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News Article | August 22, 2016
Site: http://phys.org/chemistry-news/

High-fructose corn syrup and sugar are on the outs with calorie-wary consumers. As a result, low- and no-calorie alternatives have become popular, and soon, there could be another option that tastes more sugar-like than other substitutes. Scientists report in ACS' Journal of Agricultural and Food Chemistry a step toward commercial production of a fruit protein called brazzein that is far sweeter than sugar—and has fewer calories.


News Article | February 3, 2016
Site: http://phys.org/chemistry-news/

It's well known that peanuts can cause severe reactions in people who are allergic, but research suggests that the risk of developing a life-threatening reaction could be higher for those allergic to cashews. Now scientists have come up with a fast and simple method to purify the three main cashew allergens to help better grasp how they work and their effects on people. Their report appears in ACS' Journal of Agricultural and Food Chemistry.


News Article
Site: http://phys.org/chemistry-news/

The research involves the use of manganese oxide minerals to break down glyphosate and to identify released phosphate and other byproducts such as AMPA. The researchers used oxygen isotopes of released phosphate from glyphosate and compared that from other phosphorous compounds present in soils and other environments with an aim to discriminate and track the sources. The research findings were published recently in the Journal of Agricultural and Food Chemistry based on work conducted by Hui Li and Sunendra Joshi, both doctoral students working with Deb Jaisi in the Department of Plant and Soil Sciences in UD's College of Agriculture and Natural Resources (CANR). Glyphosate is integral to agricultural production but because of its widespread application—the United States Geological Survey (USGS) estimated that 283 million pounds were used in 2012—there have been health-related concerns about the presence of the compound and AMPA in soils, streams and other environments. Jaisi said the research is looking at the different mechanisms and pathways glyphosate can be degraded in the soil that are catalyzed either by the action of bacteria or minerals. The research team focused on the mineral-catalyzed (abiotic) degradation, and compared the degradation kinetics of glyphosate with AMPA. "Eventually, we would like to see excess of these compounds after herbicidal action that may end up in soil and other environment degrade down sooner rather than later to minimize any potential environmental harm," said Jaisi. They found that manganese oxide, one of the inherent minerals in soil, is an efficient mineral that could break down glyphosate and AMPA. The research group synthesized manganese oxide in the laboratory and found that the half-life—or the amount of time required for the amount of glyphosate and AMPA to fall to half of its initial value—was around 3 and 48 hours for glyphosate and AMPA, respectively. With regard to AMPA, Li said it is a major intermediate byproduct of glyphosate—formed after a particular bond in the glyphosate is broken down but before it eventually forms final inorganic products—that accumulates in the natural environment at a much higher rate than glyphosate itself because it degrades much more slowly than glyphosate. Some research indicates that it is more toxic than glyphosate. "We want to figure out whether the mineral we were using can break down AMPA, as well as glyphosate. If it does break down to AMPA, the second question is can we trace the source of AMPA. This is important because AMPA is also a byproduct of other organic phosphorous compounds. Furthermore, glyphosate degrades through another pathway as well and that pathway does not generate AMPA," said Li. Jaisi said that because the experiment was entirely laboratory-based, it is too early to say how well the results can be extended to a real environment. A lot would depend on how much manganese oxide resides in the environment and how much it would be able to interact with glyphosate. Another challenge is methodological and involves the separation and purification of the two compounds from environmental samples, which they are going to address next in their research. "There's a lot of things in between to be resolved in a real environment, but at least we have something in the environment that can break it down, so that's a good thing," said Jaisi. With regard to tracking the glyphosate, Li said that the most innovative aspect of the paper was "validating a novel method, oxygen isotope signature of the compound, to trace glyphosate sources in the environment and differentiate phosphate released from glyphosate from other sources of phosphates." Li added, "A natural extension of this research is to apply this tool in real field samples. So we also want to apply a series of advanced methods to address some very basic questions like what minerals in soils induce the degradation of glyphosate, or is there a way to bias reaction towards a relatively harmless product pathway, or catalyze faster degradation to minimize the potential environmental impact." Jaisi likened the source tracking to an identifying feature in humans, like a fingerprint or DNA. "Your DNA and my DNA is going to be different. Our expertise is on identification of sources of different phosphorus compounds and tracking them in the environment. For this, we need to know first the original isotope signature of the glyphosate that ends up in the environment," said Jaisi. If it does remain in the environment for a good chunk of time, the method has the potential to identify its sources. "The second question is, if more than one source of glyphosate ends up in soils, can we discriminate them? There is lot more research to be done in that direction but if we are successful in our objectives, it may allow tracking particular sources as they degrade in soils over time. Existing methodology is the lump sum measurement of the compound, but our ability to differentiate each product by isotope signature brings new insights not only to source identification of a particular product but also to identify accurate half-lives of these products," said Jaisi. For the study, the researchers used five different commercial herbicide brands from different companies to see if the different products had different fingerprints and are still different from other phosphate sources in the environment. Joshi said the phosphate released from the breakdown of limited glyphosate products studied "has a unique isotopic signature than other phosphate in the environment we know so far. If we measure the isotopic signatures of all phosphate types in the natural environment and found one having a peculiar isotopic signature, then we would have reasonable certainty to say, 'This phosphorous is coming from that particular source.'" Explore further: EU downplays cancer risk from weedkiller in win for Monsanto (Update)


