scholarly journals Rapid Detection of Pectolytic Erwinia sp. in Aglaonema sp.

1998 ◽  
Vol 8 (4) ◽  
pp. 602-605 ◽  
Author(s):  
R.S. Arias ◽  
A.M. Alvarez ◽  
P.K. Murakami
Keyword(s):  
Erwinia Chrysanthemi ◽  
Microplate Assay ◽  
Bacterial Strains ◽  
Pseudomonas Solanacearum ◽  
San Luis ◽  
Yellow Color ◽  
Colony Forming Units ◽  
Stems And Leaves ◽  
Low Levels ◽  
Pseudomonas Paucimobilis

The purpose of this research was to develop a rapid microplate assay for detecting and presumptively identifying pathogenic pectolytic Erwinia sp. in ornamental propagative stock and to readily distinguish them from nonpathogenic bacteria associated with Aglaonema. The assay was developed by modifying an existing crystal violet-sodium polypectate (CVP) medium to visualize the depolymerization of pectate by addition of bromcresol purple (BCP), then acidifying with a dilute hydrochloric acid (HCl) solution. The assay was sufficiently sensitive to detect latent (symptomless) infections in small sections of leaf or stem tissue. Based on inoculum titration assays, 40 to 600 colony-forming units (CFU) of Erwinia chrysanthemi (Burkholder et al.) were required to produce symptoms in Aglaonema stems and leaves, respectively. The microplate assay was able to detect the pathogen at low levels (40 to 60 CFU) in tissue segments of ≈1 cm2. In tests of bacterial strains isolated from 211 samples from Aglaonema `Silver Queen', `Emerald Beauty', and `San Luis' grown in Hawaii, only the pectolytic and pathogenic Erwinia sp. reacted positively in the microplate assay. Other bacteria associated with Aglaonema, including Pseudomonas paucimobilis (Holmes), P. vesicularis (Galarneault and Leifson), and nonpectolytic Erwinia sp., were not detected by the assay. Pectolytic strains of Ralstonia (Pseudomonas) solanacearum (Smith) were differentiated from pectolytic Erwinia sp. by the yellow color that developed in wells of the latter strains after acidification of the medium with dilute HCl. The test is visual and can be performed with minimal equipment and cost.

scholarly journals Evaluation of a Continuous Decontamination Technology in an Intensive Care Unit

2020 ◽  
Vol 41 (S1) ◽  
pp. s519-s519
Author(s):  
Tami Inman BSN ◽  
David Chansolme
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Urban Hospital ◽  
Patient Room ◽  
Colony Forming Units ◽  
Prevention Interventions ◽  
Continuous Application ◽  
Low Levels ◽  
Healthcare Associated ◽  
Cleaning And Disinfection

Background: The scientific literature increasingly indicates the need for the development of continuous disinfection to address the persistent contamination and recontamination that occurs in the patient rooms despite routine cleaning and disinfection. Methods: To determine a baseline microbial burden level on patient room surfaces in the intensive care unit (ICU) of a large urban hospital, 50 locations were swabbed for total colony-forming units (CFU) and the prevalence of methicillin-resistant Staphylococcus aureus (MRSA). Once the baseline in ICU patient rooms was established, 5 novel decontamination devices were installed in the HVAC ducts near these patient rooms. The devices provide a continuous low-level application of oxidizing molecules, predominately hydrogen peroxide. These molecules exit the duct and circulate in the patient room through normal convection, landing on all surfaces. After activation, environmental sampling was conducted every 4 weeks for 4 months. The effect from continuous low levels of oxidizing molecules on the intrinsic microbial burden and the prevalence of MRSA were analyzed. In addition to external laboratory reports, the facility tracked healthcare-associated infections (HAIs) in the unit. HAI data were averaged by month and were compared to the preactivation average in the same unit. Results: The preactivation average microbial burden found on the 50 locations were 179,000 CFU per 100 in2. The prevalence of MRSA was 71% with an average of 81 CFU per 100 in2. After activation of the devices, levels of microbial burden, prevalence of MRSA, and average monthly HAI rates were all significantly lower on average: 95% reduction in average microbial burden (8,206 CFU per 100 in2); 81% reduction in the prevalence of MRSA (13% vs 71%); 54% reduction in the average of healthcare-onset HAIs. All data were obtained from the averages of sampling data for 4 weeks during the 4-month trial period. Conclusions: The continuous application of low levels of oxidizing molecules throughout the patient rooms of an ICU demonstrated 3 outcomes: reduced overall surface microbial burden, lowered the incidence of MRSA, and significantly decreased the monthly average HAI rate. Please note, the ICU ran other infection prevention interventions at this time, including standard cleaning, as well as and their standard disinfecting techniques.Funding: This study was supported by the CASPR Group.Disclosures: None

