scholarly journals Microbial Ecology of Retail Ready-to-Eat Escarole and Red Chicory Sold in Palermo City, Italy

2019 ◽  
Author(s):  
N. Francesca ◽  
R. Guarcello ◽  
V. Craparo ◽  
G. Moschetti ◽  
L. Settanni ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Microbial Ecology ◽  
Pathogenic Bacteria ◽  
Quality Parameters ◽  
Rrna Gene ◽  
Expiry Date ◽  
Spoilage Bacteria ◽  
Genotype By Sequencing ◽  
Analysis System ◽  
Microbial Groups

Background: Ready-To-Eat (RTE) foods include any edible food that is commonly consumed raw. This study aimed at evaluation of microbial ecology of retail RTE escarole and red chicory sold in Palermo city, Italy. Methods: A total of 32 mono-varietal RTE samples, including escarole (n=16) and red chicory (n=16) samples were obtained from Palermo, Italy. Both RTE vegetables at expiry date were analyzed to quantify spoilage bacteria, pathogenic bacteria, and yeast. All different colonies were isolated and identified on the basis of phenotypic characteristics and genetic polymorphisms by random amplification of polymorphic DNA-Polymerase Chain Reaction (PCR) and further genotype by sequencing the 16S rRNA gene. The statistical analysis was conducted with SAS 9.2 software (Statistical Analysis System Institute Inc., Cary, NC, USA). Results: The level of Listeria monocytogenes and coagulase-positive staphylococci were below the detection. Total microbial counts were above 8 log10 colony forming unit/g in RTE red chicory, while they were about 1 log cycle lower in escarole. In general, escarole showed lower levels for all microbial groups than red chicory with the exception of the total yeast. A total of 13 strains were identified into ten species belonging to six genera as Bacillus, Erwinia, Pantoea, Pseudomonas, Microbacterium, and Rahnella. The most numerous identified genera were Pseudomonas and Pantoea. Conclusion: This work pointed out the relevance of implementing good hygiene practices during processing in order to prolong quality parameters and acceptability of mono-varietal salads.

scholarly journals Isolation and Identification of a Paenibacillus polymyxa Strain That Coproduces a Novel Lantibiotic and Polymyxin

2006 ◽  
Vol 73 (1) ◽  
pp. 168-178 ◽  
Author(s):  
Zengguo He ◽  
Duygu Kisla ◽  
Liwen Zhang ◽  
Chunhua Yuan ◽  
Kari B. Green-Church ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Water Solubility ◽  
Fermentation Broth ◽  
Paenibacillus Polymyxa ◽  
Biochemical Properties ◽  
Rrna Gene ◽  
Isolation And Identification ◽  
Gram Positive ◽  
Gram Negative ◽  
Spoilage Bacteria

ABSTRACT A new bacterial strain, displaying potent antimicrobial properties against gram-negative and gram-positive pathogenic bacteria, was isolated from food. Based on its phenotypical and biochemical properties as well as its 16S rRNA gene sequence, the bacterium was identified as Paenibacillus polymyxa and it was designated as strain OSY-DF. The antimicrobials produced by this strain were isolated from the fermentation broth and subsequently analyzed by liquid chromatography-mass spectrometry. Two antimicrobials were found: a known antibiotic, polymyxin E1, which is active against gram-negative bacteria, and an unknown 2,983-Da compound showing activity against gram-positive bacteria. The latter was purified to homogeneity, and its antimicrobial potency and proteinaceous nature were confirmed. The antimicrobial peptide, designated paenibacillin, is active against a broad range of food-borne pathogenic and spoilage bacteria, including Bacillus spp., Clostridium sporogenes, Lactobacillus spp., Lactococcus lactis, Leuconostoc mesenteroides, Listeria spp., Pediococcus cerevisiae, Staphylococcus aureus, and Streptococcus agalactiae. Furthermore, it possesses the physico-chemical properties of an ideal antimicrobial agent in terms of water solubility, thermal resistance, and stability against acid/alkali (pH 2.0 to 9.0) treatment. Edman degradation, mass spectroscopy, and nuclear magnetic resonance were used to sequence native and chemically modified paenibacillin. While details of the tentative sequence need to be elucidated in future work, the peptide was unequivocally characterized as a novel lantibiotic, with a high degree of posttranslational modifications. The coproduction of polymyxin E1 and a lantibiotic is a finding that has not been reported earlier. The new strain and associated peptide are potentially useful in food and medical applications.

