Waste management under a life cycle approach as a tool for a circular economy in the canned anchovy industry.

The anchovy canning industry has high importance in the Cantabria Region (North Spain) from economic, social and touristic points of view. The Cantabrian canned anchovy is world-renowned owing to its handmade and traditional manufacture. The canning process generates huge amounts of several food wastes, whose suitable management can contribute to benefits for both the environment and the economy, closing the loop of the product life cycle. Life cycle assessment methodology was used in this work to assess the environmental performance of two waste management alternatives: Head and spine valorisation to produce fishmeal and fish oil; and anchovy meat valorisation to produce anchovy paste. Fuel oil production has been a hotspot of the valorisation of heads and spines, so several improvements should be applied. With respect to anchovy meat valorisation, the production of polypropylene and glass for packaging was the least environmentally friendly aspect of the process. Furthermore, the environmental characterisation of anchovy waste valorisation was compared with incineration and landfilling alternatives. In both cases, the valorisation management options were the best owing to the avoided burdens associated with the processes. Therefore, it is possible to contribute to the circular economy in the Cantabrian canned anchovy industry.

PAHs composition of surface marine sediments: a comparison to potential local sources in Todos Santos Bay, B.C., Mexico.

The analysis of the 16 polyaromatic hydrocarbons (PAHs) listed as priority pollutants by EPA, was carried out on surface sediments at 32 stations at Todos Santos Bay, Baja California, Mexico. The purpose was to investigate concentration levels, distribution patterns and relate them to three suspected local sources. The PAHs composition of car exhaust, grass and shrubs combustion, and asphalt and tire dust, were all compared to the relative abundance of PAHs signature found on marine sediments of the bay. We used GC-MS analysis in selected ion monitoring (SIM) mode. The total concentration found was low (from 7.6 to 813 ng/g of dry sediment. The average concentration was 96 ng/g). PAHs concentration was somewhat correlated (r = 0.612; P < 0.05) with organic matter content. Surface distributions suggest depositional patterns conforming to the reported water circulation in the bay. The maximum concentration was found near Todos Santos Canyon. The largest concentrations found were those of fluoranthene (120.6 ng/g), Indene(1,2,3-c,d)pyrene (115.6 ng/g) and pyrene (109.9 ng/g). Percentagewise, the main components were PAHs with three and four rings. Several indexes were used to investigate origins including simple PAH ratios and ternary plots. These indexes and plots suggest the main origin as a combination of urban air and wood and brush fires with little influence of oil.

Heavy metals in the fine fraction of coastal sediments from Baja California (Mexico) and California (USA).

The concentrations of heavy metals in the fine fraction (<63 microm) of 19 surficial sediment samples from the border region of Baja California (Mexico) and California (USA) were determined. The concentration ranges (in microg g(-1)) of the metals were: Cu, 4.9-23; Zn, 39-188; Ni, 16-44; Cr, 56-802; Pb, 6-21; Cd, 0.08-0.64; Ag, 0.01-0.28; and Mn, 392-1506; the intervals (percentage) for Fe and Al were 1.36-4.6 and 3.61-8.55, respectively. The heavy metals in these sediments indicate a relative enrichment of Cr (>3000%), Zn (>350%), Ni (>300%) and Cu (>150%) off the wastewater outfall at Punta Bandera in Tijuana, Baja California, with respect to non-polluted sediments of the region. Pb, Cd and Ag have low concentrations off the same outfall and enrichment factors are generally lower than 300% (Pb) and lower than 150% (Cd and Ag). This suggests that these metals have a different origin, or that they are controlled by a different geochemical mechanism than the former. The concentrations of Mn, Fe and Al occurred within ranges typical for coastal areas and probably reflect the mineralogical composition of the sediments of the region.

The metabolism of gluconate in Escherichia coli. The subsidiary system and the nature of the gntS gene.

The transport and phosphorylation of gluconate in E. coli occurs through two systems (GntI and GntII) which duplicate activities. bioH-asd deletion mutants do not grow on media with gluconate as sole carbon source because they lack the GntI system and do not express GntII. Although E. coli c177 is a delta (bioH-asd) mutant, it carries the pyrB linked mutation gnt177 that enables it to metabolize this substrate through inducible expression of the GntII system. Several gntS derivatives which are unable to grow on gluconate were isolated from E. coli C177 by spontaneous curing of the transposon Tn10 previously inserted at the gntS locus (zjf::Tn10, min 95.3). A representative gntS mutant, E. coli TI141A retained the ability to take up gluconate but had lost the thermosensitive gluconokinase activity (gene gntV, min 96.9). Furthermore, it could be demonstrated that gntV is repressed in E. coli TI141A. The results indicate that gntS might specify a trans-acting positive regulator involved in the control of at least the expression of the thermosensitive gluconokinase (GntII), instead of a gluconate uptake system as it was previously postulated. Likewise, these results can be used to reconsider whether the locus altered by the gnt177 lesion is allelic with that of the GntII permease instead of a regulator, as it was originally postulated.