scholarly journals Why it’s time to strengthen and widen the microbial test panel

2021 ◽  
Author(s):  
Tim Sandle
Keyword(s):  
Culture Media ◽  
Growth Promotion ◽  
Human Microbiome ◽  
Test Method ◽  
Raw Material ◽  
Skin Microbiome ◽  
Test Panel ◽  
Intended Application ◽  
Limit Test ◽  
Disinfectant Efficacy

The testing of culture media, and conducting microbiological method suitability studies, disinfectant efficacy studies, Antimicrobial Effectiveness Test (or Preservative Efficacy Test) and associated activities, requires the use of a test panel of microorganisms. These organisms need to be representative of the intended application and be of a suitable range in order to demonstrate that a low level of viable cells can be recovered without any indication of the inhibition of growth or excessive growth-promotion (typically defined as the recovery of between 50 to 200% of the challenge count). This activity provides the basis for the release of culture media or for verifying that a method is suitable for recovering any microorganisms that might be present in a product sample. This approach has been established for several decades and in many cases the types of organisms selected for the panel are drawn from guidance presented in the major pharmacopeia. The test panels of organisms recommended by compendia along with specific standards are in place to allow for reproducibility between laboratories. In the case of most standards (such as the disinfectant efficacy norms), these are designed to be multi-industry. Hence the presented organisms may or may not be suitable for the intended application. In addition, with the compendia, all too often the organisms recommended for, say, the Microbial Limit Test method verification, are applied to the release of all culture media used for all activities, be that the test for sterility or for the recovery of organisms from water systems. Not only is this inappropriate – for the microbiologist should be reviewing the panel and deciding upon the appropriate organisms – the recommended panels have not kept pace with improvements with our understanding of the types of microorganisms likely to cause contamination. Take, for example, the inclusion of Salmonella in the panel for the recovery of so-called ‘objectionable microorganisms’ for use with the Microbial Limits Test ¹. To my knowledge and based on discussions with microbiologists over a couple of decades, no Salmonella has ever been recovered from a raw material. Equally the selection, especially in relation to the testing of culture media used for cleanroom environmental monitoring, has not moved forwards with the findings from the human microbiome project and the depth of species richness found on the human skin microbiome. The argument that the test panel quoted in the compendia is representative and thus if culture media release testing can recover such organisms then it can reasonably be assumed that any other similar organisms can be recovered does not really hold up. Unless, that is, the only concern is with the recovery of non-fastidious mesophilic organisms. Instead, I maintain that in terms of the appropriate panel, this should be based on: • What is currently being recovered, and • What should theoretically be recovered.

Robust Test Method of TSOP PEMs for Space Application

2019 ◽  
Author(s):  
Yasunobu Iwai ◽  
Koichi Shinozaki ◽  
Daiki Tanaka
Keyword(s):  
Evaluation Method ◽  
Low Cost ◽  
Reliability Evaluation ◽  
Test Method ◽  
Thermal Shock Test ◽  
Space Application ◽  
Space Applications ◽  
Limit Test ◽  
Long Time ◽  
Short Time

Abstract Compared with space parts, consumer parts are highly functional, low cost, compact and lightweight. Therefore, their increased usage in space applications is expected. Prior testing and evaluation on space applicability are necessary because consumer parts do not have quality guarantees for space application [1]. However, in the conventional reliability evaluation method, the test takes a long time, and the problem is that the robustness of the target sample can’t be evaluated in a short time. In this report, we apply to the latest TSOP PEM (Thin Small Outline Package Plastic Encapsulated Microcircuit) an evaluation method that combines preconditioning and HALT (Highly Accelerated Limit Test), which is a test method that causes failures in a short time under very severe environmental conditions. We show that this method can evaluate the robustness of TSOP PEMs including solder connections in a short time. In addition, the validity of this evaluation method for TSOP PEM is shown by comparing with the evaluation results of thermal shock test and life test, which are conventional reliability evaluation methods.

scholarly journals Skin bacteria of rainbow trout antagonistic to the fish pathogen Flavobacterium psychrophilum

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mio Takeuchi ◽  
Erina Fujiwara-Nagata ◽  
Taiki Katayama ◽  
Hiroaki Suetake
Keyword(s):  
Rainbow Trout ◽  
Culture Media ◽  
Amplicon Sequencing ◽  
Effective Vaccine ◽  
Rrna Gene ◽  
Skin Microbiome ◽  
Fish Disease ◽  
Flavobacterium Psychrophilum ◽  
Skin Bacteria ◽  
Coldwater Disease

