Comparison of simplex and duplex real-time PCR for the quantification of GMO in maize and soybean

This paper focuses on the determination of the GMO content of maize and soybean samples using real-time PCR, comparing simplex and duplex PCR. The total DNA content of samples was determined by amplifying part of a maize gene encoding a lipid transfer protein, or part of a soybean lectin gene. The transgenic DNA was quantified by amplifying part of the CaMV 35S promoter. The importance of preparation and conservation of standards as well as the relevance of DNA extraction protocol on the variability of results are discussed. For the determination of low GMO content, limitation in the number of copies of the target gene to be amplified is considered. For samples with a theoretical GMO content of 1%, corresponding to the legal threshold for labelling, the value determined by duplex real-time PCR ranged from 0.85% to 1.20%. Both real-time simplex and duplex PCRs allowed identification of GMO free samples without ambiguity.     

Efficacy of filter cake and Triplex powders from Ethiopia against three externally developing stored product insect species

Efficacy of filter cake and Triplex powders was evaluated against the red flour beetle, Tribolium castaneum (Herbst); saw-toothed grain beetle, Oryzaephilus surinamensis (L.); and Indian meal moth, Plodia interpunctella (Hübner). Mortality of T. castaneum and O. surinamensis was determined 14 d after exposing 20 adults to 100 g of maize and wheat treated with 0, 0.3, 0.5, 0.7, 1, 2, and 3 g/kg of filter cake and 0, 0.5, 0.7, 1, 2, 3, 6, 8, and 10 g/kg of Triplex. Adult progeny production was determined at 42 d. Live larvae at 21 d and adults of P. interpunctella that emerged at 42 d were determined by exposing 100 eggs to 0, 0.2, 0.3, 0.5, 0.7, 1, 2, and 3 g/kg of filter cake and 0, 0.3, 0.5, 0.7, 1, 2, 3, 6, and 8 g/kg of Triplex treated maize and wheat. On both grains, 100% mortality of T. castaneum and O. surinamensis adults was observed after exposure to 2–3 and 1–3 g/kg of filter cake, respectively. On wheat, 100% mortality only of O. surinamensis was observed in 2–3 g/kg Triplex treatment. Adult progeny production of T. castaneum and O. surinamensis was completely suppressed on both grains treated with 0.7–3 g/kg of filter cake. Adult progeny production of T. castaneum was completely suppressed at 1–3 g/kg of Triplex treated grains, whereas complete suppression of O. surinamensis was achieved only on maize treated with 2–3 g/kg of Triplex. Both live larvae at 21 d and adults of P. interpunctella that emerged at 42 d were completely suppressed when eggs were exposed to 2–3 and 0.5–3 g/kg filter cake treated maize and wheat, respectively, and on 6–8 and 3 g/kg Triplex treated maize and wheat, respectively. Filter cake was more efficacious compared to Triplex on both grains.     

双齿围沙蚕美拉德反应产物的制备及其抗氧化活性初探

利用酸解法水解双齿围沙蚕干品得到氨基酸水解液,再分别与葡萄糖、蔗糖进行美拉德反应制备美拉德反应产物（MRPs）,采用硫氰酸铁法研究其抗氧化活性。结果表明：制备得到的两种沙蚕美拉德反应产物均具有一定的抗氧化活性。在受试时间内,沙蚕和葡萄糖MRPs的抗氧化活性在作用4h之前弱于没食子酸丙酯,在作用4h之后优于没食子酸丙酯;而沙蚕和蔗糖MRPs的抗氧化活性在受试7.5h以内弱于没食子酸丙酯,且其抗氧化活性呈逐渐减弱的趋势,而在7.5h以后其抗氧化活性呈现增强的趋势。     

Mapping haze-komi on rice koji grains using β-glucuronidase expressing Aspergillus oryzae and mass spectrometry imaging

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Immobilization of surface non-affinitive protein onto a metal surface by an external electric field

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Significant population structure in Australian Cryptolestes ferrugineus and interpreting the potential spread of phosphine resistance

An analysis of the population genetics of Cryptolestes ferrugineus, across all major regions in Australia where grain is grown and stored in bulk, provides an initial step in investigating the movement of these insects and implications for the spread of phosphine resistance. Microsatellite data revealed two levels of genetic structure. Across Australia, two clusters were detected, one in eastern Australia (Queensland, New South Wales, Victoria and Tasmania) and Western Australia (Cluster 1) and one in South Australia (Cluster 2). Intermediate between them, in eastern South Australia, are a couple of populations that are equally admixed for the two clusters. Populations in Western Australia and western SA belong to different clusters suggesting that the extensive and arid Nullarbor Plain restricts the natural dispersal of these beetles. Isolation-by-distance and the detection of clustering among local populations suggests there is considerable gene flow at a local scale in C. ferrugineus, and we infer this is by flight. Limited natural gene flow between eastern and western Australia might, in part, explain why extremely high resistance has not been detected in Western Australia.     

Stream nutrient and agricultural land-use trends from 1971 to 2010 in Lake Ontario tributaries

Urbanization is generally recognized as the most widespread form of landuse/landcover change (LULC) within populated regions, including southern Ontario, and is often at the expense of surrounding agricultural land. However, changes in agricultural LULC within these peripheral regions should be considered when interpreting water quality changes in watersheds containing mixed LULC. The objectives of this study were to first, quantify changes in LULC within twelve Lake Ontario tributaries between 1971 and 2010, and secondly, to determine whether these changes co-occurred with changes in total phosphorus (TP) and nitrate‑nitrogen (NO₃-N) concentrations in streams. Water quality data were obtained from the Ontario Provincial Water Quality Monitoring Network while historical land use was reconstructed from agricultural census reports, historical land cover maps, and modern remotely sensed datasets. Urban cover increased, although percent increases in urban cover were small in the most agriculturally dominated watersheds (3–8%). The area of agriculture declined across all watersheds, yet the proportion of agricultural land dedicated to crop (corn, soybean, and wheat) production increased, including in the most urbanized watersheds (e.g. Mimico 89% urban; 2009–11). Total P concentrations in streams were highest at the urbanized watersheds, particularly in the 1970s, before declining in recent decades. In contrast, NO₃-N concentrations were highest (>1.5 mg/L; 2000–10) within the most agricultural watersheds (e.g. Gages 71% agriculture) and have increased over the same period of row crop expansion. Further research is needed to determine the mechanisms behind the potential relationship between expanding row crop cover and stream NO₃-N concentrations in southern Ontario.