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231.
In vitro antioxidant and anti-inflammatory activities of fluidized bed ethanol extracts of Pleurotus ostreatus PQMZ91109, PBS281009, M2191 (obtained from a laboratory greenhouse), Agaricus bisporus, Marasmius oreades, Craterellus cornucopioides, and Tuber melanosporum were investigated using free radical scavenging activities, metal chelating effects, inhibition of lipid peroxidation (inhibition of peroxyl radicals), xanthine oxidase, and lipoxygenase, and identification of antioxidant compounds. Levels of different compounds with antioxidant properties demonstrated the presence of more tocopherols than polyphenol carboxylic acids and flavones. HPLC showed that T. melanosporum extracts had high correlation values between levels of different active compounds and antioxidant assay results. Tocopherol levels were highly correlated (R 2=0.867) with anti-inflammatory activities and inhibition of lipid peroxidation. Fluidized bed ethanol extracts from dried mushroom fruit bodies can be a source of products rich in tocopherols, and can constitute an important ingredient in food supplements. 相似文献
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233.
The success of crowdsourcing (CS) systems depends on sustained participation, which is an ongoing challenge for the majority of CS providers. Unfortunately, participants are frequently demotivated by technical difficulties and the incorrect use of CS systems, which can result in CS failure. Although the literature generally assumes that sustained participation in CS is determined by a shift between intrinsic and extrinsic motivation, the role of system-use practices in facilitating such a shift remains unknown. We explore how CS system-use practices influence participants' sustained motivation, evolving from initiation to progression to sustention. Using the notion of technology-in-practice as a lens, we develop and examine a process model using an in-depth case study of a large-scale ongoing CS project, the Australian Newspaper Digitisation Program. The findings suggest that CS participants' motivation is shaped by an evolving combination of three basic components (i.e., contextual condition, outcome and action intensity) and mediated by two types of system-use practice (i.e., passive and active). Passive-use practices facilitate sustaining motivation from initiation to progression, whereas active-use practices have a key role in sustention. Our study contributes to the emerging literature on the substantial role of system-use practices in sustaining motivation, resulting in sustained participation. The findings also offer actionable insights into improving the viability of CS systems in retaining and motivating continuous and increased contributions from participants. 相似文献