International journal of food microbiology最新文献

{"title":"The impact of fermentation length and dough composition on the stability of liquid sourdough starters","authors":"Charlotte Bauer Munch-Andersen,&nbsp;Davide Porcellato,&nbsp;Tove Gulbrandsen Devold,&nbsp;Hilde Marit Østlie","doi":"10.1016/j.ijfoodmicro.2024.110932","DOIUrl":"10.1016/j.ijfoodmicro.2024.110932","url":null,"abstract":"<div><div>Sourdough breadmaking on an industrial scale requires robust, well-performing starters that bring attractive characteristics to the product. The active nature of liquid starters provides a faster fermentation process compared to their dehydrated counterparts. However, liquid sourdough starters require meticulous management in order to maintain stability and functionality during cold storage at 4 °C.</div><div>This study investigated the stability of three liquid sourdough starters during storage and also the impact of prolonged fermentation, the addition of diastatic malted wheat flour, and a neutralising agent (CaCO₃).</div><div>The sourdough starters were evaluated for their microbial viability and metabolic activity at three individual time points during 16 weeks of cold storage. The microbial composition was analysed using culture-dependent and culture-independent methods, and metabolic changes were investigated using chromatographic methods.</div><div>Two types of sourdough starter showed satisfying viability of lactic acid bacteria (&gt; 7 log CFU/g) and metabolic stability throughout 16 weeks of cold storage. The introduction of malted wheat flour and CaCO₃ caused a decline in viability to &lt;7 log CFU/g within 8 weeks in the third sourdough starter type and additionally revealed an ongoing metabolic activity of this sourdough starter during cold storage.</div><div>Prolonged fermentation influenced the free amino acid profile, whereas adjusting the sourdough starter formula resulted in a different fungal microbiota and increased levels of fermentable substrates (maltose), organic acids (lactic acid), and aromatic compounds (alcohol and aldehydes).</div><div>These findings provide stakeholders and researchers in sourdough fermentation technology with new insights concerning the stability of cold-stored liquid sourdough starters.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110932"},"PeriodicalIF":5.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role and the determination of the LuxI protein binding targets in the formation of biogenic amines in Hafnia alvei H4","authors":"Xue Li ,&nbsp;Yanan Wang ,&nbsp;Gongliang Zhang ,&nbsp;Jingran Bi ,&nbsp;Hongshun Hao ,&nbsp;Hongman Hou","doi":"10.1016/j.ijfoodmicro.2024.110928","DOIUrl":"10.1016/j.ijfoodmicro.2024.110928","url":null,"abstract":"<div><div><em>Hafnia alvei</em> is a spoilage microorganism that possesses the LuxI/LuxR-type quorum sensing (QS) system. Biogenic amines (BAs) are important in food spoilage and safety, yet the role of QS in BA formation remains poorly understood. This study investigated the ability of <em>H. alvei</em> H4 to produce BAs in fish flesh and decarboxylase culture media. The findings showed that <em>H. alvei</em> H4 produced substantial amounts of putrescine and cadaverine in turbot flesh, with its enhanced amine-producing capacity potentially leading to the eventual deterioration of the fish. Furthermore, the deletion of the QS element—AHL synthase gene <em>luxI</em>—affected the concentrations of both BAs. Based on these observations, the present study conducted multifaceted experiments, including phenotypic assessments and analyses of gene expression, to explore the role of <em>luxI</em> and to identify its specific binding targets. The results indicated that putrescine formation in <em>H. alvei</em> H4 primarily occurred via the arginine deiminase (ADI) pathway, with <em>luxI</em> playing a positive role in the conversion of arginine to ornithine and subsequently to putrescine. The reduction in putrescine content observed in a <em>luxI</em> mutant (Δ<em>luxI</em>) was attributed to the direct binding of the LuxI protein to the promoters of the <em>argF</em> and <em>speC</em> genes, which code for ornithine carbamoyltransferase and ornithine decarboxylase, respectively. The findings of this study provided the basis to understand the influence of QS on BA production in <em>H. alvei</em>, by specifically demonstrating the involvement of the <em>luxI</em> gene on putrescine and cadaverine production<em>.