scholarly journals The effect of disinfectants on fungi in pure culture and on different surface materials

1992 ◽  
Vol 1 (6) ◽  
pp. 587-596
Author(s):  
Hilkka Koponen ◽  
Hanna Avikainen ◽  
Risto Tahvonen
Keyword(s):  
Rhizoctonia Solani ◽  
Verticillium Dahliae ◽  
Pure Culture ◽  
Treatment Time ◽  
The Other ◽  
Fusarium Avenaceum ◽  
Pure Cultures ◽  
Phoma Foveata ◽  
Plastic Surfaces ◽  
Wood Surfaces

The effect of eight disinfectants was tested on 11 fungi. The concentrations recommended by the manufacturers were mostly used in the present trials. Five and 15 min treatment times were too short for most preparations. The best efficacy was achieved at 60 min treatment lime. In pure cultures, all disinfectants tested were most effective against Pythium sp. Overall, the most effective preparation was Desinfektol EL which was effective against all fungi tested at 5 min treatment time. Wood surfaces were more difficult to disinfest than metal and plastic surfaces. Rhizoctonia solani and Verticillium dahliae were highly susceptible only to Desinfektol EL, and NaOCl controlled Pythium sp. and Botrytis cinerea. None of the preparations controlled completely the other test fungi. On metal surfaces the most effective disinfectants were Desinfektol EL and NaOCl; moderately effective were lobac P and Menno-Ter-forte. Korsolin was the least effective preparation. Verticillium dahliae and Phomopsis sderotioides were difficult to kill. The easiest fungi to disinfest were Pythium sp., Rhizoctonia solani, B. cinerea, Fusarium avenaceum, F. culmorum, F. oxysporum, Mycocentrospora acerina and Phoma foveata. Fungi grown on plastic surfaces were best controlled with Desinfektol EL. Also NaOCl, Menno-Ter-forte and lobac P were effective. Korsolin was the least effective preparation. The easiest fungi to eradicate were Pythium sp. and R. solani. The most difficult fungi were V. dahliae and P. sderotioides. Both peat and clay deteriorated the efficacy of the disinfectants except for Desinfektol EL.

Biodegradation of chlorophenols by immobilized pure-culture microorganisms

1996 ◽  
Vol 34 (10) ◽  
pp. 67-72 ◽  
Author(s):  
Lu Chih-Jen ◽  
Lee Chi-Mei ◽  
Huang Chiou-Zong
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Pseudomonas Putida ◽  
Pure Culture ◽  
The Other ◽  
Batch Reactors ◽  
Agrobacterium Radiobacter ◽  
Culture Cells ◽  
Lag Period

The biodegradation of phenol and chlorophenols by immobilized pure-culture cells was conducted by a series of batch reactors. The microorganisms used in this study were Pseudomonas putida, Psuedomonas testosteroni, Pseudomonas aeruginosa, and Agrobacterium radiobacter. All four species showed the ortho-cleavage pathway to metabolize chlorophenols. Among the four species, P. testosteroni, P. putida, and P. aeruginosa could effectively remove phenol at 200 mg/l. P. testosteroni could effectively remove 2-chlorophenol at 10mg/l. However, the other three species, P. putida, P. aeruginosa, and A. radiobacter, could not effectively remove 2-chlorophenol. Although 3-chlorophenol is a recalcitrant compound, P. testosteroni also could rapidly metabolize 3-chlorophenol at 10 mg/l. The removal of 4-chlorophenol at 10 mg/l by P. testosteroni reached 98% within one day. P. aeruginosa and A. radiobacter also could metabolize 4-chlorophenol after 2 and 7 days of lag period, respectively.

scholarly journals PSV-7 Effects of drying and oxygenation of piglets at birth on rectal temperatures in the early post-natal period

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 154-155
Author(s):  
Katherine Vande Pol ◽  
Naomi Cooper ◽  
Andres Tolosa ◽  
Michael Ellis ◽  
Richard Gates ◽  
...  
Keyword(s):  
Statistical Model ◽  
Birth Control ◽  
Rectal Temperature ◽  
Treatment Time ◽  
The Other ◽  
Experimental Unit ◽  
Potential Treatment ◽  
Temperature Changes ◽  
Oxygen Treatment ◽  
Birth Data