scholarly journals Distribution of Growth-Inhibiting Bacteria against the Toxic Dinoflagellate Alexandrium catenella (Group I) in Akkeshi-Ko Estuary and Akkeshi Bay, Hokkaido, Japan

2020 ◽  
Vol 11 (1) ◽  
pp. 172
Author(s):  
Yuka Onishi ◽  
Akihiro Tuji ◽  
Atsushi Yamaguchi ◽  
Ichiro Imai
Keyword(s):  
Surface Waters ◽  
Seagrass Bed ◽  
Bacterial Strains ◽  
Toxic Dinoflagellate ◽  
Sequence Analyses ◽  
Alexandrium Catenella ◽  
Group I ◽  
Colony Forming Units ◽  
Rrna Sequences ◽  
Growth Inhibiting

The distribution of growth-inhibiting bacteria (GIB) against the toxic dinoflagellate Alexandrium catenella (Group I) was investigated targeting seagrass leaves and surface waters at the seagrass bed of Akkeshi-ko Estuary and surface waters of nearshore and offshore points of Akkeshi Bay, Japan. Weekly samplings were conducted from April to June in 2011. GIBs were detected from surface of leaves of the seagrass Zostera marina in Akkeshi-ko Estuary (7.5 × 105–4.7 × 106 colony-forming units: CFU g−1 wet leaf) and seawater at the stations in Akkeshi Bay (6.7 × 100–1.1 × 103 CFU mL−1). Sequence analyses revealed that the same bacterial strains with the same 16S rRNA sequences were isolated from the surface biofilm of Z. marina and the seawater in the Akkeshi Bay. We therefore strongly suggested that seagrass beds are the source of algicidal and growth-inhibiting bacteria in coastal ecosystems. Cells of A.catenella were not detected from seawaters in Akkeshi-ko Estuary and the coastal point of Akkeshi Bay, but frequently detected at the offshore point of Akkeshi Bay. It is suggested that A.catenella populations were suppressed by abundant GIBs derived from the seagrass bed, leading to the less toxin contamination of bivalves in Akkeshi-ko Estuary.

Microbiological Quality of Commercial Tofu

1984 ◽  
Vol 47 (3) ◽  
pp. 177-181 ◽  
Author(s):  
T. G. REHBERGER ◽  
L. A. WILSON ◽  
B. A. GLATZ
Keyword(s):  
Microbiological Quality ◽  
Plate Count ◽  
Microbial Counts ◽  
Colony Forming Units ◽  
Low Levels ◽  
Microbial Groups ◽  
Yeasts And Molds ◽  
Processing Techniques

A study was done to investigate the microbiological quality of commercial tofu available in local retail outlets. A sampling method was first developed to obtain accurate and representative microbial counts of individual pieces of tofu. Plate count determination of total aerobic organisms, psychrotrophs, coliforms, sporeformers, yeasts and molds, and staphylococci were made on 60 tofu samples (representing three lots each of four different brands) obtained within 24 h after delivery to the retail store. In addition, for two brands that provided manufacturer's pull dates, the same microbial counts were obtained for samples stored in the laboratory at 10°C until the pull date. Of the tofu sampled immediately after purchase, 83% of the lots tested had total counts greater than 106 colony-forming units (CFU)/g and psychrotrophic counts greater than 104 CFU/g. In addition, 67% of the lots tested had confirmed coliform counts greater than 103 CFU/g. Very low levels (less than 10 CFU/g) of all other microbial groups tested for were found in the majority of lots. Samples held until the manufacturer's pull date contained higher total and psychrotrophic counts but lower or stable counts of other organisms compared with samples tested immediately after purchase. To improve the microbiological quality of tofu, processors need to reduce initial loads by improving sanitation and processing techniques, and retailers should provide more consistent and colder refrigerated storage.