</em></div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110928"},"PeriodicalIF":5.0,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142406366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disruption of the signal recognition particle pathway leading to impaired growth, sugar metabolism and acid resistance of Lactococcus lactis","authors":"Meng Wang,&nbsp;Yanying Yue,&nbsp;Xiaoce Zhu,&nbsp;Mengjie Wang,&nbsp;Yifei Zhang,&nbsp;Jian Kong,&nbsp;Tingting Guo","doi":"10.1016/j.ijfoodmicro.2024.110929","DOIUrl":"10.1016/j.ijfoodmicro.2024.110929","url":null,"abstract":"<div><div><em>Lactococcus lactis</em> is a well-known workhorse for dairy products, whose important industrial traits are tightly associated with numerous cytoplasmic membrane proteins. However, roles of the signal recognition particle (SRP) pathway responsible for membrane protein targeting have not been studied in <em>L. lactis</em>. In this work, the putative genes <em>ffh</em> and <em>ftsY</em> encoding SRP pathway components were identified in the genome of <em>L. lactis</em> NZ9000. Experimental evidence showed that sequence mutation in either the <em>ffh</em> or <em>ftsY</em> was not lethal, but prolonged the lag phase of the resultant mutants Δffh and ΔftsY by 2 h and lowered their biomass to 85.7 % of the wild type under static conditions, as well as deprived the mutants of improved growth capacity under aerobic respiration conditions. Besides, the speeds of glucose consumption and lactate production were significantly decreased in the mutants. Then, the impact of the SPR components on acid resistance was detected, showing that the <em>ffh</em> and <em>ftsY</em> were transcriptionally upregulated by 3.02 ± 1.21 and 8.66 ± 1.01-fold in the wild type during acid challenge at pH 3.0, and cell survival of the Δffh and ΔftsY decreased by10- and 100-fold compared with the wild type. To explore the possible mechanism about the SRP pathway involved in the above physiological traits, proteomics analysis was performed and revealed that disruption of the Ffh or FtsY led to decrease in ribosomal proteins, but increase in DnaK, GroEL and heat shock protein GrpE, indicating that the SRP pathway was closely linked to protein synthesis and folding in <em>L. lactis</em>. Decrease in the fructose-bisphosphate aldolase, respiratory complexes NADH dehydrogenase, as well as glutamate decarboxylase was also detected in the Δffh and ΔftsY, which is consistent with the phenomena of impaired sugar metabolism and acid resistance. Our results demonstrated the dispensable SRP pathway could contribute to the maintenance of metabolism homeostasis and acid resistance of <em>L. lactis</em>.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110929"},"PeriodicalIF":5.0,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142390332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The applicability of the SERS technique in food contamination testing – The detailed spectroscopic, chemometric, genetic, and comparative analysis of food-borne Cronobacter spp. strains","authors":"K. Niciński ,&nbsp;E. Witkowska ,&nbsp;D. Korsak ,&nbsp;M. Szuplewska ,&nbsp;A. Kamińska","doi":"10.1016/j.ijfoodmicro.2024.110930","DOIUrl":"10.1016/j.ijfoodmicro.2024.110930","url":null,"abstract":"<div><div>Microorganisms assigned as <em>Cronobacter</em> are Gram-negative, facultatively anaerobic, bacteria widely distributed in nature, home environments, and hospitals. They can also be detected in foods, milk powder, and powdered infant formula (PIF). Additionally, as an opportunistic pathogen, <em>Cronobacter</em> may cause serious infections, sometimes leading to the death of neonates and infants. Thus, it is essential to test food products for the presence of <em>Cronobacter</em> spp. The currently used standard described in ISO 22964:2017 is a laborious method that could be easily replaced by surface-enhanced Raman scattering (SERS).</div><div>Here, we demonstrate that SERS allows the identification of food-borne bacteria belonging to <em>Cronobacter</em> spp. based on their SERS spectra. For this purpose, twenty-six <em>Cronobacter</em> strains from different food samples were analyzed. Additionally, it was shown that it is possible to differentiate them from other closely related pathogens such as <em>Salmonella enterica</em> subsp. <em>enterica</em>, <em>Escherichia coli</em>, or <em>Enterobacter</em> spp. The SERS results were supported by principal component analysis (PCA), as well as and sequencing of 16S rRNA<em>, rpoB</em> and <em>fusA</em> genes. Last but not least, it was demonstrated that the cells of <em>Cronobacter sakazakii</em> may be easily separated from PIF using an appropriate filter, microfluidic chip, and dielectrophoresis (DEP) technique.