News From The American Chemical Society, Feb. 25, 2009

Two food additives with previously unrecognized estrogen-like effects in two food additives



Scientists in Italy are reporting development and successful use of a fast new method to identify food additives that act as so-called "xenoestrogens" - substances with estrogen-like effects that are stirring international health concerns. They used the method in a large-scale screening of additives that discovered two additives with previously unrecognized xenoestrogen effects. Their report appears in the current edition of ACS' Chemical Research in Toxicology, a monthly journal.



In the study, Pietro Cozzini and colleagues cite increasing concern about identifying these substances and about the possible health effects. Synthetic chemicals that mimic natural estrogens (called "xenoestrogens," literally, "foreign estrogens") have been linked to a range of human health effects. They range from reduced sperm counts in men to an increased risk of breast cancer in women.



The scientists used the new method to search a food additive database of 1,500 substances, and verified that the method could identify xenoestrogens. In the course of that work, they identified two previous unrecognized xenoestrogens. One was propyl gallate, a preservative used to prevent fats and oils from spoiling. The other was 4-hexylresorcinol, used to prevent discoloration in shrimp and other shellfish. "Some caution should be issued for the use of propyl gallate and 4-hexylresocrinol as food additives," they recommend in the study. - MB



ARTICLE: "Identification of Xenoestrogens in Food Additives by an Integrated in Silico and In Vivo Approach"



DOWNLOAD FULL TEXT ARTICLE: pubs.acs/stoken/presspac/presspac/full/10.1021/tx800048m



CONTACT:

Pietro Cozzini, Ph.D.

Department of Biochemistry and Molecular Biology

University of Parma, Parma, Italy



New test for detecting fake organic milk



Scientists in Germany are reporting development of a new, more effective method to determine whether milk marketed as "organic" is genuine or just ordinary milk mislabeled to hoodwink consumers. Their report appears in the current edition of ACS' Journal of Agricultural and Food Chemistry, a bi-weekly publication.



In the study, Joachim Molkentin and colleagues point out that organic milk has soared in popularity in many countries. Sales in Germany, for instance, rose by almost one-third between 2006 and 2007. Consequently, crooks may take advantage of the situation by marketing increasing quantities of fake organic milk. That situation created a need for better tests to detect the fraud.



To address the issue, the scientists developed a test based on an analysis of milk fat for the ratio of stable isotopes of carbon. They used it to identify milk samples from cows raised on feed containing a higher ration of maize. Such a feeding regimen is typical of conventional milk production. Organically raised cows are fed less maize but more pasture feed. In addition, the team identified a significant difference in the alpha-linolenic acid content of milk fat between organic and conventional milk samples. Organic milk typically has a higher alpha-linolenic acid content than conventional milk. - MB
















ARTICLE: "Authentication of Organic Milk Using d13C and the a-Linolenic Acid Content of Milk Fat"



DOWNLOAD FULL TEXT: pubs.acs/stoken/presspac/presspac/full/10.1021/jf8022029



CONTACT:

Joachim Molkentin, Ph.D.

Max Rubner - Institute

Federal Research Institute of Nutrition and Food

Kiel, Germany 24103



"Silver nanoparticle" microscope may shed new light on cancer, bone diseases



In a finding that could help speed the understanding of diseases ranging from cancer to osteoporosis, researchers in Utah are reporting development of a new microscope technique that uses "silver nanoparticle" mirrors to reveal hidden details inside bones, cancer cells, and other biological structures. The method also can help identify structural damage in a wide variety of materials, including carbon-fiber plastics used in airplanes, the researchers say. Their study is scheduled for the March issue of ACS' Nano Letters, a monthly journal.



In the new study, John Lupton and colleagues point out that one of the most powerful, widely used tools for imaging hidden biological structures is fluorescence microscopy, which requires the specimen to be treated with fluorescent dyes or stains. But the dyes used to visualize the structures can kill living cells, limiting the effectiveness of the technique, the researchers note.



The scientists improved on this technique by using an infrared laser to excite clusters of silver nanoparticles, each about 1/5000th the width of a human hair, placed below the material being studied. The particles focus intense beams of light up through the sample to reveal information about the composition and structure of the substance examined, the scientists say. In laboratory studies, they used the new technique to view the iridescent green scales of the so-called "photonic beetle," whose scales may provide clues to designing new, more powerful solar cells and computer chips, the scientists say. - MTS



ARTICLE: "Toward Subdiffraction Transmission Microscopy of Diffuse Materials with Silver Nanoparticle White-Light Beacons"



DOWNLOAD FULL TEXT ARTICLE: pubs.acs/stoken/presspac/presspac/full/10.1021/nl802819n



CONTACT:

John Lupton, Ph.D.

University of Utah

Salt Lake City, Utah 84112



Notes:



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Source: Michael Woods


American Chemical Society