Straw return is an effective management practice. It not only utilizes agricultural waste but also introduces dissolved organic matter(DOM) into the soil. Selenium(Se) is an essential trace element in the human diet a...Straw return is an effective management practice. It not only utilizes agricultural waste but also introduces dissolved organic matter(DOM) into the soil. Selenium(Se) is an essential trace element in the human diet and contributes to the popularity of Se-enriched agricultural products in the Chinese market. Moreover, there are still some Se-enriched agricultural products that have yet to be utilized. This study investigated whether Se addition in soil caused component changes in the DOM extracted from rape straw. DOM extracted from rape straw grown in soil with four Se levels(0, 0.1, 0.5 and 1.0 mg Se kg-1 soil) was characterized by UV-Visible spectroscopy, fluorescence spectroscopy and FTIR spectroscopy. The UVvisible spectra revealed that 0.1 mg Se kg-1 soil reduced the molecular weight of DOM and caused the presence of more irreplaceable aromatic structures in the substituent groups of the DOM, while 0.5 and 1.0 mg Se kg-1 soil only reduced the DOM molecular weight. Fluorescence spectroscopy indicated that Se improved the humification degree but reduced the aromaticity of DOM. FTIR spectra proved that Se altered the contents of carboxylic acids, amino acids, alcohols and aromatic heterocycles in DOM, which were maximized in the 0.5 and 1.0 mg Se kg-1 treatment groups. We concluded that Se application could change the composition of DOM extracted from rape straw, potentially impacting the nutrient bioavailability in soil. This study provides basic data on Se-enriched rape straw utilization for eco-agriculture.展开更多
Butyric acid is a volatile saturated monocarboxylic acid,which is widely used in the chemical,food,pharmaceutical,energy,and animal feed industries.This study focuses on producing butyric acid from pre-treated rape st...Butyric acid is a volatile saturated monocarboxylic acid,which is widely used in the chemical,food,pharmaceutical,energy,and animal feed industries.This study focuses on producing butyric acid from pre-treated rape straw using simultaneous enzymatic hydrolysis semi-solid fermentation(SEHSF).Clostridium beijerinckii BRM001 screened from pit mud of Chinese nongxiangxing baijiu was used.The genome of C.beijerinckii BRM001 was sequenced and annotated.Using rape straw as the sole carbon source,fermentation optimization was carried out based on the genomic analysis of BRM001.The optimized butyric acid yield was as high as 13.86±0.77 g/L,which was 2.1 times higher than that of the initial screening.Furthermore,under optimal conditions,non-sterile SEHSF was carried out,and the yield of butyric acid was 13.42±0.83 g/L in a 2.5-L fermentor.This study provides a new approach for butyric acid production which eliminates the need for detoxification of straw hydrolysate and makes full use of the value of fermentation waste residue without secondary pollution,making the whole process greener and more economical,which has a certain industrial potential.展开更多
Screening of cost-effective soil amendments is important to develop ＂in situ＂ remediation techniques for cadmium （Cd） contaminated soils. In this study, different soil amendments, including red mud, a by-product o...Screening of cost-effective soil amendments is important to develop ＂in situ＂ remediation techniques for cadmium （Cd） contaminated soils. In this study, different soil amendments, including red mud, a by-product of the alumina industry, and acid-treated, nano-treated by nanoparticle milling, nano and acid-treated red muds, zeolite, corn straw, and rape straw, were evaluated to immobilize Cd in two added levels （2 and 5 mg Cd·kg^-1 soil） in a calcareous soil by single and sequential extractions and by cucumber （Cucumis sativus L.） pot experiments. Results indicated that cruciferous rape straw significantly decreased the concentrations of water soluble, extractable Cd in soils, and Cd in cucumber plants, and it was more effective than gramineous corn straw. Also, red mud generally decreased the extractability and bioavailability of Cd added to calcareous soils more effectively than zeolite. Furthermore, the efficiency of red mud could be increased by the treatment of nano-particle milling due to the increase in specific surface area of red mud. It is potential to use rape straw and red mud as soil amendments to develop a cost-effective and efficient ＂in situ＂ rernediation technology for Cd mildly contaminated calcareous soils.展开更多
基金This work was supported by the National Natural Science Foundation of China(41571321 and 31201501)the Fundamental Research Funds for the Central Universities of China(2662018JC057)the Opening Project of Key Laboratory of Testing and Evaluation for Agro-product Safety and Quality,Ministry of Agriculture and Rural Affairs of China(NK201702).
