Effects of potassium lactate on sensory attributes,bacterial community succession and biogenic amines formation in Rugao ham

To deepen the understanding in the effect of potassium lactate on the sensory quality and safety of Rugao ham,sensory attributes,physicochemical parameters,total volatile basic nitrogen(TVBN),microorganism community and biogenic amines of Rugao ham manufactured with different potassium lactate levels(0%,0.5%,1%,2%)were investigated;the relationship between microbial community and the formation of TVBN and biogenic amines was further evaluated.With the increase of potassium lactate from 0%to 2%,the increased sensory scores and the decreased total aerobic bacterial count and TVBN were observed;the abundance of Staphylococcus increased,while the content of Halomonas decreased.LDA effect size(LEf Se)and correlations analysis showed that Staphylococcus equorum and Lactobacillus fermentum could be the key species to improve sensory scores and decrease biogenic amines and TVBN.Metabolic pathway analysis further showed that amino acids metabolism and nitrogen metabolism were mainly involved in decreasing TVBN and biogenic amines in the treatment of 2%potassium lactate.

Effects of biogenic amines on the testicular development in mud crabs Scylla serrata

The regulation of three biogenic amines over the reproductive neuroendoerine activity of the male Scylla serrata was investigated by in vivo injection and in vitro incubation. The testicular index, the ratio of the mature sections in testes, and the ratio of Type B cells in androgenic gland were taken as the quantitative indexes. The in vivo injections indicated that： 5-HT can significantly promote the testicular development and the secretion of the androgenic gland in S. serrata; DA can inhibit the testicular development, but no influence on the secretion of the androgenic gland was found; no significant difference was observed between the OA-injected group and the concurrent control group. In vitro incubations showed that： 5-HT can stimulate the secretion of the brain and the thoracic ganglia, thus accelerating that of the androgenic gland; however, neither OA nor DA showed any significant influence on the secretion of the brain and the thoracic ganglionic mass. As to the optic ganglia, the three biogenic amines hardly have any effect on its secretion. It is the first time to report the regulation of biogenic amines over the reproductive neuroendocrine of male crustaceans through vitro experiments. Results corroborate that 5-HT activates the brain and the thoracic ganglia to secret GSH first, then promote the testicular development through the activity of the androgenic gland.

HPLC Determination of the Major Non-protein Amino Acids and Common Biogenic Amines in Lathyrus sativus Using a Novel Extraction Method

An assay is presented for simultaneously determining 5 biogenic amines and the major non-protein amino acids: the toxin β-N-oxalyl-L-α,β-diaminopropanoic acid (β-ODAP), its isomer α-ODAP and homoarginine in Lathyrus sativus extracts using the HPLC system after derivatization with para-nitrobenzyloxycarbonyl chloride (PNZ-Cl). However, it is more worthy of noting that this paper also describes a new extraction method using 0.2 mol/L HClO4. The new method has some advantages: shorter extraction-time, simultaneous extraction of free amino acids and polyamines, better inhibiting the isomerization of β-ODAP to α-ODAP, and so on.

Significance of Biogenic Amines in Foods and Their Reduction Methods

The term ＂biogenic amines＂ defines decarboxylation products such as histamine, putrescine, serotonin, tyramine, phenylethylamine, tryptamine and also aliphatic polyamines. They can be detected in both raw and processed foods. In the recent years, there is a great interest in biogenic amines as they are associated with quality, safety and freshness of some foods, particularly fermented foods. The presence of biogenic amines in foods can also be used as an indicator of hygienic quality. Biogenic amines also cause health hazards due to their toxic effects especially in sensitive individuals. It is therefore important to control and reduce the biogenic amines. The reduction can be brought about by the use of high pressure, irradiation, packaging, additives, starter cultures and by reduction of decarboxylase activity and temperature. This review summarizes the significance, function, occurrence and formation of biogenic amines in different foods and their reduction by different methods.

Biogenic Amines as Biomarkers for Neurotoxicity

There has been a surge of interest over the past several years in the use of neurochemical endpoints to contribute to our understanding of the mechanism of action of neurotoxicants. In our present presentation, two biogenic amine systems were selected as examples of biomarkers for neurotoxicity. To investigate these neurochemical endpoints, two prototype neurotoxicants were evaluated in experimental animals. One agent, reserpine, was used to assess developmental neurotoxicity and administered prenatally, while the other, MDMA, was used in the adult animal. The neurochemical biomarkers measured were dopamine, serotonin, and their metabolite (DOPAC and 5-HIAA) concentrations by HPLC/EC and dopamine receptor binding by radioligand receptor techniques. A review of the background, experimental design, and results are presented in this article. Our findings indicate that components of the biogenic amine systems can be used as sensitive neurochemical biomarkers of neurotoxicity. These neurochemical biomarkers can be correlated with neuropathological and behavioral biomarkers to aid in the understanding of mechanisms of neurotoxicity.

