The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
B Bist - One of the best experts on this subject based on the ideXlab platform.
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comparison of elisa and pcr vis a vis Cultural Methods for detecting aeromonas spp in foods of animal origin
International Journal of Food Microbiology, 2006Co-Authors: Sushrut Arora, R K Agarwal, B BistAbstract:The present study was conducted to assess the best method of the most commonly used Methods for detection of aeromonads in foods of animal origin. With this objective an OMP based indirect plate ELISA and a duplex-PCR using primers targeting aerolysin gene and 16S rRNA gene and yielding amplicons of 252 bp and 599 bp, respectively, were standardized. The standardized protocols and the conventional Cultural method were then compared for their respective sensitivities and specificities for detecting aeromonads from chicken and milk samples. Both the standardized assays were found to be highly specific for Aeromonas. The efficiency of the standardized indirect-ELISA and duplex-PCR protocols was assessed by artificial inoculation studies with varying concentrations of Aeromonas cells inoculated in chicken and milk samples followed by enrichment in Alkaline Peptone Water supplemented with 10 mg/ml cephalothin (APW-C) for 12 h. The results revealed that indirect-ELISA was able to detect a minimum of 103 cells/ml or g of Aeromonas cells in spiked milk and chicken samples, respectively. Whereas, duplex-PCR and Cultural method were able to detect as low as 1 cell/ml or g of Aeromonas cells in spiked milk and chicken samples. The developed assays were also tested for their efficiency to detect Aeromonas spp. in naturally contaminated milk and chicken samples. Out of a total 50 milk samples screened for presence of Aeromonas by the three Methods viz., indirect-ELISA, duplex-PCR and Cultural method only 1 (2%) turned out to be positive showing positive results by all three Methods. Similarly, 50 samples of chicken were tested by all three Methods. Three samples (6%) turned out to be positive and here again by all the three Methods.
R A C Jones - One of the best experts on this subject based on the ideXlab platform.
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minimising losses caused by zucchini yellow mosaic virus in vegetable cucurbit crops in tropical sub tropical and mediterranean environments through Cultural Methods and host resistance
Virus Research, 2011Co-Authors: B A Coutts, Monica A Kehoe, R A C JonesAbstract:Abstract Between 2006 and 2009, 10 field experiments were done at Kununurra, Carnarvon or Medina in Western Australia (WA) which have tropical, sub-tropical and Mediterranean climates, respectively. These experiments investigated the effectiveness of Cultural control measures in limiting ZYMV spread in pumpkin, and single-gene resistance in commercial cultivars of pumpkin, zucchini and cucumber. Melon aphids ( Aphis gossypii ) colonised field experiments at Kununurra; migrant green peach aphids ( Myzus persicae ) visited but did not colonise at Carnarvon and Medina. Cultural control measures that diminished ZYMV spread in pumpkin included manipulation of planting date to avoid exposing young plants to peak aphid vector populations, deploying tall non-host barriers (millet, Pennisetum glaucum ) to protect against incoming aphid vectors and planting upwind of infection sources. Clustering of ZYMV-infected pumpkin plants was greater without a 25 m wide non-host barrier between the infection source and the pumpkin plants than when one was present, and downwind compared with upwind of an infection source. Host resistance gene zym was effective against ZYMV isolate Knx-1 from Kununurra in five cultivars of cucumber. In zucchini, host resistance gene Zym delayed spread of infection (partial resistance) in 2 of 14 cultivars but otherwise did not diminish final ZYMV incidence. Zucchini cultivars carrying Zym often developed severe fruit symptoms (8/14), and only the two cultivars in which spread was delayed and one that was tolerant produced sufficiently high marketable yields to be recommended when ZYMV epidemics are anticipated. In three pumpkin cultivars with Zym , this gene was effective against isolate Cvn-1 from Carnarvon under low inoculum pressure, but not against isolate Knx-1 under high inoculum pressure, although symptoms were milder and marketable yields greater in them than in cultivars without Zym . These findings allowed additional Cultural control recommendations to be added to the existing Integrated Disease Management strategy for ZYMV in vegetable cucurbits in WA, but necessitated modification of its recommendations over deployment of cultivars with resistance genes.
