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1.
J Org Chem ; 89(1): 527-533, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38095905

RESUMO

Transition metal catalysts with a million turnovers and excellent selectivity are rarely reported but are crucial for the industrial manufacture of optical pure pharmaceuticals, natural products, and fine chemicals. In this paper, we report an unprecedented aninoic Ir-f-phamidol catalyst for asymmetric hydrogenation of γ-amino ketones followed by stereoselective cyclization for construction of valuable chiral 2-aryl-pyrrolidine pharmacophores. The Ir-f-phamidol catalyst showed up to 1,000,000 TON and >99% ee, as well as excellent tolerance of substrates and protecting groups, providing various chiral amino alcohol intermediates. Upon optimization of the conditions, the stereoselective cyclization reaction was highly smooth and efficient (quantitative conversions, 92 to >99% ee). Finally, this solution was applied in the preparation of high-value chiral entities containing such chiral 2-aryl-pyrrolidine pharmacophores.

2.
Phys Chem Chem Phys ; 26(25): 17769-17776, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38873788

RESUMO

Perovskites exhibit considerable potential as catalysts for various applications, yet their performance modulation in the carbon dioxide reduction reaction (CO2RR) remains underexplored. In this study, we report a strategy to enhance the electrocatalytic carbon dioxide (CO2) reduction activity via Ce-doped La2CuO4 (LCCO) and Sr-doped La2CuO4 (LSCO) perovskite oxides. Specifically, compared to pure phase La2CuO4 (LCO), the Faraday efficiency (FE) for CH4 of LCCO at -1.4 V vs. RHE (reversible hydrogen electrode) is improved from 38.9% to 59.4%, and the FECO2RR of LSCO increased from 68.8% to 85.4%. In situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy spectra results indicate that the doping of A-site ions promotes the formation of *CHO and *HCOO, which are key intermediates in the production of CH4, compared to the pristine La2CuO4. X-ray photoelectron spectroscopy (XPS), electron paramagnetic resonance (EPR), and double-layer capacitance (Cdl) outcomes reveal that heteroatom-doped perovskites exhibit more oxygen vacancies and higher electrochemical active surface areas, leading to a significant improvement in the CO2RR performance of the catalysts. This study systematically investigates the effect of A-site ion doping on the catalytic activity center Cu and proposes a strategy to improve the catalytic performance of perovskite oxides.

3.
Angew Chem Int Ed Engl ; : e202410517, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896017

RESUMO

Electrochemical nitrogen oxide ions reduction reaction (NOx-RR) shows great opportunity for ammonia production under ambient conditions. Yet, performing NOx-RR in strong acidic conditions remains challenging due to the corrosion effect on the catalyst and competing hydrogen evolution reactions. Here, we demonstrate a stable La1.5Sr0.5Ni0.5Fe0.5O4 perovskite oxide for the NOx-RR at pH 0, achieving a Faradaic efficiency for ammonia of approaching 100% at a current density of 2 A cm-2 in a H-type cell. At industrially relevant current density, the NOx-RR system shows stable cell voltage and Faradaic efficiency for >350 h in membrane electrode assembly (MEA) at pH 0. By integrating the catalyst in a stacked MEA with a series connection, we have successfully obtained a record-breaking 2.578 g h-1 NH3 production rate at 20 A. This catalyst's unique acid-operability streamlines downstream ammonia utilization for direct ammonium salt production and upstream integration with NOx sources. Techno-economic and lifecycle assessments reveal substantial economic advantages for this ammonia production strategy, even when coupled with a plasma-based NOx production system, presenting a sustainable complement to the conventional Haber-Bosch process.