News Article
Site: http://phys.org/chemistry-news/

The crimson stigma of the saffron flower (Crocus sativus) is one of the oldest and most expensive spices in the world, particularly those varieties which are internationally recognised for their quality, such as saffron grown in Spain. This has led to the fraudulent labelling of non-Spanish saffron. "Over the past few years the media have been reporting this fraudulent activity, but up until now there were barely any analytical tools that could be used to detect said fraud. So, we created a new strategy to determine the authenticity of saffron based on metabolomics or, in other words, the chemical fingerprints of foods," explains Josep Rubert, a researcher at University of Chemistry and Technology (UCT Prague, Czech Republic) and the University of Valencia (Spain). The new technique allows for three types of saffron to be defined: one which is certified with the Protected Designation of Origin (PDO) from La Mancha or Aragon, another which is grown and packaged in Spain (although it does not have the PDO certificate) and a third category which is packaged as 'Spanish saffron' but, despite its name, is of unknown origin (although most likely packaged in Spain). With these possibilities, scientists from the UCT Prague leaded by Prof. Jana Hajslova—and where Rubert is also carrying out postdoctoral research including this study —, collected 44 commercial saffron samples in order to test the authenticity of what's stated in the product labels. The findings, published this month by the journal Food Chemistry, revealed that more than 50% of the samples were fraudulent, as 26 ones labelled as 'Spanish saffron' were neither grown nor processed in Spain. "It is highly likely that lower quality saffron is purchased in other countries (such as Morocoo, Iran and India according to our data) at a much lower price than in Spain -indicates the researcher —, to later be packaged and sold as Spanish saffron despite being of unknown origin a fraudulent activity that gambles with consumers' trust". The technique developed by scientists from the Czech Republic and Spain has confirmed that the saffron labelled with the PDO Certificate from La Mancha (and Aragon) were indeed grown and processed in Spain. "Here there was no fraudulent activity the saffron perfectly matched up with our models," emphasises Rubert, "unlike the samples of 'Spanish saffron' that had either a completely different chemical fingerprint or a different collection of small molecules". Chemistry and statistics to expose the fraud The authors of this study combined chemistry with statistics in order to develop their methodology. The first phase of the study consisted in identifying the metabolites or small molecules characteristic of saffron. After, a method was created to detect these small molecules using liquid chromatography coupled with high-resolution mass spectrometry. On one hand, the statistical analyses have served to detect the clear differences between the three types of saffron in addition to validating the technique. According to the authors, the result "is a top-quality model that correctly classified 100% of these samples in addition to having the capacity to correctly categorise others (even if they are unknown and do not have a label) more than 85% of the time". The authors suggest that glycerophospholipids and their oxidised lipids are the best molecular markers for determining the origin of saffron. They have also observed that the saffron technology and processing play a crucial role, "specifically during the drying process, wherein transformation of the product is determined by the temperature at which the process is carried out. The place where the saffron originates also has an influence on the end product". For saffron originating from La Mancha, for example, the drying process involves laying out the fresh stigmas over sieves that are placed next to a heat source such as a fire, hot coal, a stove or a brazier. Saffron dehydration happens quickly -in half an hour- and is carried out at a temperature of 70 ºC which accelerates lipid oxidation. Over recent decades, saffron originating from Castile-La Mancha has represented over 97% of Spain's domestic production a statistic that presents an enormous gap with regard to exportations. Between 1997 and 2013, an average of 2,813 kg of saffron was produced annually in Spain. However, Spain exported 35,978 kg of this product on average each year. Where did those remaining 33,165 kg come from? "They came from other countries, such as Iran or Morocco," mentions Pedro M. Pérez again, manager of the Protected Designation of Origin Regulatory Body in La Mancha. He insists that: "That foreign saffron is brought to Spain and labelled as 'produced and packaged in Spain', which is true, but the label fails to indicate the saffron's true origin, meaning that the consumer does not have enough information to assess the product". The manager of the regulatory body reiterates that there is a Spanish national law dated 1999 in addition to a European law from 2011 regarding the proper labelling of foodstuffs, "but the competent authorities of Spain's Autonomous Communities are not successfully fulfilling their responsibilities with regard to saffron". Explore further: Smartphone maker HTC invests in UK, US firms More information: Josep Rubert et al. Saffron authentication based on liquid chromatography high resolution tandem mass spectrometry and multivariate data analysis, Food Chemistry (2016). DOI: 10.1016/j.foodchem.2016.01.003


News Article | September 8, 2016
Site: http://www.chromatographytechniques.com/rss-feeds/all/rss.xml/all

For many people, there's nothing more satisfying than a hot, spicy meal. But some research has suggested that capsaicin, the compound that gives chili peppers their kick, might cause cancer. Now researchers show in mouse studies that the pungent compound in ginger, 6-ginergol, could counteract capsaicin's potentially harmful effects. In combination with the capsaicin, 6-gingerol could lower the risk of cancer, they say. The study appears in ACS' Journal of Agricultural and Food Chemistry. Both chili peppers and ginger are widely used spices in certain cuisines, particularly in Asia, and have been studied for potential health effects. Although some studies have shown that peppers can have benefits, others suggest that diets rich in capsaicin might be associated with stomach cancer. Ginger, however, has shown promise as a health-promoting ingredient. Oddly enough, capsaicin and 6-gingerol both bind to the same cellular receptor -- one that is related to tumor growth. Jiahuan Li, Gangjun Du and colleagues wanted to further investigate this apparent contradiction. Over several weeks, the researchers fed mice prone to lung cancer either capsaicin or 6-gingerol alone, or a combination of both. During the study period, all of the mice that received only capsaicin developed lung carcinomas while only half of the mice fed 6-gingerol did. Surprisingly, an even lower percentage -- only 20 percent -- of the mice given both compounds developed cancer. The researchers also dug into the potential molecular underpinnings of how the compounds interact to lead to this effect.

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