Andrea Monti - One of the best experts on this subject based on the ideXlab platform.
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are we ready to cultivate sweet sorghum as a bioenergy feedstock a review on field management practices
Biomass & Bioenergy, 2012Co-Authors: Walter Zegadalizarazu, Andrea MontiAbstract:This review discusses the potential production for energy purposes of sweet sorghum (Sorghum bicolor L.), a C4 crop native to tropical areas with juicy stalks rich in sugars from which ethanol could be produced at lower costs than from starchy crops like maize. The growing interest in bioenergy and particularly in bioethanol is a great challenge for this relatively new crop that could be used for both thermo-electrical energy and biofuel. Nonetheless, the quantitative and qualitative production of sweet sorghum strongly depends on the use of appropriate and improved agronomic management techniques which is, in some aspects, still largely unknown. This review attempts to gather the sparse information on best agriCultural practices for sweet sorghum, still very much a wild species in many aspects, while identifying the weak points that need to be deepened in further researches, especially under temperate climates. Sweet sorghum is a row crop and therefore the agronomic management and other well known Cultural Methods used for conventional row crops such as maize can be adapted. In general, low input requirements, low production costs, drought resistance, versatility, and high yields gives to sweet sorghum a better energy balance compared to other competing energy crops, especially if bagasse is also processed to energy. In non-traditional potential growing areas (such as in temperate climates of Europe) where productivity/adaptation improvements through genetically modified crops is not allowed, appropriate and sustainable agriCultural practices constitute the most immediate option to improve yields. Based on scientific reports, research efforts seem particularly needed for harvesting techniques, and handling and storing.
B A Coutts - One of the best experts on this subject based on the ideXlab platform.
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minimising losses caused by zucchini yellow mosaic virus in vegetable cucurbit crops in tropical sub tropical and mediterranean environments through Cultural Methods and host resistance
Virus Research, 2011Co-Authors: B A Coutts, Monica A Kehoe, R A C JonesAbstract:Abstract Between 2006 and 2009, 10 field experiments were done at Kununurra, Carnarvon or Medina in Western Australia (WA) which have tropical, sub-tropical and Mediterranean climates, respectively. These experiments investigated the effectiveness of Cultural control measures in limiting ZYMV spread in pumpkin, and single-gene resistance in commercial cultivars of pumpkin, zucchini and cucumber. Melon aphids ( Aphis gossypii ) colonised field experiments at Kununurra; migrant green peach aphids ( Myzus persicae ) visited but did not colonise at Carnarvon and Medina. Cultural control measures that diminished ZYMV spread in pumpkin included manipulation of planting date to avoid exposing young plants to peak aphid vector populations, deploying tall non-host barriers (millet, Pennisetum glaucum ) to protect against incoming aphid vectors and planting upwind of infection sources. Clustering of ZYMV-infected pumpkin plants was greater without a 25 m wide non-host barrier between the infection source and the pumpkin plants than when one was present, and downwind compared with upwind of an infection source. Host resistance gene zym was effective against ZYMV isolate Knx-1 from Kununurra in five cultivars of cucumber. In zucchini, host resistance gene Zym delayed spread of infection (partial resistance) in 2 of 14 cultivars but otherwise did not diminish final ZYMV incidence. Zucchini cultivars carrying Zym often developed severe fruit symptoms (8/14), and only the two cultivars in which spread was delayed and one that was tolerant produced sufficiently high marketable yields to be recommended when ZYMV epidemics are anticipated. In three pumpkin cultivars with Zym , this gene was effective against isolate Cvn-1 from Carnarvon under low inoculum pressure, but not against isolate Knx-1 under high inoculum pressure, although symptoms were milder and marketable yields greater in them than in cultivars without Zym . These findings allowed additional Cultural control recommendations to be added to the existing Integrated Disease Management strategy for ZYMV in vegetable cucurbits in WA, but necessitated modification of its recommendations over deployment of cultivars with resistance genes.
Willis M. Fedio - One of the best experts on this subject based on the ideXlab platform.
