Comparison of microbial diversity of edible flowers and basil grown with organic versus conventional methods

2010 ◽  
Vol 56 (11) ◽  
pp. 943-951 ◽  
Author(s):  
Kaedra Wetzel ◽  
Jiyoung Lee ◽  
Chang Soo Lee ◽  
Margaret Binkley
Keyword(s):  
Phylogenetic Analysis ◽  
Microbial Diversity ◽  
Diversity Index ◽  
Acinetobacter Calcoaceticus ◽  
Food Samples ◽  
Food Borne ◽  
Food Borne Illness ◽  
Enterobacter Ludwigii ◽  
Enterobacter Asburiae ◽  
Organically Grown

The consumption and use of edible flowers as food is growing; however, no study has been conducted to evaluate their role in the cause of food-borne illness or in food safety. Recent food-borne outbreaks traced to fresh herbs have raised concern about their processing and handling. Basil, one of the most commonly used fresh herbs, has been identified as a source of food-borne illness. Baseline assessments of microflora were performed, and the microbial diversity between growing methods (organic vs. conventional) was compared. DNA sequencing was used to identify the microbial flora present on fresh edible flower and basil samples. The most predominant species identified were Enterobacter hormaechei (10%), Acinetobacter calcoaceticus (10%), Enterobacter ludwigii (10%), Enterobacter asburiae (6%), and Enterobacter cowanii (6%). Pseudomonas aeruginosa (6%), Salmonella enterica (6%), and Bacillus amyloliquefaciens (2%) were also isolated. Phylogenetic analysis showed that most species of isolated bacteria belonged to the phyla Gammaproteobacteria (81.2%) and Firmicutes (18.8%). Statistical analysis, diversity index for species richness, and lineage-per-time plots showed that for basil, organically grown samples had a higher microbial diversity than conventionally grown samples. Edible flowers and basil are often grown using organic methods and are commonly consumed raw without any washing or cooking, to preserve aesthetic value, but these practices may pose a potential risk for food-borne illness. The baseline assessment, together with phylogenetic and statistical analyses, indicated possible microbial contamination in edible flowers and basil. The use of statistical estimation of molecular diversity based on the 16S rRNA sequences and lineage-per-time plots with phylogenetic analysis well served as a means for comparing microbial diversity in food samples between the growing methods (organic vs. conventional).

scholarly journals Development of Methods To Detect “Norwalk-Like Viruses” (NLVs) and Hepatitis A Virus in Delicatessen Foods: Application to a Food-Borne NLV Outbreak

2000 ◽  
Vol 66 (1) ◽  
pp. 213-218 ◽  
Author(s):  
Kellogg J. Schwab ◽  
Frederick H. Neill ◽  
Rebecca L. Fankhauser ◽  
Nicholas A. Daniels ◽  
Stephan S. Monroe ◽  
...  
Keyword(s):  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Internal Standard ◽  
Food Samples ◽  
Viral Rna ◽  
Norwalk Virus ◽  
Specific Primers ◽  
Food Borne ◽  
Common Causes ◽  
Food Borne Illness

ABSTRACT “Norwalk-like viruses” (NLVs) and hepatitis A virus (HAV) are the most common causes of virus-mediated food-borne illness. Epidemiological investigations of outbreaks associated with these viruses have been hindered by the lack of available methods for the detection of NLVs and HAV in foodstuffs. Although reverse transcription (RT)-PCR methods have been useful in detecting NLVs and HAV in bivalve mollusks implicated in outbreaks, to date such methods have not been available for other foods. To address this need, we developed a method to detect NLVs and HAV recovered from food samples. The method involves washing of food samples with a guanidinium-phenol-based reagent, extraction with chloroform, and precipitation in isopropanol. Recovered viral RNA is amplified with HAV- or NLV-specific primers in RT-PCRs, using a viral RNA internal standard control to identify potential sample inhibition. By this method, 10 to 100 PCR units (estimated to be equivalent to 102 to 103 viral genome copies) of HAV and Norwalk virus seeded onto ham, turkey, and roast beef were detected. The method was applied to food samples implicated in an NLV-associated outbreak at a university cafeteria. Sliced deli ham was positive for a genogroup II NLV as determined by using both polymerase- and capsid-specific primers and probes. Sequence analysis of the PCR-amplified capsid region of the genome indicated that the sequence was identical to the sequence from virus detected in the stools of ill students. The developed method is rapid, simple, and efficient.

