scholarly journals Evaluation of the FecalSwab for Stool Specimen Storage and Molecular Detection of Enteropathogens on the BD Max System

2020 ◽  
Vol 58 (9) ◽  
Author(s):  
Melissa Richard-Greenblatt ◽  
Candy Rutherford ◽  
Kathy Luinstra ◽  
Ana María Cárdenas ◽  
Xiaoli Lilly Pang ◽  
...  
Keyword(s):  
Molecular Detection ◽  
Stool Specimen ◽  
Storage Temperature ◽  
Enteric Bacteria ◽  
Detection Sensitivity ◽  
Clinical Microbiology Laboratory ◽  
Sample Storage ◽  
Specimen Type ◽  
Stool Specimens ◽  
The Stability

ABSTRACT The FecalSwab system (Copan Italia, Brescia, Italy) is a convenient alternative to bulk stool for the diagnosis of enteric pathogens. Although the U.S. Food and Drug Administration (FDA) approved for transport and culture of enteric bacterial pathogens, the FecalSwab has not been well assessed for its suitability with molecular platforms. In this study, we evaluated the FecalSwab as a specimen type for the BD Max system using the viral and bacterial enteric panels (BD Diagnostics, Baltimore, MD, USA). A total of 186 unpreserved stool specimens were collected and used to prepare matched bulk stool and FecalSwab samples. Performance was equivalent (P > 0.48) to bulk stool for all targets when 50 μl of FecalSwab specimen was loaded onto the BD Max assays. As stool specimens are often collected off-site from the clinical microbiology laboratory and require transport, we assessed the stability of stool specimens stored for up to 14 days at 4°C, 22°C, or 35°C to account for varying transportation conditions. Molecular detection for the majority of viral targets (excluding astrovirus) was unaffected (change in cycle threshold [ΔCT] ≤ 1) by sample storage temperature over the 2-week period; however, detection of enteric bacteria was variable if specimens were not refrigerated (22°C or 35°C). By demonstrating equivalent performance to matched bulk stool and maintaining molecular detection sensitivity when stored at 4°C, we suggest that the FecalSwab is a suitable specimen type for enteropathogen diagnostics on the BD Max system.

Stability of Cocaine Compounds in Biological Fluids During Post-Analytical Sample Storage

2020 ◽  
Vol 44 (8) ◽  
pp. 864-870
Author(s):  
Teresa Huertas ◽  
Carmen Jurado ◽  
Manuel Salguero ◽  
Teresa Soriano ◽  
Joaquin Gamero
Keyword(s):  
Storage Temperature ◽  
Biological Fluids ◽  
Urine Samples ◽  
Sample Storage ◽  
Blood Samples ◽  
Percent Recovery ◽  
The Stability ◽  
The Impact ◽  
In Vitro Stability

Abstract The objective of this study is to evaluate in vitro stability of cocaine compounds, cocaine (COC), benzoylecgonine (BE), ecgonine methyl ester (EME) and benzoylecgonine ethyl ester (EBE), in blood and urine, during post-analysis custody. Stability was evaluated by measuring percent recovery. Parameters evaluated were time of custody (1 year), storage temperature (−20°C and 4°C), influence of preservative (only for blood samples) and pH (only for urine samples). The impact of the temperature is very important in blood samples. At −20°C all compounds demonstrated to be stable, with recoveries higher than 80% after 1 year. In contrast, degradation was observed in the concentration for all four compounds when the samples were maintained at 4°C. In these same conditions, the influence of the preservative was also noticeable and a higher stability was found in samples preserved with NaF. COC and EBE had similar profiles, and both compounds disappeared after 30 days in samples without NaF and after 150 days in samples with NaF added. EME disappeared after 185 days and after 215 days in samples without and with preservative, respectively. BE recoveries, after 365 days of storage, were 68.5% (in samples with NaF) and 3.7% (in samples without NaF). In urine samples, the four compounds were stable in all the studied conditions except when samples were at pH 8 and stored at 4°C where the compounds disappeared (COC and EBE after 75 days of storage and EME after 15 days). The exception was BE, with a recovery of 23% after 1 year of storage. Of the temperatures evaluated, −20°C seems to be optimal for storage to maintain the stability of cocaine and metabolites in biological samples. This can be further enhanced by maintaining a pH of 4 in urine samples and adding a NaF preservative to blood.

scholarly journals The Effect of pH and Storage Temperature on the Stability of Emulsions Stabilized by Rapeseed Proteins

Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1657
Author(s):  
Karolina Östbring ◽  
María Matos ◽  
Ali Marefati ◽  
Cecilia Ahlström ◽  
Gemma Gutiérrez
Keyword(s):  
Zeta Potential ◽  
Storage Temperature ◽  
Emulsion Stability ◽  
Press Cake ◽  
Strong Impact ◽  
Soy Lecithin ◽  
Rapeseed Protein ◽  
Rapeseed Proteins ◽  
Precipitation Ph ◽  
The Stability

Rapeseed press cake (RPC), the by-product of rapeseed oil production, contains proteins with emulsifying properties, which can be used in food applications. Proteins from industrially produced RPC were extracted at pH 10.5 and precipitated at pH 3 (RPP3) and 6.5 (RPP6.5). Emulsions were formulated at three different pHs (pH 3, 4.5, and 6) with soy lecithin as control, and were stored for six months at either 4 °C or 30 °C. Zeta potential and droplet size distribution were analyzed prior to incubation, and emulsion stability was assessed over time by a Turbiscan instrument. Soy lecithin had significantly larger zeta potential (−49 mV to 66 mV) than rapeseed protein (−19 mV to 20 mV). Rapeseed protein stabilized emulsions with smaller droplets at pH close to neutral, whereas soy lecithin was more efficient at lower pHs. Emulsions stabilized by rapeseed protein had higher stability during storage compared to emulsions prepared by soy lecithin. Precipitation pH during the protein extraction process had a strong impact on the emulsion stability. RPP3 stabilized emulsions with higher stability in pHs close to neutral, whereas the opposite was found for RPP6.5, which stabilized more stable emulsions in acidic conditions. Rapeseed proteins recovered from cold-pressed RPC could be a suitable natural emulsifier and precipitation pH can be used to monitor the stability in emulsions with different pHs.

PRODUCTION OF GRANULATED INSTANT KISSEL BASED ON WHEY AND VEGETABLE RAW MATERIALS

2020 ◽  
Author(s):  
А.Л. Майтаков ◽  
Л.Н. Берязева ◽  
Н.Т. Ветрова ◽  
К.Б. Плотников
Keyword(s):  
Storage Temperature ◽  
Raw Materials ◽  
Storage Period ◽  
Technical Documentation ◽  
Plant Raw Materials ◽  
Temperature Conditions ◽  
Aronia Melanocarpa ◽  
Organoleptic Characteristics ◽  
Local Plant ◽  
The Stability

Разработан новый быстрорастворимый продукт (кисель) с определенным фазовым составом и строением на основе молочной сыворотки и местного растительного сырья – черноплодной рябины (Aronia melanocarpa). Разработана модель технологии производства быстрорастворимого гранулированного продукта (кисель) на основе молочной сыворотки и черноплодной рябины. Исследована сохраняемость киселя в трех температурных режимах: 1-й (21 ± 1)°С; 2-й с низкой плюсовой температурой (5 ± 1)°С; 3-й с повышенной (39 ± 1)°С при влажности окружающей среды 80%. По окончании годичного исследования сохраняемости при температурных режимах (21 ± 1)°С и (5 ± 1)°С изменений в органолептических показателях продукта не наблюдали. Скорость растворения продукта при температурных условиях хранения (21 ± 1)°С и (5 ± 1)°С не изменялась на протяжении 9 мес. Установлено, что при хранении в условиях пониженных положительных температур 4–6°С и в режиме комнатной температуры (21 ± 1)°С исследуемый пищеконцентрат по окончании 6 мес. хранения не изменил свойств по показателям качества. Сроки испытания продукта превышали по длительности в 2 раза заданный срок хранения (коэффициент запаса). Результаты испытаний явились основанием для разработки технической документации на производство быстрорастворимых гранулированных плодово-ягодных киселей. A new fast – soluble product (kissel) with a certain phase composition and structure based on whey and local plant raw materials Aronia melanocarpa. A model of technology for the production of a rapidly soluble granular product (kissel) based on whey and Aronia melanocarpa has been developed. The stability of kissel in three temperature modes was studied: 1st (21 ± 1)°C; 2nd with a low plus temperature (5 ± 1)°C; the 3rd with the increased (39 ± 1)°C at 80% ambient humidity. At the end of a year-long study at temperature conditions (21 ± 1)°С and (5 ± 1)°С, no changes in the organoleptic characteristics of the product were observed. Dissolution rate of the product under storage temperature conditions (21 ± 1)°C and (5 ± 1)°C did not change for 9 months. It is established that when stored at low positive temperatures 4–6°C. With and at room temperature (21 ± 1)°C. At the end of 6 months of storage, the food concentrate under study did not change its properties in terms of quality. The product testing period was 2 times longer than the specified storage period. The test results were the basis for the development of technical documentation for the production of instant granulated fruit and berry kissel.

