Smoking of meats and fish is one of the earliest preservation technologies developed by humans. In this study, the smoking process was evaluated as a method for reducing oxidation of pink salmon (Oncorhynchus gorbuscha) oils and also maintaining the quality of oil in aged fish prior to oil extraction. Salmon heads that were subjected to high temperatures (95 degrees C) during smoking unexpectedly produced oils with fewer products of oxidation than their unprocessed counterparts, as measured by peroxide value (PV), thiobarbituric acid reactive substances (TBARS), and fatty acids (FA). Higher temperatures and longer smoking times resulted in correspondingly lower quantities of oxidative products in the oils. Fatty acid methyl ester (FAME) analysis of smoke-processed oils confirmed that polyunsaturated fatty acids (PUFA) were not being destroyed. Smoke-processing also imparted antioxidant potential to the extracted oils. Even when antioxidants, such as ethoxyquin or butylated hydroxytoluene, were added to raw oils, the smoke-processed oils still maintained lower levels of oxidation after 14 d of storage. However, decreased antioxidant capacity of smoke-processed oils was noted when they were heated above 75 degrees C. Vitamin studies supported the antioxidant results, with smoke-processed oils displaying higher levels of alpha-tocopherol than raw oils. Results suggest that smoking salmon prior to oil extraction can protect valuable PUFA-rich oils from oxidation. Improved preservation methods for marine oils may extend their usefulness when added as a supplement to enhance levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in foods.

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Sindbis virus (SIN) is a mosquito-transmitted animal RNA virus. We previously reported that SIN genomes lacking a canonical 19 nt 3'CSE undergo novel repair processes in BHK cells to generate a library of stable atypical SIN genomes with non-canonical 3'A/U-rich elements (NC3AREs) adjacent to the 3' poly(A) tail [1]. To determine the stability and evolutionary pressures on the SIN genomes with NC3AREs to regain a 3'CSE, five representative SIN isolates and a wild type SIN were tested in newborn mice. The key findings of this study are: (a) all six SIN isolates, including those that have extensive NC3AREs in the 3'NTRs, replicate well and produce high titer viremia in newborn mice; (b) 7-9 successive passages of these isolates in newborn mice produced comparable levels of viremia; (c) while all isolates produced only small-sized plaques during primary infection in animals, both small- and large-sized plaques were generated in all other passages; (d) polymerase stuttering occurs on select 3' oligo(U) motifs to add more U residues within the NC3AREs; (e) the S3-8 isolate with an internal UAUUU motif in the 3'poly(A) tail maintains this element even after 9 passages in animals; (f) despite differences in 3'NTRs and variable tissue distribution, all SIN isolates appear to produce similar tissue pathology in infected animals. Competition experiments with wt SIN and atypical SIN isolates in BHK cells show dominance of wt SIN. As shown for BHK cells in culture, the 3'CSE of the SIN genome is not required for virus replication and genome stability in live animals. Since the NC3AREs of atypical SIN genomes are not specific to SIN replicases, alternate RNA motifs of alphavirus genome must confer specificity in template selection. These studies fulfill the need to confirm the long-term viability of atypical SIN genomes in newborn mice and offer a basis for exploring the use of atypical SIN genomes in biotechnology.

Microbial growth can be described using models derived by differential equations, but available mathematical models have yet to adequately describe lag phase related cell growth or cell mortality in response to chemical toxicity. Lag phase cell behavior, however, dictates the onset of exponential growth and the number of actively growing cells available to initiate exponential growth, important factors in the success of remediation efforts. In this study, a five-parameter polynomial ratio (PR) model was used to characterize the growth, from lag through stationary phase, of the yeast Saccharomyces cerevisiae in response to cadmium toxicity. The PR model used in this study has the advantages over standard mathematical models in the ability to represent the initial cell mortality observed when S. cerevisiae is exposed to increasing cadmium levels, up to 12 mg/l Cd, as well as following cell recovery and growth to stationary levels.