4.
Ann Surg ; 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38073601

RESUMO

OBJECTIVE: To compare the surgical outcomes of robotic-assisted proctosigmoidectomy (RAP) and laparoscopic-assisted Soave pull-through (LAP) for children with Hirschsprung's disease (HD). SUMMARY BACKGROUND DATA: LAP and RAP have been developed for minimally invasive pull-through of HD, but the clinical benefits of robotic-assisted versus laparoscopic-assisted approaches have yet to be proven in a multicenter prospective study. METHODS: This study was a prospective multicenter clinical trial conducted on children with rectosigmoid/descending HD from July 2015 to June 2022, with registration in the Chinese Clinical Trial Registry (ChiCTR2000035220). The primary outcome was the medium-term functional outcomes in children aged ≥4 years based on bowel functional scores, which were assessed and compared between LAP and RAP. RESULTS: A total of 328 consecutive patients (RAP=165, LAP=163) were approached who were considered eligible for elective minimally invasive endorectal pull-through, and 219 patients aged ≥4 years of age completed follow-up (RAP=109, LAP=110). The transanal dissection length and anal traction time were significantly shorter in RAP than those in LAP (0.30 cm vs. 3.70 cm, P <0.001; 45 min vs. 62 min, P <0.001). The RAP group had significantly lower urinary retention rate (0% vs. 5.52%, P=0.006), while other short-term results between two groups were not significantly different. The medium-term overall BFS scores were comparable between two groups; however, among the subgroup of children aged ≤ 3 months at surgery, the RAP group had better anal canal resting pressure at one year postoperatively and amounted to better annual POFC scores at 4-7 years old postoperatively (all P <0.05). CONCLUSIONS: RAP and LAP should have similar medium-term bowel functional outcomes in HD children, but RAP may be associated with a slight functional benefit in infants operated on below age 3 months, requiring further investigation in larger case cohorts.

5.
Opt Express ; 31(17): 27735-27748, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710842

RESUMO

We theoretically study the phase estimation based on a Mach-Zehnder interferometer (MZI) with a two-mode squeezed coherent state. By maximizing the quantum Fisher information, we find that the quantum Cramér-Rao bounds (QCRB) can reach sub-Heisenberg limit under the phase-matched condition. The optimal phase sensitivity can reach the sub-shot noise limit (SNL) and approach the QCRB by employing the intensity difference detection. Meanwhile, compared with the MZI fed with a coherent plus a single-mode squeezed vacuum state, this scheme can have better performance by adjusting the squeezing parameter and the mean photon number. With the same parameter, our scheme shows more sensitive phase measurement than the SU(1,1) interferometer with a coherent plus a vacuum state. We also show that the phase sensitivity of our proposal can still reach the SNL when the loss of the photon is 36%. This scheme can provide potential applications in optical sensors.

6.
Faraday Discuss ; 243(0): 473-491, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37016973

RESUMO

With the increase in the greenhouse effect and reduction of fossil fuel resources, it is urgent to find a feasible solution to directly convert power to chemicals using renewable energy and achieving zero carbon emissions targets. It is necessary to convert renewable energy (i.e., solar, wind, water, etc.) into electrical power replacing fossil-fuel-fired power. Therefore, the power-to-chemicals approach is gaining more and more attention. In the past two decades, non-thermal plasma, electro-catalysis, photo-catalysis, and their hybrid approaches have shown great potential for the power-to-chemicals solution. This paper introduces the application of plasma technology in energy conversion, focusing on three main routes for plasma-enabled ammonia synthesis, and analyses the state-of-the-art. Research results of ammonia synthesis based on plasma technology are discussed. The application of advanced in situ diagnostics evidences the importance of specific intermediate species and reaction pathways. Electrons, vibrationally-excited species, free radicals, and surface-adsorbed species play important roles in plasma-catalytic ammonia synthesis. Combined with experiments and simulations, the mechanisms of plasma-catalytic ammonia synthesis are examined. Vibrationally-excited species can effectively reduce the catalytic surface energy barrier. The techno-economics of the plasma-enabled ammonia synthesis technology is discussed in view of its competitive advantages. It is emphasized that the power-to-chemicals approach can be adapted for most chemical manufacturers, and these methods would play crucial roles in reducing carbon emissions and environmental pollution. Finally, suggestions are provided for the sustainable development of the power-to-chemicals industry in the future.