Biogenic Amines Profile of Serbian Traditional Sausage in Relation to Raw Material and Production Conditions

Petrovska klobasa is a traditional dry fermented sausage produced in the Autonomous Province of Vojvodina. Formation of nine hiogenic amines was determined in three sausage groups produced from hot deboned （A1） and cold meat （B1, B3） during drying and ripening in traditional room （A1, B1） and in industrial ripening chamber （B3）. Dansyl chloride derived amines were analysed by high-performance liquid chromatography with diode-array detector （HPLC-DAD） on Eclipse XDB-C18 column. Histamine, the most important amine from food safety point of view, was not found in any of the analyzed samples. Serotonin and spermidine were also not detected in any samples, while spermin was determined in all analyzed samples. At the end of drying, phenylethylamine was the predominant amine in A1 sausage group （51.6 mg/kg）, and tryptamine in B1 （38.1 mg/kg） and B3 （28.7 mg/kg） sausage groups. At the end of ripening, tryptamine was the predominant biogenic amine in all sausage groups （133, 121 and 39.8 mg/kg in A1, B1 and B3 groups, respectively）. Total level of biogenic amines in all investigated sausages did not exceed 174 mg/kg at the end of drying and 238 mg/kg at the end of ripening period. Tryptamine and cadaverine may be used as indicators of total biogenic amines for sausages produced in traditional and indusrial conditions from hot deboned and cold meat.

Modulation by Biogenic Amines for the Hemocyte Count and Prophenoloxidase Exocytosis via Receptors in Litopenaeus vannamei

Hemocyte counts and phenoloxidase(PO)activity were examined after hemolymph being incubated in dopamine(DA),noradrenaline(NE)and serotonin(5-HT).Results showed that all the three biogenic amines(BAs)had a significant impact on total hemocyte count(THC),differential hemocyte count(DHC),and intracelluar and extracelluar phenoloxidase(PO)activity.Among these Bas,DA had the strongest effect on the above parameters,whereas 5-HT had the least effect.Preincubation with D1 receptor antagonist SCH23390,D2 receptor antagonist Sulpiride and 1:1 admixture of the two could significantly inhibit the effect of DA on these parameters.SCH23390 showed a stronger inhibitory effect than Sulpiride,and the admixture exhibited the strongest effect.These results suggested that the change of hemocyte count and activation of prophenoloxidase(proPO)system in Litopenaeusvan-namei hemocyte can be regulated by BAs,and DA modulates the two parameters via its receptors.

Systematic analysis of key fermentation parameters influencing biogenic amines production in spontaneous fermentation of soy sauce

Biogenic amines(BAs),a class of toxic nitrogen-containing compounds,are commonly found in high-protein fermented foods.This study investigated whether,what and how the fermentation parameters influence the BAs accumulation in spontaneous soy sauce fermentation.The results showed that BAs accumulation in soy sauce fermentation throughout the year showed significant seasonal differences,which were closely related to temperature and pH value.Furthermore,different microbial communities were found in high-and low-BAs groups,indicating that seasonal fermentation factors affect BAs accumulation by influencing the microbial population.Following bioinformatic analysis,single-microorganism culture analysis,and simulated fermentation,it was found that lower temperature or higher NaCl concentration can reduce BAs accumulation,most likely by suppressing the proliferation of BAs-producing bacteria.This is a comprehensive study of the impact of fermentation parameters on BAs production,and will serve as a foundation for future research on BAs management.

