preserving food freshness. Herein, a multi-functional type-I heterojunction (Eu@ZMC) is designed by europium metal-organic framework (EuMOF), zinc oxide quantum dots (ZnO QDs), and chlorogenic acid (CGA). Eu@ZMC achieves ratiometric fluorescent/colorimetric sensing of pH and biogenic amines to detect freshness. Besides, a paper-based platform (PEu@ZMC) is prepared and can detect histamine with the LOD of 0.0142 and 0.0136 µg mL-1 in fluorescent and colorimetric modes, respectively. An advanced OR/NOT-gate logic device is further constructed to distinguish freshness into three levels (fresh, less fresh, and spoiled). This dual-mode sensor is synergistic-enhanced by the energy transfer triggered by ZnO QDs-promoted colorimetry and the type-I heterostructure of fluorescent EuMOF and ZnO QDs. The release of low-toxic zinc ions inhibits various bacterial growth, including Salmonella typhimurium. According to raw fish evaluation, Eu@ZMC not only effectively monitors spoilage externally and internally aligning with a commercial kit, but also reduces spoilage speed, which cannot be achieved through the classical detection strategy. This original work provides a simple, convenient, and reliable method for multi-depth and real-time visual food monitoring with extract freshness preservation, contributing to economic benefits and human health assurance.

Biogenic amines degradation ability of Saccharomyces cerevisiae I45 and Pichia sp. NW5 & LB60 and their application in beer fermentation

Biogenic amines (BAs) are abundant in craft beer and pose toxicological risks to consumers. Certain microbes have shown potential for degrading BAs. This study, for the first time, used beer as a fermentation system to screen three yeast strains: Saccharomyces cerevisiae I45, Pichia kluyveri NW5, and Pichia terricola LB60, which effectively reduced BA levels in stout beer. The degradation rates for tryptamine by S. cerevisiae I45, tyramine by P. kluyveri NW5, and putrescine by P. terricola LB60 were 55.76 %, 41.75 %, and 36.53 %, respectively. After mixed fermentation, the total BAs degradation rate in the stout beer was 48.81 %, and the highest degradation rates of the representative bioamines tryptamine and putrescine were 40.52 % and 50.96 %, respectively. Additionally, glycerol yield and ester content were significantly increased, without negatively impacting the beer's volatile aroma components, while enhancing characteristic aromas like rose and tropical fruit. These findings provide a theoretical basis and technical guidance for improving the safety and sensory quality of craft beer.

Extraction and analytical approaches for the determination of post-food processing major carcinogens: A comprehensive review towards healthier processed food

Different food processing methods, e.g. fermentation, grilling, frying, etc., to improve food sensory attributes or shelf-stability are typically employed in different cuisines worldwide. These methods may illicit in-situ health-hazardous chemicals via thermal or enzymatic-mediated processes or chemical interactions with food preservatives. This review provides a comparative overview of the occurrence, extraction, and determination of the major food carcinogens such as nitrosamines (NAs), biogenic amines (BAs), heterocyclic aromatic amines (HAAs), polycyclic aromatic hydrocarbons (PAHs), ethyl carbamate (EC), and malondialdehyde (MDA). Their carcinogenicity levels vary from group 1 (carcinogenic to humans) e.g. benzo[a]pyrene, group 2A (probably carcinogenic to humans) e.g. N-nitrosodiethylamine, group 2B (possibly carcinogenic to humans) e.g. chrysene or group 3 (non-classifiable as carcinogenic to humans) e.g. MDA. Chromatography-based methods are the most predominant techniques used for their analysis. LC-MS is widely used for both volatile/non-volatile NAs, HAAs, BAs, and EC, whereas GC-MS is applied more for volatile NAs, PAHs and MDA.

Production and transformation of biogenic amines in different food products by the metabolic activity of the lactic acid bacteria

Protein-rich diets often contain high quantities of biogenic amines (BAs), notably histamine and tyramine, which pose substantial health hazards owing to their toxicity. BAs are primarily produced by the microbial decarboxylation of free amino acids. Lactic acid bacteria (LAB) can either produce BAs using substrate-specific decarboxylase enzymes or degrade them into non-toxic compounds using amine-degrading enzymes such as amine oxidase and multicopper oxidase. Furthermore, LAB may inhibit BA-producing microbes by generating bioactive metabolites, including organic acids and bacteriocins. This paper thoroughly explores the processes underlying BA production and degradation in LAB, with a focus on the diversity of enzymes involved. Metabolic mapping of LAB strains at the genus and species levels reveals their involvement in BA metabolism, from production to degradation. The phylogenetic-based evolutionary relatedness of BA-producing and BA-degrading enzymes among LAB strains sheds light on their functional adaptability to various metabolic needs and ecological settings. These findings have significant practical implications for establishing better microbial management strategies in food production, particularly through strategically using starter or bioprotective cultures to reduce BA buildup. By highlighting the evolutionary and metabolic diversity of LAB, this review helps to optimize industrial fermentation processes, improve food safety protocols, and advance future research and innovation in BA management, ultimately protecting consumer health and supporting regulatory compliance.

Biogenic Amines in White Brined Cheeses

In the current study, a comprehensive analysis of biogenic amines in white brined cheeses was conducted. BAs may accumulate in food in high concentrations via the activities of microorganisms that produce decarboxylation enzymes. Neither tryptamine, phenylethylamine, nor spermidine was detected in the monitored cheese samples. Biogenic amines were detected in 20 samples, with tyramine and spermine being the most abundant, particularly in Feta cheeses, where tyramine concentrations exceeded 100 mg/kg in three samples. In 25% of the tested cheeses, total concentration of all the monitored biogenic amines and polyamines exceeded the level of 100 mg/kg, which may be considered of toxicological significance to sensitive persons. Decarboxylase activity was identified in 94 isolates, including significant producers such as Levilactobacillus brevis and Enterococcus durans. The correlation between high total microbial counts and lactic acid bacteria suggests that these microorganisms play a critical role in biogenic amine production. Our findings highlight the importance of monitoring specific microbial populations to mitigate biogenic amine risks in cheese production.

The development of a whole-cell biosensor enabled the identification of agmatine-producing Hafnia spp. in cheese

Agmatine, the decarboxylation product of arginine, is the precursor of putrescine - a harmful biogenic amine (BA) - that can accumulate in dairy products via bacterial metabolism involving the agmatine deiminase (AGDI) pathway. This first requires agmatine be produced via the decarboxylation of arginine and it remains unknown which microorganisms are responsible for this prior decarboxylation step. In addition, agmatine, as other BA, plays different physiological roles including those of co-transmitter and neuromodulator. Preclinical and clinical studies have shown agmatine to have a neuroprotective effect, rendering it of therapeutic interest being agmatine-producing bacteria proposed as psychobiotics. The identification of BA-producing microorganisms is based on the rise in pH due to the consumption of H+ during such decarboxylation reactions. However, in the detection of agmatine-producing microorganisms in cheese, this would lead to false positives since many bacteria possess arginine deiminase activity; this produces ornithine and ammonium from arginine, which also increases the pH. To overcome this problem, a whole-cell biosensor based on a previously developed agmatine-inducible transcription system was designed, and a protocol optimized for the successful identification of agmatine-producing microorganisms in cheese. The application of this protocol in cheese samples allowed for the isolation of agmatine-producing microorganisms identified as Hafnia spp. and unravels, for first time, the capacity of Hafnia paralvei to produce agmatine. This finding evidence the potential role of Hafnia spp. in putrescine accumulation in dairy products.