Abstract Piglets often experience hypothermia early after birth. Previous research has suggested that drying piglets and administration of oxygen (a potential treatment for asphyxiation) at birth may increase post-natal rectal temperatures. The objective of this study was to determine the effects of drying and administering oxygen at birth on piglet rectal temperature over the first 24 h after birth. The study, conducted at a commercial facility, used a CRD with 42 sows/litters randomly allotted at start of farrowing to 3 treatments (applied at birth): Control (no drying or oxygenation); Dried (using a cellulose-based desiccant); Dried+Oxygen [dried and placed in a chamber (40% oxygen) for 20 min]. At birth, piglets were weighed and uniquely identified. Rectal temperature was measured at 0, 20, 30, 45, 60, 120, and 1440 min after birth. Data were analyzed using PROC MIXED of SAS. Litter was the experimental unit; piglet was a subsample of litter. The statistical model included effects of treatment, time of measurement, and the interaction. Both the Dried and Dried+Oxygen treatments had greater (P < 0.05) rectal temperatures than the Control between 20 and 120 min. However, the Dried+Oxygen treatment had lower (P < 0.05) rectal temperatures than the Dried treatment between 20 and 60 minutes. Temperatures at 1440 min were lower (P < 0.05) for the Dried+Oxygen than the other treatments; however, differences were small. In conclusion, drying piglets at birth increased rectal temperatures over the first 2 h after birth. The combination of drying piglets at birth and placement in an oxygen chamber for 20 min was less effective at moderating post-natal temperature changes than drying alone. Further research on piglet oxygenation is necessary to understand the reason for these reduced temperatures, and whether this treatment affects pre-weaning mortality. This research was funded by the National Pork Board.

Development and quantitative measurement of microsclerotia of Verticillium dahliae

1972 ◽  
Vol 50 (11) ◽  
pp. 2097-2102 ◽  
Author(s):  
R. Hall ◽  
H. Ly
Keyword(s):  
Verticillium Dahliae ◽  
Mycelial Growth ◽  
Quantitative Measurement ◽  
Dry Weight ◽  
Pure Cultures ◽  
Carbon Nitrogen Ratio ◽  
Low Glucose ◽  
Nitrogen Ratio ◽  
Total Dry Weight ◽  
Hyaline Material

The development of microsclerotia of Verticillium dahliae from a few swollen hyaline cells on a hypha to a multicellular, pigmented "mature" structure is described and illustrated. A method for quantitatively estimating the amount of pigmented microsclerotial material in pure cultures was developed to study quantitative relations between mycelial growth and production of microsclerotial material in media containing different concentrations of glucose. At low glucose concentrations (0.6 to 10 mg/ml) microsclerotial material continued to increase after total dry weight of the cultures had reached a maximum, suggesting conversion of hyaline to pigmented material. At high glucose concentrations (20 to 60 mg/ml) the patterns of increase in total dry weight, microsclerotial material, and hyaline material were similar over a 4-week incubation period. Maximum production of both pigmented and hyaline materials occurred at a glucose concentration of 30 mg/ml (carbon/nitrogen ratio of 50/1).

Prognostic Factors in Early Glottic Carcinoma Implications for Treatment

2005 ◽  
Vol 91 (2) ◽  
pp. 182-187 ◽  
Author(s):  
Demiral Ayse Nur ◽  
Cetinayak Oguz ◽  
Erdag Taner Kemal ◽  
Eyiler Ferhat ◽  
Sarıoglu Sülen ◽  
...  
Keyword(s):  
Prognostic Factors ◽  
Treatment Time ◽  
Salvage Surgery ◽  
Anterior Commissure ◽  
The Other ◽  
Second Primary ◽  
Partial Laryngectomy ◽  
Glottic Carcinoma ◽  
T Classification ◽  
Early Glottic Carcinoma