scholarly journals Bacterial Analysis and Survey of the Street Food of Kathmandu in Relation to Child Health

2015 ◽  
Vol 26 ◽  
pp. 1-9
Author(s):  
R Tuladhar ◽  
Anjana Singh
Keyword(s):  
Bacterial Contamination ◽  
Enterobacter Aerogenes ◽  
Food Samples ◽  
Hygiene Practice ◽  
Street Vendors ◽  
Street Food ◽  
E Coli ◽  
Food Borne ◽  
Food Borne Illness ◽  
Dominant Bacteria

Analysis of street foods of Kathmandu for bacterial contamination was performed in 12 different street foods. The surveillance study was carried in 200 children of primary grade from public school and 12 street vendors for the health hygiene and hazards associated with street food. Poor hygiene practice in preparation and handling of street food has been observed in the vendors. The lack of the knowledge in vendors about the source of bacterial contamination and absence of surveillance on street food has subjected street food to the high potential for food borne illness. The inadequate safety measure adopted by the targeted consumers of street food, the children, has augmented the risk associated with street food. All the food samples analyzed were contaminated with bacteria. The mesophilic count was recorded highest in Panipuri while as coliform count was highest in Chana tarkari. The least count of both was observed in Aaloo chop . Highest number of Staphylococccus aureus was found in Kerau (1.5X103cfu/g) and lowest in Momo (8.3 cfu/g). The dominant bacteria contaminating the food was S. aureus followed by Bacillus alvei, Escherichia coli, Enterobacter aerogenes, Bacillus subtilis, Serratia sp., S. saprophyticus. The contaminated hand and clothing of the person who prepare food are the major source of S. aureus. Highest percentage of E. coli found in Panipuri must be due to the use of contaminated water. Chana chatpate and Chana tarkari were the foods found to be contaminated with Salmonella sp. The type of food and the degree of hygiene practice adopted by vendor refl ects the type and magnitude of bacterial contamination. Implementation of hygienic practices in vendors may reduce the contamination of street food and health education of the school children will curtail the incidences of food borne illness. Periodical monitoring of quality of street food will avoid any future outbreaks of bacterial pathogen.J. Nat. Hist. Mus. Vol. 26, 2012: 1-9

scholarly journals Enterotoxigenicity and Genetic Relatedness of Clostridium perfringens Isolates from Retail Foods in the United States

2003 ◽  
Vol 69 (3) ◽  
pp. 1642-1646 ◽  
Author(s):  
Yuan-Tong Lin ◽  
Ronald Labbe
Keyword(s):  
United States ◽  
Clostridium Perfringens ◽  
Genetic Relatedness ◽  
The United States ◽  
Food Samples ◽  
Gene Probe ◽  
Cell Extracts ◽  
Food Borne ◽  
Food Borne Illness ◽  
The 1960S

ABSTRACT Clostridium perfringens is a leading cause of bacterial food-borne illness in countries where consumption of meat and poultry is high. For example, each year in the United States, this organism is the second or third most common cause of confirmed cases of food-borne illness. Surveys of the incidence of this organism in retail foods were done in the 1960s without regard to whether isolates were enterotoxigenic. It is now known that not all strains of this organism possess the enterotoxin gene responsible for illness. We examined the incidence of this organism in 131 food samples from retail food stores in an area of the northeastern United States. Forty isolates were obtained by using the iron milk method at 45°C, with confirmation by use of motility nitrate and lactose gelatin media. The presence of the C. perfringens enterotoxin (cpe) and alpha toxin (cpa) genes was determined by PCR using previously published primer sequences. All isolates possessed cpa. None of the isolates were identified as carrying the cpe gene by this method or by another method using a digoxigenin-labeled gene probe. Consistent with these results, none of the sporulating-cell extracts contained enterotoxin as determined by reverse passive latex hemagglutination. Pulsed-field gel electrophoresis was used to determine the genetic relatedness of the isolates. About 5% of the isolates were considered to be closely related (2- to 3-band difference). The others were considered to be unrelated to one another. The results demonstrate the rarity of cpe+ strains in retail foods and the genetic diversity among nonoutbreak strains.

