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Cereal Research Communications
Authors:
J. Lu
,
G.Z. Ji
,
G. Li
,
Y.F. Wu
,
J. Yang
,
S.L. Lin
,
D.L. Yang
,
J.N. Zhao
, and
W.M. Xiu

References Arun , O.O. , Yilmaz , F. , Muratogolu , K. 2013 . PCR detection of genetically modified maize and soy in mildly and highly processed foods

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Dell’Acqua A., Sarti A., Tubaro S., Zanzi L. (2004), Detection of linear objects in GPR data. Signal Process, 84, 785–799. Zanzi L. Detection

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Cytochrome P450 CYP141 is an intermediary metabolic and respiratory protein that interferes with oxidation reduction in Mycobacterium tuberculosis. This conserved protein has also been debated as a hypothetical target for therapeutics. We used the sequences of CYP141 gene to develop a PCR for rapid detection of Mycobacterium tuberculosis from respiratory specimens. The sensitivity of this PCR for culture positive-smear positive and culture positive-smear negative samples were 92% and 62.5%, respectively. The overall sensitivity and specificity of this PCR was 85.7% and 97.8%. As compared with other studies, it appears that the CYP141 gene is a good target for direct detection of M. tuberculosis from respiratory specimens.

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Proteases constitute a significant part of cell wall-degrading enzymes (CWDEs) produced by fungal biocontrol agents and particularly crucial in mycoparasitism of fungal phytopathogens. Plate-based screening methods are routinely used for screening protease-producing microorganisms including fungi. Skim milk agar (SMA) is one of the most popular media for the detection of protease producing bacteria. However, SMA is not efficient to test fast growing fungi, because it does not give an estimation of the actual amount of secreted protease produced by fungal inocula. In the current study, the efficacy of two modified plate-screening methods, including split-SMA (SSMA) and minimal medium supplemented with skim milk (MSMW) was assessed for detection of protease production by three representative fungal strains including Trichoderma longibrachiatum strain N, Beauveria bassiana strain B and Purpureocillium lilacinum strain PL. Protease production was revealed on the three tested media by the three strains. However, the halo diameter of the fungal strains (a proxy for protease production) was the smallest on SMA. Furthermore, protease production could not be detected for T. longibrachiatum strain N on SMA due to its fast growth; while it showed the highest protease activity on both modified media compared with the other strains. According to the result of this study, the SSMA medium is an easy and more accurate method compared with the two other different methods as it displays the actual amount of protease produced by fungal strains and therefore this method is recommended for quantitative and qualitative detection of protease production by slow and fast growing fungi.

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Campylobacter jejuni and C. coli are among the most important causes of acute diarrhoea in humans throughout the world. Poultry meat is a major source of Campylobacter infections. Sensitive detection methods are necessary to identify contaminated samples. Detection of campylobacters by culturing is slow and tedious, whereas PCR technology offers the potential for rapid and sensitive detection, however, it may be inhibited when used directly for food or pre-enriched food samples. Different methods for sample and/or DNA preparation were studied to find an optimal combination for sensitive PCR detection of C. coli in enrichment broth. Buoyant density centrifugation (BDC) prior to cell lysis improved PCR detection of C. coli by 100-1000-fold. Preston enrichment broth spiked with 101-102 CFU ml-1 was detected positive after 18 h of enrichment. Specific flaA PCR detection of C. coli in enrichment broth following BDC and simple heat lysis of the cells can be conducted within two working days. This study is a part of the undergoing development of a rapid and sensitive molecular procedure for specific detection of C. coli in foods.

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Owolabi G. M., Swamidas A. S. J., Seshadri R. (2003), Crack detection in beams using changes in frequencies and amplitudes of frequency response functions. Journal of Sound and Vibration, 265(1), 1

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Acta Veterinaria Hungarica
Authors:
M. Tenk
,
Á. Bálint
,
L. Stipkovits
,
Judit Bíró
, and
L. Dencső

A Mycoplasma bovis species-specific PCR assay has been developed with improvement of a previously described method (Ghadersohi et al., 1997). This test and its semi-nested version (Hayman and Hirst, 2003) did not function at all in our hands. A new reverse primer (Mbr2) was designed using previously published sequence data. For testing specificity, DNA was extracted from the most frequently occurring mycoplasma species and bacteria of bovine origin. The new PCR detected only Mycoplasma bovis. Moreover, no cross-reaction was observed with the genetically closest relative species, M. agalactiae. The target organism could be detected in a dose as low as 150 CFU ml-1 in broth cultures using ethidium-bromide-stained agarose gels.

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approach to edge detection , IEEE Trans. Pattern Anal. Mach. Intell , Vol. 8 , No. 6 , 1986 , pp. 679 ‒ 698 . [17] Bölkény I. , Füvesi V

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The incidence and severity of diarrhoea associated with Clostridioides difficile have been increasing exponentially. In 2014, an outbreak with the hypervirulent ribotype 027 strain was firstly reported in Portugal and, among others, this ribotype have been mainly isolated from animals and food. This study aimed to detect and quantify C. difficile from different meats sold in traditional commerce and hypermarkets in two different cities of Portugal, Porto and Lisboa.

Techniques of quantification and detection of C. difficile were performed, but absence of C. difficile in the 143 analysed samples indicates that, if present, the level of contamination should be very low (below 2 log CFU g−1). Despite the lack of confirmed cases of foodborne diseases caused by C. difficile, the increased CDI incidence suggests that contaminated foods may contribute to C. difficile-acquired infections.

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The KLP+ (“hat”) trap baited with pheromone or floral lures is a highly efficient non-sticky trap for the western corn rootworm, Diabrotica v. virgifera. We tested the suitability of this trap design for the related species, D. speciosa and D. barberi, baited with their respective lures. Both species are exotic to Europe: the former inhabits South America, and the latter occurs in some parts of North America.In screening tests performed in Brazil, several synthetic floral compounds and their combinations were found to be attractive to D. speciosa. However, the greatest effect was recorded for the previously described attractant 1,4-dimethoxybenzene. When the most active compounds in the preliminary test, 2-phenylethanol, methyl anthranilate, eugenol or benzaldehyde were added to 1,4-dimethoxybenzene, no synergistic effects were observed. When 1,4-dimethoxybenzene was formulated in three types of polyethylene (PE) dispensers in KLP+ traps, PE bag dispensers were superior to two types of PE vial dispenser, and caught hundreds of D. speciosa. Unbaited traps caught only negligible numbers. There was an interesting non-target effect. KLP+ traps with 1,4-dimethoxybenzene caught large numbers of the cornsilk fly, Euxesta eluta, which is known as a maize pest.For D. barberi, both a pheromone and a potent floral lure are already known. In tests with KLP+ traps, we found that the pheromone and floral lures can be applied together in the same trap to maximize both male and female catches.In conclusion, for early detection programs in Europe, the application of KLP+ traps baited with 1,4-dimethoxybenzene in PE bag dispensers could be recommended for D. speciosa, and KLP+ traps with dual (pheromone and floral) lures for D. barberi. In the case of D. barberi, one should note that the lures also show some attraction for D. v. virgifera, and the ratio of D. barberi vs. D. v. virgifera in the catch will be predominantly determined by the relative population densities at the given site.

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