7.
J Appl Microbiol ; 134(9)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37596068

RESUMO

AIMS: To determine the fermentation quality, aerobic stability, and chemical composition of Italian ryegrass silage prepared with Lactobacillus plantarum (LP), caproic acid (CA), and their combination during ensiling and feed-out phase. METHODS AND RESULTS: Six treatments: control (CON), LP, 0.15% caproic acid (LCA), 0.2% caproic acid (HCA), LCA + LP, and HCA + LP were employed for 30 days ensiling and an 8-days aerobic stability test. LP had similar pH value and lactic acid content with LCA + LP, while the contents of NH3-N and total VFAs in LCA + LP were significantly lower than those in LP and CON, and the fermentation quality of LCA + LP performed best among all silages. As air-exposure extended, contents of water-soluble carbohydrates (WSC), lactic, and acetic acids decreased, while pH, and NH3-N content increased significantly. The population of lactic acid bacteria gradually decreased in contrast to increased counts of aerobic bacteria and yeasts. Compared with LCA, 0.2% CA delayed the aerobic deterioration as judged by a slower increase in pH and high residual of WSC and lactic acid, and negligible ethanol content and anaerobe spores counts remained in HCA at the end of air exposure. Compared with CON (73 h), LP showed less aerobic stability (38 h), whereas HCA and HCA + LP prolonged aerobic stability for 210 and 152 h, better than LCA (109 h) and LCA + LP (146 h). CONCLUSIONS: Lactobacillus plantarum apparently improved the fermentation quality, and combined with CA exhibited greater efficiency in inhibiting undesirable microorganism during ensiling. CA at 0.2% optimally extended the aerobic stability.


Assuntos
Lactobacillus plantarum , Lolium , Caproatos , Fermentação , Silagem , Ácido Láctico , Água , Itália
8.
Surg Endosc ; 37(5): 3540-3547, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36602550

RESUMO

BACKGROUND: Robotic-assisted Kasai portoenterostomy (RAKPE) has been utilized to treat biliary atresia (BA). However, RAKPE is not widely performed and its efficacy remains unknown. We summarized the experience of RAKPE for BA and determined its efficacy. MATERIALS AND METHODS: We retrospectively analyzed 25 consecutive infants with non-syndromic type III BA who received RAKPE in our center from January 2020 to July 2021. RAKPE is a three-arm setup and four-trocar operation. Bipolar coagulation was used to dissect the small blood vessels at the hepatic portal. The fibrous cone was shallowly transected with bending electric scissors, followed by gelatin sponge compression to staunch the hemorrhage. Finally, a wide anastomosis was accurately constructed. Demographics and outcomes were recorded. RESULTS: The mean operative time was 211.64 ± 18.93 min. No conversion to laparotomy or intraoperative complications occurred. The mean estimated blood loss was 7.64 ± 2.43 mL. Enteral feeding was resumed after 3.44 ± 1.23 days. All patients achieved bile excretion postoperatively, and dark green bile-stained stools were passed 1.50 days (range 1.00-3.00 days) after surgery. The average postoperative length of hospital stay was 10.32 ± 2.59 days. The jaundice clearance (JC) rate was 76.00% within 6 months after surgery and the incidence of cholangitis was 48.00% within 1 year following surgery. The survival with native liver (SNL) rate was 80.00% at 1 year and 66.67% at 2 years. CONCLUSION: RAKPE can be regarded as a treatment option for patients with BA due to the good outcomes reported. However, long-term studies comparing open or laparoscopic approaches are needed.


Assuntos
Atresia Biliar , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Lactente , Humanos , Atresia Biliar/cirurgia , Portoenterostomia Hepática , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Laparoscopia/efeitos adversos , Resultado do Tratamento
9.
Surg Endosc ; 37(1): 31-47, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35913517

