Protein powders from Eisenia foetida were prepared using different drying processes and fractionation. Differential scanning calorimetry was used to show that heat denaturation occurred during the drying process above...Protein powders from Eisenia foetida were prepared using different drying processes and fractionation. Differential scanning calorimetry was used to show that heat denaturation occurred during the drying process above 42°C. Protein solubility was also studied. The addition of dissociating reagents allowed concluding that solubility was decreased during oven drying due to thermo denaturation including hydrogen bonds. The volatile compounds of the different powders were extracted by solid phase micro-extraction and identified by mass spectrometry. Volatile compounds were related to lipid oxidation and Maillard reactions occurring during the preparation of the powders. High drying temperatures led to more volatile compounds resulting from Maillard reactions. In the protein powder preparation process, a fractionation step led to a “pulp fraction” and a “juice fraction” of earthworms. The “pulp fraction” contained less odorant volatile compounds resulting from Maillard reactions than the “juice fraction” did.展开更多
The influences of arbuscular mycorrhizal fungi (AMF,Acaulospora spp.and Glomus spp.) and rice straw and earthworms (RE,Eisenia foetida) on nematode communities and arsenic (As) uptake by maize (Zea mays L.) in Asconta...The influences of arbuscular mycorrhizal fungi (AMF,Acaulospora spp.and Glomus spp.) and rice straw and earthworms (RE,Eisenia foetida) on nematode communities and arsenic (As) uptake by maize (Zea mays L.) in Ascontaminated soils were examined in a field experiment conducted in Wujiang,Jiangsu Province,China.The experiment was designed as a 2 × 2 factorial with the factors of AMF (inoculated or uninoculated) and RE (added or not added).The results demonstrated that AMF inoculation led to significantly higher root colonization of AMF and root dry weight.Plants inoculated with both AMF and RE had the highest As concentrations in root.The number of total nematodes increased with AMF inoculation when RE was absent,and decreased with RE addition when AMF was inoculated.The improved abundance of nematodes with the AMF treatment implied that the tested AMF acted as food sources for fungivores.The abundances of omnivores-predators and plant parasites were reduced by earthworm activity.Twentyseven genera of nematodes were identified,with Filenchus dominant in all treatments.Trophic diversity,Shannon-Weaver diversity,Simpson dominance index,and species richness indicated higher species diversity,more proportionate species composition,evenly distributed species,and more food sources in the AMF,RE,and their interaction treatments.Maturity index showed a moderately disturbed environment due to As pollution.Besides enhancing plant uptake of contaminants,AMF and RE amendments could also improve soil health by restoring the structure of soil communities,as reflected by more stable nematode community structure.展开更多
[ Objective] To explore the effects of synergy between earthworms （ Eisenia foetida） and effective microorganisms （EM） on vermicom. posting of pig manure and to provide a new idea for rational and effective utiliz...[ Objective] To explore the effects of synergy between earthworms （ Eisenia foetida） and effective microorganisms （EM） on vermicom. posting of pig manure and to provide a new idea for rational and effective utilization and treatment of animal manure. [Method] Four treatments were used to compost pig manure, namely, EM-inoculated manure, earthworms-inoculated manure, EM and earthworms-inoculated manure and control （CK） manure. The experiment lasted for 60 d. On Day 0, 15, 30, 45 and 60, the pig manure was collected, and the content of total organic carbon （TOC）, total Kjeldahl nitrogen （TKN）, ammonium nitrogen, nitrate nitrogen and water soluble carbon （WSC） was determined, respectively. [Resuit] Compared with the control, the EM and earthworms-inoculated manure had a decrease of 42.8% in the TOC content, an increase of 13.6% in the TKN content, a decrease of 49.5% in the carbon nitrogen ratio, the conversion rate of ammonium nitrogen of 98.1%, a 96 times increase in nitrate nitrogen, the ratio of nitrate nitrogen to ammonium nitrogen of 61, and a decrease of 58.9% in the WSC content. [ Conclusion] The synergy between earthworms and EM can accelerate maturation of pig manure and improve mineralization and stability of products.展开更多
文摘Protein powders from Eisenia foetida were prepared using different drying processes and fractionation. Differential scanning calorimetry was used to show that heat denaturation occurred during the drying process above 42°C. Protein solubility was also studied. The addition of dissociating reagents allowed concluding that solubility was decreased during oven drying due to thermo denaturation including hydrogen bonds. The volatile compounds of the different powders were extracted by solid phase micro-extraction and identified by mass spectrometry. Volatile compounds were related to lipid oxidation and Maillard reactions occurring during the preparation of the powders. High drying temperatures led to more volatile compounds resulting from Maillard reactions. In the protein powder preparation process, a fractionation step led to a “pulp fraction” and a “juice fraction” of earthworms. The “pulp fraction” contained less odorant volatile compounds resulting from Maillard reactions than the “juice fraction” did.