scholarly journals First reported quantitative microbiota in different livestock manures used as organic fertilizers in the Northeast of Thailand

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lampet Wongsaroj ◽  
Ratmanee Chanabun ◽  
Naruemon Tunsakul ◽  
Pinidphon Prombutara ◽  
Somsak Panha ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Organic Fertilizer ◽  
The Other ◽  
Organic Fertilizers ◽  
Rrna Gene ◽  
Bacterial Composition ◽  
Physiochemical Properties ◽  
Nutrient Profiles ◽  
Soil Recovery ◽  
Local Farmers

AbstractNortheastern Thailand relies on agriculture as a major economic activity, and has used high levels of agrochemicals due to low facility, and salty sandy soil. To support soil recovery and sustainable agriculture, local farmers have used organic fertilizers from farmed animal feces. However, knowledge about these animal fecal manures remains minimal restricting their optimal use. Specifically, while bacteria are important for soil and plant growth, an abundance and a diversity of bacterial composition in these animal fecal manures have not been reported to allow selection and adjustment for a more effective organic fertilizer. This study thereby utilized metagenomics combined with 16S rRNA gene quantitative PCR (qPCR) and sequencing to analyze quantitative microbiota profiles in association with nutrients (N, P, K), organic matters, and the other physiochemical properties, of the commonly used earthworm manure and other manures from livestock animals (including breed and feeding diet variations) in the region. Unlike the other manures, the earthworm manure demonstrated more favorable nutrient profiles and physiochemical properties for forming fertile soil. Despite low total microbial biomass, the microbiota were enriched with maximal OTUs and Chao richness, and no plant pathogenic bacteria were found based on the VFDB database. The microbial metabolic potentials supported functions to promote crop growth, such as C, N and P cyclings, xenobiotic degradation, and synthesis of bioactive compounds. Pearson’s correlation analyses indicated that the quantitative microbiota of the earthworm manure were clustered in the same direction as N, and conductivity, salinity, and water content were essential to control the microbiota of animal manures.

scholarly journals Utility of the optical quality analysis system for decision-making in Nd: YAG laser posterior capsulotomy in patients with light posterior capsule opacity

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Bo Lu ◽  
Weijie Zhu ◽  
Yu Fan ◽  
Dong Shi ◽  
Liwei Ma
Keyword(s):  
Area Under The Curve ◽  
Quality Parameters ◽  
Optical Quality ◽  
Quality Analysis ◽  
Posterior Capsule ◽  
Clinical Trial Registry ◽  
Posterior Capsulotomy ◽  
Significant Difference ◽  
Analysis System ◽  
Scattering Index

Abstract Background A prospective cohort study was performed to evaluate whether the Optical Quality Analysis System (OQAS) can serve as a valuable additional indicator for appropriate posterior capsulotomy referral. Methods One hundred and five eyes from 96 patients undergoing capsulotomy were divided into precapsulotomy logMAR CDVA ≤0.1 group and logMAR CDVA > 0.1 group. CDVA, and the Visual Function 14 index (VF-14) score were estimated before and 1 month after capsulotomy. The objective scattering index (OSI) value was measured by using the OQAS. Posterior capsule opacification (PCO) severity was assessed with Evaluation of PCO 2000 (EPCO 2000) software. Results In logMAR CDVA > 0.1 group, the correlations of OSI, logMAR CDVA, EPCO score and VF-14 score were very strong preoperatively. In logMAR CDVA ≤0.1 group, preoperatively, OSI was correlated with logMAR CDVA (r = 0.451), EPCO score (r = 0.789), and VF-14 score (r = 0.852). LogMAR CDVA has weak correlation with VF-14 score (r = − 0.384) and EPCO score (r = 0.566). VF-14 score was correlated with EPCO score (r = − 0.669). In the logMAR CDVA ≤0.1 group, there was no significant difference in logMAR CDVA between precapsulotomy and postcapsulotomy (P > 0.05). In the two groups, all the other optical quality parameters were significantly improved after capsulotomy (P < 0.05). In logMAR CDVA > 0.1 group, the area under the curve of the ROC of the OSI was 0.996 (P = 0.000). In logMAR CDVA ≤0.1 group, the area under the curve of the ROC of the OSI was 0.943 (P = 0.000). Conclusions The OSI was useful for evaluating of PCO and prediction of beneficial capsulotomy. Especially for patients with slight PCO and better visual acuity, OSI is more valuable than CDVA and completely objective examination. Trial registration The study protocol was registered at the Chinese Clinical Trial Registry. Register: ChiCTR1800018842 (Registered Date: October 13th, 2018).

