Cocktail Of Bacteria Research Articles

Enhancing food safety: Employing ultraviolet-C light emitting diodes for water, leaf, and surface disinfection

This study aimed to explore the use of ultraviolet-C light emitting diodes that emit light at 255 nm and 265 nm, to disinfect bacteria present at occurrence levels and spiked in water matrices, salads and stainless-steel surfaces. The UV-C LEDs effectively inactivated bacteria associated with food outbreaks (Salmonella enterica, Listeria monocytogenes and Escherichia coli) as well as a cocktail of bacteria isolated from packaged salads. Combining the wavelengths did not enhance disinfection. Even low UV fluences of 4 mJ/cm2 achieved a significant 6-log reduction of bacteria spiked in water at high initial concentrations of approximately 108 CFU/mL. Exposure of salad (lettuce and arugula) leaves (110 mJ/cm2) and contaminated stainless-steel surfaces (11 mJ/cm2) to three small LEDs that emitted light at 265 nm reduced the pathogenic bacteria by 3 and 2-logs, respectively. The results obtained show that this disinfection technology could be promising for the food industry to guarantee effective inactivation of bacteria associated with foodborne diseases present in water, food and surfaces. Industrial relevanceThis study demonstrated the potential of ultraviolet-C light emitting diodes, emitting at 255 nm and 265 nm, to provide an effective and sustainable disinfection solution for the food industry, ensuring the inactivation of bacteria associated with foodborne diseases on water, food, and surfaces, thereby enhancing food safety. Additionally, this technology holds potential for extending product shelf-life, further benefiting the food industry. The results highlighted the effectiveness of UV-C LEDs even at low fluences, making them a practical choice for modern disinfection needs.

Evaluation of the performance of a three-strains lactic acid bacteria cocktail for the control of Listeria monocytogenes on marinated lean pork

The aim of this study was to evaluate the addition of a cocktail of three lactic acid bacteria (LAB) (Lactococcus lactis, Lacticaseibacillus paracasei and Lactiplantibacillus plantarum) as a protective culture into marinated pork. The pork was artificially inoculated with two Listeria monocytogenes strains and stored for 12 days. Two packagings were used: vacuum or modified atmosphere packaging (MAP). LAB, L. monocytogenes, psychrotrophic bacteria, pH, aw, color, the metataxonomic profile and the sensorial quality of the product were evaluated. The growth of L. monocytogenes under vacuum and MAP was reduced with the use of the LAB up to 0.8 and 0.7 log10 CFU/g, respectively. LAB counts gradually increased, which was accompanied by a slight decrease in pH. In LAB samples, psychrotrophic bacteria showed a reduction at day 12 as compared to non-inoculated samples. Some minor differences were also observed among samples for color and sensory parameters. Regardless of the type of packaging, the microbiota of the marinated pork was dominated initially by Photobacterium and subsequently during storage by a diversity of LAB. The application of LAB could help to obtain a safe product, although further evaluation would be required to optimize the application of the LAB cocktail in real-scale commercial scenarios.

Application of bacteria and bacteriophage cocktails for biological control of houseflies

BackgroundHouseflies, Musca domestica L., are an ubiquitous pest that can transmit numerous diseases and threaten human health. Increasing insecticide resistance shown by houseflies necessitates the develop new control alternatives. The housefly gut is densely colonized with microorganisms that interact with each other dynamically and benefit the host’s health. However, the impact of multiple symbiotic bacteria on the composition of housefly gut microbiota and the host’s activities remains unclear.MethodsWe isolated and cultured 12 bacterial species from the intestines of housefly larvae. We also isolated seven bacteriophages to precisely target the regulation of certain bacterial species. Using 16S rRNA high-throughput gene sequencing, we analyzed the bacterial diversity after orally administering bacteria/phage cocktails to houseflies.ResultsOur results showed that larval growth was promoted, the abundance of beneficial bacteria, such as Klebsiella and Enterobacter, was increased and the abundance of harmful bacteria, such as Providencia, Morganella and Pseudomonas, was decreased in housefly larvae fed with the beneficial bacteria cocktail. However, oral administration of both beneficial and harmful bacterial phage cocktails inhibited larval growth, probably due to the drastic alteration of gut flora. Untargeted metabolomics using liquid chromatography–mass spectrometry showed that disturbances in gut microbiota changed the larval metabolite profiles. Feeding experiments revealed that disrupting the intestinal flora suppressed the beneficial bacteria and increased the harmful bacteria, causing changes in the metabolites and inhibiting larval growth.ConclusionsBased on our results, bacteria/phage cocktails are effective tools for regulating the intestinal flora of insects and have a high potential as a biological control agent for incorporation into an integrated pest management program.Graphical abstract