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110930"},"PeriodicalIF":5.0,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142406365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-pressure processing and heat treatment of Murrah buffalo milk: Comparative study on microbial changes during refrigerated storage","authors":"Darren Sim Xuan Yu ,&nbsp;Chong Kah Hui ,&nbsp;Mohammad Rashedi Ismail-Fitry ,&nbsp;Pankaj Koirala ,&nbsp;Nilesh Nirmal ,&nbsp;Mahmud Ab Rashid Nor-Khaizura","doi":"10.1016/j.ijfoodmicro.2024.110926","DOIUrl":"10.1016/j.ijfoodmicro.2024.110926","url":null,"abstract":"<div><div>This study aims to evaluate the effect of high-pressure processing (HPP) (500 and 600 MPa for 3 min and 5 min) on the microbial changes of Murrah buffalo milk in comparison to heat treatment (72 °C for 15 s of holding time) during refrigerated storage of 28 days. The results indicated that the total plate count (TPC) of raw milk at day 0 was 5.5 ± 0.6 log₁₀ CFU/mL. At day 0, heat treatment lowered TPC to 3.9 ± 0.6, while HPP treatment was in the range of 4.1 ± 0.3 to 4.8 ± 0.6 log₁₀ CFU/mL. Similarly, lowered yeast and mold count and lactic acid bacteria were noted in heat- and HPP-treated milk samples compared to the control sample during refrigerated storage. There were no <em>Staphylococcus aureus</em> and <em>Escherichia coli</em> detected in heat and HPP-treated samples. Heat or HPP treatment at 600 MPa for 5 min significantly extended the shelf-life of Murrah buffalo milk for three weeks at the refrigerated storage. In addition, HPP treatment did not alter the pH, lightness (<em>L</em>* value), protein, or fat content of Murrah buffalo milk during refrigerated storage. Hence HPP at 600 MPa for 5 min could be a suitable alternative to conventional heat treatment.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110926"},"PeriodicalIF":5.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142377917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic and phenotypic polymorphism of Clostridium botulinum Group II strain Beluga through laboratory domestication","authors":"Katja Selby,&nbsp;François P. Douillard,&nbsp;Miia Lindström","doi":"10.1016/j.ijfoodmicro.2024.110927","DOIUrl":"10.1016/j.ijfoodmicro.2024.110927","url":null,"abstract":"<div><div>Laboratory domestication is the result of genetic and physiological changes of organisms acquired during numerous passages <em>in vitro</em>. This phenomenon has been observed in bacteria as well as in higher organisms. In an effort to understand the impact of laboratory domestication on the foodborne pathogen <em>Clostridium botulinum</em> and related microbial food safety research, we investigated multiple spore stocks of <em>C. botulinum</em> Group II Beluga from our collection, as that is a widely applied model strain used in laboratories over decades. An acquired nutrient auxotrophy was confirmed as thymidine dependency using phenotypic microarrays. In parallel, whole-genome re-sequencing of all stocks revealed a mutation in <em>thyA</em> encoding thymidylate synthase essential for <em>de-novo</em> synthesis of dTMP from dUMP in the auxotrophic stocks. A <em>thyA</em>-deficient Beluga variant stock was successfully complemented by introducing an intact variant of <em>thyA</em> and thymidine prototrophy was restored, indicating that the thymidine auxotrophy was solely due to the presence of a SNP in <em>thyA</em>. Our data suggested that this mutation, deleterious under nutrient-poor growth conditions in a chemically defined medium, has been present and maintained in laboratory stocks for nearly 30 years. Yet, the mutation remained unidentified since receiving the strain, most likely due to routine use of culture conditions optimized for growth performance. This work pinpoints the need for careful monitoring of model strains extensively used in laboratory settings at both phenotypic and genomic level. In applications like food safety challenge tests, compromised strains could cause incorrect predictions and thereby have deleterious consequences. To mitigate the risk of acquiring mutations, we recommend keeping passage numbers of laboratory strains low and to avoid single-colony passaging. In addition, relevant strains should be subjected to regular WGS checks and physiological validation to exclude DNA mutations with potential negative impacts on research data integrity and reproducibility.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110927"},"PeriodicalIF":5.