| A lot of Keratinaceous materials are released in China, but they have not been used properly. Keratinaceous materials would become a good resource if processed with microorganisms. In order to exploit the resource, it is necessary to achieve some microbial strains with high activity, develop a new process for Keratin hydrolysis and design a tailor-made equipment for the reaction.The reuse of feather wastes was studied during the last three years and the following achievements were gained:1 . Eight microbial strains with high activity for feather-degradation were isolated from the activated sludge of a wastewater treatment plant on a farm for animal husbandry. Among them, two strains were identified as actinomycetes (A1 and A2), three strains were identified as fungi (F1, F2 and F3) and three strains were identified as bacteria (B1, B2 and B3). All these microorganisms were able to degrade feather efficiently, and stain A1 and strain F1 showed the highest activity. Both strain A1 and strain F1 could grow on feathers as the sole carbon, nitrogen and energy sources. The whole feathers pretreated by autoclaving would disappear in the culture of strain A1 or strain F1 in 4~5 days.2. The characteristics of strain F1 were further studied. Strain F1 grew fast with a colony of 3 centimeters in diameter after cultivated on PSA (potato-sucrose agar) at 28癈 for 10 days. The colony was odorless and its surface looked powdery and white to pink. The back of colony was purple. Hyphae were 2-3um in diameter with regular septa and plurinuclear. It was characterized by macronematous penicillate conidiophores, and the divergent phialides consisted of a swollen base tapering into a rather long and slender neck. Conidia were in chain, smooth-walled, ellipse. Sexual propagation was unknown. So strain F1 was identified as Paecilomyces Bain. Paecilomyces isfound for the first time to be able to degrade feather.3. The growth conditions of strain F1 and strain A1 were tested. They were both aerobe and their activity was stimulated by Ca2+ and Mg2+. As for strain F1, the pH and temperature optima were determined to be 9 and 30 C, respectively. As for strain A1, the pH and temperature optima were 8 and 35-40 C, separately.4. The feather-degrading kinetic equations of strain F1 and strain A1 were established. It was proved that both degrading processes could be expressedby Briggs-Haldane equation When the concentration of feather was high (in the initial stage of the reaction), strain F1 was a better choice for its greater reaction potential. But in the latter stage of the reaction, when feather concentration was low, strain A1 was a better choice for its greater affinity. Because the reaction rate was the primary factor to determine economic cost, strain F1 was a better choice for exploitation than strain A1 .5. A new process of feather-biodegradation by microorganisms was put forward. Feathers were firstly washed with water prior to autoclaving, then hydrolyzed in tailor-made equipment. Soluble proteins were reclaimed from hydrolyzate and feedstuffs of high protein were produced from hydrolytic residues at last. 0.11kg soluble protein and 0.6kg feedstuff of high protein could be reclaimed from 1 kg feather wastes by this process.6. High-efficiency hydrolytic equipment for feather-keratin was created and studied. Feather leaching bed was designed with garbage compost and active bio-filter equipments for reference. Feathers pretreated by autoclaving were used for "packing materials" and put in the middle of the bed on whichmicroorganisms grew. Inorganic culture media were sprayed on the "packing materials" from the top and hydrolyzate with large content of soluble proteins was led off from the bottom. Its operating and efficient parameters were as follows: airflow rate (1195.2m3/m3-d), influent flow rate (0.3m3/m3-d), return flow rate (6.72m3/m3-d), volumetric loading rate (6.67kg/m3-d), conversion percentage (40%), volumetric soluble protein production rate (2.4kg/m3-d).
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