Aim In this study we aimed to determine the prognostic factors affecting local control (LC) in limited glottic carcinoma treated with definitive radiotherapy (RT). Material and methods Between June 1991 and December 2001, 114 patients with early squamous-cell carcinoma of the glottis were treated with definitive RT at our institution. Only four (3.5%) patients were women. The median age was 60 (27-79). Fifteen percent, 72% and 13% of the patients had Tis, T1 and T2 tumors, respectively. Forty-three (37.7%) patients had anterior commissure invasion. Prior to RT 35 (31%) patients had undergone vocal cord stripping and two (2%) cordectomy. A median dose of 66 Gy (50-70.2) was given over a median period of 46 days (20-60). Univariate and multivariate analyses were performed for LC. The prognostic parameters analyzed for LC were T classification, anterior commissure involvement, total RT dose, and overall treatment time. Results Five-year local and regional control rates were 84.2% and 97.7%. RTOG grade 3-4 late side effects were observed only in one (0.9%) patient. In 15 patients with local failure, salvage treatment consisted of partial laryngectomy in eight patients and total laryngectomy in five. One of the remaining two patients was medically inoperable, and the other refused salvage surgery. In one of the three patients with regional failure, salvage surgery was applied and the other two were given palliative chemotherapy because of unresectable disease. Following salvage treatments, the ultimate five-year LC rate was 96.9% and the five-year larynx preservation rate was 91.1%. Second primary cancer was diagnosed in 17 (14.9%) patients. Only one patient developed distant metastases and two patients died of laryngeal cancer. While T2 disease and anterior commissure involvement were found to be unfavorable prognostic factors significantly influencing LC in univariate analyses, only T2 disease remained independent in multivariate analysis. Conclusion In patients with early glottic carcinoma, T classification proved to be the only independent prognostic factor affecting LC after primary radiotherapy according to the results of this study.

Species interactions in mixed-community crystalline biofilms on urinary catheters

2007 ◽  
Vol 56 (11) ◽  
pp. 1549-1557 ◽  
Author(s):  
Sarah M. Macleod ◽  
David J. Stickler
Keyword(s):  
Urinary Tract ◽  
Species Interactions ◽  
The Other ◽  
Experimental Investigations ◽  
Crystal Formation ◽  
Urinary Catheters ◽  
E Coli ◽  
Pure Cultures ◽  
Providencia Stuartii

Previous experimental investigations of the crystalline biofilms that colonize and block urinary catheters have focussed on their formation by pure cultures of Proteus mirabilis. In the urine of patients undergoing long-term catheterization, P. mirabilis is commonly found in mixed communities with other urinary tract pathogens. Little is known about the effect that the other species have on the rate at which P. mirabilis encrusts catheters. In the present study, a set of data on the nature of the bacterial communities on 106 catheter biofilms has been analysed and it was found that while species such as Providencia stuartii and Klebsiella pneumoniae were commonly associated with P. mirabilis, when Escherichia coli, Morganella morganii or Enterobacter cloacae were present, P. mirabilis was rarely or never found. The hypothesis that the absence of P. mirabilis from some biofilm communities could be due to its active exclusion by other species has also been examined. Experiments in laboratory models showed that co-infection of P. mirabilis with M. morganii, K. pneumoniae or E. coli had no effect on the ability of P. mirabilis to encrust and block catheters. Co-infection with Ent. cloacae or Pseudomonas aeruginosa, however, significantly increased the time that catheters took to block (P <0.05). The growth of Ent. cloacae, M. morganii, K. pneumoniae or E. coli in the model for 72 h prior to superinfection with P. mirabilis significantly delayed catheter blockage. In the case of Ent. cloacae, for example, the mean time to blockage was extended from 28.7 h to 60.7 h (P ≤0.01). In all cases, however, P. mirabilis was able to generate alkaline urine, colonize the biofilms, induce crystal formation and block the catheters. The results suggest that although there is a degree of antagonism between P. mirabilis and some of the other urinary tract organisms, the effects are temporary and whatever the pre-existing urinary microbiota, infection with P. mirabilis is thus likely to lead to catheter encrustation and blockage.