scholarly journals Effects of heat treatment and storage temperature on the use of açaí drink by nutraceutical and beverage industries

2012 ◽  
Vol 32 (1) ◽  
pp. 9-14 ◽  
Author(s):  
Tatiane Regina Albarici ◽  
José Dalton Cruz Pessoa
Keyword(s):  
Temperature Effect ◽  
Storage Temperature ◽  
Life Time ◽  
Reaction Rate Constant ◽  
Anthocyanin Content ◽  
Order Kinetic ◽  
First Order ◽  
The Stability ◽  
And Storage ◽  
Anthocyanin Degradation

This study assesses the storage temperature effect on the anthocyanins of pasteurized and unpasteurized açaí pulp. The data was obtained using a pasteurized and lyophilized pulp (PLP) to evaluate the temperature effect (0, 25, and 40 °C). Part of non-pasteurized frozen pulp (NPP) was pasteurized (NPP-P) at 90 °C for 30 seconds; both pulps were stored at 40 °C. The anthocyanin content reduction in the drink was evaluated from the half-life time (t1/2), activation energy (Ea), temperature quotient (Q10), and the reaction rate constant (k). The t1/2 of the PLP anthocyanins stored at 40 °C was 1.8 times less than that stored at 25 °C and 15 times less than that stored at 0 °C; therefore, the higher temperatures decreased the stability of anthocyanins. The pasteurization increased the t1/2 by 6.6 times (10.14 hours for NPP and 67.28 hours for NPP-P). The anthocyanin degradation on NPP-P followed a first order kinetic, while NPP followed a second order kinetic; thus it can be said that the pasteurization process can improve the preservation of anthocyanins in the pulp.

scholarly journals Shelf Life Studies of Three Wasabi Flavoured Sauces

1970 ◽  
Vol 44 (2) ◽  
pp. 147-156
Author(s):  
Tamanna Sultana ◽  
GP Savage ◽  
NG Porter ◽  
DL McNeil ◽  
JR Sedcole
Keyword(s):  
Shelf Life ◽  
Storage Temperature ◽  
Initial Level ◽  
Tomato Sauce ◽  
Wasabia Japonica ◽  
Different Temperatures ◽  
Small Change ◽  
Shelf Life Studies ◽  
The Stability ◽  
Storage Temperatures

Isothiocyanates (ITCs) contained in purees extracted from wasabi (Wasabia japonica (Miq) Matsum) can be used to manufacture a range of interesting spicy foods. In New Zealand, local manufacturers are showing interest in producing various forms of processed wasabi based sauces. However, isothiocyanates have been shown to degrade quickly in some situations. Therefore, in this study, the stability of allyl ITC was investigated in three wasabi flavoured products stored at four different temperatures (4, 10, 20 and 30°C) for 22 weeks. Two creamy (mayonnaise and tartare) sauces and a non-creamy sauce were prepared from an original recipe and flavoured with a known volume of "wasabi oil". Two types of pouches (clear and metallic plastic) were used to store each product and allyl ITC content was measured in the stored sauces at two week intervals. The initial level of allyl ITC found in mayonnaise, tartare and smoky tomato sauces were 415.3, 411.4 and 144.7 mg/ kg respectively, prior to storage. Temperature showed a strong influence in reducing allyl ITC (P=0.005 to <0.001) but no significant effect was identified for the two types of packets used. The non-creamy smoky tomato sauce was very unstable at 10°C or higher temperatures and the allyl ITC contents reduced rapidly with increasing storage temperatures. For instance, at 30°C, a 66% loss occurred by week 2 and a 90% loss occurred by week 6 in the smoky tomato sauce. However, mayonnaise and tartare sauces had a shelf life of 8 to 9 weeks with only a marginal reduction in allyl ITC (2% overall) at all the stored temperatures (4-30°C). These creamy sauces were characterized by a sudden fall in 10 weeks ending in a 69-70% loss of allyl ITC at 22 weeks. No microbial growth occurred in any of the sauces stored at any of the temperatures during the course of this storage experiment though very small change of colour was noticed for the sauces when stored at 30°C. Keywords: Bangladesh J. Sci. Ind. Res. 44(2), 147-156, 2009DOI: 10.3329/bjsir.v44i2.3665Bangladesh J. Sci. Ind. Res. 44(2), 147-156, 2009

