Background:The objective of this experiment was to evaluate the effect of a combination of microencapsulated essential oils and organic acids(MOA)on growth performance,immuno-antioxidant status,intestinal barrier func...Background:The objective of this experiment was to evaluate the effect of a combination of microencapsulated essential oils and organic acids(MOA)on growth performance,immuno-antioxidant status,intestinal barrier function and microbial structure of the hindgut in piglets.A total of 120 piglets(Duroc×[Landrace×Yorkshire];weighted 7.66±1.79 kg,weaned at d 28)were randomly selected and allocated to 3 treatments with 4 replicates per group and 10 piglets per replicate according to the initial body weight and gender.The dietary treatments were as follows:1)basal diet(Ctrl);2)Ctrl+chlortetracycline(75 mg/kg)(AGP);3)Ctrl+MOA(1500 mg/kg).The experiment period was lasted for 21 d.Results:Compared to the Ctrl group,dietary supplemented MOA alleviated(P<0.05)the diarrhea rate from d 12 to 21,enhanced(P<0.05)the concentration of serum interlukin-10 and glutathione peroxidase in piglets on d 11 after weaning and serum superoxide dismutase in 21-day piglets.The MOA group also improved(P<0.05)the apparent digestibility of dry matter(DM),organic matter(OM)and gross energy(GE),up-regulated(P<0.05)the mRNA expression level of occludin,claudin-1 and mucin-2 in ileum and increased(P<0.05)the contents of propionic and butyric acids in the cecum of piglets.The MOA group modulated the cecal and colonic microbial community structure and increased(P<0.05)the abundance of Faecalibacterium and Muribaculaceae in cecum and Streptococcus and Weissella in colon.Additionally,AGP group decreased(P<0.05)apparent digestibility of DM,OM and GE as well as down-regulated(P<0.05)relative gene expression level of claudin-1 in duodenum and jejunum,ZO-1 and mucin-1 in jejunum of piglets.Conclusion:In summary,dietary supplemented MOA alleviated diarrhea and improved nutrient apparent digestibility in piglets via enhancing immuno-antioxidant properties,increasing digestive enzyme activity,upregulating the expression of intestinal barrier-related genes,and modifying the microbial community structure of the cecum and colon.Therefore,dietary supplementation with MOA as an alternative to antibiotics was feasible to improve intestinal health of piglets in practical production.展开更多
Chelant-enhanced phytoextraction is one of the most promising technologies to remove heavy metals from soil. The key of the technology is to choose suitable additives in combination with a suitable plant. In the prese...Chelant-enhanced phytoextraction is one of the most promising technologies to remove heavy metals from soil. The key of the technology is to choose suitable additives in combination with a suitable plant. In the present study, laboratory batch experiment of metal solubilization, cress seeds germination were undertaken to investigate the metal-mobilizing capability and the phytotoxicity of organic additives, including ethylene diamine triacetic acid (EDTA), citric acid, acetic acid, oxalic acid, glutamine and monosodium glutamate waste liquid (MGWL) from food industry. Experiments in pots were carried out to study the effects of the additives on Zn and Cd phytoextraction. Furthermore, a leaching experiment with lysimeter was performed to evaluate the environmental risks of additive-induced leaching to underground water. The results showed that EDTA had a strong mobilizing ability for Zn and Cd, followed by mixed reagent (MR) and MGWL. MGWL and acetic acid at 5 mmol equivalent per liter resulted in seed germination index less than 2%. Experiments in pots verified the phytotoxicity of acetic acid and MGWL. Addition of the mixed reagent at 6--10 mmol/kg significantly increased Zn phytoextraction by Thlaspi caerulescens. The same for EDTA and the mixed reagent at 10 mmol/kg by Sedum dfredii. But only mixed reagents could significantly increase Cd phytoextraction by the studied hyperaccumulators. This suggested that the strong chelant was not always the good agent to enhance phytoextraction. S. alfredii combined with 2--10 mmol/kg soil MR was preferred for phytoremediation of Cd/Zn contaminated soils in southern China, this could result in high phytoextraction of Cd/Zn and reduce the leaching risk to underground water than EDTA assisted phytoextration.展开更多
Metal organic frameworks(MOFs)constructed from natural/biological units(amino acids)are prospective candidates as catalysts in CO2chemistry owing to their natural origin and high abundance of Lewis acid/base sites and...Metal organic frameworks(MOFs)constructed from natural/biological units(amino acids)are prospective candidates as catalysts in CO2chemistry owing to their natural origin and high abundance of Lewis acid/base sites and functional groups.Herein,we report the catalytic efficiency of an amino‐acid‐based Cu‐containing MOF,denoted as CuTrp(Trp=L‐tryptophan).The CuTrp catalyst was synthesized by direct mixing at room temperature using methanol as a solvent-a synthetic route with notable energy efficiency.The catalyst was characterized using various physicochemical techniques,including XRD,FT‐IR,TGA,XPS,ICP‐OES,FE‐SEM,and BET analysis.The catalytic activity of CuTrp was assessed in the synthesis of cyclic carbonates from epoxides and CO2.The CuTrp operated in synergy with the co‐catalyst tetrabutylammonium bromide under solvent‐free conditions.Several reaction parameters were studied to identify the optimal reaction conditions and a reaction mechanism was proposed based on experimental evidence and previous density functional theory studies.The CuTrp also exhibited satisfactory stability in water and could be reused more than three times without any significant loss of activity.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved.展开更多
基金supported by the National Natural Science Foundation of China(31772612)Beijing Municipal Natural Science Foundation(6202019).