scholarly journals Chemical Constituents of Stems and Leaves of Tagetespatula L. and Its Fingerprint

Molecules ◽  
2019 ◽  
Vol 24 (21) ◽  
pp. 3911 ◽  
Author(s):  
Yu-Meng Wang ◽  
Xiao-Ku Ran ◽  
Muhammad Riaz ◽  
Miao Yu ◽  
Qian Cai ◽  
...  
Keyword(s):  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
Chemical Constituents ◽  
Human Gastric Cancer ◽  
Chemical Structures ◽  
Yellow Color ◽  
Ic50 Values ◽  
Gastric Cancer Cell Lines ◽  
Stems And Leaves

Tagetespatula L. is a widely cultivated herbal medicinal plant in China and other countries. In this study, two new 2, 3-dihydrobenzofuran glucosides (1, 2) and fourteen known metabolites (3–16) were isolated from the stems and leaves of T. patula (SLT). The chemical structures of the isolated compounds were characterized comprehensively based on one- and two-dimensional NMR spectroscopy and high resolution mass spectrometry. Absolute configurations of compounds 1 and 2 were determined by ECD calculations. Compounds 1 and 2 exhibited moderate in vitro inhibitory activities against human gastric cancer cell lines (AGS) with IC50 values of 41.20 μmol/L and 30.43 μmol/L, respectively. The fingerprint profiles of stems and leaves of T. patula with three color types of flowers (Janie Yellow Bright, Jinmen Orange, Shouyao Red and Yellow color) were established by high-performance liquid chromatography (HPLC). Ten different batches of stems and leaves were examined as follow: Shouyao Red and Yellow color (1, 2, 3), Janie Yellow Bright (4, 5, 6, 7) and Jinmen Orange (8, 9, 10). Twenty-two common peaks were identified with similarity values ranging from 0.910 to 0.977. Meanwhile, the average peak area of SLT in the three types of flowers was different and it was the highest in Janie Yellow Bright.

scholarly journals Chemical Composition and Antibacterial Activity of Essential oil from Salvia mukerjeei

2011 ◽  
Vol 6 (12) ◽  
pp. 1934578X1100601 ◽  
Author(s):  
Lalit Mohan ◽  
Anuradha Negi ◽  
Anand B. Melkani ◽  
Vasu Dev
Keyword(s):  
Antibacterial Activity ◽  
Chemical Composition ◽  
Agrobacterium Tumefaciens ◽  
Essential Oil ◽  
Volatile Oil ◽  
Erwinia Chrysanthemi ◽  
Bacterial Strains ◽  
Capillary Gc ◽  
Aerial Parts ◽  
Sesquiterpene Hydrocarbons

The composition of steam volatile oil from aerial parts of Salvia mukerjeei Bennet & Raizada (Lamiaceae) was analyzed by capillary GC and GCMS. The oil was rich in sesquiterpene hydrocarbons (67.3%). Among 71 identified constituents representing 91.7% of the oil, β-caryophyllene (28.7%), γ-muurolene (15.5%) and dehydro-aromadendrane (9.5%), were the principal constituents. The oil was tested against ten bacterial strains and was active against Enterococcus faecalis, Erwinia chrysanthemi and Agrobacterium tumefaciens.