Stability of Enterocin AS-48 in Fruit and Vegetable Juices

2005 ◽  
Vol 68 (10) ◽  
pp. 2085-2094 ◽  
Author(s):  
MARIA J. GRANDE ◽  
ROSARIO LUCAS ◽  
EVA VALDIVIA ◽  
HIKMATE ABRIOUEL ◽  
MERCEDES MAQUEDA ◽  
...  
Keyword(s):  
Storage Temperature ◽  
Fruit Juices ◽  
Initial Activity ◽  
Fruit And Vegetable ◽  
Bacteriocin Activity ◽  
Green Beans ◽  
Food Components ◽  
Fruit And Vegetable Juices ◽  
The Stability ◽  
Thickening Agents

Enterocin AS-48 is a candidate bacteriocin for food biopreservation. Before addressing application of AS-48 to vegetable-based foods, the interaction between AS-48 and vegetable food components and the stability of AS-48 were studied. Enterocin AS-48 had variable interactions with fruit and vegetable juices, with complete, partial, or negligible loss of activity. For some juices, loss of activity was ameliorated by increasing the bacteriocin concentration, diluting the juice, or applying a heat pretreatment. In juices obtained from cabbage, cauliflower, lettuce, green beans, celery, and avocado, AS-48 was very stable for the first 24 to 48 h of storage under refrigeration, and decay of activity was markedly influenced by storage temperature. In fresh-made fruit juices (orange, apple, grapefruit, pear, pineapple, and kiwi) and juice mixtures, AS-48 was very stable for at least 15 days at 4°C, and bacteriocin activity was still detectable after 30 days of storage. Gradual and variable loss of activity occurred in juices stored at 15 and 28°C; inactivation was faster at higher temperatures. In commercial fruit juices (orange, apple, peach, and pineapple) stored at 4°C, the bacteriocin was completely stable for up to 120 days, and over 60% of initial activity was still present in juices stored at 15°C for the same period. Commercial fruit juices stored at 28°C for 120 days retained between 31.5% (apple) and 67.71% (peach) of their initial bacteriocin activity. Solutions of AS-48 in sterile distilled water were stable (120 days at 4 to 28°C). Limited loss of activity was observed after mixing AS-48 with some food-grade dyes and thickening agents. Enterocin AS-48 added to lettuce juice incubated at 15°C reduced viable counts of Listeria monocytogenes CECT 4032 and Bacillus cereus LWL1 to below detection limits and markedly reduced viable counts of Staphylococcus aureus CECT 976.

scholarly journals Multiplex PCR for direct identification of Campylobacter spp. in human and chicken stools

2007 ◽  
Vol 56 (10) ◽  
pp. 1350-1355 ◽  
Author(s):  
Aisha Al Amri ◽  
Abiola C. Senok ◽  
Abdulrahman Yusuf Ismaeel ◽  
Ali E. Al-Mahmeed ◽  
Giuseppe A. Botta
Keyword(s):  
Multiplex Pcr ◽  
Direct Detection ◽  
False Negative ◽  
Enteric Bacteria ◽  
Enzymic Activity ◽  
Campylobacter Coli ◽  
Biochemical Tests ◽  
Direct Evaluation ◽  
Stool Specimens ◽  
Culture Negative

Differentiation between Campylobacter jejuni and Campylobacter coli is problematic in clinical specimens due to fastidious growth requirements and limited biochemical tests. This study describes a rapid, multiplex PCR protocol for the direct detection and differentiation of C. jejuni and C. coli in stools. An evaluation was carried out of this multiplex protocol based on the detection of cadF (genus specific), and hipO (C. jejuni) and asp (C. coli) genes, using stool from patients with Campylobacter enteritis and chicken. Protocol sensitivity was assessed and specificity determined using a panel of enteric bacteria, and evaluation of 30 diarrhoeic stool specimens culture negative for Campylobacter. Of the 114 specimens (54 human and 60 chicken) evaluated by the protocol, 70 (61.4 %) were identified as C. jejuni, 35 (30.7 %) as C. coli and 9 (7.9 %) as a mixed infection/colonization with both species. All mixed infections were identified as C. jejuni by culture. Among the stool specimens that were culture negative for Campylobacter, two (6.7 %) were C. jejuni positive by multiplex PCR. The protocol sensitivity limit was 0.015–0.016 ng C. jejuni and C. coli DNA μl−1 in the specimen. There was no cross-reaction with the reference strains assessed. Comparison of hippurate test and multiplex PCR demonstrated 17 isolates with false-positive hippurate enzymic activity and 7 with false-negative activity. This rapid protocol (turnaround time 6 h) is highly sensitive and specific for direct evaluation of stool for these pathogens. It has significant application for routine clinical diagnostic and epidemiological purposes.