文摘Straw return is an effective management practice. It not only utilizes agricultural waste but also introduces dissolved organic matter(DOM) into the soil. Selenium(Se) is an essential trace element in the human diet and contributes to the popularity of Se-enriched agricultural products in the Chinese market. Moreover, there are still some Se-enriched agricultural products that have yet to be utilized. This study investigated whether Se addition in soil caused component changes in the DOM extracted from rape straw. DOM extracted from rape straw grown in soil with four Se levels(0, 0.1, 0.5 and 1.0 mg Se kg-1 soil) was characterized by UV-Visible spectroscopy, fluorescence spectroscopy and FTIR spectroscopy. The UVvisible spectra revealed that 0.1 mg Se kg-1 soil reduced the molecular weight of DOM and caused the presence of more irreplaceable aromatic structures in the substituent groups of the DOM, while 0.5 and 1.0 mg Se kg-1 soil only reduced the DOM molecular weight. Fluorescence spectroscopy indicated that Se improved the humification degree but reduced the aromaticity of DOM. FTIR spectra proved that Se altered the contents of carboxylic acids, amino acids, alcohols and aromatic heterocycles in DOM, which were maximized in the 0.5 and 1.0 mg Se kg-1 treatment groups. We concluded that Se application could change the composition of DOM extracted from rape straw, potentially impacting the nutrient bioavailability in soil. This study provides basic data on Se-enriched rape straw utilization for eco-agriculture.
基金supported by grants from the National Natural Science Foundation of China(Grant No.31801522)the Cooperation Project of Wuliangye Group Co.,Ltd.and Sichuan University of Science&Engineering,China(CXY2019ZR011)Sichuan University of Science&Engineering(Item No.2020RC36).
文摘Butyric acid is a volatile saturated monocarboxylic acid,which is widely used in the chemical,food,pharmaceutical,energy,and animal feed industries.This study focuses on producing butyric acid from pre-treated rape straw using simultaneous enzymatic hydrolysis semi-solid fermentation(SEHSF).Clostridium beijerinckii BRM001 screened from pit mud of Chinese nongxiangxing baijiu was used.The genome of C.beijerinckii BRM001 was sequenced and annotated.Using rape straw as the sole carbon source,fermentation optimization was carried out based on the genomic analysis of BRM001.The optimized butyric acid yield was as high as 13.86±0.77 g/L,which was 2.1 times higher than that of the initial screening.Furthermore,under optimal conditions,non-sterile SEHSF was carried out,and the yield of butyric acid was 13.42±0.83 g/L in a 2.5-L fermentor.This study provides a new approach for butyric acid production which eliminates the need for detoxification of straw hydrolysate and makes full use of the value of fermentation waste residue without secondary pollution,making the whole process greener and more economical,which has a certain industrial potential.
基金This work was financially supported by Special Fund for Agro-scientific Research in the Public Interest （No. 200903015） 973 Program （No. 2014CB238906） and 863 Program （No. 2013AA06A21r2）. We are also very grateful to the National Natural Science Foundation of China （Grant No. 41201312, 41250110528） for financial support.
文摘Screening of cost-effective soil amendments is important to develop ＂in situ＂ remediation techniques for cadmium （Cd） contaminated soils. In this study, different soil amendments, including red mud, a by-product of the alumina industry, and acid-treated, nano-treated by nanoparticle milling, nano and acid-treated red muds, zeolite, corn straw, and rape straw, were evaluated to immobilize Cd in two added levels （2 and 5 mg Cd·kg^-1 soil） in a calcareous soil by single and sequential extractions and by cucumber （Cucumis sativus L.） pot experiments. Results indicated that cruciferous rape straw significantly decreased the concentrations of water soluble, extractable Cd in soils, and Cd in cucumber plants, and it was more effective than gramineous corn straw. Also, red mud generally decreased the extractability and bioavailability of Cd added to calcareous soils more effectively than zeolite. Furthermore, the efficiency of red mud could be increased by the treatment of nano-particle milling due to the increase in specific surface area of red mud. It is potential to use rape straw and red mud as soil amendments to develop a cost-effective and efficient ＂in situ＂ rernediation technology for Cd mildly contaminated calcareous soils.