The Health Impact of Cocoa from Cultivation to the Formation of Biogenic Amines: An Updated Review

Cocoa and chocolate are known for their health benefits, which depend on factors like cocoa variety, post-harvest practices, and manufacturing processes, including fermentation, drying, roasting, grinding, and refining. These processing methods can influence the concentration and bioavailability of bioactive compounds, such as polyphenols that are linked to cardiovascular health and antioxidant effects. Recent scientific research has led to the development of cocoa-based products marketed as functional foods. However, despite the growing interest in the functional potential of cocoa, the literature lacks crucial information about the properties of different varieties of cocoa and their possible implications for human health. Moreover, climate change is affecting global cocoa production, potentially altering product composition and health-related characteristics. In addition to polyphenols, other compounds of interest are biogenic amines, due to their role and potential toxic effects on human health. Based on toxicological data and recent research on the complex relationship between biogenic amines and cocoa fermentation, setting limits or standards for biogenic amines in cocoa and chocolate could help ensure product safety. Finally, new trends in research on biogenic amines in chocolate suggest that these compounds might also be used as quality markers, and that product formulation and process conditions could change content and diversity of the different amines.

Comorbidity of Histamine Intolerance and Polyvalent Allergy: A Case Report and Literature Review

Background/Objectives: Histamine intolerance is becoming a critical medical problem across numerous clinical specialties, due to the absence of a standardized diagnostic and therapeutic strategy to manage patients with a suspicion of or diagnosis of this condition. Histamine intolerance is a type of non-immune food hypersensitivity, characterized by heterogenous etiologies and a very broad range of symptoms. The condition is the result of an imbalance between the amount of histamine accumulated within the body and the body's systemic ability to degrade it. In regard to the diagnostics of histamine intolerance, the need to preliminarily exclude other potential conditions associated with increased histamine levels in the blood has been highlighted. The co-occurrence of allergies and histamine intolerance is not uncommon, and the similarity of the clinical manifestations can lead to diagnostic, as well as therapeutic, difficulties. This paper details the diagnostic and clinical workflow for a patient with histamine intolerance and polyvalent allergy comorbidity, with the aim being to help outline a protocol that may be helpful to clinicians managing patients with histamine intolerance. Case Presentation: This article presents the case of a 30-year-old patient with a polyvalent allergy and multimorbidity (allergic rhinitis, asthma, a food allergy, and eosinophilic esophagitis), with comorbid histamine intolerance. Due to the violent and severe symptoms, including facial erythema, urticaria, pruritus, abdominal pain, and tachycardia, experienced after meals, the patient received intramuscular epinephrine injections three times a week. The diagnostic protocol and the course of therapeutic management are presented. Conclusions: The diagnosis of histamine intolerance is difficult due to the high variability and heterogeneity of clinical symptoms in individual patients. Many studies on the issue recommend ruling out an allergic background in terms of the complaint. However, the possibility of the symptoms of an IgE-dependent allergy overlapping with those of histamine intolerance should be taken into account in every case. This is particularly important in patients presenting with an atypical and severe course of allergic diseases. The clinical case presented herein may be helpful for the daily practice of allergologists and physicians with other specialties, as an example of multimorbidity with both allergic and non-allergic backgrounds.

Characterization of ornithine decarboxylase with histidine decarboxylase activity in natural histidine decarboxylase gene deletion Enterobacter hormaechei RH3

Histamine is predominantly produced in sausages via the decarboxylation of histidine by bacteria. Furthermore, histamine-producing bacteria usually possess the enzyme histidine decarboxylase (hdc). Enterobacter hormaechei RH3 isolated from sausages exhibited significant levels of histamine production despite the absence of hdc. In this study, we elucidated the previously unidentified mechanism underlying histamine production by RH3. We identified an enzyme, NehdX-772, exhibiting the hdc activity from the cell lysate supernatant of RH3, which was annotated as ornithine decarboxylase. The optimal activity of NehdX-772 was recorded at 35 °C and pH 6.0, and it could tolerate a salt concentration of 2.5% (w/v) NaCl. Moreover, artificial inoculation revealed that NehdX-772 was synthesized at significant levels in sausages, leading to an increase in histamine levels. The discovery of NehdX-772 explains the underlying mechanism of histamine production by RH3 and can be applied to decrease histamine production in sausages.

Tryptamine accumulates in cheese mainly via the decarboxylation of tryptophan by lactic acid bacteria

Few microorganisms are known to decarboxylate L-tryptophan, thereby producing tryptamine, a neuromodulator biogenic amine (BA) that can accumulate in cheese. Since lactic acid bacteria (LAB) are largely responsible for the production of other BA in this product, it was hypothesised that they would also be the main agents of tryptamine production. Using a rapid test based on the natural fluorescence of tryptamine, thousands of bacterial isolates from several cheese samples were screened. Only 1.4% of all isolates (43 out of 2982) were able to synthesise tryptamine and secrete it into the culture medium, highlighting the rarity of tryptophan-decarboxylating activity in this food source. Moreover, over 90% of these isolates were identified as belonging to Loigolactobacillus coryniformis, Enterococcus durans, or the Latilactobacillus sakei group (all lactic acid bacteria). No strain belonging to either of the first two species has previously been described as a tryptamine producer. Strains of the non-LAB species Staphylococcus epidermidis, Klebsiella pneumonia and Corynebacterium flavescens were also identified as tryptamine producers for the first time. Further typification of the producers based on their tryptamine yield was performed, and their potential applications as technological adjuncts for use in the dairy industry, as cell factories, or even as psychobiotics, are discussed.

Characterization of key off-odor compounds in grass carp cube formed during room temperature storage by molecular sensory science approach

Flavor is a significant factor in determining the popularity of freshwater fish. However, freshwater fish can easily spoil during storage, producing an unpleasant odor. Little research has determined the changes in key off-odor compounds (OOCs) in freshwater fish during storage. In this study, quantitation and odor activity value (OAV) calculations revealed that 19 odorants were important volatile odor compounds in fresh, spoilage, and serious spoilage GCC. Recombination and omission experiments verified that (E)-2-hexenal, acetoin, N,N-dimethyl-benzenamine, trimethylamine (TMA), and ammonia were the key OOCs in spoilage GCC. Additional key OOCs in serious spoilage GCC were cyclohexane isothiocyanato, butylated hydroxytoluene, putrescine, cadaverine and histamine compared to those of spoilage GCC. Correlation analysis showed that 12 amino acids and 10 fatty acids played important roles in the formation of key OOCs. This study provides a theoretical basis for a comprehensive understanding of the formation of key OOCs in GCC during room temperature storage.