scholarly journals Characterization of enteric disease in children using a low-cost specimen preservation method

2021 ◽  
Author(s):  
Amanda K. Debes ◽  
Shaoming Xiao ◽  
Jie Liu ◽  
Allison Shaffer ◽  
Paul Scalzo ◽  
...  
Keyword(s):  
Filter Paper ◽  
Disease Burden ◽  
Stool Specimen ◽  
Diarrheal Disease ◽  
Vaccine Development ◽  
Low Cost ◽  
Preservation Method ◽  
Stool Specimens ◽  
Taqman Array

BACKGROUND: Diarrhea is a leading cause of death in children under five. Molecular methods exist for the rapid detection of enteric pathogens; however, the logistical costs of storing stool specimens limit applicability. We sought to demonstrate that dried filter paper specimen preservation can identify diarrheal diseases causing significant morbidity among children in resource constrained countries. METHODS: A sub-study was nested into cholera surveillance in Cameroon. Enrollment criteria included: enrollment between 8/1/16 - 10/1/18; age < 18 years; a stool specimen; ≥ three loose stools within 24hours with the presence of dehydration and/or blood. 7227 persons were enrolled, for which 2746 met enrollment criteria and 337 were included in this analysis using the enteric TaqMan Array Card. Bacterial pathogens were compared to severity of diarrhea, age and sex, among other variables. RESULTS: 107 were ETEC positive of which: 40.2% (N=43) LT-STh, 19.6% (N=21) LT-STp; and 49.5% (53) LT-only. Major CFs were present in 43.9% of ETEC-positives. 96 were positive for Shigella, of which 14 (14.6%) reported dysentery. Model-derived quantitative cutoffs identified 116 (34.4%) with one highly diarrhea-associated pathogen and 16 (4.7%) with ≥ two. Shigellae and rotavirus were most strongly associated with diarrhea in children with mixed infections. CONCLUSION: Dried filter paper preserved specimens eliminate the need for frozen stool specimens and will facilitate enteric surveillance and contribute to the understanding of disease burden, which is needed to guide vaccine development and introduction. This study confirms Rotavirus, Shigella and ETEC as major contributors to pediatric diarrheal disease in two regions of Cameroon.

scholarly journals Clostridium difficile colonization among patients with clinically significant diarrhea and no identifiable cause of diarrhea

2018 ◽  
Vol 39 (11) ◽  
pp. 1330-1333 ◽  
Author(s):  
Erik R. Dubberke ◽  
Kimberly A. Reske ◽  
Tiffany Hink ◽  
Jennie H. Kwon ◽  
Candice Cass ◽  
...  
Keyword(s):  
Clostridium Difficile ◽  
Patient Population ◽  
Tertiary Care ◽  
Clinical Microbiology Laboratory ◽  
Care Hospital ◽  
Toxigenic Culture ◽  
Stool Samples ◽  
Stool Specimens ◽  
Clinically Significant ◽  
Culture Negative

AbstractObjectiveTo determine the prevalence of Clostridium difficile colonization among patients who meet the 2017 IDSA/SHEA C. difficile infection (CDI) Clinical Guideline Update criteria for the preferred patient population for C. difficile testing.DesignRetrospective cohort.SettingTertiary-care hospital in St. Louis, Missouri.PatientsPatients whose diarrheal stool samples were submitted to the hospital’s clinical microbiology laboratory for C. difficile testing (toxin EIA) from August 2014 to September 2016.InterventionsElectronic and manual chart review were used to determine whether patients tested for C. difficile toxin had clinically significant diarrhea and/or any alternate cause for diarrhea. Toxigenic C. difficile culture was performed on all stool specimens from patients with clinically significant diarrhea and no known alternate cause for their diarrhea.ResultsA total of 8,931 patients with stool specimens submitted were evaluated: 570 stool specimens were EIA positive (+) and 8,361 stool specimens were EIA negative (−). Among the EIA+stool specimens, 107 (19% of total) were deemed eligible for culture. Among the EIA− stool specimens, 515 (6%) were eligible for culture. One EIA+stool specimen (1%) was toxigenic culture negative. Among the EIA− stool specimens that underwent culture, toxigenic C. difficile was isolated from 63 (12%).ConclusionsMost patients tested for C. difficile do not have clinically significant diarrhea and/or potential alternate causes for diarrhea. The prevalence of toxigenic C. difficile colonization among EIA− patients who met the IDSA/SHEA CDI guideline criteria for preferred patient population for C. difficile testing was 12%.

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