文摘Background:The objective of this experiment was to evaluate the effect of a combination of microencapsulated essential oils and organic acids(MOA)on growth performance,immuno-antioxidant status,intestinal barrier function and microbial structure of the hindgut in piglets.A total of 120 piglets(Duroc×[Landrace×Yorkshire];weighted 7.66±1.79 kg,weaned at d 28)were randomly selected and allocated to 3 treatments with 4 replicates per group and 10 piglets per replicate according to the initial body weight and gender.The dietary treatments were as follows:1)basal diet(Ctrl);2)Ctrl+chlortetracycline(75 mg/kg)(AGP);3)Ctrl+MOA(1500 mg/kg).The experiment period was lasted for 21 d.Results:Compared to the Ctrl group,dietary supplemented MOA alleviated(P<0.05)the diarrhea rate from d 12 to 21,enhanced(P<0.05)the concentration of serum interlukin-10 and glutathione peroxidase in piglets on d 11 after weaning and serum superoxide dismutase in 21-day piglets.The MOA group also improved(P<0.05)the apparent digestibility of dry matter(DM),organic matter(OM)and gross energy(GE),up-regulated(P<0.05)the mRNA expression level of occludin,claudin-1 and mucin-2 in ileum and increased(P<0.05)the contents of propionic and butyric acids in the cecum of piglets.The MOA group modulated the cecal and colonic microbial community structure and increased(P<0.05)the abundance of Faecalibacterium and Muribaculaceae in cecum and Streptococcus and Weissella in colon.Additionally,AGP group decreased(P<0.05)apparent digestibility of DM,OM and GE as well as down-regulated(P<0.05)relative gene expression level of claudin-1 in duodenum and jejunum,ZO-1 and mucin-1 in jejunum of piglets.Conclusion:In summary,dietary supplemented MOA alleviated diarrhea and improved nutrient apparent digestibility in piglets via enhancing immuno-antioxidant properties,increasing digestive enzyme activity,upregulating the expression of intestinal barrier-related genes,and modifying the microbial community structure of the cecum and colon.Therefore,dietary supplementation with MOA as an alternative to antibiotics was feasible to improve intestinal health of piglets in practical production.
基金The Hi-Tech Research and Development Program (863) of China (No. 2001-AA-640501-3)French-Chinese Programme deRecherche Avancee (No. PRA E-03-02) the National Natural Science Foundation of China (No. 40571141)
文摘Chelant-enhanced phytoextraction is one of the most promising technologies to remove heavy metals from soil. The key of the technology is to choose suitable additives in combination with a suitable plant. In the present study, laboratory batch experiment of metal solubilization, cress seeds germination were undertaken to investigate the metal-mobilizing capability and the phytotoxicity of organic additives, including ethylene diamine triacetic acid (EDTA), citric acid, acetic acid, oxalic acid, glutamine and monosodium glutamate waste liquid (MGWL) from food industry. Experiments in pots were carried out to study the effects of the additives on Zn and Cd phytoextraction. Furthermore, a leaching experiment with lysimeter was performed to evaluate the environmental risks of additive-induced leaching to underground water. The results showed that EDTA had a strong mobilizing ability for Zn and Cd, followed by mixed reagent (MR) and MGWL. MGWL and acetic acid at 5 mmol equivalent per liter resulted in seed germination index less than 2%. Experiments in pots verified the phytotoxicity of acetic acid and MGWL. Addition of the mixed reagent at 6--10 mmol/kg significantly increased Zn phytoextraction by Thlaspi caerulescens. The same for EDTA and the mixed reagent at 10 mmol/kg by Sedum dfredii. But only mixed reagents could significantly increase Cd phytoextraction by the studied hyperaccumulators. This suggested that the strong chelant was not always the good agent to enhance phytoextraction. S. alfredii combined with 2--10 mmol/kg soil MR was preferred for phytoremediation of Cd/Zn contaminated soils in southern China, this could result in high phytoextraction of Cd/Zn and reduce the leaching risk to underground water than EDTA assisted phytoextration.
文摘Metal organic frameworks(MOFs)constructed from natural/biological units(amino acids)are prospective candidates as catalysts in CO2chemistry owing to their natural origin and high abundance of Lewis acid/base sites and functional groups.Herein,we report the catalytic efficiency of an amino‐acid‐based Cu‐containing MOF,denoted as CuTrp(Trp=L‐tryptophan).The CuTrp catalyst was synthesized by direct mixing at room temperature using methanol as a solvent-a synthetic route with notable energy efficiency.The catalyst was characterized using various physicochemical techniques,including XRD,FT‐IR,TGA,XPS,ICP‐OES,FE‐SEM,and BET analysis.The catalytic activity of CuTrp was assessed in the synthesis of cyclic carbonates from epoxides and CO2.The CuTrp operated in synergy with the co‐catalyst tetrabutylammonium bromide under solvent‐free conditions.Several reaction parameters were studied to identify the optimal reaction conditions and a reaction mechanism was proposed based on experimental evidence and previous density functional theory studies.The CuTrp also exhibited satisfactory stability in water and could be reused more than three times without any significant loss of activity.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved.