Product Authentication Using Two Mitochondrial Markers Reveals Inconsistent Labeling and Substitution of Canned Tuna Products in the Taiwanese Market.

Fish of the tribe Thunnini represent a significant proportion of the stock caught by the fishing industry, with many of these fishes being collectively called tuna. However, only certain species can be used legally as an ingredient in canned tuna products, depending on regional food regulations. In Taiwan, only Thunnus species or Katsuwonus pelamis can be used as canned tuna. Here, we authenticated 90 canned tuna products, including 25 cat food samples, by sequencing two mitochondrial regions, 16S rRNA (16S) and the control region (CR). BLAST analysis revealed that Sarda orientalis, Euthynnus affinis, Auxis rochei, and Auxis thazard are all used as substitutes for legitimate tuna products. We found that 63.33% of investigated samples are true canned tuna, i.e., contain Thunnus species or skipjack tuna. We advocate that the Taiwanese government publishes an official standardized list of fishes, especially so that scientific, Chinese and vernacular names can be assigned unambiguously based on a "one species-one name policy", thereby clarifying which species can be used in seafood products such as tuna. Furthermore, we feel that the large-scale and long-term monitoring of canned tuna products is warranted to fully assess the extent of tuna product adulteration in Taiwan.

Moderating effect of regulatory focus on burnout and exercise behavior.

Applying Higgins' regulatory focus, which assumes that people pursue goals using means that match their self-regulatory motivation, the authors examined whether individual's promotion- or prevention-focused motivations in work would decrease participation in physical activity. Participants were 197 employees (163 men, 34 women, M age = 39 yr.) in five different Taiwanese manufacturing firms. They responded to Copenhagen Burnout Inventory, the Regulatory Focus Questionnaire, and Exercise Behavior at two different times, 8-10 weeks apart. Promotion-oriented regulatory focus significantly moderated the relationship between burnout and exercise, but prevention-oriented focus did not. BMI, blood pressure, cholesterol, and work hours contributed small but significant amounts of variance. A prevention focus was associated with more time for physical activity, even when participants were tired, supporting regulatory focus theory.