A bacterium belonging to the Bacillus firmus/lentus-complex and capable of growth on native potato starch was isolated from sludge of a pilot plant unit for potato-starch production. Utilization of a crude enzyme preparation obtained from the culture fluid after growth of the microorganism on native starch, resulted in complete degradation of native starch granules from potato, maize and wheat at a temperature of 37°C. Glucose was found as a major product. Production of maltose, maltotriose and maltotetraose was also observed. Native-starch-degrading activity (NSDA) could be selectively adsorbed on potato-starch granules, whereas soluble-starch-degrading activity (SSDA) remained mainly in solution. The use of such a starch-adsorbed enzyme preparation on native starch resulted in a completely changed product pattern. An increase in oligosaccharides concomitant with less glucose formation was observed. An increased conversion of soluble starch to maltopentaose was possible with this starch-adsorbed enzyme preparation. It is concluded that NSDA comes from α-amylase(s) and SSDA from glucoamylase(s) and/or α-glucosidase(s). Cultivation of B. firmus/lentus on glucose, maltose, or soluble starch resulted in substantially smaller quantities of (native) starch-degrading activity.
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The increasing demand for Prunus africana resources is an opportunity for its conservation and commercial use to support livelihoods in Africa. The objective for this study was to investigate major steps to advance production of P. africana for long-term commercial use in Uganda. Specific objectives were to explore potential production schemes, setbacks in production and strategies to advance it. The study was done by review of literature, documents and interviews with experts. Results indicated Agroforestry and large plantations to be useful schemes for production. Identified setbacks are: low trade in P. africana, unknown returns from production, competing land uses, long growth period, limited market assurance and information. The lack of a resource assessment for P. africana in forests contributes to its low trade which undermines related economic benefits for national development and incentives to commercial production. We propose that a national Quantitative resource assessment of P. africana in forests is one of the crucial steps that should be undertaken to carefully organise and advance sustainable trade to provide rational incentives for commercial production. Subsequently, production should be localised in suitable sites and producers be organised into cooperatives. Further research to improve returns from commercial production of P. africana is needed.
MULTIFILE
Worldwide, an increasing number of students seek private supplementary tutoring, known as ‘shadow education.’ Various studies report social class differences in the use of shadow education. High-SES families may invest in shadow education as a form of concerted cultivation, seeking to improve their children’s school achievement. In this study, we apply meta-analytic structural equation modeling to explore relationships between parental education, income, and the use of shadow education across nations and educational contexts. We find robust relationships between parental education, income and the use of shadow education. Moreover, we assess a mediating role of shadow education in the relationship between SES and achievement. Shadow education appears to fulfill a competitive function for privileged families who seek to secure advantage in educational competition. We conclude that educational research, particularly research concerned with inequality of opportunities, needs to take account of the progressively prominent position of shadow education in the educational landscape.
The denim industry faces many complex sustainability challenges and has been especially criticized for its polluting and hazardous production practices. Reducing resource use of water, chemicals and energy and changing denim production practices calls for collaboration between various stakeholders, including competing denim brands. There is great benefit in combining denim brands’ resources and knowledge so that commonly defined standards and benchmarks are developed and realized on a scale that matters. Collaboration however, and especially between competitors, is highly complex and prone to fail. This project brings leading denim brands together to collectively take initial steps towards improving the ecological sustainability impact of denim production, particularly by establishing measurements, benchmarks and standards for resource use (e.g. chemicals, water, energy) and creating best practices for effective collaboration. The central research question of our project is: How do denim brands effectively collaborate together to create common, industry standards on resource use and benchmarks for improved ecological sustainability in denim production? To answer this question, we will use a mixed-method, action research approach. The project’s research setting is the Amsterdam Metropolitan Area (MRA), which has a strong denim cluster and is home to many international denim brands and start-ups.
The seaweed aquaculture sector, aimed at cultivation of macroalgal biomass to be converted into commercial applications, can be placed within a sustainable and circular economy framework. This bio-based sector has the potential to aid the European Union meet multiple EU Bioeconomy Strategy, EU Green Deal and Blue Growth Strategy objectives. Seaweeds play a crucial ecological role within the marine environment and provide several ecosystem services, from the take up of excess nutrients from surrounding seawater to oxygen production and potentially carbon sequestration. Sea lettuce, Ulva spp., is a green seaweed, growing wild in the Atlantic Ocean and North Sea. Sea lettuce has a high nutritional value and is a promising source for food, animal feed, cosmetics and more. Sea lettuce, when produced in controlled conditions like aquaculture, can supplement our diet with healthy and safe proteins, fibres and vitamins. However, at this moment, Sea lettuce is hardly exploited as resource because of its unfamiliarity but also lack of knowledge about its growth cycle, its interaction with microbiota and eventually, possible applications. Even, it is unknown which Ulva species are available for aquaculture (algaculture) and how these species can contribute to a sustainable aquaculture biomass production. The AQULVA project aims to investigate which Ulva species are available in the North Sea and Wadden Sea which can be utilised in onshore aquaculture production. Modern genomic, microbiomic and metabolomic profiling techniques alongside ecophysiological production research must reveal suitable Ulva selections with high nutritional value for sustainable onshore biomass production. Selected Ulva spp lines will be used for production of healthy and safe foods, anti-aging cosmetics and added value animal feed supplements for dairy farming. This applied research is in cooperation with a network of SME’s, Research Institutes and Universities of Applied Science and is liaised with EU initiatives like the EU-COST action “SeaWheat”.
Sea Lettuce, Ulva spp. is a versatile and edible green seaweed. Ulva spp is high in protein, carbohydrates and lipids (respectively 7%-33%; 33%-62% and 1%-3% on dry weight base [1, 2]) but variation in these components is high. Ulva has the potential to produce up to 45 tons DM/ha/year but 15 tons DM/ha/year is more realistic.[3, 4] This makes Ulva a possible valuable resource for food and other applications. Sea Lettuce is either harvested wild or cultivated in onshore land based aquaculture systems. Ulva onshore aquaculture is at present implemented only on a few locations in Europe on commercial scale because of limited knowledge about Ulva biology and its optimal cultivation systems but also because of its unfamiliarity to businesses and consumers. The objective of this project is to improve Ulva onshore aquaculture by selecting Ulva seed material, optimizing growth and biomass production by applying ecophysiological strategies for nutrient, temperature, microbiome and light management, by optimizing pond systems eg. attached versus free floating production and eventually protoype product development for feed, food and cosmetics.
