Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2024
Authors
Abirami Ramu Ganesan Kannan Mohan Sabariswaran Kandasamy Ramya Preethi Surendran Ragavendhar Kumar Durairaj Karthick Rajan Jayakumar RajarajeswaranAbstract
Black Soldier Fly (Hermetia illucens [L.], Diptera: Stratiomyidae) larvae (BSFL) production from food waste is gaining interest. Food waste, a heterogeneous mix of agro-food and catering leftovers serves as a challenging feedstock for BSF growth due to its varying nutrient composition. BSF, are classified as polyphagous insects with a digestive system featuring midgut for digestion and nutrient absorption. The conversion of food waste by BSFL is heavily influenced by Enterococcus, Klebsiella, Morganella, Providencia, and Scrofimicrobium, which play a vital role in substrate utilization. These microbes determine growth patterns, longevity, oviposition, and egg hatchability, which are intricately tied to the sugar and protein content of their dietary substrates. Pre-treatment techniques including hydrothermal treatment, ionization, pulse electric field discharge, and microbial treatment showed better efficiency in improving the wet waste biomass surface area and waste recovery ratio. In terms of environmental sustainability, a life cycle assessment (LCA) of food waste to BSF conversion facility yields a low global warming potential (GWP) score of 17.36 kg CO2 per ton of functional unit with a significant environmental impact during pre-treatment of food waste at a mass-rearing of BSFL. Therefore, this review emphasizes the digestive system, and gut microbiota of BSFL, with food waste-nutrient utilization by the BSFL. Environmentally promising steps involved in the valorization of food waste resources were evaluated in detail. This review also covers the international regulations involved in food waste fed BSFL, and techno-economic assessment to optimize its valuable nutrients for the new economy in waste management with less environmental footprint.
Abstract
No abstract has been registered
Authors
Abirami Ramu GanesanAbstract
Horticultural food waste can be recovered to produce high-value products. Appropriate green solvents and a selection of cleaner production could unlock waste into useful resources for human health. This will significantly reduce greenhouse gas emissions, and CO2 production, and create economic opportunities to contribute to food security.
Abstract
The brown marine macroalga Alaria esculenta contains phlorotannins as polyphenolic compounds in its cell walls. This study aimed to understand their antioxidant effects on preserving the lipids in fillets of freshly-slaughtered farmed Atlantic salmon (Salmo salar). First, soluble phlorotannins were extracted from wild-grown population of A. esculenta in North Norway (Bodø) using solid/liquid extraction. A small-scale solid/liquid extraction (15 mg mL−1) with 70% acetone showed that 84% of total soluble phlorotannins (25.10 mg g−1 dry weight) were extracted after the first out of four extraction steps. In a large-scale extraction (3 mg 400 mL−1), the contents of soluble phlorotannins and the DPPH-based antioxidant capacities (measured as IC50) in 70% acetone- and water-based crude extracts were similar. Water is preferred extraction solvent for the following experiment because it complies with food safety standards, may minimise work procedures and is in accordance with the principles of Green Chemistry. Secondly, the antioxidant properties of the soluble phlorotannins were tested through incubating salmon fillets (Norwegian Quality Cuts) in water-based extracts. After six days of storage on ice, the peroxide value of Alaria-treated fillets was lower compared to the control (without Alaria-extract), while the p-anisidine and free fatty acid values remained unchanged. This indicates the phlorotannins’ inhibitory effect on the formation of primary rather than secondary lipid oxidation products. This study demonstrated that the antioxidant properties of the soluble phlorotannins extracted from A. esculenta using water can preserve the nutritional value of salmon fillets to extend the seafood’s shelf-life.
Authors
Ralf RautenbergerAbstract
During the cultivation of Ulva fenestrata in a land-based aquaculture system, the colonisation of the water tanks’ surfaces and eventually the macroalgal biomass by the biofouling diatom Fragilariopsis oceanica compromises the production process. Since germanium dioxide (GeO2) is an effective growth inhibitor of diatoms, this study aimed to understand how it affects the presence of F. oceanica and the photosynthesis and growth of U. fenestrata as a primary parameter contribution to the biomass production. A toxicological dose-response experiment showed that the diatom’s growth was inhibited at the low GeO2 concentration of 0.014 mg l−1. In contrast, the photosynthetic performances and growth rates of U. fenestrata remained unaffected under a wide GeO2 concentration range (0.022–2.235 mg l−1) in small- and large-scale experiments in 1-l glass beakers and 100-l Plexiglass water tanks, respectively. In the latter, the diatom density in the tanks was reduced by 40 %. The costs arising from the use of GeO2 can range between €2.35 and €8.35 kg−1 fresh weight of produced U. fenestrata biomass under growth conditions resulting in growth rates of 20 and 11.5 % d−1, respectively. GeO2 is an effective agent to control biofouling diatoms such as F. oceanica during the land-based biomass production of U. fenestrata.