AbstractRainbow trout fry syndrome (RTFS) and bacterial coldwater disease (BCWD) is a globally distributed freshwater fish disease caused by Flavobacterium psychrophilum. In spite of its importance, an effective vaccine is not still available. Manipulation of the microbiome of skin, which is a primary infection gate for pathogens, could be a novel countermeasure. For example, increasing the abundance of specific antagonistic bacteria against pathogens in fish skin might be effective to prevent fish disease. Here, we combined cultivation with 16S rRNA gene amplicon sequencing to obtain insight into the skin microbiome of the rainbow trout (Oncorhynchus mykiss) and searched for skin bacteria antagonistic to F. psychrophilum. By using multiple culture media, we obtained 174 isolates spanning 18 genera. Among them, Bosea sp. OX14 and Flavobacterium sp. GL7 respectively inhibited the growth of F. psychrophilum KU190628-78 and NCIMB 1947T, and produced antagonistic compounds of < 3 kDa in size. Sequences related to our isolates comprised 4.95% of skin microbial communities, and those related to strains OX14 and GL7 respectively comprised 1.60% and 0.17% of the skin microbiome. Comparisons with previously published microbiome data detected sequences related to strains OX14 and GL7 in skin of other rainbow trout and Atlantic salmon.

scholarly journals USE OF SLUDGE FROM SANITARY SEWAGE TREATMENT PLANTS (S.T.P) AND THEIR USE AS RAW MATERIAL IN THE MANUFACTURE OF BRICKS

2019 ◽  
Vol 16 (33) ◽  
pp. 823-840
Author(s):  
M. K. TARABAI ◽  
S. G. de AZEVEDO
Keyword(s):  
Compressive Strength ◽  
Water Absorption ◽  
Sewage Treatment ◽  
Point Of View ◽  
Test Method ◽  
Raw Material ◽  
Environmental Preservation ◽  
Ceramic Block ◽  
Environmental Requirements ◽  
The One

This paper discusses a possible solution regarding the final disposal of sludge from Sanitary Sewage Treatment Stations (ET), aiming at environmental preservation. The solid waste generated after the wastewater treatment processes is highly contaminating and detrimental to the area in which it is deposited. Given this, the use of sludge with the application of reuse techniques becomes pertinent, both from the economic point of view and from the ecological point of view. By replacing the use of aggregates from mineral deposits, the main clay raw material in the manufacture of ceramic products (Vieira, 2000), by the treated sludge of WWTP we will save on the sources of granular materials. Aiming its reintegration to the production cycle through the introduction of sludge as raw material incorporated in the ceramic mass in the manufacture of hollow bricks, the viability of use was verified through performance analysis, compared to the control brick made of pottery, without the addition of sludge. Specimens were prepared with three types of samples: 90% clay and 10% sludge; 80% clay and 20% sludge; 70% clay and 30% sludge. Mass loss, water absorption index and compressive strength tests were performed. As for the tests, the specimens with 10% and 20% of sludge were the ones that had better adaptation to the technical requirements, but because it is a larger volume of the residue for the application of reuse techniques, the brick with 20% sludge dosage. is the most suitable. NBR7.171, November 1992: Ceramic Block for masonry; Specification NBR 6.461, June 1983: Masonry Ceramic Block - Compressive Strength Check: Test Method; NBR 8.947, November 1992: Ceramic Tile- Determination of Mass and Water Absorption: Test Method. As for the tests, the specimen with 20% of sludge was the one that had the best adaptation to technical and environmental requirements. The present article approaches a possible solution regarding the destination of the sludge coming from Sanitary Sewage Treatment Stations, aiming at environmental preservation. Aiming at its reintegration into the productive cycle through applications of reuse techniques, the sludge became raw material when the ceramic mass was incorporated into the brick fabrication. Three types of samples were elaborated: 90% of clay and 10% of mud; 80% clay and 20% sludge; 70% clay and 30% sludge. As for the tests, the test specimen with 20% of sludge was the one that had more adequacy to the technical and environmental requirements.

scholarly journals Utilization of the Django Framework as a Dashboard Model Information System for Raw Material Inventory on PT Bimasakti Karyaprima