基金Project supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX2-YW-408)the Innovative Research International Partnership Program of the Chinese Academy of Sciences (No. CXTD-Z2005-4)the Program of Social Development of Jiangsu Province (No. BS2006025)
文摘The influences of arbuscular mycorrhizal fungi (AMF,Acaulospora spp.and Glomus spp.) and rice straw and earthworms (RE,Eisenia foetida) on nematode communities and arsenic (As) uptake by maize (Zea mays L.) in Ascontaminated soils were examined in a field experiment conducted in Wujiang,Jiangsu Province,China.The experiment was designed as a 2 × 2 factorial with the factors of AMF (inoculated or uninoculated) and RE (added or not added).The results demonstrated that AMF inoculation led to significantly higher root colonization of AMF and root dry weight.Plants inoculated with both AMF and RE had the highest As concentrations in root.The number of total nematodes increased with AMF inoculation when RE was absent,and decreased with RE addition when AMF was inoculated.The improved abundance of nematodes with the AMF treatment implied that the tested AMF acted as food sources for fungivores.The abundances of omnivores-predators and plant parasites were reduced by earthworm activity.Twentyseven genera of nematodes were identified,with Filenchus dominant in all treatments.Trophic diversity,Shannon-Weaver diversity,Simpson dominance index,and species richness indicated higher species diversity,more proportionate species composition,evenly distributed species,and more food sources in the AMF,RE,and their interaction treatments.Maturity index showed a moderately disturbed environment due to As pollution.Besides enhancing plant uptake of contaminants,AMF and RE amendments could also improve soil health by restoring the structure of soil communities,as reflected by more stable nematode community structure.
基金funded by the Scientific Research Foundation of Changsha University (CDJJ-07010107)
文摘[ Objective] To explore the effects of synergy between earthworms （ Eisenia foetida） and effective microorganisms （EM） on vermicom. posting of pig manure and to provide a new idea for rational and effective utilization and treatment of animal manure. [Method] Four treatments were used to compost pig manure, namely, EM-inoculated manure, earthworms-inoculated manure, EM and earthworms-inoculated manure and control （CK） manure. The experiment lasted for 60 d. On Day 0, 15, 30, 45 and 60, the pig manure was collected, and the content of total organic carbon （TOC）, total Kjeldahl nitrogen （TKN）, ammonium nitrogen, nitrate nitrogen and water soluble carbon （WSC） was determined, respectively. [Resuit] Compared with the control, the EM and earthworms-inoculated manure had a decrease of 42.8% in the TOC content, an increase of 13.6% in the TKN content, a decrease of 49.5% in the carbon nitrogen ratio, the conversion rate of ammonium nitrogen of 98.1%, a 96 times increase in nitrate nitrogen, the ratio of nitrate nitrogen to ammonium nitrogen of 61, and a decrease of 58.9% in the WSC content. [ Conclusion] The synergy between earthworms and EM can accelerate maturation of pig manure and improve mineralization and stability of products.