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Detection and Isolation of Low Levels of E. coli O157:H7 in Cilantro by Real-Time PCR, Immunomagnetic Separation, and Cultural Methods with and without an Acid Treatment
Journal of food science, 2012Co-Authors: Ken J. Yoshitomi, Karen C. Jinneman, Ruben Zapata, Stephen D. Weagant, Willis M. FedioAbstract:UNLABELLED Leafy greens such as cilantro, contaminated with Escherichia coli O157:H7, have been implicated in cases of human illnesses. High levels of microflora in fresh cilantro make recovery of low numbers of E. coli O157:H7 difficult. To improve upon current Methods, immunomagnetic separation (IMS) techniques in combination with real-time PCR (RTiPCR) and selective enrichment protocols were examined. Rinsates were prepared from cilantro samples inoculated with low (~0.02 CFU/g) and slightly higher (~0.05 CFU/g) levels of E. coli O157:H7. Rinsate portions were enriched in modified buffered peptone water with pyruvate (mBPWp) for 5 h at 37 °C. After 5 h, selective agents were added to samples and further incubated at 42 °C overnight. Detection and recovery were attempted at 5 and 24 h with and without IMS. IMS beads were screened by RTiPCR for simultaneous detection of stx1, stx2, and uidA SNP. Additionally, broth cultures and IMS beads were streaked onto selective agar plates (Rainbow(®) agar, R&F(®) E. coli O157 Chromogenic medium, TC-SMAC and CHROMagar™ 0157) for isolation of E. coli O157:H7. Both broth cultures and IMS beads were also acid treated in Trypticase Soy Broth pH 2 prior to plating to selective media to improve upon Cultural recovery. Although E. coli O157 strains were detected in most samples by PCR after 5 h enrichment, Cultural recovery was poor. However, after 24 h enrichment, both PCR and Cultural recovery were improved. Acidification of the broths and the IMS beads prior to plating greatly improved recovery from 24 h enrichment broths by suppressing the growth of competing microorganisms. PRACTICAL APPLICATION Detection and recovery of Escherichia coli O157:H7 in fresh produce matrices (e.g., cilantro) can be complicated by high background microflora present in these foods. Rapid detection by molecular Methods combined with effective enrichment and isolation procedures such as using immunomagnetic separation (IMS) techniques can quickly identify potential hazards to public health. Additional techniques such as acidification of enrichment broths can exploit acid resistance characteristics of pathogens such as E. coli O157:H7, facilitating their isolation in complex food matrices.
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detection of e coli o157 h7 in raw ground beef by pathatrix immunomagnetic separation real time pcr and Cultural Methods
International Journal of Food Microbiology, 2011Co-Authors: Willis M. Fedio, Ken J. Yoshitomi, Karen C. Jinneman, Ruben Zapata, Chitra Wendakoon, Paul Browning, Stephen D. WeagantAbstract:Detection of Escherichia coli O157:H7 by conventional Cultural Methods can be difficult in food matrices with a high background flora such as raw ground beef. Raw ground beef samples, artificially contaminated separately with five strains of E. coli O157:H7 at low (~0.2 cfu/g) and high (~2 cfu/g) levels, were enriched by two enrichment protocols; buffered peptone water (BPW) at 37 °C for 5h and 24h and modified buffered peptone water with pyruvate (mBPWp) for 5h at 37 °C followed by adding selective agents and incubating at 42 °C to 24h. Detection of added E. coli O157:H7 by real-time PCR (RTiPCR) and recovery on isolation agars was performed before and after PATHATRIX™ immunomagnetic separation (IMS). RTiPCR detection and Cultural recovery of inoculated E. coli O157:H7 after 5h enrichment were poor at 0.21-0.24 cfu/g. The addition of IMS after 5h enrichment did not improve RTiPCR detection but markedly improved recovery by culturing. By extending enrichment to 24h, RTiPCR detection improved to 76% for either enrichment protocol without IMS. When 24h enrichment was followed by IMS, RTiPCR detection was also further improved. Cultural recovery after 24h enrichment was 56% and 84% without IMS and 100% and 92% after IMS for BPW and mBPWp respectively. Extended enrichment to 24h followed by IMS was found to be sensitive and reliable for detection and Cultural recovery from raw ground beef using either enrichment method.