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Therapeutic and subtherapeutic use of veterinary drugs has increased the risk of residue contamination in animal food products. Antibiotics such as tetracycline are used for mastitis treatment of lactating cows. Milk expressed from treated cows before the withdrawal period has elapsed may contain tetracycline residue. This study developed a simple surface-enhanced Raman spectroscopic (SERS) method for on-site screening of tetracycline residue in milk and water. Six batches of silver colloid nanoparticles were prepared for surface enhancement measurement. Milk-tetracycline and water-tetracycline solutions were prepared at seven concentration levels (1000, 500, 100, 10, 1, 0.1, and 0.01 ppm) and spiked with silver colloid nanoparticles. A 785 nm Raman spectroscopic system was used for spectral measurement. Tetracycline vibrational modes were observed at 1285, 1317 and 1632 cm-1 in water-tetracycline solutions and 1322 and 1621 cm-1 (shifted from 1317 and 1632 cm-1, respectively) in milk-tetracycline solutions. Tetracycline residue concentration as low as 0.01 ppm was detected in both the solutions. The peak intensities at 1285 and 1322 cm-1 were used to estimate the tetracycline concentrations in water and milk with correlation coefficients of 0.92 for water and 0.88 for milk. Results indicate that this SERS method is a potential tool that can be used on-site at field production for qualitative and quantitative detection of tetracycline residues. [ABSTRACT FROM AUTHOR]

Past applications of biosolids to soils at some locations added higher Cd levels than presently permitted. Cadmium phytoextraction would alleviate current land use constraints. Unamended farm soil, and biosolids amended farm and mine soils were obtained from a Fulton Co., IL biosolids management facility. Soils contained 0.16, 22.8, 45.3 mg Cd kg–1and 43.1, 482, 812 mg Zn kg–1respectively with initial pH 6.0, 6.1, 6.4. In greenhouse studies, Swiss chard(Beta vulgaris var. cicla), a Cd-accumulator maize (inbred B37Zea mays) and a southern France Cd-hyperaccumulator genotype ofNoccaea caerulescenswere tested for Cd accumulation and phytoextraction. Soil pH was adjusted from ∼5.5–7.0. Additionally 100 rice (Oryza sativa) genotypes and the Ni-hyperaccumulator Alyssum murale were screened for potential phytoextraction use. Chard suffered phytotoxicity at low pH and accumulated up to 90 mg Cd kg–1on the biosolids amended mine soil. The maize inbred accumulated up to 45 mg Cd kg–1with only mild phytotoxicity symptoms during early growth at pH > 6.0.N. caerulescensdid not exhibit phytotoxicity symptoms at any pH, and accumulated up to 235 mg Cd kg–1in 3 months. ReharvestedN. caerulescensaccumulated up to 900 mg Cd kg–1after 10 months. Neither Alyssum nor 90% of rice genotypes survived acceptably. BothN. caerulescensand B37 maize show promise for Cd phytoextraction in IL and require field evaluation; both plants could be utilized for nearly continuous Cd removal. Other maize inbreds may offer higher Cd phytoextraction at lower pH, and mono-cross hybrids higher shoot biomass yields. Further, maize grown only for biomass Cd maximum removal could be double-cropped. [ABSTRACT FROM PUBLISHER]

We have previously developed phytoremediation and phytomining technologies employingAlyssumNi hyperaccumulators to quantitatively extract Ni from soils. Implementation of these technologies requires knowledge of Ni localization patterns for theAlyssumspecies/ecotypes of interest under realistic growth conditions. We investigated Ni uptake and localization in matureAlyssum murale‘Kotodesh’ and ‘AJ9ç leaves. Seedlings were grown in potting mix with an increasing series of NiSO4 addition (0, 5, 10, 20, 40, 80 mmol Ni kg-1), NiC4H6O4 addition (0, 5, 10, 30, 60, 90 mmol Ni kg-1), in Ni-contaminated soil from metal refining operations, and serpentine soil. Plants at Ni levels 0, 5, 10, 20 mmolkg-1 and in native soils grew normally. Plants at 40 mmolkg-1 exhibited the onset of phytotoxicity, and 60, 80, and 90 mmolkg-1 were demonstrably phytotoxic, but symptoms of phytotoxicity abated within 6 months. Cryogenic complement fractures were made from frozen hydrated samples. High-resolution scanning electron microscope (SEM) images were taken of one half. The other half was freeze-dried and examined with SEM and semi-quantitative energy dispersive x-ray analysis. Ni was highly concentrated in epidermal cell vacuoles and Ni and S counts showed a positive correlation. Trichome pedicles and the epidermal tissue from which the trichome grows were primary Ni compartments, but Ni was not distributed throughout trichomes. Palisade and spongy mesophyll and guard/substomatal cells contained lesser Ni concentrations but palisade mesophyll was an increasingly important compartment as Ni soil levels increased. Ni was virtually excluded from vascular tissue and trichome rays. [ABSTRACT FROM AUTHOR]

