The rational use of natural resources, including the creation of new and improvement of existing technologies in order to reduce the anthropogenic impact on the environment, is currently an important task. This review covers different methods of softwood bark processing. Bark is used for the production of heat-insulating plates, and also as filler in adhesives and composites. In agriculture, it is used as a mulch. Softwood bark is a valuable raw material for chemical processing. Extractive substances of the bark are of particular interest. Among them, phenolic compounds are very important, in particular of tannin nature, which are used as tanning agents in leather production. Bark is used for the isolation of substances with antibacterial activity for pharmaceutical and nutraceutical applications. Aqueous-alkaline solutions, in particular monoethanolamine, are used as an extracting agent. Currently, tannins have been applied into many different fields, including medicine, food, beverage, the manufacture of ink and adhesives, the dye and tanning industry, plastic resins, water purification, and surface coatings. Tanning extracts obtained as a result of extraction are refined by ultrafiltration. The obtained extracts are of high purity. The extraction residue, the so-called tan, is a promising raw material for obtaining a cellulosic product. In addition to the chemical conversion of tan, biotechnological processing is an alternative option. In the process of tan biodegradation by the microscopic Trichoderma fungus, a biological product trichodermin is obtained, which is used to protect plants from phytopathogens.
Abstract-The effects of commercial fi shing with crab pots on the physical condition of the snow crab (Chionoecetes opilio) and southern Tanner crab (C. bairdi) were investigated in the Bering Sea and in Russian waters of the Sea of Okhotsk. In crabs that were subjected to pot hauling, the presence of gas embolism and the deformation of gill lamellae were found in histopathological investigations. Crab vitality, which was characterized subjectively through observation of behavioral responses, depended on not only the number of pot hauls but also the time between hauls. Immediately after repeated pot hauls at short time intervals (≤3 days), we observed a rapid decline in vitality of crabs. When hauling intervals were increased to >3 days, the condition of crabs did not significantly change. After repeated pot hauls, concentration of the respiratory pigment hemocyanin ([Hc]) was often lower in the hemolymph of crabs than in the hemolymph of freshly caught animals. Our research indicated that changes in [Hc] in crabs after repeated pot hauls were caused by the effects of decompression and not by starvation of crabs in pots or exposure of crabs to air. We suggest that the decrease in [Hc]
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