Bifidobacterium longum promotes postoperative liver function recovery in patients with hepatocellular carcinoma

Timely liver function recovery (LFR) is crucial for postoperative hepatocellular carcinoma (HCC) patients. Here, we established the significance of LFR on patient long-term survival through retrospective and prospective cohorts and identified a key gut microbe, Bifidobacterium longum, depleted in patients with delayed recovery. Fecal microbiota transfer from HCC patients with delayed recovery to mice similarly impacted recovery time post hepatectomy. However, oral gavage of B.longum improved liver function and repair in these mice. In a clinical trial of HCC patients, orally administering a probiotic bacteria cocktail containing B.longum reduced the rates of delayed recovery, shortened hospital stays, and improved overall 1-year survival. These benefits, attributed to diminished liver inflammation, reduced liver fibrosis, and hepatocyte proliferation, were associated with changes in key metabolic pathways, including 5-hydroxytryptamine, secondary bile acids, and short-chain fatty acids. Our findings propose that gut microbiota modulation can enhance LFR, thereby improving postoperative outcomes for HCC patients.

Testing the Induction of Metritis in Healthy Postpartum Primiparous Cows Challenged with a Cocktail of Bacteria.

Metritis is a postpartum uterine disease with greater incidence in primiparous than in multiparous cows. In primiparous cows, the impact on production and health is lessened, presumably due to a superior immune response. Here, we tested whether an in vivo model of clinical metritis induction developed for postpartum multiparous Holstein cows would produce similar results in primiparous cows. Thirty-six cows were randomly assigned to one of three groups and received intrauterine infusion within 24 h of parturition. The controls were infused with sterile saline; the low-dose group received a bacterial cocktail containing 103 cfu of Escherichia coli, Trueperella pyogenes, and Fusobacterium necrophorum; and the high-dose group were infused with 106 cfu of the same cocktail. Production, health traits, and the vaginal discharge culture were assessed daily, from enrollment until 14 d in milk. Clinical metritis occurred in 64% of high-dose cows, 33% of the controls, and 42% of low-dose cows, with no significant difference of incidence between groups. However, when accounting by time, high-dose cows had a 2.7 times greater hazard of metritis compared with the controls. The bacterial challenge affected milk production and dry matter intake tended to decrease. In the high-dose group, a greater growth of F. necrophorum in the selective medium was also observed, suggesting an association with metritis. Therefore, this study suggests intrauterine inoculation with 106 cfu of this bacterial cocktail elicits physical and clinical outcomes consistent with clinical metritis.

The Impact of Different Inoculation Schemes on the Microbiota, Physicochemical and Sensory Characteristics of Greek Kopanisti Cheese throughout Production and Ripening.