Statistical analysis and physicochemical characteristics of groundwater ‎quality parameters: a case study

2021 ◽  
pp. 1-22
Author(s):  
Yaqoob Iqbal Memon ◽  
Sundus Saeed Qureshi ◽  
Imdad Ali Kandhar ◽  
Naeem Ahmed Qureshi ◽  
Sumbul Saeed ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Groundwater Quality ◽  
Physicochemical Characteristics ◽  
Quality Parameters

scholarly journals Identification of an N-acetylneuraminic acid-presenting bacteria isolated from a human microbiome

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zhen Han ◽  
Peter S. Thuy-Boun ◽  
Wayne Pfeiffer ◽  
Vincent F. Vartabedian ◽  
Ali Torkamani ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Human Microbiome ◽  
Host Immunity ◽  
Rrna Gene ◽  
Metabolic Labeling ◽  
Selective Labeling ◽  
Fecal Microbiome ◽  
Acetylneuraminic Acid ◽  
Intestinal Mucus ◽  
Microbial Systems

AbstractN-Acetylneuraminic acid is the most abundant sialic acid (SA) in humans and is expressed as the terminal sugar on intestinal mucus glycans. Several pathogenic bacteria harvest and display host SA on their own surfaces to evade Siglec-mediated host immunity. While previous studies have identified bacterial enzymes associated with SA catabolism, no reported methods permit the selective labeling, tracking, and quantitation of SA-presenting microbes within complex multi-microbial systems. We combined metabolic labeling, click chemistry, 16S rRNA gene, and whole-genome sequencing to track and identify SA-presenting microbes from a cultured human fecal microbiome. We isolated a new strain of Escherichia coli that incorporates SA onto its own surface and encodes for the nanT, neuA, and neuS genes necessary for harvesting and presenting SA. Our method is applicable to the identification of SA-presenting bacteria from human, animal, and environmental microbiomes, as well as providing an entry point for the investigation of surface-expressed SA-associated structures.

scholarly journals The Growth of Leaf Lettuce and Bacterial Communities in a Closed Aquaponics System with Catfish

Horticulturae ◽  
2021 ◽  
Vol 7 (8) ◽  
pp. 222
Author(s):  
Kenji Yamane ◽  
Yuuki Kimura ◽  
Keita Takahashi ◽  
Isamu Maeda ◽  
Masayuki Iigo ◽  
...  
Keyword(s):  
Plant Growth ◽  
Early Stage ◽  
Amplicon Sequencing ◽  
Small Scale ◽  
Rrna Gene ◽  
Culture Solution ◽  
Beneficial Effects ◽  
Sustainable Cultivation ◽  
Microbial Groups ◽  
Production Period

Aquaponics is a circulating and sustainable system that combines aquaculture and hydroponics and forms a symbiotic relationship between fish, plants, and microorganisms. We hypothesized that feed alone could support plant growth, but the symbiosis with fish adds some beneficial effects on plant growth in aquaponics. In this study, we created three closed culture systems, namely, aquaponics, hydroponics without nitrogen (N) and phosphorus (P), and aquaculture, and added the same amount of feed containing N and P to all the treatments in order to test the hypothesis. Accumulation of NO3− and PO43− was alleviated in aquaponics and hydroponics as a result of plant uptake. Lettuce plants grown in aquaponics grew vigorously until 2 weeks and contained a constant level of N in plants throughout the production period, whereas those in hydroponics grew slowly in the early stage and then vigorously after 2 weeks with a late increment of N concentration. These results suggest that catfish help with the faster decomposition of the feed, but, in hydroponics, feed can be slowly dissolved and decomposed owing to the absence of the fish. The bacterial community structures of the culture solution were investigated using 16S rRNA gene amplicon sequencing. At the class level, Actinobacteria, Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria were the major microbial groups in the solutions. Aquaponics prevented the pollution of tank solution and maintained a higher water quality compared with hydroponics and aquaculture, suggesting that aquaponics is a more sustainable cultivation system even in a small-scale system.