Carbapenem-Resistant Enterobacteriaceae: Frequency of Hospital Room Contamination and Survival on Various Inoculated Surfaces

2015 ◽  
Vol 36 (5) ◽  
pp. 590-593 ◽  
Author(s):  
David J. Weber ◽  
William A. Rutala ◽  
Hajime Kanamori ◽  
Maria F. Gergen ◽  
Emily E. Sickbert-Bennett
Keyword(s):  
Infect Control Hosp ◽  
Hospital Room ◽  
Carbapenem Resistant ◽  
Environmental Surfaces ◽  
Colony Forming Units ◽  
Low Levels ◽  
Carbapenem Resistant Enterobacteriaceae

Carbapenem-resistant Enterobacteriaceae (CRE) only contaminated the environmental surfaces of rooms housing CRE colonized/infected patients infrequently (8.4%) and at low levels (average, 5.1 colony-forming units [CFU]/120 cm2 per contaminated surface). Three species of CRE (Klebsiella, Enterobacter, and Escherichia) survived poorly (>85% die-off in 24 hours) when ~2 log10 CFU were inoculated onto 5 different environmental surfaces.Infect Control Hosp Epidemiol 2015;00(0): 1–4

scholarly journals Melanin-Based High-Throughput Screen for l-Tyrosine Production in Escherichia coli

2007 ◽  
Vol 74 (4) ◽  
pp. 1190-1197 ◽  
Author(s):  
Christine Nicole S. Santos ◽  
Gregory Stephanopoulos
Keyword(s):  
Escherichia Coli ◽  
High Throughput ◽  
Combinatorial Libraries ◽  
Selection Strategy ◽  
High Throughput Screen ◽  
Bacterial Strains ◽  
Gene Encoding ◽  
Strong Linear Correlation ◽  
Low Levels ◽  
Tyrosine Content

ABSTRACT We present the development of a simple, high-throughput screen for identifying bacterial strains capable of l-tyrosine production. Through the introduction of a heterologous gene encoding a tyrosinase, we were able to link l-tyrosine production in Escherichia coli with the synthesis of the black and diffusible pigment melanin. Although melanin was initially produced only at low levels in morpholinepropanesulfonic acid (MOPS) minimal medium, phosphate supplementation was found to be sufficient for increasing both the rates of synthesis and the final titers of melanin. Furthermore, a strong linear correlation between extracellular l-tyrosine content and melanin formation was observed by use of this new medium formulation. A selection strategy that utilizes these findings has been developed and has been shown to be effective in screening large combinatorial libraries in the search for l-tyrosine-overproducing strains.

scholarly journals Evaluation of the disinfecting capacity of ozone in emergency vehicles

2020 ◽  
Author(s):  
Jorge Biurrun Cía ◽  
Begoña García Martínez ◽  
Andrea Perez Montero ◽  
Grazyna Kochan ◽  
David Escors ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Lentiviral Vector ◽  
Ozone Treatment ◽  
Bacterial Strains ◽  
Health Crisis ◽  
Colony Forming Units ◽  
Objective Evidence ◽  
Emergency Vehicles ◽  
Viable Bacteria ◽  
Pre Treatment

ABSTRACTObjectiveAs a consequence of the health crisis arising from the SARS-CoV-2 coronavirus pandemic, ozone treatments are being applied as disinfectant in emergency vehicles, without objective evidence on its efficacy. Here we evaluate the efficacy of ozone treatment over bacterial strains and virus-like particles.MethodA preparation of a lentiviral vector (lentivector) and dried cultures of two bacterial strains (gram + Staphylococcus aureus and gram - Salmonella enterica ser. Enteritidis) were placed inside an ambulance at two different locations. The interior of the vehicle was subjected to 10 min and 20 min treatments (3 and 6 times the recommended time by the manufacturer). Following the treatments, lentivector preparations were titrated, and viable bacteria (colony forming units, CFUs) counted and compared to pre-treatment titers and infectious CFUs of the same lysates and cultures.ResultsNone of the treatments significantly reduced either lentivector titer or the number of viable bacteria.ConclusionsAt least in the analyzed conditions and for the microorganisms used in this study, it can be concluded that ozone treatment is not advisable for the disinfection of emergency vehicles.