Kopanisti is a Greek PDO cheese, which is traditionally produced by the addition of an amount of over-mature Kopanisti, called Mana Kopanisti, to initiate cheese ripening. The aim of this study was the production of four types of Kopanisti cheese (A-D) using pasteurized cow milk, and a combination of the following starters/adjuncts in order to test their ability to be used in Kopanisti cheese production: A: Lactococcus lactis subsp. lactis and Lacticaseibacillus paracasei, B: L. lactis and Lc. paracasei/Mana Kopanisti, C: L. lactis and Lc. paracasei/Ligilactobacillus acidipiscis and Loigolactobacillus rennini, D: Lig. acidipiscis and Loig. rennini. Throughout production and ripening, classical microbiological, metataxonomics and physicochemical analyses were employed, while the final products (Day 35) were subjected to sensory analysis as well. Most interestingly, beta-diversity analysis of the metataxonomics data revealed the clusters constructed among the Kopanisti types based on the different inoculation schemes. On day 35, Kopanisti A-C types clustered together due to their similar 16S microbiota, while Kopanisti D was highly differentiated. On the contrary, ITS data clustered Kopanisti B and C together, while Kopanisti A and D were grouped seperately. Finally, based on the sensory evaluation, Kopanisti C appeared to have the most suitable bacteria cocktail for the Kopanisti cheese production. Therefore, not only were the conventional starters used, but also the Lig. acidipiscis and Loig. rennini strains could be used in a standardized Kopanisti cheese production that could lead to final products of high quality and safety.

Leuconostoc mesenteroides and Pediococcus pentosaceus Non-Alcoholic Pearl Millet Beverage Enriched with Moringa oleifera Leaf Powder: Nutritional and Sensory Characteristics

Non-alcoholic cereal beverages (NACB) are usually produced through uncontrolled fermentation driven by a cocktail of bacteria resulting in final product variability. Hence, to commercialise fermented traditional cereal beverages bioburden microbial cultures are required. This investigation aimed to evaluate the physicochemical, nutritional, and sensory characteristics of NACB produced using pure cultures of Leuconostoc mesenteroides and Pediococcus pentosaceus. Pearl millet extract (PME) pasteurised at 85 °C for 15 min and cooled to 40 °C was inoculated with Leuconostoc mesenteroides and Pediococcus pentosaceus at 0.050% and 0.025% (1:0.5), respectively, and fermented at 37 °C for 18 h, referred to as plain non-alcoholic pearl millet beverage (PNAPMB). Moringa supplemented non-alcoholic pearl millet beverage (MSNAPMB) was produced following the same method as PNAPMB but a 4% moringa leaf extract powder was added before hydration of the pearl millet powder. The traditional non-alcoholic pearl millet beverage (TNAPMB) was prepared by mixing water and pearl millet flour (1:1.25; PMF:Water) and hydrated for 3 h at 25 °C. The mixture was divided into ¼ slurry which was mixed with sprouted rice flour (SRF) and ¾ portion that was gelatinised with 1 L of boiling water and cooled to 40 °C. The two portions were mixed and fermented at 37 °C for 18 h, followed by sieving, dilution with water (1:0.5, filtrate:water), and pasteurization for 15 min at 85 °C. The growth of lactic acid bacteria, pH, total titratable acidity (TTA), and sugar in PNAPMB and MSNAPMB were determined at 3 h intervals during fermentation. The final beverages were also analysed for proximate, colour and metabolites. The lactic acid bacteria were significantly (p < 0.05) affected by the fermentation period and increased from 3.32 to 7.97 log CFU/mL (pH 4.14) and 3.58 to 8.38 log CFU/mL (pH 3.65) for PNAPMB and MSNAPMB, respectively. The total titratable acidity significantly (p < 0.05) increased from 0.14 to 0.22% and from 0.17 to 0.38% in PNAPMB and MSNAPMB, respectively. The protein, total fat, moisture total sugar, and carbohydrates differed significantly (p < 0.05) among the samples. PNAPMB was preferred by a consumer panel followed by MSNAPMB and TNAPMB. Volatile compounds with beneficial anti-inflammatory and anti-pathogenic properties were identified in the beverages. Innovative fermentation of pearl millet extract using purified bioburden cultures was possible and the added Moringa oleifera leaf powder improved the nutritional quality of the resulting beverage.