Study Protocol for a Prospective, Unicentric, Double-Blind, Randomized, and Placebo-Controlled Trial on the Efficacy of a Low-Histamine Diet and DAO Enzyme Supplementation in Patients with Histamine Intolerance

BACKGROUND/OBJECTIVES

Histamine intolerance is primarily caused by a deficiency in the diamine oxidase (DAO) enzyme at the intestinal level. The reduced histamine degradation in the gut leads to its accumulation in plasma, thereby causing multiple clinical manifestations, such as urticaria, diarrhea, headache, dyspnea, or tachycardia, among others. The dietary management of this food intolerance consists of the follow-up of a low-histamine diet, often combined with DAO supplementation. To date, around twenty studies have investigated the effectiveness of these dietary strategies in reducing the frequency and/or intensity of symptoms, with promising results. However, the limitations of these studies (small patient cohort, lack of control group, and short dietary intervention periods) highlight the need for more ambitiously designed research. Therefore, the main objective of this prospective, unicentric, double-blind, randomized, and placebo-controlled trial is to evaluate the efficacy of a low-histamine diet and/or DAO supplementation over a three-month period in improving symptoms of histamine intolerance. Additionally, the impacts of these dietary strategies on the intestinal microbiota composition, urinary profile of histamine metabolites, serum DAO activity, and plasma histamine levels will be assessed throughout the intervention.

METHODS

The trial will enroll 400 patients who will be randomly assigned to one of two groups: the intervention group, which will follow a low-histamine diet, or the control group, which will maintain their habitual dietary habits. Within each of these groups, participants will be further divided into four subgroups to receive either exogenous DAO enzyme supplementation (from porcine or plant sources, with the latter administered at two different dosages) or a placebo. Therefore, a total of eight distinct intervention groups will be considered. The comparison of these groups will allow the evaluation of the individual effects of the low-histamine diet or DAO enzyme supplementation, as well as their possible synergistic effect.

RESULTS

The results of this study should help to improve dietary recommendations for histamine-intolerant patients and ultimately enhance their quality of life.

Essential Oils Against Spoilage in Fish and Seafood: Impact on Product Quality and Future Challenges

The preservation of fish and seafood represents a significant challenge for the food industry due to these products' high susceptibility to microbial spoilage. Essential oils (EOs), classified as Generally Recognized as Safe (GRAS), have become a natural alternative to synthetic preservatives due to their antimicrobial and antioxidant properties. This review aims to analyze the specific potential of EOs in extending the shelf life of fish and seafood products, offering a natural and effective preservation solution. It provides a detailed overview of EOs applications and mechanisms, highlighting their role in controlling spoilage microorganisms while maintaining product quality. The main methods of EOs application include immersion, spraying, and pipetting, with antimicrobial effectiveness influenced by factors such as concentration, exposure time, and food characteristics like chemical composition and biofilms. Direct EOs application shows challenges that can be countered by exploring nanoemulsion technology as an effective strategy to enhance EOs stability and controlled release, maximizing their preservation impact. Additionally, coatings made from chitosan, gelatin, Farsi gum, and carrageenan, combined with EOs such as oregano, clove, and thyme have shown efficacy in preserving species like rainbow trout, mackerel, and shrimp. However, the commercial feasibility of using EOs in fish preservation depends on consumer acceptance and regulatory compliance. This review offers valuable insights for the industry and researchers by highlighting the practical applications and commercial challenges of EOs in seafood products, underscoring the importance of consumer acceptance and regulatory adherence for market viability.

Biogenic amines and bacterial spoilage in Plant-Based grill sausage alternatives

Vegan and vegetarian diets are increasing in popularity. Consequently, the supply and demand of plant-based meat alternatives has increased steadily over the past few years. However, scientific research on spoilage processes for such products is still inadequate as compared to research on traditional meat products. In traditional meat products, biogenic amines are prominent spoilage markers and potential sources of food toxicity, especially for people sensitive to biogenic amines. Plant-based meat alternatives are manufactured to mimic the taste, look, texture, and nutritional value of meat, and they have a protein-rich basis. It is therefore hypothesized that biogenic amines could be markers for spoilage in such products as well. Further analysis of their presence and concentrations and comparison to conventional meat products is necessary. If biogenic amines are lower in plant-based meat alternatives, these products are possibly better suited for consumption by people with biogenic amine sensitivities. A simple and rapid extraction method, followed by HILIC-MS/MS separation and detection was therefore developed as a first step and validated for nine biogenic amines in plant-based meat alternatives. This method showed a strong linear correlation between amine concentration and detector response, high accuracy, and precision (< 12 %), as well as high sensitivity, as proven by the lowest limits of quantification (i.e., the lowest concentration within the calibration model) of 1 mg/kg for all analytes, which also compares well with other methods. Subsequently, as part of a pilot spoilage study, the method was applied to one vegetarian and nine vegan grill sausage alternatives during a period of 32 days of open-package storage at refrigerator temperature. Correlations with the results of microbiological testing of the same samples, as well as with the storage time were investigated. However, the results of the correlation analysis showed that biogenic amines are not suitable as spoilage indicators for plant-based meat alternatives, as almost no increase in biogenic amines was identified during the spoilage study for all the samples investigated. Differences in the microbiota of conventional meat products versus plant-based meat alternatives, as well as possibly lower concentrations of free amino acids, are proposed as reasons for biogenic amines not being similarly prevalent, and consequently, not being suitable spoilage markers in plant-based meat alternatives. However, as spoilage of the analyzed products was evident, both via sensory assessment and appearance of mold growth, further targeted and non-targeted research on potential spoilage markers for plant-based meat alternatives is required in the future.

Identification of technological/metabolic/environmental profiles associated with cheeses accumulating the neuroactive compound tryptamine

Tryptamine is a neuromodulator of the central nervous system. It is also a biogenic amine, formed by the microbial decarboxylation of L-tryptophan. Tryptamine accumulation in cheese has been scarcely examined. No studies are available regarding the factors that could influence its accumulation. Determining the tryptamine content and identifying the factors that influence its accumulation could help in the design of functional tryptamine-enriched cheeses without potentially toxic concentrations being reached. We report the tryptamine concentration of 300 cheese samples representing 201 varieties. 16% of the samples accumulated tryptamine, at between 3.20 mg kg-1 and 3012.14 mg kg-1 (mean of 29.21 mg kg-1). 4.7% of cheeses accumulated tryptamine at higher levels than those described as potentially toxic. Moreover, three technological/metabolic/environmental profiles associated with tryptamine-containing cheese were identified, as well as the hallmark varieties reflecting each. Such knowledge could be useful for the dairy industry to control the tryptamine content of their products.

Provolone del Monaco PDO cheese: Lactic microflora, biogenic amines and volatilome characterization

One commercial production run of Provolone del Monaco - a long-ripened pasta filata cheese - was followed up to the end of ripening for a total of 20 samples. 371 LAB isolates were subject to genetic characterization followed by 16S rRNA gene sequencing. The dominant species were Lacticaseibacillus casei/paracasei (19.4 %), Streptococcus macedonicus (19.1 %) and Enterococcus faecalis (13.2 %). Strains were screened for features of technological interest or safety relevance. Tyramine-producing cultures were quite common, above all within enterococci. By MALDI TOF Mass Spectrometry, one Lactococcus lactis and one Enterococcus faecium strain proved to be bacteriocin producers. Four further cheese wheels from the same production run at 623 days of ripening were evaluated for volatile organic compounds, biogenic amines, and bacterial community by metagenomic sequencing. Three individual wheel samples shared a rather similar microbiome with Lactobacillus delbrueckii and Streptococcus thermophilus as the most represented species, while the fourth wheel appeared wholly different being dominated by Lentilactobacillus buchneri and St. infantarius. Additionally, this sample had the greatest content of biogenic amines and a different VOCs composition. Given the variance seen among cheese wheels processed and ripened under the same conditions, the search for adjunct cultures in the production of this cheese seems to be of utmost importance.