scholarly journals Interlaboratory Comparison of Methods To Quantify Microsclerotia of Verticillium dahliae in Soil

1998 ◽  
Vol 64 (10) ◽  
pp. 3846-3853 ◽  
Author(s):  
A. J. Termorshuizen ◽  
J. R. Davis ◽  
G. Gort ◽  
D. C. Harris ◽  
O. C. Huisman ◽  
...  
Keyword(s):  
Verticillium Dahliae ◽  
Interlaboratory Comparison ◽  
Petri Dish ◽  
Soil Samples ◽  
The Other ◽  
Comparison Of Methods ◽  
Research Groups ◽  
Soil Suspension ◽  
Blinded Fashion ◽  
Dry Soil

ABSTRACT In a comparison of different methods for estimatingVerticillium dahliae in soil, 14 soil samples were analyzed in a blinded fashion by 13 research groups in seven countries, using their preferred methods. One group analyzed only four samples. Twelve soil samples were naturally infested, and two had known numbers of microsclerotia of V. dahliae added to them. In addition, a control was included to determine whether transport had an effect on the results. Results differed considerably among the research groups. There was a 118-fold difference between the groups with the lowest and highest mean estimates. Results of the other groups were evenly distributed between these extremes. In general, methods based on plating dry soil samples gave higher numbers of V. dahliae than did plating of an aqueous soil suspension. Recovery of V. dahliae from samples with added microsclerotia varied from 0 to 59%. Most of the variability within each analysis was at the petri dish level. The results indicate the necessity to check the performance of detection assays regularly by comparing recoveries with other laboratories, using a common set of soil samples. We conclude that wet plating assays are less accurate than dry plating assays.

Development of breathable Janus superhydrophobic polyester fabrics using alkaline hydrolysis and blade coating

2018 ◽  
Vol 89 (6) ◽  
pp. 959-974 ◽  
Author(s):  
Seonyoung Youn ◽  
Chung Hee Park
Keyword(s):  
Mechanical Properties ◽  
Alkaline Hydrolysis ◽  
Structural Changes ◽  
Treatment Time ◽  
Volume Ratio ◽  
Alkaline Treatment ◽  
The Other ◽  
Solution Temperature ◽  
Optimal Conditions ◽  
Wetting Properties

Alkaline hydrolysis is a common finishing method that is used to give polyester (polyethylene terephthalate, PET) a more natural touch and improved luster via chemical or physical changes in the fibers. However, its potential as a tool for surface modification in the development of single-sided superhydrophobic materials has not been studied yet. In this research, Janus superhydrophobic PET fabrics with asymmetric wetting properties (one side of the PET surface was rendered superhydrophobic while the other side was simply hydrophobic) were fabricated in two steps. Fine roughness was first achieved on the surface of PET fabrics by alkaline hydrolysis. Subsequently, optimized foam-coating emulsions were applied on only one surface of the alkaline-hydrolyzed PET. Alkaline treatment time, solution temperature, and viscosity of the foam-coating emulsions were varied to find optimal conditions in terms of structural changes, mechanical properties, superhydrophobicity, and absorption ability. The specimen treated with an aqueous solution of 8% sodium hydroxide at 70℃ for 60 min and coated with the mixture of the fluoro-emulsion and thickener in the volume ratio of 40:2 was determined to be the optimal conditions for the Janus superhydrophobic property. This sample showed a contact angle of 162.8° and a shedding angle of 5.6° on one side, whereas it completely permitted the percolation of water drops on the other side within 109 s. The mechanical properties of the developed Janus PET under the optimal conditions did not decrease significantly; its weight and tensile strength were found to have decreased by 3.3% and 19.2%, respectively. Furthermore, the single-sided superhydrophobic specimen demonstrated higher moisture transmissibility than the double-sided coated PET under the same alkaline treatment conditions. The method developed herein eliminates the requirement for an additional process to deliver nanoscale surface roughness and has the potential to produce waterproof–breathable PET fabrics for outdoor clothing.