Metagenomic and culturomic analysis of gut microbiota dysbiosis during Clostridium difficile infection

Recently, cocktail of bacteria were proposed in order to treat Clostridium difficile infection (CDI), but these bacteriotherapies were selected more by chance than experimentation. We propose to comprehensively explore the gut microbiota of patients with CDI compared to healthy donors in order to propose a consortium of bacteria for treating C. difficile. We compared stool samples composition from 11 CDI patients and 8 healthy donors using two techniques: metagenomics, 16S V3-V4 region amplification and sequencing and culturomics, high throughout culture using six culture conditions and MALDI-TOF identification. By culturomics, we detected 170 different species in the CDI group and 275 in the control group. Bacteroidetes were significantly underrepresented in the CDI group (p = 0.007). By metagenomics, 452 different operational taxonomic units assigned to the species level were detected in the CDI group compared to 522 in the control group. By these two techniques, we selected 37 bacteria only found in control group in more than 75% of the samples and/or with high relative abundance, 10 of which have already been tested in published bacteriotherapies against CDI, and 3 of which (Bifidobacterium adolescentis, Bifidobacterium longum and Bacteroides ovatus) have been detected by these two techniques. This controlled number of bacteria could be administrated orally in a non-invasive way in order to treat CDI.

Nitrogen source contribution in sugarcane-inoculated plants with diazotrophic bacterias under urea-N fertigation management

Although Brazilian sugarcane crops use lower nitrogen rates when compared to other producing countries, the biological nitrogen fixation (BFN) could be performed aiming to reduce costs, since almost all nitrogen fertilization used in Brazil is imported. BFN can occur in sugarcane; however, its role in non-leguminous plants is controversial. Therefore, this study aimed to assess the nitrogen source contribution (using N isotope 15N technique) along a growing period in sugarcane plants under different management (diazotrophic bacteria inoculation and N fertigation rates). The natural abundance of nitrogen isotope (15N) abundance in + 1 leaves of fourth ratoon cultivar SP 80-3280 was used to indicate the comparative importance of N sources, including BFN for sugarcane nutrition. The treatments were irrigated with two levels of nitrogen fertilizer 50 and 100 kg ha−1 (urea source), including a control without fertilizer, with (I) and without (NI) inoculation of nitrogen-fixing bacterias. The bacteria cocktail used consisted of five strains: Gluconacetobacter diazotrophicus, Herbaspirillum seropedicae, H. rubrisubalbicans, Burkholderia tropica and Azospirillum amazonense. Although the nitrogen content in + 1 leaves, the above ground dry matter, cane yield and stalk sugar content expanded by increasing nitrogen fertilizer rates, no significant interactions between nitrogen-fixing bacteria inoculation and nitrogen fertilizer rates were observed. In the treatment without N fertilizer application, no differences in δ15N‰ (per thousand) values between sugarcane-inoculated and sugarcane-non-inoculated sugarcane leaves was found. The temporal variation of δ15N‰ in sugarcane + 1 leaves indicated that nitrogen content and δ15N‰ values decreased during the phenological development stages and that the main sources of nitrogen for sugarcane were from synthetic fertilizer and mineralization of nitrogen from soil organic matter.

Umweltmikrobiom

Es gibt immer mehr Hinweise aus epidemiologischen und tierexperimentellen Studien, dass das Mikrobiom ein wichtiger Faktor fur die Entstehung von Asthma bronchiale und Allergien sein konnte. Diese Studien beruhen auf neuen DNA-basierten Sequenzierungstechniken, die einen tiefen Einblick in die mikrobielle Vielfalt in unserer Umwelt und auf bzw. in unseren Korperoberflachen erlauben. Das Umweltmikrobiom in Innenraumen wird zu einem grosen Teil aus der auseren Umwelt definiert, aber zu einem wesentlichen Teil auch durch das Mikrobiom seiner humanen und tierischen Einwohner bestimmt. Dass das Umweltmikrobiom eine wesentliche Rolle bei der Entstehung von Asthma und Allergien spielen kann, geht am deutlichsten aus den Bauernstudien hervor. Diese haben wiederholt einen erheblichen Schutz vor der Entstehung dieser Krankheiten bei den Kindern gezeigt, die eine hohe mikrobielle Exposition aufweisen. Dabei hat es den Anschein, dass es nicht einzelne Keime sind, die dies bewirken, sondern vielmehr ein mikrobieller Cocktail aus Umweltbakterien und -schimmelpilzen. Der starkste Schutz findet sich bei Kindern der Amischen, die eine sehr traditionelle Landwirtschaft betreiben. In dieser Bevolkerungsgruppe ist der Heuschnupfen eine Raritat, die allergische Sensibilisierung etwa 6‑mal seltener als bei Stadtkindern in Deutschland, und virusinduzierte obstruktive Bronchitiden ohne Progression in ein allergisches Asthma herrschen vor.