A comprehensive study on the autochthonous microbiota, volatilome, physico-chemical, and morpho-textural features of Montenegrin Njeguški cheese

The present study aims to deepen the knowledge of the microbiota, gross composition, physico-chemical and morpho-textural features, biogenic amines content and volatilome of Njeguški cheese, one of the most popular indigenous cheeses produced in Montenegro. Cheese samples were collected in duplicate from three different batches produced by three Montenegrin artisan producers. For the first time, the microbiota of Njeguški cheese was investigated using both culture-dependent techniques and metagenomic analysis. Coagulase positive staphylococci viable counts were below the detection limit of the analysis (<1 log cfu g-1). Salmonella spp., Listeria monocytogenes and staphylococcal enterotoxins were absent. However, relatively high viable counts of Enterobacteriaceae, Escherichia coli, Pseudomonadaceae and eumycetes were detected. Metataxonomic analysis revealed a core microbiome composed of Lactococcus lactis, Streptococcus thermophilus, Debaryomyces hansenii, and Kluyveromyces marxianus. Furthermore, the detection of opportunistic pathogenic yeasts such as Magnusiomyces capitatus and Wickerhamiella pararugosa, along with the variable content of biogenic amines, suggests the need for increased attention to hygienic conditions during Njeguški cheese production. Significant variability was observed in humidity (ranging from 38.37 to 45.58 %), salt content (ranging from 0.70 to 1.78 %), proteins content (ranging from 21.42 to 25.08 %), ash content (ranging from 2.97 to 4.05 %), hardness, springiness, and color among samples from different producers. Gas chromatography-mass spectrometry analysis showed a well-defined and complex volatilome profile of the Njeguški cheese, with alcohols (ethanol, isoamyl alcohol, phenetyl alcol), esters and acetates (ethyl acetate, ethyl butanoate, isoamyl acetate), ketones (acetoin, 2-butanone), and acids (acetic, butanoic, hexanoic acids) being the main chemical groups involved in aroma formation. This research will provide new insights into the still poorly explored identity of Njeguški cheese, thus serving as a first baseline for future studies aimed at protecting its tradition.

Association of Ultraprocessed Foods Intake with Untargeted Metabolomics Profiles in Adolescents and Young Adults in the DONALD Cohort Study

BACKGROUND

High consumption of ultraprocessed foods (UPFs) continues to draw significant public health interest because of the associated negative health outcomes. Metabolomics can contribute to the understanding of the biological mechanisms through which UPFs may influence health.

OBJECTIVES

To investigate urine and plasma metabolomic biomarkers of UPF intake in adolescents and young adults.

METHODS

We used data from the Dortmund Nutritional and Anthropometric Longitudinally Designed study to investigate cross-sectional associations of UPF intake with concentrations of urine metabolites in adolescents using 3d weighed dietary records (3d-WDR) and 24-h urine samples (n = 339), and associations of repeatedly assessed UPF intake with concentrations of circulating plasma metabolites in young adults with 3-6 3d-WDRs within 5 y preceding blood measurement (n = 195). Urine and plasma samples were analyzed using mass spectrometry-based metabolomics. Biosample-specific metabolite patterns (MPs) were determined using robust sparse principal components analysis. Multivariable linear regression models were applied to assess the associations of UPF consumption (as a percentage of total food intake in g/d) with concentrations of individual metabolites and MP scores.

RESULTS

The median proportion of UPF intake was 22.0% [interquartile range (IQR): 12.3, 32.9] in adolescents and 23.2% (IQR: 16.0, 31.6) in young adults. We identified 42 and 6 UPF intake-associated metabolites in urine and plasma samples, respectively. One urinary MP, "xenobiotics and amino acids" [β = 0.042, 95% confidence interval (CI): 0.014, 0.070] and 1 plasma MP, "lipids, xenobiotics, and amino acids" (β = 0.074, 95% CI: 0.031, 0.117) showed positive association with UPF intake. Both patterns shared 29 metabolites, mostly of xenobiotic metabolism.

CONCLUSIONS

We identified urine and plasma metabolites associated with UPF intake in adolescents and young adults, which may represent some of the biological mechanisms through which UPFs may influence metabolism and health.

Exposure assessment and semi-quantitative risk analysis of histamine in tuna and tuna-like fish from Indonesia

This study aimed to investigate histamine exposure associated with consumption of fresh tuna and tuna-like species in West Java, and to estimate risk of Scombroid Fish Poisoning (SFP) in Indonesia. A range of species, including tuna (Thunnus spp.), bullet tuna (Auxis sp.), and skipjack (Katsuwonus pelamis) were collected from local markets and fish landing sites. Subsequently, histamine concentrations were determined using NMR analysis and exposure was calculated in mg/day for toddlers, children, and adults. The results showed that skipjack had the highest histamine exposure for all age groups, followed by bullet and regular tuna. The highest EDI for histamine was from skipjack consumption, accounting for 38.67; 37.77 and 20.74 percentage of exposure for toddlers, children and adults, respectively. These values are below the defined thresholds levels (ARfD), indicating no potential risk of acute health effect. Cooked bullet tuna and skipjack were estimated to cause similar illnesses, accounting for 6-7 cases per 100,000 individuals, which was higher than cooked tuna at 1-2 cases per 100,000 individuals. Considering the preparation of raw tuna in restaurants following Good Hygienic Practices (GHP), the predicted annual cases decreased significantly to 4-5 cases per million individuals. This risk estimation only considered histamine levels in fresh fish, without including data from fish preparation. Therefore, further studies were recommended to estimate the risk level in raw/fresh tuna and similar species before consumption.

Comprehensive Safety Assessment of Lacticaseibacillus paracasei subsp. paracasei NTU 101 Through Integrated Genotypic and Phenotypic Analysis

Probiotics, as defined by the World Health Organization, are live microorganisms that, when consumed in sufficient quantities, provide health benefits to the host. Although some countries have approved specific probiotic species for use in food, safety concerns may still arise with individual strains. Lacticaseibacillus paracasei subsp. paracasei NTU 101 (NTU 101), isolated from the gut of healthy infants, has demonstrated various probiotic effects and shown safety in a prior 28-day animal feeding study. To further verify its safety and mitigate potential risks, we performed a comprehensive genotypic and phenotypic safety evaluation in accordance with the European Food Safety Authority guidelines for safety assessment through whole genome sequencing and related literature. In this research, minimum inhibitory concentration testing identified NTU 101's resistance to chloramphenicol; however, subsequent gene analysis confirmed no associated risk of resistance. Assessments of safety, including biogenic amine content, hemolytic activity, mucin degradation, and D-lactic acid production, indicated a low level of risk. Additionally, a repeated-dose 90-day oral toxicity study in Sprague-Dawley rats revealed no toxicity at a dose of 2000 mg/kg body weight, further supporting the strain's safety for consumption. Based on these comprehensive analyses, NTU 101 is considered safe for regular consumption as a health supplement.