scholarly journals Biological Potential of Semi-Purified Enterocin of Enterococcus Sp. Yt3 Against Selected Food Pathogens

2019 ◽  
Vol 35 (5) ◽  
pp. 1584-1596
Author(s):  
Charu Khanna ◽  
Shalini Singh ◽  
Manish Vyas ◽  
Sujata Das
Keyword(s):  
Shelf Life ◽  
Food Samples ◽  
Natural Food ◽  
Local Market ◽  
Potential Health ◽  
Cultural Conditions ◽  
Food Borne ◽  
Biological Potential ◽  
Food Borne Illness ◽  
Life Improvement

The efforts for prevention of food borne illness and infections draw great attention, worldwide. Different methods, both physical as well as chemical, are commonly used for improving shelf life of food, but limited efficiency of physical methods, and potential health hazards associated with chemical methods, have brought biological processes in the limelight. One such natural, environment friendly, highly effective natural food preservants are, bacteriocins. Thus, there is a continuous need for better bacteriocin producers in the search for more effective bacteriocins than what are already available in the market. In the current study, food samples were collected from local market of Jalandhar, Punjab, and evaluated for bacteriocin producing Lactic acid bacteria. Enterococcus sp. YT3 was found to be the most efficient bacteriocin producer among the isolates, with higher bacteriocin activity exhibited by the given strain under optimized cultural conditions. The partially purified bacteriocin have molecular weight between 35kDa & 48kDa, possess pH (2-10) and thermal stability (even at 121o C for 20 minutes), and exhibit biological potential against different bacteria (E. coli, P. aeruginosa, L. monocytogenes, S. aureus and B. subtilis). Future studies will focus on checking different food samples for real time evaluation of shelf life improvement.

scholarly journals Development and Optimization of a Novel Immunomagnetic Separation- Bacteriophage Assay for Detection ofSalmonella enterica Serovar Enteritidis in Broth

2001 ◽  
Vol 67 (1) ◽  
pp. 217-224 ◽  
Author(s):  
Stacy J. Favrin ◽  
Sabah A. Jassim ◽  
Mansel W. Griffiths
Keyword(s):  
Developed Countries ◽  
Immunomagnetic Separation ◽  
Food Samples ◽  
Host Cells ◽  
Target Cells ◽  
Healthy Population ◽  
Technical Ability ◽  
Progeny Phage ◽  
Food Borne ◽  
Food Borne Illness

ABSTRACT Salmonella is the second-leading cause of food-borne illness in most developed countries, causing diarrhea, cramps, vomiting, and often fever. Many rapid methods are available for detection of Salmonella in foods, but these methods are often insensitive or expensive or require a high degree of technical ability to perform. In this paper we describe development and characterization of a novel assay that utilizes the normal infection cycle of bacteriophage SJ2 for detection of Salmonella enterica serovar Enteritidis in broth. The assay consists of four main stages: (i) capture and concentration of target cells by using immunomagnetic separation (IMS); (ii) infection of the target bacterium with phage; (iii) amplification and recovery of progeny phage; and (iv) assay of progeny phage on the basis of their effect on a healthy population of host cells (signal-amplifying cells). The end point of the assay can be determined by using either fluorescence or optical density measurements. The detection limit of the assay in broth is less than 104 CFU/ml, and the assay can be performed in 4 to 5 h. The results of this study demonstrate that the IMS-bacteriophage assay is a rapid, simple, and sensitive technique for detection of Salmonella serovar Enteritidis in broth cultures which can be applied to preenriched food samples.

scholarly journals Microbial Profile of Fresh Beef Sold in the Markets of Ngaoundéré, Cameroon, and Antiadhesive Activity of a Biosurfactant against Selected Bacterial Pathogens