The polyunsaturated fatty acid (PUFA) composition of the mammalian central nervous system is almost wholly composed of two long-chain polyunsaturated fatty acids (LC-PUFA), docosahexaenoic acid (DHA) and arachidonic acid (AA). PUFA are dietarily essential, thus normal infant/neonatal brain, intellectual growth and development cannot be accomplished if they are deficient during pregnancy and lactation. Uniquely in the human species, the fetal brain consumes 70% of the energy delivered to it by mother. DHA and AA are needed to construct placental and fetal tissues for cell membrane growth, structure and function. Contemporary evidence shows that the maternal circulation is depleted of AA and DHA during fetal growth. Sustaining normal adult human brain function also requires LC-PUFA.Homo sapiens is unlikely to have evolved a large, complex, metabolically expensive brain in an environment which did not provide abundant dietary LC-PUFA. Conversion of 18-carbon PUFA from vegetation to AA and DHA is considered quantitatively insufficient due to a combination of high rates of PUFA oxidation for energy, inefficient and rate limited enzymatic conversion and substrate recycling. The littoral marine and lacustrine food chains provide consistently greater amounts of pre-formed LC-PUFA than the terrestrial food chain. Dietary levels of DHA are 2.5–100 fold higher for equivalent weights of marine fish or shellfish vs. lean or fat terrestrial meats. Mammalian brain tissue and bird egg yolks, especially from marine birds, are the richest terrestrial sources of LC-PUFA. However, land animal adipose fats have been linked to vascular disease and mental ill-health, whereas marine lipids have been demonstrated to be protective. At South African Capesites, large shell middens and fish remains are associated with evidence for some of the earliest modern humans. Cape sites dating from 100 to 18 kya cluster within 200 km of the present coast. Evidence of early H. sapiens is also found around the Rift Valley lakes and up the Nile Corridor into the Middle East; in some cases there is an association with the use of littoral resources. Exploitation of river, estuarine, stranded and spawning fish, shellfish and sea bird nestlings and eggs by Homo could have provided essential dietary LC-PUFA for men, women, and children without requiring organized hunting/fishing, or sophisticated social behavior. It is however, predictable from the present evidence that exploitation of this food resource would have provided the advantage in multi-generational brain development which would have made possible the advent of H. sapiens. Restriction to land based foods as postulated by the savannah and other hypotheses would have led to degeneration of the brain and vascular system as happened without exception in all other land based apes and mammals as they evolved larger bodies. [Copyright &y& Elsevier]

Background: Gradient temperature Raman spectroscopy (GTRS) applies the continuous temperature gradients utilized in differential scanning calorimetry (DSC) to Raman spectroscopy, providing a new means for rapid high throughput material identification and quality control. Methods: Using 20 Mb three-dimensional data arrays with 0.2 °C increments and first/second derivatives allows complete assignment of solid, liquid and transition state vibrational modes. The entire set or any subset of the any of the contour plots, first derivatives or second derivatives can be utilized to create a graphical standard to quickly authenticate a given source. In addition, a temperature range can be specified that maximizes information content. Results: We compared GTRS and DSC data for five commercial fish oils that are excellent sources of docosahexaenoic acid (DHA; 22:6n-3) and eicosapentaenoic acid (EPA; 20:5n-3). Each product has a unique, distinctive response to the thermal gradient, which graphically and spectroscopically differentiates them. We also present detailed Raman data and full vibrational mode assignments for EPA and DHA. Conclusion: Complex lipids with a variety of fatty acids and isomers have three dimensional structures based mainly on how structurally similar sites pack. Any localized non-uniformity in packing results in discrete "fingerprint" molecular sites due to increased elasticity and decreased torsion. [ABSTRACT FROM AUTHOR]