Evolution of free amino acids, biogenic amines and volatile compounds in fermented sausages inoculated with Lactiplantibacillus plantarum and Staphylococcus simulans

Lactic acid bacteria and coagulase-negative staphylococci play an important role in the production of fermented sausages,such as inhibiting the growth of undesirable bacteria and antioxidant.In this study,the effects of inoculation with different starter cultures(Lactiplantibacillus plantarum HN108 and Staphylococcus simulans NJ209)on the free amino acids(FAAs),biogenic amines(BAs)and volatile compounds of fermented sausages were investigated using an amino acid analyzer,ultra performance liquid chromatography and gas chromatography-ion mobility spectrometry,respectively.The pH and carbonyl content of the inoculated group was significantly lower than those in the control group(P<0.05).L.plantarum HN108 significantly reduced the content of FAAs and BAs in fermented sausage production(P<0.05),while S.simulans NJ209 promoted the formation of FAAs(especially bitter amino acids)and exhibited slight BAs-reducing activity.In addition,L.plantarum HN108 promoted the formation of volatile compounds such as ketones,alcohols and alkenes in sausages.In conclusion,L.plantarum HN108 could contribute to reducing the content of putrescine and tyramine and forming the desirable flavor compounds in fermented sausages.Thus,L.plantarum HN108 is expected to be a starter culture that can improve the safety and flavor of fermented sausages.

Fluorescent probes for the detection of biogenic amines,nitrite and sulfite in food:Progress,challenges and perspective

Foodborne contaminants such as biogenic amines(BAs),nitrite and sulfite are harmful to human health.To safeguard food safety,the content of BAs,nitrite and sulfite should be strictly controlled.Small-molecule fluorescent probes are a promising analytical tool for monitoring BAs,nitrite and sulfite because they are highly sensitive and selective,offer simplicity of operation,and can enable optical signal visualization of the analyte.In this review,we summarize the most recent progress on the development of fluorescent probes for selectively detecting BAs,nitrite,and sulfite.In particular,we discuss the working mechanisms,sensing performance,and practical applications of various fluorescent probes that have been developed in recent years for detecting BAs,nitrite,and sulfite,with a particular emphasis on the utilization of these probes in food.Lastly,we discuss the research directions,trends,and prospects of molecular fluorescent probes in food applications in the future.We hope this review can offer conceptual and design guidance for researchers and practitioners to develop novel fluorescent probes for food safety.

Recent advances in fluorescent and colorimetric sensing for volatile organic amines and biogenic amines in food

Volatile organic amines and biogenic amines produced by the amino acid degradation can undeniably affect the food quality and safety,and thus causes serious health problems.It is of great urgency to exploit reliable and sensitive detection methods for amines to ensure food safety and public health.The fluorescent and colorimetric sensors offer simple and robust means to monitor amines with high sensitivity and selectivity,quick response,facile operation and low cost.Herein,we briefly review the past five years’progress in fluorescent and colorimetric sensing for monitoring organic and biogenic amines in food.The architectures of sensing materials ranging from small molecules to frameworks to polymers or self-assembly materials have been highlighted.Moreover,the main challenges and perspective of various sensing materials are presented to inspire further research and development.In the end,the development trend of new sensing materials and devices for real-time monitoring of food quality is also forecasted.This review is expected spur more research interest in design of novel amine sensing materials for future application transformation research.

Biogenic amines detection in meat and meat products:the mechanisms,applications,and future trends

Biogenic amine is one of the main categories of hazardous compounds in meat and meat products,making its detection methods vital for the assurance of edible safety.In this sense,many biogenic amine detection techniques such as chromatographic,electrophoretic,and electrochemical methods have been developed,which play an irreplaceable role in ensuring the safety of meat and meat products.Due to the increasing demand for fast and on-site detection techniques,visual detection methods have been gradually developed compared with non-visual methods such as chromatography and electrophoresis.Herein,we comprehensively review the mechanism and the latest progress of these biogenic amine detection methods;besides,we put forward the prospects for the future development of biogenic amine detection techniques,with a view to providing support for the establishment of more accurate and efficient detection,prevention and control strategies of biogenic amines.

Effect of quercetin-containing preservatives and modified atmospheric packaging on the production of biogenic amines in Pacific white shrimp(Litopenaeus vannamei)

To investigate the productions of biogenic amines(BAs)in Pacific white shrimp treated by compound preservatives(P,0.05 g/L quercetin,0.025 g/L 4-hexylresorcinol,and 0.025 g/L cinnamic acid)in combination with modified atmosphere packaging(M,80% CO_(2)/10% O_(2)/10% N_(2)),four groups of samples treated with or without preservatives and alone or in combination with modified atmosphere packaging(A,A+P,M,M+P)during storage at 4℃for 12 days were analyzed.Most BAs increased in all samples,especially,putrescine and cadaverine.MAP inhibited the increase of most BAs(except for tyramine)and psychrotrophic bacterial counts.The inhibitory effect of the compound preservatives on bacterial growth and BAs was limited in aerobically-and MAP-stored samples,but they retarded the production of tyramine,which accumulated more rapidly in MAP.Lowest total BAs and bacterial counts were found in sample M+P(78.3 mg/kg and 5.82 log cfu/g,day 12),indicating that the combined treatment of the preservatives and MAP could reduce the risk of disorders caused by BAs.