Coinoculation of autochthonous starter cultures: A strategy to improve the flavor characteristics and inhibit biogenic amines of Harbin dry sausage

The effects of separately coinoculating Lactiplantibacillus plantarum S8 (LP) with Staphylococcus carnosus L8 (LP + SC), Pichia kudriavzevii M6 (LP + PK), and S. carnosus L8 and P. kudriavzevii M6 (LP + SC + PK) on the flavor characteristics and biogenic amines (BAs) production in Harbin dry sausages were investigated. The coinoculated sausages exhibited higher free amino acids (FAAs) content than the noninoculated and LP sausages. Moreover, inoculated dry sausages exhibited lower BA contents (174.45, 239.43, 190.24, and 206.7 mg/kg for the LP, LP + SC, LP + PK, and LP + PK + SC sausages, respectively) than the noninoculated sausage (339.73 mg/kg). Meanwhile, the LP + PK and LP + SC + PK sausages had the highest contents of esters (996.70 μg/kg) and alcohols (603.46 μg/kg), respectively. A sensory evaluation demonstrated that the LP + SC + PK sausage had the highest fermented odor and the lowest fatty odor. Pearson correlation analysis revealed that FAAs were correlated with most key volatile compounds and BAs. This study provides new insights into flavor development and BA inhibition in dry sausages through coinoculation.

Do the biogenic amines ethylamine, ethanolamine and methylamine reach toxic concentrations in foods?

Ethylamine, ethanolamine and methylamine are biogenic amines (BA) - active metabolites that, despite having important biological functions, may accumulate at toxic concentrations in certain foods. Very little information exists on the toxicity of these BA in this context. This study provides new insights into their cytotoxicity with respect to a human intestinal epithelial cell line, as assessed using real-time cell analyzer technology. A preliminary evaluation of the cytotoxic mode of action was also performed. The present results show that only ethylamine was cytotoxic for these cells at food concentrations. These new data should help establish legal limits for these BA in foods.

Insights into Genomic Characteristics and Biogenic Amine Degradation Potential and Mechanisms: A Strain of Pediococcus acidilactici Sourced from Doubanjiang

The control of excess biogenic amines (BAs) is crucial for the sustainable development of fermented foods. This study aimed to screen endogenous functional strains in Doubanjiang with the capacity to degrade BAs and to elucidate their application potential. Pediococcus acidilactici L-9 (PA), which was confirmed as a safe strain by phenotypic and genotypic analyses, exhibited an efficient degradation ability on BAs, particularly regarding tyramine. Notably, the degradation of tyramine was maintained at 24.03-50.60% at different temperatures (20-40 °C), pH values (4.0-9.0), and NaCl concentrations (3-18%, w/v). Additionally, genomic data revealed the presence of the laccase-coding gene, which was demonstrated to play a pivotal role in BA degradation by heterologous expression. Further, molecular docking results indicated that the degradation of BA by laccase is closely linked to the electron transfer pathway formed by the substrate and key amino acid residues. Finally, the degradation of tyramine by PA remained within the range of 8.19-64.19% under the simulated system with 6-12% salinity. This study provided valuable insights into the safety of PA and its potential degradation capacity on BAs, particularly in mitigating tyramine accumulation, which could improve the quality of Doubanjiang and other fermented foods.

The Factors Influencing the Concentration of Histamine in Jarred Baby Foods Containing Fish, Considering Evaluation of Daily Histamine Intake

Histamine is one of the biogenic amines produced naturally in the human body, but also in foods, especially those rich in protein. Exogenous and endogenous histamine is subject to degradation in vivo, but in the case of sensitive groups, including children, these degradation processes may be less intense, resulting in adverse health effects from histamine excess. The aim of the study was to determine the histamine content in jarred baby foods containing fish, taking into account the selected product characteristics and storage conditions. The study included 140 meals with added fish, intended for infants and young children, from 5 leading manufacturers available in Poland. The infant meals were analyzed on the day of opening, after 24 h and 48 h of storage in the refrigerator and at room temperature. Histamine concentration was determined by ELISA. The THQ was calculated from the EDI values for histamine. Histamine was present in all analyzed baby foods. On the day of opening, the products had a lower content of this monoamine (Me = 2.59 mg/kg), which increased systematically during storage. Samples taken at 2 °C after 48 h showed an average histamine content of 4.4 mg/kg, while products stored at 22 °C at the same time showed a 1.8-fold higher concentration of this monoamine (Me = 7.9 mg/kg). Dishes containing tuna and sea fish had higher histamine levels on average than those containing pollock. The storage conditions of the children's food had a significant effect on histamine concentration. The level of histamine in baby foods was related to the amount and type of fish in certain products. The results indicate the need for increased awareness of the risks associated with histamine, especially in a group of people with increased sensitivity to this amine, which may include infants and young children.

Visual detection of biogenic monoamines based on amine oxidase-peroxidase coupling reaction using ascorbic acid as H2O2 scavenger

This study represents a visual detection for total biogenic monoamines with naked eye as a simple and rapid semi-quantitative method for biogenic amine monitoring. The equivalent reaction of H2O2 with ascorbic acid resulted in color development by an amine oxidase-peroxidase coupling reaction in the samples containing the biogenic monoamines higher than the subjected ascorbic acid by 10 μM. Upon employing the commercial doenjang extracts as a model food, an additional heating step was requested, and the expected ranges for the biogenic monoamines from 360 to 480 μM covered the real contents of the samples (360.2-407.3 μM). Therefore, this visual detection method makes it possible to decide with naked eye whether the sample contains the biogenic monoamines higher than the ascorbic acid supplemented as much as a control level on manufacturing sites without instrumental analysis.

A Comprehensive Review on the Biogenic Amines in Cheeses: Their Origin, Chemical Characteristics, Hazard and Reduction Strategies

Most of the biogenic amines are naturally found in fermented foods as a consequence of amino acid decarboxylation. Their formation is ascribable to microorganisms (starters, contaminants and autochthonous) present in the food matrix. The concentration of these molecules is important for food security reasons, as they are involved in food poisoning illnesses. The most frequent amines found in foods are histamine, putrescine, cadaverine, tyramine, tryptamine, phenylethylamine, spermine and spermidine. One of the most risk-prone foods are cheeses, mostly ripened ones, which could easily accumulate amines due to their peculiar manufacturing process and ripening. Cheeses represent a pivotal food in our diet, providing for nutrients such as amino acids, calcium, vitamins and others; thus, since they are widely consumed, it is important to evaluate the presence of toxic molecules to avoid consumers' poisoning. This review aimed to gather general information on the role of biogenic amines, their formation, the health issues and the microorganisms and processes that produce/reduce them, with a focus on their content in different types of cheese (from soft to hard cheeses) and the biotic and abiotic factors that influence their formation or reduction and concentration. Finally, a multivariate analysis was performed on the biogenic amine content, derived from data available in the literature, to obtain more information about the factors influencing their presence in cheeses.

