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91.
Arylsulfatase-C and sterol sulfatase were thought to be identical enzymes whose X-linked locus escapes inactivation. However, recent evidence shows that they are not identical but that arylsulfatase-C in human fibroblasts exists in two isozymic forms, designated as slow and fast. We now report that the two forms are enzymatically different. When assayed with an artificial fluorogenic substrate, the slow form showed a pH optimum of 8.00 and a Km of 228 microM. In contrast, the fast form showed a pH optimum of 7.67 and a Km of 86.7 microM with substrate inhibition occurring above 0.33 mM. The heat stability of the fast form was slightly below that of the slow form. Polyclonal antibodies raised against the slow form did not cross-react with the fast form. Hence, the two isozymic forms of arylsulfatase-C are enzymatically and structurally different and the slow form is associated with sterol sulfatase activity.  相似文献   
92.
Bioprocess and Biosystems Engineering - In this study, laccase was immobilized on nylon 6,6/Fe3+ composite (NFC) nanofibrous membrane and used for the detoxification of...  相似文献   
93.
  • The taxonomic importance of macromorphological and micromorphological seed characteristics was investigated using SEM of ten species of the Salvia genus from Pakistan. The aim was to identify diagnostic seed ultrastructural features that could aid in species delimitation, correct identification and phylogenetic position. The ultrastructure of Salvia varies greatly, and a wide range of unique micromorphological features have been observed.
  • Seed micromorphological features were explored by SEM, including seed shape, colour, texture, cell outline, surface sculpturing, epidermal cell arrangement, anticlinal, and periclinal wall pattern.
  • Seed shapes were categorized as obovate, spherical, spheroid, broadly elliptic, elliptic and oblong, mostly with a terminal hilum. Seed colours were black, light brown, dark brown, brown and yellow. Exo-morphological characters, i.e. epidermal cell arrangements, included irregular, wavy pentagonal-hexagonal, regular pentagonal-hexagonal. Cluster analysis was used to assess similar and distinct species within Salvia with a feasible explanation. Taxonomic keys were made based on micromorphological qualitative features that help to delimit species and identify them quickly within the Salvia genus.
  • Seed morphology of ten Salvia species was described and investigated, and the diagnostic significance of features evaluated using SEM. This study analysed seed features, especially at the species level, which might provide much new taxonomic information. The results revealed that, in seed morphology, using SEM can help with taxon identification, especially at the genus and species levels.
  相似文献   
94.
Solid waste management is a serious ecological problem in Saudi Arabia due to rapid industrialization, population growth and urbanization. Recycling and sorting are in their infancy in Saudi Arabia and huge amounts of mixed household and industrial wastes are still dumped without any pre-treatment. Solid waste management techniques such as incineration, pyrolysis and gasification have high investment costs. Composting and vermicomposting of solid organic waste have been considered as an economically viable and sustainable waste management technologies. However, wastes often contain pollutants, such as heavy metals that are toxic to decomposer micro-organisms. Thus, heavy metals are a challenge for the successful biological treatments. Waste may also contain a mixture of organic pollutants that certain microbes, such as micro-algae are known to degrade. The present review paper focuses on understanding the role of vermicomposting as a management tool in mitigating solid organic wastes. It is noteworthy to mention that the microbes also play a pivotal role in the degradation process, wherein the enzymes secreted during the process aid in decomposition of complex molecules into simpler compounds. Also, the extracellular polymeric substance secreted by the earthworm under metal stress serves a source of nutrient for the bacteria to flourish. Henceforth the goal of discussion in present review shows the way forward in using vermicomposting as a novel approach in dealing with solid organic waste.  相似文献   
95.
96.
Al-Hassa oasis is considered as the biggest irrigated one in the World, being well known for its extensive date palm cultivation with an estimate of at least three million trees. The aim of this study is to evaluate the impact of soil fertilization practices on the productivity potential of date palm trees grown under the climatic conditions of Al-Hassa oasis, KSA. The opinions of 258 active farmers were randomly surveyed using specifically designed questioners that were also fortified with personal communications. The size of the samples was designated in accordance to Cocoran equation. The total samples were allocated into two major parts (193 for the old oasis and 65 for the new oasis). Results showed that the farm features (utilized agricultural area (UAA), ownership and labors) are different in both parts of the oasis. Fertilization practices (quantity applied per area or per tree) were diverse causing dissimilar productivity potentials (total or per area or tree). The average production of a tree in the old oasis is 81.4 kg, whilst it is 54.6 kg in the new oasis. Date palm production is significantly affected by total number of trees, applied fertilizer quantity, cultivated area and labor power. The impact of these factors is unlike between the two parts of the oasis. It is then concluded from the study that there are sincere needs for improving the soil fertilization practiced for the date palm trees grown in the Al-Hassa oasis, KSA in order to increase their productivity potential and hence improve the farmers' income.  相似文献   
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