Effect of Enrichment Media and Sampling Protocol on Recovery of Listeria monocytogenes

1990 ◽  
Vol 53 (6) ◽  
pp. 505-507 ◽  
Author(s):  
J. S. BAILEY ◽  
D. L. FLETCHER ◽  
N. A. COX
Keyword(s):  
Listeria Monocytogenes ◽  
Pure Culture ◽  
Sampling Protocol ◽  
Enrichment Broth ◽  
Secondary Enrichment ◽  
Pure Cultures ◽  
University Of Vermont

These studies examined the differences in recovery of Listeria monocytogenes from pure culture and in the populations of mixed aerobic microflora from chicken and Brie cheese incubated in University of Vermont (UVM) and Listeria enrichment broth (LEB) enrichment broths for different times and conditions. No significant differences were observed in levels of L. monocytogenes from pure cultures in UVM or LEB on any sampling day. No differences were observed in the levels of mixed microflora from Brie cheese in either UVM or LEB, but from chicken rinse the level of mixed flora competitors was significantly higher on all sampling days in LEB as compared to UVM. No differences were observed between a single enrichment in UVM or LEB for 2 d and a transfer to a secondary enrichment tube after 1 d. Overall, the level of mixed microflora capable of growing in enrichment broths was greater from chicken rinse than from Brie cheese. The ratio of L. monocytogenes to mixed microflora which survived the selective enrichments was most favorable for recovery of L. monocytogenes after 2 d of enrichment.

scholarly journals Microbiological Contamination of Honeys from Different Sources in Turkey

2018 ◽  
Vol 62 (1) ◽  
pp. 89-96
Author(s):  
Ayse E. Borum ◽  
Mesut E. Gunes
Keyword(s):  
Clostridium Botulinum ◽  
Hand Washing ◽  
The Other ◽  
Paenibacillus Larvae ◽  
Honey Sample ◽  
Microbiological Contamination ◽  
Other Hand ◽  
Pure Cultures ◽  
Different Sources ◽  
Microbiological Properties

Abstract Honey samples obtained by beekeepers taken from thirty-five different apiaries in Turkey’s region of Marmara were investigated for the presence of microorganism. Each honey sample was examined for the number of total aerobic mesofilic bacteria, coliforms, moulds and yeasts and the presence of Salmonella spp., Clostridium botulinum, along with other aerobic bacteriae such as Paenibacillus larvae and Melissococcus plutonius. In total, fifty-four honey samples of different botanical origins including unifloral (Umbelliferae, Leguminosae, Trifolium, Onobrychis), multifloral and chestnut were evaluated in the means of microbiological properties. Microorganisms were isolated in twenty-eight samples (60.86%) of pure cultures and eighteen samples (39.13%) of mixed cultures. On the other hand, no microorganisms were isolated in eight samples. Bacillus spp, Corynebacterium spp., Streptococcus spp., Staphylococcus spp. C. albicans and Penicillium spp. were isolated and identified in other honey samples. The bacteria counts were 4×102 - 1.4×103 cfu/g for aerobic mesofilic bacteria and 1-185 cfu/g for the fungi. The application of sanitary practices (hand washing, avoidance of sneezing or coughing, etc.) may be effective in controlling contamination by microorganisms. On the other hand, air, equipment and dust may be contributing causes of microbiological contamination. Therefore it is important to take precautions in order to avoid such contamination, even though such factors are often difficult to control.

Effect of inoculum density and quantitative PCR-based detection of Rhizoctonia solani AG-2-1 and Fusarium avenaceum on canola

2014 ◽  
Vol 59 ◽  
pp. 71-77 ◽  
Author(s):  
Qixing Zhou ◽  
Yongyan Chen ◽  
Yalong Yang ◽  
Hafiz U. Ahmed ◽  
Sheau-Fang Hwang ◽  
...  
Keyword(s):  
Rhizoctonia Solani ◽  
Quantitative Pcr ◽  
Inoculum Density ◽  
Fusarium Avenaceum
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