Abstract
Eutrophication of coastal ecosystems often stimulates massive and uncontrolled growth of green macroalgae, causing serious ecological problems. These green tides are frequently exposed to light intensities that can reduce their growth via the production of reactive oxygen species (ROS). To understand the physiological and biochemical mechanisms leading to the formation and maintenance of green tides, the interaction between inorganic nitrogen (Ni) and light was studied. In a bi-factorial physiological experiment simulating eutrophication under different light levels, the bloom-forming green macroalga Ulva rigida was exposed to a combination of ecologically relevant nitrate concentrations (3.8–44.7 µM) and light intensities (50–1100 µmol photons m−2 s−1) over three days. Although artificial eutrophication (≥ 21.7 µM) stimulated nitrate reductase activity, which regulated both nitrate uptake and vacuolar storage by a feedback mechanism, nitrogen assimilation remained constant. Growth was solely controlled by the light intensity because U. rigida was Ni-replete under oligotrophic conditions (3.8 µM), which requires an effective photoprotective mechanism. Fast declining Fv/Fm and non-photochemical quenching (NPQ) under excess light indicate that the combined photoinhibitory and PSII-reaction centre quenching avoided ROS production effectively. Thus, these mechanisms seem to be key to maintaining high photosynthetic activities and growth rates without producing ROS. Nevertheless, these photoprotective mechanisms allowed U. rigida to thrive under the contrasting experimental conditions with high daily growth rates (12–20%). This study helps understand the physiological mechanisms facilitating the formation and persistence of ecologically problematic green tides in coastal areas.
Authors
Ralf RautenbergerAbstract
No abstract has been registered
Authors
João Neiva Jorge Manuel Ferreira de Assis Eliza Fragkopoulou Gareth A. Pearson Peter T. Raimondi Laura Anderson Dorte Krause-Jensen Núria Marbà Andrew Want Olga Selivanova Masahiro Nakaoka W. Stewart Grant Brenda Konar Michael Roleda Mikael K. Sejr Cristina Paulino Ester A. SerrãoAbstract
Amphiboreal taxa are often composed of vicariant phylogroups and species complexes whose divergence and phylogeographic affinities reflect a shared history of chronic isolation and episodic trans-Arctic dispersal. Ecological filters and shifting selective pressures may also promote selective sweeps, niche shifts and ecological speciation during colonization, but these are seldom considered at biogeographical scales. Here we integrate genetic data and Ecologic Niche Models (ENMs) to investigate the historical biogeography and cohesion of the polymorphic rockweed Fucus distichus throughout its immense amphiboreal range, focusing on trans-Arctic asymmetries, glacial/interglacial dynamics, and integrity of sympatric eco-morphotypes. Populations were sampled throughout the Pacific and the Atlantic, from southern rear-edges to the high-Arctic. They were genotyped for seven microsatellites and an mtDNA spacer, and genetic diversity and structure were assessed from global to local scales. ENMs were used to compare niche divergence and magnitude of post-glacial range shifts in Pacific versus Atlantic sub-ranges. Haplotypic and genotypic data revealed distinct and seemingly isolated Pacific vs Arctic/Atlantic gene-pools, with finer-scale regional sub-structuring pervasive in the Pacific. MtDNA diversity was highly structured and overwhelmingly concentrated in the Pacific. Regionally, Alaska showed the highest intra-population diversity but the lowest levels of endemism. Some sympatric/parapatric ecotypes exhibited distinct genotypic/haplotypic compositions. Strikingly, niche models revealed higher Pacific tolerance to maximum temperatures and predicted a much more consolidated presence in the NE Atlantic. Glacial and modern ranges overlapped extensively in the Pacific, whereas the modern Atlantic range was largely glaciated or emerged during the Last Glacial Maximum. Higher genetic and ecogeographic diversity supports a primary Pacific diversification and secondary Atlantic colonization, also likely reflecting the much larger and more stable climatic refugia in the Pacific. The relic distribution and reduced ecological/morphological plasticity in the NE Atlantic are hypothesized to reflect functional trans-Arctic bottlenecks, recent colonization or competition with congeners. Within the Pacific, Alaska showed signatures of a post-glacial melting pot of eastern and southern populations. Genetic/ecotypic variation was generally not sufficiently discontinuous or consistent to justify recognizing multiple taxonomic entities, but support a separate species in the eastern Pacific, at the southern rear-edge. We predict that layered patterns of phylogeographic structure, incipient speciation and niche differences might be common among widespread low-dispersal amphiboreal taxa.
Authors
Ralf Rautenberger Alexandre Detain Kari Skjånes Peter Simon Claus Schulze Viswanath Kiron Daniela Morales-SánchezAbstract
No abstract has been registered
Abstract
No abstract has been registered