Biotechnological production of poly(3-hydroxybutyrate) with Wautersia eutropha by application of green grass juice and silage juice as additional complex substrates

Alternative inexpensive complex nitrogen- and phosphate sources from agriculture, green grass juice (GGJ) and silage juice (SJ), were added to cultivation medium in order to investigate their impact on growth of the well-known polyhydroxyalkanoate (PHA) accumulating strain Wautersia eutropha. The influence of these additives was directly compared with cultivations on defined minimal mineral medium (M) as well as on the same medium supplemented with more expensive complex additives: corn steep liquor (CSL) and casamino acids (CA). It turned out that the supplementation with most complex additives results in shortening of lag-phases of bacterial growth and in higher end-concentrations of residual biomass compared with M-medium. Finally, higher volumetric productivities for poly(3-hydroxybutyrate) (3-PHB) were achieved. The effect of the inexpensive additive SJ on volumetric productivity was similar to the result for the expensive CA (0.653 vs. 0.619 g L^-1 h^-1). The same was found for the biomass concentration (7.00 vs. 7.44 g L^-1 respectively). Together with an economic appraisal presented in this study, the results suggest it is possible to make the sustainable process of microbial PHA-production more economically feasible. A survey of the thermal characteristics and molecular mass properties of the isolated polymers completes this work.     

Roller Coaster Behavior in the Cruziana Rugosa Group from Penha Garcia (Portugal): Implications for the Feeding Program of Trilobites

Trilobite burrows of the Cruziana rugosa group are common and well preserved in the Armorican Quartzite Formation (Lower to Middle Ordovician) of the Ponsul River gorge in Penha Garcia. Based on morphological and behavioral peculiarities, Cruziana beirensis is reinstated herein and included in the rugosa group. Apart from the broad range in morphology and size, Cruziana from Penha Garcia show higher behavioral diversity using food sources than has ever been documented in a single section. This behavioral diversity, mainly in circling behavior, has been analyzed using the Capacity Fractal Dimension by implementation of the box-counting theorem applied to the bedding plane. Fractal Dimension also suggests that Cruziana rouaulti can be included in the rugosa group, despite the obscurity of the scratch patterns, as products of juveniles. Circling, sinusoidal or teichichnoid behavior modifications reflect a generalist mode of sediment feeding, claimed mudtrophobacterivory, while most of the interactions with worm burrows originated previously or (mostly) later, by interpreted trilobite necrophagy and/or worm commensalism. Patchy exploitation of biomat grazing fields is inferred from Cruziana preservation styles, physical interactions with biomat-related sedimentary structures and area-limited high bioturbational indices in the explored tier.