The effects of Lactiplantibacillus plantarum 3-19 and Pediococcus pentosaceus 18-1 on preventing the accumulation of biogenic amines and promoting the production of volatile organic compounds during sour meat fermentation

Lactic acid bacteria (LAB) are frequently used in meat fermentation, and mixed stater cultures are reported to perform better than single ones. Lactiplantibacillus plantarum 3-19 and Pediococcus pentosaceus 18-1 were chosen from 28 sour-meat-origin strains to examine the effects of single and combined inoculation on sour meat quality. Natural fermentation was used as a control to investigate changes in pH, water activity (aw), amino acid nitrogen (AN), texture, microbial diversity, and volatile organic compounds (VOCs) during fermentation. The pH and aw of each inoculation group were significantly decreased, and AN content was significantly increased. The inoculation of P. pentosaceus 18-1 significantly reduced putrescine, cadaverine, and tryptamine content (p < 0.05), while the inoculation of Lpb. plantarum 3-19 significantly reduced cadaverine amounts (p < 0.05). At the fermentation endpoint, the total biogenic amines content in the C group was 992.96 ± 14.07, which was 1.65, 2.57, and 3.07 times higher than that in the Lp, Pe, and M groups, respectively. The mixed inoculation group combined the advantages of both strains and decreased total biogenic amines most significantly. At the end of fermentation, the VOCs in C, Lp, Pe, and M groups were 10.11, 11.56, 12.45, and 13.39 times higher than those at the beginning of fermentation. Inoculation promoted the production of key VOCs (OAV > 2000) such as heptanal, octanal, and (E)-2-nonanal. The mixed inoculation group had the highest variety and content of VOCs and the highest content of the above key VOCs, significantly enhancing its fruity, floral, ester, and other aromas. Sensory evaluation indicated that the M group had the best overall acceptability. Finally, it was suggested that a combination of Lpb. plantarum 3-19 and P. pentosaceus 18-1 is a novel and efficient starter culture for processing sour meat since they lower the amounts of biogenic amines in the meat and promote the production of VOCs.

Multicopper Oxidase from Lactobacillus hilgardii: Mechanism of Degradation of Tyramine and Phenylethylamine in Fermented Food

Elevated levels of biogenic amines (BAs) in fermented food can have negative effects on both the flavor and health. Mining enzymes that degrade BAs is an effective strategy for controlling their content. The study screened a strain of Lactobacillus hilgardii 1614 from fermented food system that can degrade BAs. The multiple copper oxidase genes LHMCO1614 were successfully mined after the whole genome protein sequences of homologous strains were clustered and followed by homology modeling. The enzyme molecules can interact with BAs to stabilize composite structures for catalytic degradation, as shown by molecular docking results. Ingeniously, the kinetic data showed that purified LHMCO1614 was less sensitive to the substrate inhibition of tyramine and phenylethylamine. The degradation rates of tyramine and phenylethylamine in huangjiu (18% vol) after adding LHMCO1614 were 41.35 and 40.21%, respectively. Furthermore, LHMCO1614 demonstrated universality in degrading tyramine and phenylethylamine present in other fermented foods as well. HS-SPME-GC-MS analysis revealed that, except for aldehydes, the addition of enzyme treatment did not significantly alter the levels of major flavor compounds in enzymatically treated fermented foods (p > 0.05). This study presents an enzymatic approach for regulating tyramine and phenylethylamine levels in fermented foods with potential applications both targeted and universal.

A Survey on Potentially Beneficial and Hazardous Bioactive Compounds in Cocoa Powder Samples Sourced from the European Market

Cocoa (Theobroma cacao, L.) represents an important market that gained relevance and became an esteemed commodity thanks to cocoa powder, chocolate, and other related products. This work analyzed 59 cocoa powder samples from the European market. Three distinct subgroups were identified: organic or conventional, alkalized or not alkalized, and raw or roasted processing. The impact of the technological process on their pH, color, and compositional traits, as well as their content of biogenic amines and salsolinol, was evaluated. The phenolic fraction was also investigated through both common and emerging methods. The results depict that the influence of the agronomical practices (organic/conventional) did not significantly (p < 0.05) affect the composition of the cocoa powders; similarly, the roasting process was not a determinant of the compounds traced. On the other hand, the alkalinization process greatly impacted color and pH, no matter the cocoa's provenience or obtention or other processes, also resulting in reducing the phenolic fraction of the treated samples. Principal component analysis confirmed that the alkali process acts on pH, color, and phenolic composition but not on the content of other bioactive molecules (biogenic amines and salsolinol). All the samples were safe, while the alkalized powders saw a great reduction in beneficial biocompounds. A novel strategy could be to emphasize on the label whether cocoa powder is non-alkalized to meet the demand for more beneficial products.

A Novel Herbal Composition Alleviates Functional Constipation, Reduces Gastrointestinal Transit Time, and Improves Bowel Function in Adults: A Double-Blind, Randomized Clinical Study

BACKGROUND AND OBJECTIVE

A recent proof-of-concept pilot clinical study has demonstrated that consumption of CL18100F4, a proprietary herbal blend of Withania somnifera root and Abelmoschus esculentus fruit extracts, significantly relieved the participants from functional constipation and improved their quality of life. The objective of the present randomized, double-blind, placebo-controlled study was to reevaluate the efficacy and tolerability of CL18100F4 in a larger number of subjects.

METHODS

Male and female subjects (n = 135; age: 25-60 years), selected through Rome-IV criteria for functional constipation, were randomized into placebo and 300 or 500 mg of CL18100F4 groups and supplemented daily over 60 consecutive days. The primary efficacy outcome measure was Patient Assessment of Constipation-Symptoms (PAC-SYM), evaluated at baseline and on days 7, 30, and 60 of supplementation. The secondary efficacy parameters included Patient Assessment of Constipation-Quality of Life (PAC-QOL), Gastrointestinal Symptom Rating Scale (GSRS) scores, Gastrointestinal Transit Time (GIT), and Complete Spontaneous Bowel Movement (CSBM). Serum levels of Interleukin (IL)-6, IL-10, cortisol, gastrin, serotonin, Diamine oxidase (DAO), and Zonulin were measured.

RESULTS

CL18100F4 supplementation significantly (p < 0.001) reduced the PAC-SYM, PAC-QOL, GSRS scores, and GIT and improved CSBM scores. CL18100F4 significantly improved (p < 0.001) sleep quality and decreased depression and anxiety symptoms in the participants. Notably, relief in constipation symptoms and improved gastrointestinal (GI) function were reported starting from day 7. Furthermore, CL18100F4 supplementation significantly (p < 0.001) increased the serum levels of IL-10, DAO, serotonin, gastrin, reduced IL-6, cortisol, and Zonulin. No major adverse events were observed. Participants' vital signs, hematology, clinical biochemistry, and urinalysis parameters were within the normal ranges.

CONCLUSION

The present investigation demonstrates that CL18100F4 is tolerable and efficacious in relieving functional constipation, alleviating GI dysfunction, and improving associated non-GI factors in male and female adults.

Measurement of diamine oxidase (DAO) during low-histamine or ordinary diet in patients with histamine intolerance

BACKGROUND/OBJECTIVES

Quantification of diamine oxidase (DAO) concentrations in serum has been proposed as an adjunctive diagnostic modality for the evaluation of histamine intolerance (HIT). Limited empirical data exist concerning the influence of dietary patterns on DAO levels.