scholarly journals Detection of Food Spoilage and Pathogenic Bacteria Based on Ligation Detection Reaction Coupled to Flow-Through Hybridization on Membranes

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
K. Böhme ◽  
P. Cremonesi ◽  
M. Severgnini ◽  
Tomás G. Villa ◽  
I. C. Fernández-No ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Cost Effective ◽  
Rrna Gene ◽  
Bacterial Identification ◽  
Dot Blot ◽  
Culture Collections ◽  
Ligation Detection Reaction ◽  
Flow Through ◽  
Food Safety And Quality

Traditional culturing methods are still commonly applied for bacterial identification in the food control sector, despite being time and labor intensive. Microarray technologies represent an interesting alternative. However, they require higher costs and technical expertise, making them still inappropriate for microbial routine analysis. The present study describes the development of an efficient method for bacterial identification based on flow-through reverse dot-blot (FT-RDB) hybridization on membranes, coupled to the high specific ligation detection reaction (LDR). First, the methodology was optimized by testing different types of ligase enzymes, labeling, and membranes. Furthermore, specific oligonucleotide probes were designed based on the 16S rRNA gene, using the bioinformatic tool Oligonucleotide Retrieving for Molecular Applications (ORMA). Four probes were selected and synthesized, being specific forAeromonasspp.,Pseudomonasspp.,Shewanellaspp., andMorganella morganii, respectively. For the validation of the probes, 16 reference strains from type culture collections were tested by LDR and FT-RDB hybridization using universal arrays spotted onto membranes. In conclusion, the described methodology could be applied for the rapid, accurate, and cost-effective identification of bacterial species, exhibiting special relevance in food safety and quality.

scholarly journals Differences in Microbial Activity and Microbial Populations of Peat Associated with Suppression of Damping-Off Disease Caused by Pythium sylvaticum

2006 ◽  
Vol 72 (10) ◽  
pp. 6452-6460 ◽  
Author(s):  
Paul J. Hunter ◽  
Geoff M. Petch ◽  
Leo A. Calvo-Bado ◽  
Tim R. Pettitt ◽  
Nick R. Parsons ◽  
...  
Keyword(s):  
Microbial Activity ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Small Subunit ◽  
Disease Suppression ◽  
Rrna Gene ◽  
Damping Off ◽  
Small Subunit Rrna ◽  
Pythium Sylvaticum ◽  
Gradient Gel Electrophoresis ◽  
Microbial Groups

ABSTRACT The microbiological characteristics associated with disease-suppressive peats are unclear. We used a bioassay for Pythium sylvaticum-induced damping-off of cress seedlings to identify conducive and suppressive peats. Microbial activity in unconditioned peats was negatively correlated with the counts of P. sylvaticum at the end of the bioassay. Denaturing gradient gel electrophoresis (DGGE) profiling and clone library analyses of small-subunit rRNA gene sequences from two suppressive and two conducive peats differed in the bacterial profiles generated and the diversity of sequence populations. There were also significant differences between bacterial sequence populations from suppressive and conducive peats. The frequencies of a number of microbial groups, including the Rhizobium-Agrobacterium group (specifically sequences similar to those for the genera Ochrobactrum and Zoogloea) and the Acidobacteria, increased specifically in the suppressive peats, although no single bacterial group was associated with disease suppression. Fungal DGGE profiles varied little over the course of the bioassay; however, two bands associated specifically with suppressive samples were detected. Sequences from these bands corresponded to Basidiomycete yeast genera. Although the DGGE profiles were similar, fungal sequence diversity also increased during the bioassay. Sequences highly similar to those of Cryptococcus increased in relative abundance during the bioassay, particularly in the suppressive samples. This study highlights the importance of using complementary approaches to molecular profiling of complex populations and provides the first report that basidiomycetous yeasts may be associated with the suppression of Pythium-induced diseases in peats.

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