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142390425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antibiofilm mechanism of 2R,3R-dihydromyricetin by targeting sortase A and its application against Staphylococcus aureus adhesion on eggshell","authors":"Wenyi Ran ,&nbsp;Peirui Yi ,&nbsp;Ling Jiang,&nbsp;Yang Yu,&nbsp;Kai Zhong,&nbsp;Yanping Wu,&nbsp;Hong Gao","doi":"10.1016/j.ijfoodmicro.2024.110925","DOIUrl":"10.1016/j.ijfoodmicro.2024.110925","url":null,"abstract":"<div><div>Biofilm formation of <em>Staphylococcus aureus</em> in food processing environments raises significant safety concerns, necessitating the development of new antibiofilm approaches for controlling <em>S. aureus</em> contamination. This study aimed to elucidate the antibiofilm mechanism of <em>2R</em>,<em>3R</em>-dihydromyricetin (DMY), a natural flavonoid, against <em>S. aureus</em> and evaluate its efficacy in reducing bacterial adhesion to eggshell. The results revealed that DMY was a potent inhibitor of <em>S. aureus</em> sortase A (SrtA) with an IC₅₀ of 73.43 μM, preventing bacterial adhesion to fibrinogen and subsequent biofilm formation. Fluorescence quenching assay and surface plasmon resonance analysis confirmed that DMY could directly bind to <em>S. aureus</em> SrtA. Notably, circular dichroism spectra demonstrated a conformational change in SrtA from α-helical to β-sheet structure upon DMY binding. Molecular dynamics simulation suggested that DMY bound to the catalytic pocket of <em>S. aureus</em> SrtA via hydrophobic interactions and hydrogen bonds. Furthermore, fluorescence microscopic observations further revealed that DMY attenuated the biofilm-related phenotype of SrtA by decreasing the anchoring of <em>S. aureus</em> protein A (SpA) onto cell wall. Importantly, pretreatment with 125 μg/mL DMY significantly reduced 1.14–1.75 log CFU/cm² of <em>S. aureus</em> adhered on eggshells. Overall, these findings highlight how specific targeting of SrtA by DMY inhibits the attachment stages of biofilm development in <em>S. aureus</em>, making it a promising candidate for a novel disinfectant against this pathogen in the food industry.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110925"},"PeriodicalIF":5.0,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142375432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of a novel lytic phage to control enterotoxigenic Escherichia coli in dairy food matrices","authors":"Madhvi Chahar ,&nbsp;Anuj Rana ,&nbsp;Vinay Kumar Gupta ,&nbsp;Anu Singh ,&nbsp;Namita Singh","doi":"10.1016/j.ijfoodmicro.2024.110924","DOIUrl":"10.1016/j.ijfoodmicro.2024.110924","url":null,"abstract":"<div><div>A novel <em>Escherichia coli</em> phage designated as EC BD was isolated from cattle dung samples. Transmission electron microscopy demonstrated that the morphology of phage EC BD belongs to the family Myoviridae. The efficiency of plating (EOP) and scanning electron microscopy revealed the strong lytic activity of phage EC BD with a large burst size and a short latent period. Whole genome data analysis suggested that phage EC BD was inclined towards being completely lytic and revealed the absence of toxins, virulence and antibiotic resistance genes. Phylogenomic analysis of phage EC BD receptor binding proteins (RBPs) showed 74–100 % similarity with sixteen Enterobacter phages, representing their broad host range. The phage genome contains 262 ORFs, of which 107 displayed a unique pattern and additionally, the presence of a tRNA gene directed their fast replication and high stability. Comparative genome analysis suggested phage EC BD as a novel member of the genus <em>Duplodnaviria</em> and family Myoviridae. The efficiency of phage EC BD was determined in dairy food matrices (milk, cheese and paneer) artificially contaminated with enterotoxigenic <em>E. coli</em> strains ETEC H10407, ETEC K 12S and ETEC PB 176 with a significant reduction of 4.8, 6.0 and 5.3 log CFU/mL in milk and a substantial 4.9, 5.8 and 4.6 log CFU/mL reduction in cheese samples after 6 days at low storage temperature (4 °C); furthermore, within the similar conditions, paneer samples showed 4, 5.1 and 3.5 log CFU/mL reduction. EC BD phage treatment represents the complete eradication of three ETEC strains in liquid and semisolid dairy food matrices. This study suggested that phage EC BD might have potential as a biocontrol approach against ETEC foodborne infections.