Food‑grade expression of multicopper oxidase with improved capability in degrading biogenic amines

Biogenic amines(BAs)are potential amine hazards that are detected in fermented foods and alcoholic beverages.Excessive intake of BAs may lead to allergic symptoms such as difculty in breathing,nausea,and vomiting.Degradation of BAs by multicopper oxidase(MCO)is a promising method as it has little efect on the fermentation process,food nutrition,and favor.However,the application of MCO in food industry was restricted due to its poor catalytic properties and low productivity.In this work,food-grade expression of the Bacillus amyloliquefaciens MCO(MCOB)and its three mutants were successfully constructed in Lactococcus lactis NZ3900.The expression level of MCOB in L.lactis NZ3900 was dramatically enhanced by optimizing the cultivation conditions,and the highest expression level reached 4488.1 U/L.This was the highest expression level of food-graded MCO reported so far,to our knowledge.Interestingly,the optimal reaction pH of MCOB expressed in L.lactis NZ3900 switched to 4.5,it would be more suitable for degrading BAs in food as the pH value of most fermented foods was found to be 4.5.Moreover,MCOB expressed in L.lactis NZ3900 was quite stable(with more than 80%residual activity)in the pH range of 4.0–5.5,the catalytic rate constant(kcat)and specifc activity of MCOBLS were all dramatically increased compared with that of MCOB expressed in Escherichia coli.Using histamine as the substrate,the degradation of BAs within 24 h by MCOB expressed in L.lactis NZ3900 was 69.7%higher than that expressed in E.coli.The results demonstrated the potential applications of MCOB in food industry for reduction of biogenic amines.

The Reaction of Tanshinones with Amines

The reaction of cryptotanshinone and tanshinone IIA with several biogenic amine metabolites involved in the pathogenic pathways of HE were investigated and eight 1,2,3,4- tetrahydrophenanthrene derivatives, 2-6 and 8-10, were obtained. The probable mechanism on reaction was discussed.

Effect of Salinity on the Biosynthesis of Amines in Litopenaeus vannamei and the Expression of Gill Related Ion Transporter Genes

This study examined the effect of salinity on the expression of Na+/K+-ATPase(NKA) α-subunit and vacuolar-type H+-ATPase(V-ATPase) β-subunit gene in the gill of Litopenaeus vannamei. Semi-quantitative reverse transcription-polymerase chain reaction(RT-PCR) assay showed that the expression of NKA α-subunit and V-ATPase β-subunit gene was significantly influenced by salinity. It was found that the NKA activity significantly varied with salinity in time and dose dependent manner; whereas the V-ATPase activity did not. The abundance of NKA α-subunit gene transcript increased rapidly when the salinity decreased from 26 b to 21, and slowly when the salinity decreased from 26 to 31 within the first 24 h. When the salinity decreased from 26 to 21, the transcription of NKA α-subunit gene in gill epithelium was higher at 12 h than that at 0 h, which was consistent with the result of immunoblotting assay of NKA α-subunit. In addition, salinity had a significant time- and dose-dependent effect on the concentration of biogenic amines in both hemolymph and gill. As compared to other parameters, the concentration of dopamine(DA) and 5-hydroxytryptamine(5-HT) varied in different patterns when the salinity decreased from 26 to 21 or increased from 26 to 31, suggesting that DA and 5-HT played different regulatory roles in osmotic adaption and modulation of shrimp when salinity varies.