RESUMO

BACKGROUND: Most commonly, cyst excision and Roux-en-Y hepaticojejunostomy reconstruction are the optimal treatment for choledochal cysts (CC). Robotic surgery (RS) is being conducted with increasing frequency to treat CC. It is unclear whether RS can overcome the limitations of laparoscopic surgery (LS) and improve the prognosis of patients. In terms of efficacy, evidence concerning which minimally invasive surgery is preferred is, however, sparse. Our objective is to further compare the efficacy of RS and LS in children with CC and draw a useful clinical conclusion. METHODS: Studies meeting inclusion criteria were identified from a series of databases, consisting of PubMed, Embase, Scopus, Web of Science, the Cochrane Library and their reference list of articles up to May 2022. Eligible articles comprised at least five objects that were younger than 18 years of age and the language was limited to English. Two authors independently evaluated selected studies and extracted data for analysis. RESULTS: Forty studies were selected for analysis, with thirty-six reporting data on LS and eight containing data on RS. The pooled conversion rate and pooled postoperative complication rate of RS were lower than those of LS, but none of them was statistically significant. Moreover, comparisons of the following detailed postoperative complication rates were not statistically significant, such as intestinal obstruction or ileus, anastomotic bleeding, anastomotic or bile leakage, and anastomotic stenosis. However, the intraoperative blood loss and the postoperative hospital stay in RS group were significantly lower than those in LS group. CONCLUSIONS: RS is a safe and feasible option for children with CC. Further studies with more cases, long-term efficacy and health economics analysis are needed to confirm whether RS is more advantageous.


Assuntos
Cisto do Colédoco , Obstrução Intestinal , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Criança , Humanos , Anastomose em-Y de Roux , Cisto do Colédoco/cirurgia , Obstrução Intestinal/cirurgia , Laparoscopia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Resultado do Tratamento
10.
Surg Endosc ; 37(7): 5077-5085, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36917343

RESUMO

OBJECTIVE: The objective of the study was to assess the validity of the NASA-TLX score in rating the workload of pediatric robotic operations. METHODS: The workload of 230 pediatric gastrointestinal and thoracic robotic operations was rated using the NASA-TLX score. The difference between the high workload group and the low workload group in each subscale of the NASA-TLX score was analyzed. The correlation of each subscale with the total workload score in the high workload group and low workload group was also analyzed. A logistic regression analysis was subsequently conducted to assess the effects of different factors (sex, age, weight, procedure duration, procedure specialties, combined malformation and blood loss) on the workload. RESULTS: The average NASA-TLX score was 56.5 ± 5.1 for the total group, 56.9 ± 5.0 for the gastrointestinal group and 54.6 ± 4.8 for the thoracic group, p = 0.007. The score of the high workload group was 62.7 ± 3.2, while it was 50.6 ± 2.7 for the low workload group (p < 0.001). The score on each subscale was also significantly different between the high and low workload groups. In the high workload group, a stronger correlation was observed between the total score and TD and Fr and a lower correlation with MD and Pe. In the low workload group, all six subscales showed a moderate correlation with the total score. A multivariate logistic regression analysis revealed that the procedure duration was an independent influencing factor for a higher workload score. CONCLUSIONS: NASA-TLX is a valid tool to rate the surgeon's workload in pediatric robotic surgery. A longer operative time contributes to a higher workload.


Assuntos
Procedimentos Cirúrgicos Robóticos , Especialidades Cirúrgicas , Estados Unidos , Humanos , Criança , Carga de Trabalho , United States National Aeronautics and Space Administration , Inquéritos e Questionários , Análise e Desempenho de Tarefas
11.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688771

RESUMO

The present study aimed to evaluate the effects of delayed harvest and storage length on fermentation products, bacterial community, and metabolic shifts of elephant grass silage. The late-harvested elephant grass (LG) was naturally fermented (NLG) for 1, 3, 7, 15, 30, and 60 days, respectively. After 60-day ensiling, NLG displayed homolactic fermentation with low pH value, butyric acid, and ammonia nitrogen concentrations, and high lactic acid concentration, and ratio of lactic acid to acetic acid. Pseudomonas, Sphingomonas, and Pantoea dominated the bacterial community in LG, but Lactobacillus, Lactococcus, and Pediococcus were the advantageous genera in a 3-day and 60-day NLG. The correlation heatmap revealed that Acetobacter was positively related to acetic acid, ethanol, ammonia nitrogen, and butyric acid concentrations. There were distinct differences in the KEGG (Kyoto Encyclopedia of Genes and Genomes) metabolic profiles of fresh and ensiled LG. Ensiling suppressed the metabolism of amino acid, vitamins, and energy, while promoted the metabolism of carbohydrate. The LG can be well-fermented without additives, but its low crude protein content should not be ignored when applied in agricultural practice. The ensiling process remarkably affected the fermentation quality, bacterial community, and metabolic profiles of NLG.