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110924"},"PeriodicalIF":5.0,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142346239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Catalogue of surface proteins of Lactiplantibacillus plantarum strains of dairy and vegetable niches","authors":"Maria Fiorella Mazzeo ,&nbsp;Alida Sorrentino ,&nbsp;Stefano Morandi ,&nbsp;Houssam Abouloifa ,&nbsp;Abdeslam Asehraou ,&nbsp;Milena Brasca ,&nbsp;Rosa Anna Siciliano","doi":"10.1016/j.ijfoodmicro.2024.110922","DOIUrl":"10.1016/j.ijfoodmicro.2024.110922","url":null,"abstract":"<div><div><em>Lactiplantibacillus plantarum</em> (formerly <em>Lactobacillus plantarum</em>) exhibits relevant probiotic and technological features and is widely used in food industries, improving flavour, texture and organoleptic properties of fermented products. Cell-surface proteins have a key role in the molecular mechanisms responsible for healthy effects, being the first actors in the bacteria - host interactions. Proteins present on the surface of four <em>L. plantarum</em> strains (two isolated from vegetable matrices and two from dairy products) were identified by proteomics with the aim to gain a comprehensive picture of differences in protein profiles potentially related to the habitat of origin and specific properties of the analyzed strains. Results highlighted a more diversified pattern of surface proteins in strains from vegetable matrices compared to those from dairy matrices (&gt;500 proteins <em>vs</em> about 200 proteins, respectively). The four strains shared a core of 143 proteins, while 445 were specifically present in strains from vegetable matrices and 26 were peculiar of strains from dairy origin. Sortase A, involved in adhesion, and choloylglycine hydrolase (bile salt hydrolase) were detected only in strains from vegetable matrices. The peculiar molecular functions of identified proteins suggested that these strains, and in particular <em>L. plantarum</em> S61, could have a significant probiotic and biotechnological potential.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110922"},"PeriodicalIF":5.0,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142346240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel high-level phenyllactic acid fungal producer, Kodamaea ohmeri w5 screened from fermented broad bean-chili-paste","authors":"Chi Zhao ,&nbsp;Petri Penttinen ,&nbsp;Lingzi Zhang ,&nbsp;Ling Dong ,&nbsp;Fengju Zhang ,&nbsp;Decong Liao ,&nbsp;Suyi Zhang ,&nbsp;Zhihua Li ,&nbsp;Xiaoping Zhang","doi":"10.1016/j.ijfoodmicro.2024.110923","DOIUrl":"10.1016/j.ijfoodmicro.2024.110923","url":null,"abstract":"<div><div>Phenyllactic acid (PLA) is a broad-spectrum and efficient antimicrobial phenolic acid with potential applications in the food industry. Previous studies have demonstrated that fungi may be ideal producers of PLA. In this study, 15 fungi screened from Doubanjiang with the ability to produce PLA were first reported, including <em>Wickerhamomyces anomalus</em>, <em>Candida etchellsii</em>, <em>Candida parasitosis</em>, <em>Pichia kudriavzevii</em>, <em>Pichia membranifaciens</em> and <em>Kodamaea ohmeri</em>. Among them, <em>K. ohmeri</em> w5 had the highest PLA yield, producing up to 7160 mg/L PLA in shake flask fermentation with phenylalanine as substrate, which was more than ten times higher than the PLA produced by wild-type LAB under the similar conditions. In addition, <em>K. ohmeri</em> w5 was able to grow under extreme hypertonic conditions of 20 % NaCl (<em>w</em>/<em>v</em>) and 50 % glucose (w/v) as well as produce 57.12 ± 0.42 and 1609.22 ± 36.26 mg/L of PLA, respectively. Furthermore, the fermentation supernatant of <em>K. ohmeri</em> w5 demonstrated direct inhibitory effects against foodborne pathogenic microorganisms, <em>Aspergillus flavus</em> and <em>Bacillus cereus</em>. However, the inhibitory effect was weaker than that of the PLA standard at the same concentration. Further, 12,497,932 bp of w5 genome-wide information was obtained by sequencing and assembling. And its gene model was predicted based on transcriptomic evidence, which showed that a total of 7 genes related to PLA synthesis were identified in the w5 genome. Based on qRT-PCR, structure prediction, and molecular docking, a potentially key genetic resource from <em>K. ohmeri</em> w5 for PLA production was uncovered. The results will provide novel producers of PLA and its potential genetic resources.</div></div>","PeriodicalId":14095,"journal":{"name":"International journal of food microbiology","volume":"426 ","pages":"Article 110923"},"PeriodicalIF":5.0,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}