SUBJECTS/METHODS

In the context of a prospective study employing a crossover design, 18 individuals diagnosed with HIT were randomized to initiate either a low histamine diet (LHD) or a conventional mixed diet (MXD). Serum DAO concentrations were measured at the commencement of the study and following each dietary phase. A control group underwent analogous DAO assessments without imposition of dietary constraints.

RESULTS

During the time when a diet restricted in histamine was implemented, noticeable differences in changes in DAO levels did not become apparent when compared to the changes observed during the mixed (MXD) phase. Specifically, among the group, 10 of the 18 patients exhibited elevated DAO values subsequent to the LHD regimen, while the remaining eight displayed either reduced or unchanging DAO levels. The prevalence of elevated DAO levels in the LHD group did not differ significantly from that observed in the control group during the MXD phase. Additionally, during the LHD phase, patients reported a significant reduction in gastrointestinal and cutaneous symptoms.

CONCLUSIONS

This prospective investigation underscores the enduring utility of a histamine-restricted diet, coupled with structured dietary reintroduction, as an efficacious diagnostic approach for individuals presenting with suspected food-related histamine hypersensitivity. Notably, the measurement of DAO levels appears to furnish only a limited capacity to discern dietary-induced fluctuations. Notwithstanding, the dynamics of DAO alteration do not appear to exhibit a discernible association with specific dietary patterns, a finding consistent across both patient and control groups.

Variation of Cyclodextrin (CD) Complexation with Biogenic Amine Tyramine: Pseudopolymorphs of β-CD Inclusion vs. α-CD Exclusion, Deep Atomistic Insights

Tyramine (TRM) is a biogenic catecholamine neurotransmitter, which can trigger migraines and hypertension. TRM accumulated in foods is reduced and detected using additive cyclodextrins (CDs) while their association characteristics remain unclear. Here, single-crystal X-ray diffraction and density functional theory (DFT) calculation have been performed, demonstrating the elusive pseudopolymorphs in β-CD inclusion complexes with TRM base/HCl, β-CD·0.5TRM·7.6H2O (1) and β-CD·TRM HCl·4H2O (2) and the rare α-CD·0.5(TRM HCl)·10H2O (3) exclusion complex. Both 1 and 2 share the common inclusion mode with similar TRM structures in the round and elliptical β-CD cavities, belong to the monoclinic space group P21, and have similar herringbone packing structures. Furthermore, 3 differs from 2, as the smaller twofold symmetry-related, round α-CD prefers an exclusion complex with the twofold disordered TRM-H+ sites. In the orthorhombic P21212 lattice, α-CDs are packed in a channel-type structure, where the column-like cavity is occupied by disordered water sites. DFT results indicate that β-CD remains elliptical to suitably accommodate TRM, yielding an energetically favorable inclusion complex, which is significantly contributed by the β-CD deformation, and the inclusion complex of α-CD with the TRM aminoethyl side chain is also energetically favorable compared to the exclusion mode. This study suggests the CD implications for food safety and drug/bioactive formulation and delivery.

The Impact of Plant Additives on the Quality and Safety of Ostrich Meat Sausages

Ostrich meat is an interesting alternative to poultry or beef due to its nutritional value. The addition of three plant species (hot peppers, acerola, Schisandra chinesis) was suggested as a method to improve the quality, safety, and consumer acceptance of sausages prepared from ostrich meat. A series of microbiological and chemical analyses (including, inter alia, content of biogenic amines, heavy metals, and bioactive compounds) of the products as well as their sensory evaluation was performed to verify this claim. The microflora of all sausages was dominated by lactic acid bacteria. The biggest threat to consumers' health could be connected to the presence of biogenic amines formed through the enzymatic activity of lactic acid bacteria. The sausages with plant additives had better antioxidative and anti-inflammatory properties and lower fat oxidation-these features were correlated with the presence of vitamin C. Sausages with plant additives had a higher acceptability in terms of taste and smell.

Bacteriocins against biogenic amine-accumulating lactic acid bacteria in cheese: Nisin A shows the broadest antimicrobial spectrum and prevents the formation of biofilms

Cheese is a food in which toxic concentrations of biogenic amines (BA) may be reached, mainly as a consequence of the decarboxylation of determined amino acids by certain lactic acid bacteria (LAB). To maintain the food safety of cheese, environmentally friendly strategies are needed that specifically prevent the growth of BA-producing LAB and the accumulation of BA. The bacteriocins produced by LAB are natural compounds with great potential as food biopreservatives. This work examines the antimicrobial potential of 7 bacteriocin-containing, cell-free supernatants (CFS: coagulin A-CFS, enterocin A-CFS, enterocin P-CFS, lacticin 481-CFS, nisin A-CFS, nisin Z-CFS and plantaricin A-CFS) produced by LAB against 48 strains of the LAB species largely responsible for the accumulation of the most important BA in cheese, that is, histamine, tyramine, and putrescine. Susceptibility to the different CFS was strain-dependent. The histamine-producing species with the broadest sensitivity spectrum were Lentilactobacillus parabuchneri (the species mainly responsible for the accumulation of histamine in cheese) and Pediococcus parvulus. The tyramine-producing species with the broadest sensitivity spectrum was Enterococcus faecium, and Enterococcus faecalis and Enterococcus hirae were among the most sensitive putrescine producers. Nisin A-CFS was active against 31 of the 48 BA-producing strains (the broadest antimicrobial spectrum recorded). Moreover, commercial nisin A prevented biofilm formation by 67% of the BA-producing, biofilm-forming LAB strains. These findings underscore the potential of bacteriocins in the control of BA-producing LAB and support the use of nisin A as a food-grade biopreservative for keeping BA-producing LAB in check and reducing BA accumulation in cheese.

EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA), Turck D, Bohn T, Castenmiller J, De Henauw S, Hirsch‐Ernst KI, Maciuk A, Mangelsdorf I, McArdle HJ, Naska A, Pentieva K, Siani A, Thies F, Tsabouri S, Vinceti M, Aguilera‐Gómez M, Cubadda F, Frenzel T, Heinonen M, Maradona MP, Neuhäuser‐Berthold M, Siskos A, Poulsen M, Schlatter JR, van Loveren H, Azzollini D, Knutsen HK. Safety of Acheta domesticus powder as a Novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on Acheta (A.) domesticus powder as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The main components of the NF are protein, fat and dietary fibre (chitin). The Panel notes that the concentration of contaminants in the NF depends on the occurrence levels of these substances in the insect feed. The Panel further notes that there are no safety concerns regarding the stability of the NF if the NF complies with the proposed specification limits during its entire shelf-life. The NF has a high protein content, although the true protein content is overestimated when using the nitrogen-to-protein conversion factor of 6.25 due to the presence of non-protein nitrogen from chitin. The applicant proposed to use the NF as food ingredient in a number of food products. The target population proposed by the applicant is the general population. Considering the composition of the NF and the proposed conditions of use, the consumption of the NF is not nutritionally disadvantageous. The panel notes that no safety concerns arise from the toxicological information of A. domesticus. The panel considers that the consumption of the NF might trigger primary sensitisation to A. domesticus proteins and may cause allergic reactions in subjects allergic to crustaceans, mites and molluscs. Additionally, allergens from the feed may end up in the NF. The panel concludes that the NF is safe under the proposed uses and use levels.