Assuntos
Amônia , Silagem , Fermentação , Ácido Butírico/metabolismo , Silagem/microbiologia , Amônia/metabolismo , Bactérias , Ácido Acético/metabolismo , Ácido Láctico/metabolismo , Metaboloma
12.
J Sci Food Agric ; 103(1): 221-232, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35857393

RESUMO

BACKGROUND: The use of alfalfa is a promising response to the increasing demand for squalene. Ensiling could enhance the squalene content of fresh alfalfa and silage. To investigate and exploit the anaerobic fermentation of forage as a new squalene source, alfalfa was ensiled without (CON) or with molasses (ML) and sunflower seed oil (SSL) for 10, 40, and 70 days. RESULTS: Naturally ensiled alfalfa was of poor quality but had up to 1.93 times higher squalene content (P < 0.001) than fresh alfalfa. The squalene-producing bacteria were found to be cocci lactic acid bacteria (LAB). Adding ML and SSL decreased squalene content (P = 0.002 and P < 0.001) by 6.89% and 11.6%, respectively. Multiple linear regression models and correlation analysis indicated that squalene synthase was the key enzyme for squalene synthesis. The addition of ML and SSL altered the structure of LAB communities, mainly decreasing the relative abundance of cocci LAB, which was responsible for squalene synthesis, and changing the fermentation products (lactic acid, propionic acid, and ammonia-N) influencing the squalene-related enzymes, thereby decreasing squalene production. Compared with squalene production from the reference bacteria (Pediococcus acidilactici Ch-2, Rhodopseudomonas palustris, Bacillus subtilis, engineered Escherichia coli), alfalfa silage had the potential to be a new squalene source. CONCLUSION: Natural ensiled alfalfa was a promising source for squalene, and ensiling was a potential pathway to obtain novel high-yield squalene bacteria. © 2022 Society of Chemical Industry.


Assuntos
Medicago sativa , Esqualeno , Medicago sativa/química , Fermentação , Anaerobiose , Silagem/análise , Bactérias/genética
13.
J Sci Food Agric ; 103(3): 1385-1393, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36151894

RESUMO

BACKGROUND: The influence of epiphytic microbiota and chemical composition on fermentation quality and microbial community of Italian ryegrass silage was evaluated. Italian ryegrass harvested at the filling stage (FS) and the dough stage (DS) was sterilized by gamma-ray irradiation and inoculated as follows: (I) FS epiphytic microbiota + irradiated FS (FF); (II) FS epiphytic microbiota + irradiated DS (FD); (III) DS epiphytic microbiota + irradiated DS (DD); (IV) DS epiphytic microbiota + irradiated FS (DF). RESULTS: After 60 days of ensiling, silage made from irradiated FS had a lower pH and ammonia nitrogen (NH3 -N) content and a higher lactic acid (LA) content than that made from irradiated DS. Similarly, silage inoculated with the epiphytic microbiota of DS had a lower pH and NH3 -N content and a higher LA content than that inoculated with the epiphytic microbiota of FS. However, LA-type fermentation (lactic acid:acetic acid > 2:1) was presented at DF and DD. The principal coordinates analysis showed that the distance between FF and DF and FD and DD was closer than other treatments, suggesting that the microbial community of silages made from irradiated FS (or DS) was more similar. CONCLUSION: The epiphytic microbiota played a more important role in the fermentation type, whereas the chemical composition had a great influence on the contents of fermentation end-products. However, chemical composition had a stronger effect on the microbial community of silage than the epiphytic microbiota. © 2022 Society of Chemical Industry.


