The anthropologic impact on climate has reached severe heights since humanity is still holding onto non-renewable fossil sources. Lignins can play a key role in the transition from petroleum based...

Ludwigia peruviana is an aquatic shrubby species introduced from the Americas and spreading to wetlands in coastal south-eastem Australia. It has become dominant, replacing much of the former vegetation in the Botany Wetlands, a series of shallow urban swamps and lakes near Sydney, Australia. Studies of L. peruviana were essential to the development of a management plan for the Botany Wetlands. Ecological studies were conducted in situ and supplemented by a series of germination and growth experiments in controlled environments. Flowering peaked in early autumn. Seed production for 1990-91 was -450000 seeds m-2 and there was also -65000 seeds m-2 in the soil seed bank and -300000 seeds m-2 in old fruits that remained on the stems over winter. The seeds are -0.8 mm long, weigh -0.05 mg, are hydrophobic, usually germinate while afloat, and are easily dispersed by water, machinery and birds. Viability of fresh seed was 99% (tetrazolium dye test), and -20% of seeds were dormant. Dormancy appeared to break down within two years. Propagation and dispersal may also occur by means of stem pieces that produce new shoots. New plants from seed, seedlings or stem fragments may become established on strand lines or form floating islands that may eventually become stranded. Management needs to focus on control of the seedlings and soil seed bank.

Lignin is a promising biopolymer to serve as a sustainable resource for a multitude of applications (e.g., thermoset materials, production of bulk chemicals) thereby substituting fossil-based carbon sources. In this work, the reductive depolymerization of Kraft lignin (KL) was studied in ethanol/water aided by formic acid (FA) as the way forward to valorize lignin. The effect of various process conditions was elucidated using 31 P-NMR, pH, GPC, CHNSO, GC-MS and 2D-LC analyses. It is found that the addition of a small amount of FA (3.6 vol%) is beneficial for obtaining smaller lignin fragments with more phenolic OH (PhOH) functionalities upon depolymerization at 250°C for 8h. Besides, a higher FA concentration causes acid catalyzed lignin repolymerization and a longer reaction time results in only a limited reduction in molecular weight of the obtained lignin fragments. The addition of a supported Pd catalyst leads to a more pronounced depolymerization (smaller lignin fragments with more PhOH functionalities) as well as a stronger decrease in oxygen and sulfur content. Furthermore, several experiments and multiple analysis techniques support the hypothesis that FA acts as H2 donor under the investigated conditions in this study. In conclusion, KL (MW ~16436 g mol -1 and 3.31 mmol g -1 PhOH) was successfully depolymerized into a low molecular weight lignin (MW ~3250 g mol -1 ) with more PhOH functionalities (5.29 mmol g -1 ).

We describe Malawidopsis gen. nov., a new genus of Cypridopsinae Kaufmann, 1900 from the African ancient Lake Malawi.                 The genus comprises at least 17 new species, which makes it a significant ostracod radiation in this lake, parallel to a similar (but independent) cypridopsine radiation in Lake Tanganyika. Three of these new species are here described: Malawidopsis stellae gen. et. sp. nov., the type species of the new genus; M. ruwaydae gen. et. sp. nov. and M. antoniae gen. et. sp. nov.. The other new species are briefly illustrated and described, but are left in open nomenclature (sp. A, B, C, etc.). Cypridopsis cunningtoni Sars, 1910 and Potamocypris fuelleborni Daday, 1910 are transferred to Malawidopsis gen. nov. and are identical to Malawidopsis spec. F and Malawidopsis spec. N, respectively.                 The new tribe Plesiocyprisopsini trib. nov. is erected, and comprises the cypridopsine genera previously in the Cypridopsini s.l. with the right valve overlapping the left valve, at least anteriorly.                 Potential drivers of speciation within this endemic clade in Lake Malawi are briefly discussed. Bathymetry might have been important, with most species being restricted to shallower depths and only four species also occurring at depths of 75 m or more, but very few specimens were retrieved from greater depths. Most species occurred on coarse sand, but this sediment category coincides with shallower stations. Overall, most species appear to have a wide geographical distribution in the lake, so no geographical parapatric speciation is apparent. The occurrence of all species in sexual populations and the significant differences in the male sexual organs and the valves suggest that sexual selection might have been the most important driver in the speciation process of this species flock, but this should be further explored. Following deep coring results in Lake Malawi, the present clade could be (at least) c one million years old.

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Bacillus cereus is a spore-forming bacterium that occurs as a contaminant in food and feed, occasionally resulting in food poisoning through the production of various toxins. In this study, we retrospectively characterized viable B. cereus sensu lato (s.l.) isolates originating from commercial vitamin B2 feed and food additives collected between 2016 and 2022 by the Belgian Federal Agency for the Safety of the Food Chain from products sold on the Belgian market. In total, 75 collected product samples were cultured on a general medium and, in case of bacterial growth, two isolates per product sample were collected and characterized using whole-genome sequencing (WGS) and subsequently characterized in terms of sequence type (ST), virulence gene profile, antimicrobial resistance (AMR) gene profile, plasmid content, and phylogenomic relationships. Viable B. cereus was identified in 18 of the 75 (24%) tested products, resulting in 36 WGS datasets, which were classified into eleven different STs, with ST165 (n = 10) and ST32 (n = 8) being the most common. All isolates carried multiple genes encoding virulence factors, including cytotoxin K-2 (52.78%) and cereulide (22.22%). Most isolates were predicted to be resistant to beta-lactam antibiotics (100%) and fosfomycin (88.89%), and a subset was predicted to be resistant to streptothricin (30.56%). Phylogenomic analysis revealed that some isolates obtained from different products were closely related or even identical indicating a likely common origin, whereas for some products the two isolates obtained did not show any close relationship to each other or other isolates found in other products. This study reveals that potentially pathogenic and drug-resistant B. cereus s.l. can be present in food and feed vitamin B2 additives that are commercially available, and that more research is warranted to assess whether their presence in these types of products poses a threat to consumers.