2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
Hippolyte T. Mouafo ◽  
Annick M. B. Baomog ◽  
Jorelle J. B. Adjele ◽  
Alphonse T. Sokamte ◽  
Augustin Mbawala ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Microbial Diversity ◽  
Salmonella Enteritidis ◽  
Meat Industry ◽  
Microbial Profile ◽  
Meat Spoilage ◽  
Food Borne ◽  
Food Borne Illness ◽  
Microbiological Criteria ◽  
Potential Use

Owing to its composition, meat is recognized as one of the best media for microbial growth leading to meat spoilage and food-borne illness. The ability of microorganisms to adhere to surfaces where meat is deposited during selling is a nonnegligible cause of meat contamination. This work was performed to assess the microbial profile of fresh beef sold in the markets of Ngaoundéré town and evaluate the antiadhesive activity of a biosurfactant derived from Lactobacillus paracasei subsp. tolerans N2 against selected pathogenic strains isolated in fresh beef. All fresh beef samples analysed were contaminated with both pathogenic and spoilage microorganisms at levels higher than the microbiological criteria set by the European Commission. A total of 151 strains belonging to 12 species (Pseudomonas putida, Pseudomonas aeruginosa, Pseudomonas sp., Escherichia coli 1, Escherichia coli, Salmonella enteritidis, Salmonella sp., Staphylococcus epidermidis, Staphylococcus xylosus, Staphylococcus aureus, Candida albicans, and Candida sp.) were isolated and identified. A specific relationship between the microbial diversity of fresh beef and the sampling sites was observed. Biosurfactant displayed antiadhesive activity against all the tested strains and the complete inhibition (100%) of Bacillus sp. BC1, S. aureus STP1, and S. xylosus STP2 was noticed at biosurfactant concentration of 10 mg/mL. This study indicates the microbial diversity of fresh beef sold in Ngaoundéré markets and suggests the potential use of biosurfactant as an antiadhesive agent in the meat industry.

Food-borne Illness Surveillance and Etiology of Diarrhea in Bangladesh

2018 ◽  
Author(s):  
Mohammad Afzalur Rahman ◽  
M Flora ◽  
M Rahman ◽  
M Billah
Keyword(s):  
Food Borne ◽  
Food Borne Illness

scholarly journals In Silico Characterization of Toxin-Antitoxin Systems in Campylobacter Isolates Recovered from Food Sources and Sporadic Human Illness

Genes ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 72
Author(s):  
Bishoy Wadie ◽  
Mohamed A. Abdel-Fattah ◽  
Alshymaa Yousef ◽  
Shaimaa F. Mouftah ◽  
Mohamed Elhadidy ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
In Silico ◽  
Antimicrobial Agents ◽  
Food Sources ◽  
Model Organisms ◽  
Food Borne ◽  
Food Borne Illness ◽  
Human Illness ◽  
Clonal Population Structure ◽  
In Silico Characterization

Campylobacter spp. represents the most common cause of gastroenteritis worldwide with the potential to cause serious sequelae. The ability of Campylobacter to survive stressful environmental conditions has been directly linked with food-borne illness. Toxin-antitoxin (TA) modules play an important role as defense systems against antimicrobial agents and are considered an invaluable strategy harnessed by bacterial pathogens to survive in stressful environments. Although TA modules have been extensively studied in model organisms such as Escherichia coli K12, the TA landscape in Campylobacter remains largely unexplored. Therefore, in this study, a comprehensive in silico screen of 111 Campylobacter (90 C.jejuni and 21 C.coli) isolates recovered from different food and clinical sources was performed. We identified 10 type II TA systems belonging to four TA families predicted in Campylobacter genomes. Furthermore, there was a significant association between the clonal population structure and distribution of TA modules; more specifically, most (12/13) of the Campylobacter isolates belonging to ST-21 isolates possess HicB-HicA TA modules. Finally, we observed a high degree of shared synteny among isolates bearing certain TA systems or even coexisting pairs of TA systems. Collectively, these findings provide useful insights about the distribution of TA modules in a heterogeneous pool of Campylobacter isolates from different sources, thus developing a better understanding regarding the mechanisms by which these pathogens survive stressful environmental conditions, which will further aid in the future designing of more targeted antimicrobials.

Sign in / Sign up

Export Citation Format

Share Document