Effect of a compound starter cultures inoculation on bacterial profile and biogenic amine accumulation in Chinese Sichuan sausages

Effects of a starter culture composed of Lactobacillus sakei,Pediococcus pentosaceus,Staphylococcus xylosus and S.carnosus at the ratios(m/m)of 1:1:1:1 on bacterial profile and biogenic amine accumulation in Chinese Sichuan sausages were demonstrated.In starter culture-inoculated sausages,Lactobacillus spp.,Pediococcus spp.and Staphylococcus spp.were predominant bacterial genus and their relative abundances ranged from 70.14%to 25.98%,57.66%to 14.08%,and 15.71%to 13.40%during fermentation,respectively.Accordingly,Lactobacillus spp.and Weissella spp.were predominant bacterial genus and their relative abundances ranged from 63.14%to 24.70%and 49.40%to 11.96%during spontaneous fermentation,respectively.Furthermore,the abundances of undesirable microorganisms such as Yersinia spp.,Enterobacter spp.,Acietobacter spp.and Psychrobacter spp.were lower than that of the control.The levels of histamine,putrescine,tyramine and cadaverine in Chinese Sichuan sausages with starter cultures inoculation were significantly lower(P<0.05)than that of the control,and were decreased by 83.09%,69.38%,51.87%and 57.20%,respectively,at the end of the ripening.These results revealed that the starter cultures inoculation was a better alternative for microbial quality improvement and biogenic amine reduction of Chinese Sichuan sausages with good sensory attributes.

Dynamics and diversity of microbial community in salmon slices during refrigerated storage and identification of biogenic amine-producing bacteria

The changes in microbial composition of salmon slices during storage at 4◦C were measured using high-throughput sequencing(HTS),and biogenic amine(BA)-producing bacteria were isolated from salmon slices to evaluate their ability to produce BAs.Fresh salmon slices had the highest bacterial diversity,which decreased with the extension of the refrigerated storage time.Phenylobacterium was the dominating genus in fresh salmon slices,followed by Photobacterium and Burkholderia,while Brochothrix became the dominant bacterium in the later stages of the storage period.Seven strains of BA-producing bacteria were isolated and determined,which varied greatly in BA production.Among these,Brochothrix thermosphacta(B5)exhibited the strongest BA-producing ability,producing 98.32 mg/mL of putrescine and 78.81 mg/mL of cadaverine,and Photobacterium phosphoreum showed a stronger histamine-producing ability(77.07 mg/mL).This study explored the microbial composition in salmon slices and offer insight into the relationship between microorganisms and BAs in salmon slices.This study provides a theoretical basis for developing antibacterial agents,decreasing the amount BAs,and extending the shelf-life of salmon slices.

Risk assessment of chemical substances of safety concern generated in processed meats

This manuscript is reviewing the presence of substances of safety concern that may be generated in different types of meat products.Such substances include N-nitrosamines that can be generated under certain conditions when using nitrite as preservative,the polycyclic aromatic hydrocarbons generated as a consequence of particular smoking processes,heterocyclic aromatic amines generated under particular cooking conditions,compounds released from the oxidation of lipids and proteins,Maillard reaction products like acrylamide and carboxymethyl lysine,and amines that can be generated and accumulated in fermented meats.These hazardous compounds,their mechanisms of generation,risks for health and ways of preventing its presence in meat products are briefly described in this review.

Celastrus paniculatus oil ameliorates synaptic plasticity in a rat model of attention deficit hyperactivity disorder

Objective:To explore the effect and mechanism of action of Celastrus paniculatus oil on the treatment of perinatal rats with attention deficit hyperactivity disorder.Methods:In the perinatal stage,the rats were either isolated or administered with lead acetate to establish an animal model of attention deficit hyperactivity disorder.Atomoxetine served as the reference standard.Animals’behaviours were assessed through Y-maze,novel object preference,fear conditioning and residentintruder aggression tests.Oxidative stress parameters,bioamine concentration(dopamine,noradrenaline and 5-hydroxytryptamine),nerve growth factor,interleukin-6,nuclear factor-κB,and tumour necrosis factor(TNF)-αwere estimated.Synaptophysin immunohistochemical assay was performed.Results:Celastrus paniculatus oil significantly improved behavioural parameters in Y maze,novel object preference,discrimination index,fear conditioning and resident intruder aggressive tests.The treatment groups showed a decrease in malondialdehyde level.Changes in the levels of dopamine,noradrenaline,and serotonin were restored by Celastrus paniculatus oil.Celastrus paniculatus oil increased nerve growth factor and decreased interleukin-6,nuclear factor-κB,and TNF-α.Synaptophysin immunoreactivity was also improved by Celastrus paniculatus oil with alleviated reactive gliosis,degeneration,and vascular proliferation.Conclusions:This research shows the therapeutic potential of Celastrus paniculatus oil for the treatment of attention deficit hyperactivity disorder.