scholarly journals Screening of Ranunculus sceleratus for enzyme inhibition, antibacterial and antioxidant activities

2015 ◽  
Vol 10 (2) ◽  
pp. 436 ◽  
Author(s):  
Sammia Shahid ◽  
Tauheeda Riaz ◽  
Muhammad Nadeem Asghar
Keyword(s):  
Ethyl Acetate ◽  
Enzyme Inhibition ◽  
Soluble Fraction ◽  
Antioxidant Activities ◽  
Good Activity ◽  
Degenerative Diseases ◽  
Microplate Assay ◽  
Dpph Radical ◽  
Bacterial Strains ◽  
Excellent Activity

<p>Enzyme inhibition potential of various fractions of <em>Ranunculus sceleratus</em> was checked against α-glucosidase, butyrylcholinesterase, acetylcholinesterase and lipoxygenase enzymes. n-Butanol fraction showed very good activity (77.5 ± 1.0% inhibition at 0.1 mg/mL) against α-glucosidase. Its IC<sub>50</sub> value was 35.7 ± 1.0 µg/mL comparable to quercetin (IC<sub>50</sub> value 16.5 ± 0.4 µg/mL). Antibacterial activity was checked against five bacterial strains by 96-wells microplate assay using ciprofloxacin, a standard antibiotic. Chloroform, ethyl acetate, n-butanol and aqueous fractions showed excellent activity against <em>Pseudomonas aeruginosa</em>, (MIC at 7.1, 7.8, 5.6 and 5.3 respectively), which is greater than standard antibiotic ciprofloxacin (MIC 10.0). The antioxidant potential of all the fractions was evaluated. Ethyl acetate soluble fraction exhibited highest percent inhibition of DPPH radical as compared to other fractions. It showed 80.9 ± 1.2% inhibition of DPPH radical at a concentration of 30 µg/mL. These results suggest that <em>R. sceleratus</em> is a valuable herb, which inhibits the oxidative stress mechanism that lead to degenerative diseases.  </p><p> </p>

scholarly journals Rapid Determination of Listeria monocytogenes by Automated Enzyme-Linked Immunoassay and Nonradioactive DNA Probe

2000 ◽  
Vol 83 (1) ◽  
pp. 86-88 ◽  
Author(s):  
Khalil F Kerdahi ◽  
Philip F Istafanos
Keyword(s):  
Listeria Monocytogenes ◽  
Rapid Determination ◽  
Food Samples ◽  
Dna Probe ◽  
Negative Results ◽  
Smoked Salmon ◽  
Colony Forming Units ◽  
Low Levels ◽  
Analytical Time

Abstract A rapid and reliable analytical method was developed to detect and confirm the presence of Listeria monocytogenes in raw and partially processed foods. Forty-nine food samples (25 mixed cut vegetable salad, 12 smoked salmon, and 12 sterile smoked salmon) were individually inoculated with high levels [10–100 colony forming units (cfu)/25 g sample] and low levels (1–10 cfu/25 g sample) of L. monocytogenes, and were screened using the Vitek Immuno Diagnostic Assay (VIDAS) Listeria monocytogenes (VIDAS LMO)]. Positive test results were confirmed as L. monocytogenes by nonradioactive DNA probe. All samples inoculated with high levels of L. monocytogenes were detected by VIDAS and 96% were confirmed as L. monocytogenes by DNA probe. VIDAS LMO detected 89% of samples inoculated with low levels of L. monocytogenes, and 87% of these were confirmed as positive by DNA probe. In addition, 12 other samples (4 from each of mixed cut vegetable salad, smoked salmon, and sterile smoked salmon) were inoculated with high levels of L. ivanovii, L. seeligeri, L. welshimeri, L. innocua, L. grayi, and L. murrayi. Samples were assayed by the same protocol and all gave negative results. Compared with the cultural method, the VIDAS LMO nonradioactive DNA probe combination is highly specific, discriminates between L. monocytogenes and all other Listeria species, and reduces analytical time.

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