2019 ◽  
Vol 1 (2) ◽  
pp. 192-202
Author(s):  
Sandro Alfeno ◽  
Danang Rifai ◽  
Muhammad Saepudin
Keyword(s):  
Web Application ◽  
Swot Analysis ◽  
Raw Materials ◽  
Design Method ◽  
Test Method ◽  
Production Performance ◽  
Raw Material ◽  
Production Section ◽  
Equipment Production ◽  
Office Equipment

The aim of the research is to analyze the raw material inventory and design a dashboard system that can help achieve company goals. The research method used is the method of analysis of stash, software design methods, and methods of software testing. The design analysis method used is the SWOT analysis, the design method used is the design concept using UML diagrams, the soft test method uses the Black Box concept. The results achieved are a dashboard system used by the Warehouse Section and Production Section to monitor raw material inventories and production performance. The conclusion of this study is that the dashboard application that has been made can help the Warehouse and Production Section to monitor raw material inventory and production performance in real time. This web application provides information easily, quickly, concisely and interactively which includes raw materials for shoe components, office equipment, production tools and general equipment, inventory planning, recommendations and reports on transactions and raw material requests. Keywords : Dashboard, Material

Application of a Modified Culture Medium for the Simultaneous Counting of Molds and Yeasts and Detection of Aflatoxigenic Strains of Aspergillus flavus and Aspergillus parasiticus

2003 ◽  
Vol 66 (2) ◽  
pp. 311-318 ◽  
Author(s):  
J. JAIMEZ ◽  
C. A. FENTE ◽  
C. M. FRANCO ◽  
A. CEPEDA ◽  
B. I. VÁZQUEZ
Keyword(s):  
Confidence Interval ◽  
Culture Medium ◽  
Culture Media ◽  
Uv Light ◽  
Raw Materials ◽  
T Test ◽  
Raw Material ◽  
Paired Data ◽  
Significance Level ◽  
Sabouraud Agar

Molds and yeasts from 91 samples of feed and raw materials used in feed formulation were enumerated on a new culture medium to which a beta cyclodextrin (β-W7M 1.8-cyclodextrin) had been added. This medium was compared with other media normally used in laboratories for the routine analysis of fungi, such as Sabouraud agar, malt agar supplemented with 2% dextrose, and potato dextrose agar. When a t test for paired data (0.05 significance level, 95% confidence interval) was applied, no statistically significant differences between the results obtained with the new culture medium and those obtained with the other media used to enumerate molds and yeasts were found. For the evaluation of contamination due to aflatoxin for all of the samples, Sabouraud agar and yeast extract agar, both supplemented with 0.3% β-W7M 1.8-cyclodextrin, and APA (aflatoxin-producing ability) medium were used. Aflatoxin was detected in 21% of the feed samples and in 23% of the raw-material samples analyzed, with maximal amounts of 2.8 and 6.0 μg of aflatoxin B1 per kg, respectively, being detected. In any case, the aflatoxin contents found exceeded the legally stipulated limits. The t test for paired data (0.05 significance level, 95% confidence interval) did not show statistically significant differences between the results obtained with the different culture media used for the detection of aflatoxins. The advantage of the new medium developed (Sabouraud agar with 0.3% β-W7M 1.8-cyclodextrin)is that it allows simultaneous fungal enumeration and determination (under UV light) of the presence of aflatoxin-producing strains without prior isolation and culture procedures involving expensive and/or complex specific media and thus saves work, time, and money.

scholarly journals Macro- and Microelemental Composition and Toxicity of Unsweetened Natural Cocoa Powder in Sprague-Dawley Rats

2016 ◽  
Vol 2016 ◽  
pp. 1-11
Author(s):  
Isaac Julius Asiedu-Gyekye ◽  
Samuel Frimpong-Manso ◽  
Benoit Banga N’guessan ◽  
Mahmood Abdulai Seidu ◽  
Paul Osei-Prempeh ◽  
...  
Keyword(s):  
Test Group ◽  
Scientific Data ◽  
Test Method ◽  
Elemental Content ◽  
High Dose ◽  
Histopathological Analysis ◽  
Sprague Dawley ◽  
Cocoa Powder ◽  
Sprague Dawley Rats ◽  
Limit Test