Pharmacological profile of agmatine: An in-depth overview

Agmatine, a naturally occurring polyamine derived from arginine via arginine decarboxylase, has been shown to play multifaceted roles in the mammalian body, impacting a wide range of physiological and pathological processes. This comprehensive review delineates the significant insights into agmatine's pharmacological profile, emphasizing its structure and metabolism, neurotransmission and regulation, and pharmacokinetics and function. Agmatine's biosynthesis is highly conserved across species, highlighting its fundamental role in cellular functions. In the brain, comparable to established neurotransmitters, agmatine acts as a neuromodulator, influencing the regulation, metabolism, and reabsorption of neurotransmitters that are key to mood disorders, learning, cognition, and the management of anxiety and depression. Beyond its neuromodulatory functions, agmatine exhibits protective effects across various cellular and systemic contexts, including neuroprotection, nephroprotection, cardioprotection, and cytoprotection, suggesting a broad therapeutic potential. The review explores agmatine's interaction with multiple receptor systems, including NMDA, α2-adrenoceptors, and imidazoline receptors, elucidating its role in enhancing cell viability, neuronal protection, and synaptic plasticity. Such interactions underpin agmatine's potential in treating neurological diseases and mood disorders, among other conditions. Furthermore, agmatine's pharmacokinetics, including its absorption, distribution, metabolism, and excretion, are discussed, underlining the complexity of its action and the potential for therapeutic application. The safety and efficacy of agmatine supplementation, demonstrated through various animal and human studies, affirm its potential as a beneficial therapeutic agent. Conclusively, the diverse physiological and therapeutic effects of agmatine, spanning neurotransmission, protection against cellular damage, and modulation of various receptor pathways, position it as a promising candidate for further research and clinical application. This review underscores the imperative for continued exploration into agmatine's mechanisms of action and its potential in pharmacology and medicine, promising advances in the treatment of numerous conditions.

Construction of SERS output-signal aptasensor using MOF/noble metal nanoparticles based nanozyme for sensitive histamine detection

Herein, a signal output SERS aptasensor for Histamine (HA) detection is designed. MIL-100(Fe) was loaded with gold nanoparticles (AuNPs) to form composite nanozyme MIL-100(Fe)@AuNPs, which was used in the reaction system TMB/H2O2. Silver nanoparticles (AgNPs) were synthesized as "amplifier" for the SERS signal of ox TMB. After nucleic acid functionalization, the two parts were assembled to form the multifunctional substrate with both high catalytic and SERS efficiency. In the detection system, the specific binding effect of HA aptamer toward HA induced a decrease in the assembly of AgNPs on MIL-100(Fe)@AuNPs which caused a decrease in ox TMB SERS signals. The linear relation of HA ranged from 10-11 M to 5 × 10-3 M with LOD as low as 3.9 × 10-12 M. Recovery ratio in fermented soybean products (94.42-105.75 %) proved the real sample applicability. The fabricated SERS aptasensor will provide technical support for the safety during food processing and storage.

Investigation of Biogenic Amine Levels and Microbiological Activity as Quality Markers in Some Dairy and Fish Products in Food Markets in the Kingdom of Saudi Arabia

This study aimed to verify the presence of biogenic amines (BAs) and evaluate the microbiological activity of some food samples collected from retail stores in the Kingdom of Saudi Arabia. A total of thirty-five dairy and fish products were collected and analyzed for BAs, including putrescine (PUT), cadaverine (CAD), spermidine (SPE), histamine (HIS), spermine (SPR), and tyramine (TYR), as well as for total colony count (TCC), lactic acid bacteria (LAB), Enterobacteriaceae, yeast and mold (Y and M), coliforms, and aerobic sporulation count (ASF). The thin layer chromatography (TLC) method was used in the analytical methodology to identify the BAs. The results showed the presence of BAs in all dairy products, but their concentration did not exceed the maximum permissible limit, which in contrast was established by the Food and Drug Administration (FDA) at 10 mg/100 g. The amounts of BAs in fish products varied significantly. All fish product samples contained levels of BAs below the permissible limit. Results of an independent study also indicated potential toxicity at levels of BAs (>10 mg/100 g) in Egyptian herring. Enterobacteriaceae and the coli group were present in higher concentrations in the Egyptian herring samples, whereas other samples (particularly frozen shrimp) showed increased TCC levels with a higher concentration of histamine-producing bacteria. From a consumer safety perspective, this study also indicated that food samples generally contained acceptable levels of BAs. In conclusion, there is a need to improve and standardize food quality and hygiene practices during production and storage to ensure human safety and prevent HIS formation.

Technological and Enzymatic Characterization of Autochthonous Lactic Acid Bacteria Isolated from Viili Natural Starters

Viili, a Finnish ropy fermented milk, is traditionally manufactured through spontaneous fermentation, by mesophilic lactic acid bacteria and yeast-like fungi, or back-slopping. This study evaluated four natural viili starters as sources of lactic acid bacteria for dairy production. Back-slopping activation of the studied viili samples was monitored through pH and titratable acidity measurements and enumeration of mesophilic lactic acid bacteria. Sixty lactic acid bacteria isolates were collected, molecularly identified, and assayed for acidification performance, enzymatic activities, production of exopolysaccharides (EPSs), presence of the histidine decarboxylase (hdcA) gene of Gram-positive bacteria, and production of bacteriocins. A neat predominance of Lactococcus lactis emerged among the isolates, followed by Enterococcus faecalis, Enterococcus faecium, Enterococcus durans, Enterococcus lactis, and Lactococcus cremoris. Most isolates exhibited proteolytic activity, whereas only a few enterococci showed lipase activity. Five isolates identified as L. cremoris, L. lactis, and E. faecalis showed a good acidification performance. Most of the isolates tested positive for leucine arylamidase, whereas only one E. durans and two L. lactis isolates were positive for valine arylamidase. A few isolates also showed a positive reaction for beta-galactosidase and alpha- and beta-glucosidase. None of the isolates produced EPSs or bacteriocins. The hdcA gene was detected in five isolates identified as L. lactis and E. faecium. A few L. cremoris and L. lactis isolates for potential use as starter or adjunct cultures for dairy processing were finally identified.

Assessment of biogenic amines in commercial tuna fish: Influence of species, capture method, and processing on quality and safety

This study investigated the influence of species, capture method, chilling, and freezing on the quality and variations in biogenic amines of Thunnus tonggol and Thunnus albacares. Samples were collected from different sources, including fisheries ports, cold rooms, and canning factories. The results indicated that canned fish had significantly higher levels of biogenic amines, especially histamine, compared to raw fish from ports and cold rooms. However, all canned samples complied with the FDA regulation of 50 mg/kg for histamine content. Canning led to a substantial increase in total amines, with histamine being the predominant amine in most groups. Putrescine was present in all samples, with the highest levels found in canned tuna made from frozen yellow-fin tuna captured using drift gillnetting. Canned samples also exhibited higher cadaverine levels compared to raw tuna. Storage conditions, capture method, and tuna species were found to significantly affect tuna quality and biogenic amines formation.