Behavior of Vibrio parahemolyticus cocktail including pathogenic and nonpathogenic strains on cooked shrimp

Pathogenic Vibrio parahaemolyticus, an important foodborne bacterium, coexists with nonpathogenic strains of V. parahaemolyticus in the environment. However, current predictive models for V. parahaemolyticus usually focused on single strain without considering the pathogenic and nonpathogenic bacteria cocktail coexist situation. In this study, the behavior of four V. parahaemolyticus strains (F18: tlh+/trh+/tdh−, ATCC 17802: tlh+/trh+/tdh−, F36: tlh+/trh−/tdh−, ATCC 33847: tlh+/trh−/tdh+) and their cocktails on cooked shrimp were investigated at different temperatures (4, 7, 10, 15, 20, 25 and 30 °C). Total bacteria counts were enumerated by traditional plate count method, periodically. Results showed both V. parahaemolyticus cocktails and four single strains grew in a temperature range of 15–30 °C and died at 4–7 °C. At 10 °C, for the cocktails, it inactivated at initial 100 h and then grew rapidly; but for single strain, only one strain F18 displayed the similar growth tendency, while the others grew all the time. Compared with single strains, the primary and secondary model analysis showed that the cocktails displayed a better growth activity with higher maximum growth rate and shorter lag time. The above results indicated that modeling bacterial growth by using a cocktail of V. parahaemolyticus strains may be a better option for simulating growth in the real environment. This study will fill in the gap of predictive microbiology and improve significantly the accuracy of microbial risk assessment.

Intravaginal probiotics modulated metabolic status and improved milk production and composition of transition dairy cows.

The objective of this investigation was to evaluate whether intravaginal infusion of probiotics (a lactic acid bacteria cocktail) around parturition would influence metabolic status and increase milk production of transition dairy cows. One hundred pregnant Holstein dairy cows were assigned to 1 of the 3 experimental groups receiving intravaginal infusion of probiotics or carrier (i.e., sterile skim milk) once a week at wk -2, -1, and +1 relative to calving as follows: 2 consecutive probiotics before parturition and 1 carrier dose after parturition (TRT1), 3 consecutive probiotics doses around parturition (TRT2), and 3 consecutive carrier doses around parturition (CTR). The probiotics were a lyophilized culture mixture composed of FUA3089 and FUA3138 and FUA3140 with a cell count of 10 to 10 cfu/dose. Blood was sampled from wk -2 to +3 and milk was sampled on the third day in milk (DIM) and from wk +1 to +5 on a weekly basis. Feed intake and milk production was monitored until wk +8. Results showed that the TRT2 group (366.12 ± 49.77 μmol/L) had a lower ( = 0.01) concentration of NEFA in the serum than the CTR group (550.85 ± 47.16 μmol/L). The concentrations of IgG in the milk were 32.71 ± 3.00 mg/mL in the TRT1 group, 17.47 ± 4.54 mg/mL in the TRT2 group, and 6.73 ± 3.43 mg/mL in the CTR group at 3 DIM ( < 0.01). Meanwhile, both the TRT1 and the TRT2 group had lower haptoglobin in the milk compared with the CTR group at 3 DIM ( < 0.01). The TRT1 group had greater milk protein content than the CTR group (2.99 ± 0.04 vs. 2.82 ± 0.04%; = 0.02), whereas the TRT2 group tended to have greater lactose content compared with the CTR group (4.53 ± 0.03 vs. 4.44 ± 0.03%; = 0.05). The effect of treatment interacted with parity with regards to milk production and feed efficiency. Multiparous cows in the TRT1 and TRT2 groups had greater milk production and feed efficiency than those in the CTR group ( < 0.01 and = 0.02, respectively). Among primiparous cows, those in the TRT2 group had greater milk production ( = 0.04) whereas those in the TRT1 group had lower feed intake ( < 0.01) than those in the CTR group. Both the TRT1 and the TRT2 groups had enhanced feed efficiency compared with the CTR group ( < 0.01). In conclusion, intravaginal infusion of lactic acid bacteria modulated concentrations of selected serum metabolites and milk components and increased milk efficiency of transition dairy cows.