Unsweetened natural cocoa powder (UNCP) is a pulverized high-grade powder of compressed solid blocks which remains after extraction. Little scientific data is available concerning its safety despite the presence of potential toxic elements. Elemental composition in UNCP was analyzed with ED-XRF spectroscopy. Single oral high dose toxicity study was conducted on adult male Sprague-Dawley rats (150 g) by the limit test method. One group received water and the test group 2000 mg/kg UNCP. All animals were observed for 14 days and then euthanized for haematological, biochemical, and histopathological examinations. Thirty-eight (38) elements were found in UNCP. There was an increase in HDL cholesterol (p<0.05), reduction in LDL cholesterol (p>0.05), alkaline phosphatase (p<0.05), and creatinine levels, and slight increase in urea levels (p>0.05). Haematological changes were not significant. Histopathological analysis showed no toxic effect on the heart, liver, kidney, lungs, testis, and spleen. Intestinal erosion was observed in the test group. UNCP appears to be relatively safe when taken as a single oral high dose of 2000 mg/kg b.w.t. in rats. Caution should however be exercised at high doses due to the high elemental content of copper and high possibility of intestinal lining erosion.

scholarly journals PROMOTION OF REPLICATION IN LYMPHOID CELLS BY SPECIFIC THIOLS AND DISULFIDES IN VITRO

1973 ◽  
Vol 138 (3) ◽  
pp. 574-592 ◽  
Author(s):  
J. D. Broome ◽  
M. W. Jeng
Keyword(s):  
Culture Media ◽  
Growth Promotion ◽  
Lymphoid Cells ◽  
Splenic Lymphocytes ◽  
Mitogenic Response ◽  
Lymphoma Cells ◽  
Structure Activity ◽  
Standard Culture ◽  
Increased Sensitivity

Numerous lines of mouse lymphoid tumors (13 of 22 tested) showed, with increased sensitivity, a property of normal mouse splenic lymphocytes, the potential for growth promotion in vitro by specific thiols added to standard culture media. For lymphoma L1210 (V), structure activity relationships were examined; 9 of 30 thiols promoted growth; the most active was α-thioglycerol, effective at 0.2 µM. Thiols became oxidized under conditions of tissue culture and had half-lives of less than 8 h. Disulfides of active thiols promoted growth of lymphoma cells. The mitogenic response of splenic lymphocytes to lectins was increased by thiols-disulfides which promoted the growth of lymphoma cells, but the response varied with the mitogen preparation used and under some conditions thiols-disulfides were inhibitory.

Use of whey permeate containing in situ synthesised galacto-oligosaccharides for the growth and preservation of Lactobacillus plantarum

2013 ◽  
Vol 80 (3) ◽  
pp. 374-381 ◽  
Author(s):  
Marina Golowczyc ◽  
Carlos Vera ◽  
Mauricio Santos ◽  
Cecilia Guerrero ◽  
Paula Carasi ◽  
...  
Keyword(s):  
Lactobacillus Plantarum ◽  
Culture Media ◽  
Enzymatic Reaction ◽  
Raw Material ◽  
Whey Permeate ◽  
Cheese Industry ◽  
Potential Impact ◽  
And Storage ◽  
Kinetics Of

Galacto-oligosaccharides (GOS) are prebiotics that have a beneficial effect on human health by promoting the growth of probiotic bacteria in the gut. GOS are commonly produced from lactose in an enzymatic reaction catalysed by β-galactosidase, named transglycosylation. Lactose is the main constituent of whey permeate (WP), normally wasted output from the cheese industry. Therefore, the main goal of this work was to optimise the synthesis of GOS in WP using β-galatosidase from Aspergillus oryzaea. WP and whey permeate enzymatically treated (WP-GOS) were used as culture media of Lactobacillus plantarum 299v. Lb. plantarum 299v attained the stationary phase in approximately 16 h, reaching 3·6 and 4·1×108 CFU/ml in WP and WP-GOS, respectively. The in situ synthesised GOS were not consumed during growth. No significant differences were observed in the growth kinetics of microorganisms in both media. After fermentation, microorganisms were dehydrated by freeze-drying and spray-drying and stored. The recovery of microorganisms after fermentation, dehydration and storage at 4 °C for at least 120 d was above 108 CFU/g. These studies demonstrated that WP is an appropriate substrate for the synthesis of GOS and the obtained product is also adequate as culture medium of Lb. plantarum 299v. The coexistence of GOS and dehydrated viable probiotic microorganisms, prepared using an effluent as raw material, represents the main achievement of this work, with potential impact in the development of functional foods.

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