Assuntos
Lolium , Microbiota , Silagem/análise , Fermentação , Ácido Láctico , Itália
14.
J Sci Food Agric ; 103(7): 3272-3286, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36810766

RESUMO

BACKGROUND: The present study aimed to investigate the relationship between the phyllosphere microbiota of Italian ryegrass (Lolium multiflorum Lam.) harvested at heading (H) [> 50% earing rate or 216 g kg-1 fresh weight (FW)] and blooming (B) (> 50% bloom or 254 g kg-1 FW) stages and in-silo fermentation products, and the composition, abundance, diversity and activity of bacterial community. In total, 72 (4 treatments × 6 ensiling durations × 3 replicates) laboratory scale (400 g) silages of Italian ryegrass were prepared: (i) irradiated heading stage silages (IRH) (n = 36) were inoculated with phyllosphere microbiota inoculum (2 mL) eluted from fresh Italian ryegrass at either heading (IH) (n = 18) or blooming (IB) (n = 18) stages; (ii) irradiated blooming stage silages (IRB) (n = 36) were inoculated with either IH (n = 18) or IB (n = 18). Triplicate silos of each treatment were analyzed after 1, 3, 7, 15, 30 and 60 days of ensiling. RESULTS: In fresh forage, Enterobacter, Exiguobacterium and Pantoea were the three major genera at heading stage, and Rhizobium, Weissella and Lactococcus were the most abundant genera at blooming stage. Higher metabolic activity was found in IB. After 3 days of ensiling, the large amounts of lactic acid in IRH-IB and IRB-IB can be attributed to the higher abundances of Pediococcus and Lactobacillus, 1-phosphofructokinase, fructokinase, l-lactate dehydrogenase and glycolysis I, II and III. CONCLUSION: The composition, abundance, diversity and functionality of the phyllosphere microbiota of Italian ryegrass at different growth stages could remarkably affect silage fermentation characteristics. © 2023 Society of Chemical Industry.


Assuntos
Lolium , Microbiota , Lolium/microbiologia , Fermentação , Lactobacillus/metabolismo , Itália , Silagem/análise
15.
J Sci Food Agric ; 103(12): 5981-5991, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37115188

RESUMO

BACKGROUND: Mycotoxins contamination in food and feed has emerged as an issue of serious concern because they pose serious health risks to both humans and livestock. The study aimed to evaluate the effects of two rumen-derived Enterococcus spp. on fermentation and hygienic quality of artificially contaminated corn silages. The toxigenic fungal-infested (FI) and non-fungal infested (NFI) corn was harvested at 1/2 milk line stage and ensiled without additives (CON) or with Enterococcus faecalis (E) or Enterococcus faecium (M). RESULTS: The pH of FI silages was higher than that of NFI silages, the pH in NFI-M was lower than in NFI-CON. Inoculating E. faecium markedly increased lactic acid concentration compared to CON and E silages. Both E. faecium and E. faecalis decreased the deoxynivalenol (DON) and zearalenone (ZEN) concentrations compared with the CON for FI silages, while E. faecium was more effective in eliminating aflatoxin B1 (AFB1 ). The FI silage had higher bacterial and fungal Shannon indexes than NFI silages. The relative abundance (RA) of Aspergillus and Fusarium marked a decline from day 5 to day 90. Inoculating E. faecium and E. faecalis reduced the RA of Penicillium compared to CON. In vitro mycotoxins removal assay indicated that E. faecium was more effective in AFB1 detoxification while having lower detoxifying ZEN capacity than E. faecalis. CONCLUSION: Inoculating rumen-derived Enterococcus spp. isolates alleviated the negative effects of fungal infestation on the fermentation and hygienic quality of corn silages by changing the microbial communities and detoxifying mycotoxins. © 2023 Society of Chemical Industry.