Soil Solarization and Biological Control for Managing Mesocriconema xenoplax and Short Life in a Newly Established Peach Orchard.

The effects of soil solarization, with and without a Pseudomonas spp. cocktail or wheat rotation as alternatives to chemical control of Mesocriconema xenoplax, were investigated from 2004 to 2011. Preplant solarization and soil fumigation (67% methyl bromide + 33% chloropicrin mixture; henceforth, referred to as MBr) was initiated in 2004 in an orchard infested with M. xenoplax and a history of peach tree short life (PTSL). Plots consisted of nine treatments: (i) nonsolarized soil-alone, (ii) nonsolarized soil with bacteria cocktail (nonsolar-bacteria), (iii) nonsolarized soil with wheat (nonsolar-wheat), (iv) nonsolarized soil with bacteria cocktail and wheat (nonsolar-bacteria-wheat), (v) solarized soil-alone, (vi) solarized soil with bacteria cocktail solar-bacteria), (vii) solarized soil with wheat (solar-wheat), (viii) solarized soil with bacteria cocktail and wheat (solar-bacteria-wheat), and (ix) preplant MBr fumigation. Peach trees were planted into all plots in 2005. Nematode populations were suppressed 20 months longer after orchard establishment in solar-alone and solar-wheat plots than solar-bacteria and solar-bacteria-wheat plots. Pseudomonas spp. cocktails did not have a pronounced effect in suppressing M. xenoplax in this study. Fumigation effect on M. xenoplax population density dissipated 24 months after application. Solar-wheat-treated soil was as effective as preplant MBr fumigation in increasing tree survival from PTSL for at least 6 years after orchard establishment.

Nanoparticles for Rapid Detection of Microbial Threats

NanomedicineVol. 6, No. 8 EditorialNanoparticles for rapid detection of microbial threatsXiaoning Li & Vincent M RotelloXiaoning LiDepartment of Chemistry, University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01003, USASearch for more papers by this author & Vincent M Rotello† Author for correspondenceDepartment of Chemistry, University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01003, USA. Search for more papers by this authorEmail the corresponding author at rotello@chem.umass.eduPublished Online:25 Oct 2011https://doi.org/10.2217/nnm.11.129AboutSectionsView ArticleView Full TextPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinkedInReddit View article"Nanoparticles for rapid detection of microbial threats." , 6(8), pp. 1295–1296Keywords: biosensorsmicrobial detectionnanoparticlesBibliography1 Allen MJ, Edberg SC, Reasoner DJ. Heterotrophic plate count bacteria – what is their significance in drinking water? Int. J. Food Microbiol.92,265–274 (2004).Crossref, Medline, Google Scholar2 Burtscher C, Wuertz S. Evaluation of the use of PCR and reverse transcriptase PCR for detection of pathogenic bacteria in biosolids from anaerobic digestors and aerobic composters. Appl. Environ. Microbiol.69,4618–4627 (2003).Crossref, Medline, CAS, Google Scholar3 Van Dyck E, Ieven M, Pattyn S, Van Damme L, Laga M. Detection of Chlamydia trachomatis and Neisseria gonorrhoeae by enzyme immunoassay, culture, and three nucleic acid amplification tests. J. Clin. Microbiol.39,1751–1756 (2001).Crossref, Medline, CAS, Google Scholar4 Mao XL, Yang LJ, Su XL, Li YB. A nanoparticle amplification based quartz crystal microbalance DNA sensor for detection of Escherichia coli O157:H7. Biosens. Bioelectron.21,1178–1185 (2006).Crossref, Medline, CAS, Google Scholar5 Ravindranath SP, Mauer LJ, Deb-Roy C, Irudayaraj J. Biofunctionalized magnetic nanoparticle integrated mid-infrared pathogen sensor for food matrixes. Anal. Chem.81,2840–2846 (2009).Crossref, Medline, CAS, Google Scholar6 Lee H, Sun E, Ham D, Weissleder R. Chip-NMR biosensor for detection and molecular analysis of cells. Nat. Med.14,869–874 (2008).Crossref, Medline, Google Scholar7 Ji J, Schanzle A, Tabacco MB. Real-time detection of bacterial contamination in dynamic aqueous environments using optical sensors. Anal. Chem.76,1411–1418 (2004).Crossref, Medline, CAS, Google Scholar8 You CC, Miranda OR, Rotello VM et al. Detection and identification of proteins using nanoparticle-fluorescent polymer ‘chemical nose’ sensors. Nat. Nanotech.2,318–323 (2007).Crossref, Medline, CAS, Google Scholar9 Phillips RL, Miranda OR, You CC, Rotello VM, Bunz UHF. Rapid and efficient identification of bacteria using gold-nanoparticle – poly(para-phenyleneethynylene) constructs. Angew. Chem. Int. Ed.47,2590–2594 (2008).Crossref, Medline, CAS, Google Scholar10 Miranda OR, Li X, Rotello VM, Bunz UHF et al. Colorimetric bacteria sensing using a supramolecular enzyme-nanoparticle biosensor. J. Am. Chem. Soc.133,9650–9653 (2011).Crossref, Medline, CAS, Google ScholarFiguresReferencesRelatedDetailsCited ByFast label-free identification of bacteria by synchronous fluorescence of amino acids7 September 2021 | Analytical and Bioanalytical Chemistry, Vol. 413, No. 27Water Disinfection Using Silver and Zinc Oxide Nanoparticles30 August 2021 | Journal of Nano Research, Vol. 69Polycyclic Aromatic Hydrocarbons (PAHs) in inland aquatic ecosystems: Perils and remedies through biosensors and bioremediationEnvironmental Pollution, Vol. 241Colorimetric enumeration of bacterial contamination in water based on β-galactosidase gold nanoshell activityEnzyme and Microbial Technology, Vol. 99Organic chemistry meets polymers, nanoscience, therapeutics and diagnostics2 August 2016 | Beilstein Journal of Organic Chemistry, Vol. 12Multiple strategies to activate gold nanoparticles as antibioticsNanoscale, Vol. 5, No. 18 Vol. 6, No. 8 Follow us on social media for the latest updates Metrics Downloaded 428 times History Published online 25 October 2011 Published in print October 2011 Information© Future Medicine LtdKeywordsbiosensorsmicrobial detectionnanoparticlesFinancial & competing interests disclosureSupport of the NIH (GM077173-05) is gratefully acknowledged. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.No writing assistance was utilized in the production of this manuscript.PDF download

Biofunctionalized Magnetic Nanoparticle Integrated Mid-Infrared Pathogen Sensor for Food Matrixes

Magnetic nanoparticles functionalized with anti-Escherichia coli O157:H7 or anti-Salmonella typhimurium antibodies that can specifically bind to their target organisms were used to isolate E. coli O157:H7 and S. typhimurium separately from a cocktail of bacteria and from food matrixes. The pathogens were then detected using label-free IR fingerprinting. The binding and detection protocol was first validated using a benchtop FT-IR spectrometer and then applied to a portable mid-IR spectrometer to enable this approach as a point-of-detection technology. Highly selective detection was achieved in less than 30 min at both species (E. coli O157:H7 vs S. typhimurium ) and strain (E. coli O157:H7 vs E. coli K12) levels in complex food matrixes (2% milk, spinach extract) with a detection limit of 10(4)-10(5) CFU/mL. The combined approach of functionalized magnetic nanoparticles and IR spectroscopy imparts specificity through spectroscopic fingerprinting and selectivity through species-specific antibodies with an in-built sample extraction step and could be applied in the field for on-site food-borne pathogen monitoring.