Assuntos
Micotoxinas , Zearalenona , Animais , Humanos , Zea mays/química , Micotoxinas/metabolismo , Silagem/análise , Antifúngicos/metabolismo , Enterococcus , Rúmen/metabolismo , Zearalenona/metabolismo , Fermentação
16.
J Anim Physiol Anim Nutr (Berl) ; 107(5): 1149-1157, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36541284

RESUMO

Two experiments were carried out to determine the optimal proportion of mixed silage made with wheat straw and tall fescue, and further to evaluate the effects of molasses on fermentation quality. In Experiment 1, wheat straw and tall fescue were mixed at proportions of 10:0 (Control), 8:2 (WT20), 6:4 (WT40) and 4:6 (WT60) on fresh weight (FW) basis. Inclusion of tall fescue significantly (p < 0.05) increased lactic acid, water-soluble carbohydrate contents and ratio of lactic to acetic acid, and significantly (p < 0.05) decreased pH and contents of dry matter, NH3 -N and volatile fatty acids. WT60 had the highest (p < 0.05) lactic acid content, and the lowest (p < 0.05) pH and butyric acid content. In Experiment 2, the mixture of wheat straw and tall fescue (4/6) were treated with 0%, 3%, 4% and 5% molasses on FW basis (defined as control, WTM3, WTM4 and WTM5 respectively). Molasses addition significantly (p < 0.05) increased lactic acid and water-soluble carbohydrate contents, and significantly (p < 0.05) decreased pH and ammonia-nitrogen content as compared with control. Acetic acid content slightly (p > 0.05) decreased during ensiling, while trace amounts of propionic and butyric acids were observed. WTM5 had the lowest pH and the highest (p < 0.05) lactic acid, water-soluble carbohydrate contents and ratio of lactic to acetic acid at end of ensiling. In conclusion, the fermentation quality was maximally improved when the addition rate of molasses was 5% in 40% wheat straw ensiled with 60% tall fescue.


Assuntos
Melaço , Triticum , Animais , Fermentação , Tibet , Silagem/análise , Carboidratos , Ácido Láctico , Ácido Acético
17.
J Anim Physiol Anim Nutr (Berl) ; 107(2): 340-349, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35500045

RESUMO

The effects of wet brewers grains (WBG) on fermentation quality, chemical composition and in vitro ruminal digestibility of mixed silages prepared with corn stalk, dried apple pomace and sweet potato peel were evaluated. A mixture of corn stalk, sweet potato peel and dried apple pomace (50/30/20) was ensiled with 0, 10%, 20% and 30% WBG on a fresh weight (FW) basis for 1, 3, 5, 7, 14 and 30 days respectively. The results showed that the application of WBG increased (p < 0.05) lactic acid, acetic acid and total volatile fatty acids contents, and decreased (p < 0.05) pH, dry matter, water-soluble carbohydrates content and ammonia-nitrogen/total nitrogen during ensiling. The pH in all silages was below 4.03 during ensiling. Treating with WBG increased (p < 0.05) crude protein content, and decreased (p < 0.05) neutral detergent fibre, acid detergent fibre, cellulose and hemicellulose content after 30 days of ensiling. After 72 h of incubation, cumulative gas production, potential gas production and in vitro crude protein digestibility increased (p < 0.05) with the increasing proportions of WBG. However, in vitro digestibility of dry matter and neutral detergent fibre, and metabolisable energy were similar in all silages. The 20% and 30% WBG-treated silages showed better fermentation quality and greater or higher in vitro digestibility, which were indicated by greater or higher (p < 0.05) lactic acid content, in vitro crude protein digestibility, and lower (p < 0.05) pH, ammonia-nitrogen/total nitrogen ratio as compared with the control. Therefore, ensiling agro-food by-products with at least 20% WBG were recommended for improving fermentation quality.


Assuntos
Ipomoea batatas , Malus , Animais , Silagem/análise , Zea mays/química , Amônia/metabolismo , Fermentação , Detergentes/metabolismo , Carboidratos , Ácido Láctico/metabolismo , Nitrogênio/metabolismo , Proteínas/metabolismo
18.
Angew Chem Int Ed Engl ; 62(25): e202303868, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37086028

RESUMO

The atom- and step-efficient synthesis of chiral fused tricyclic lactams from readily available ketoesters using cheap ammonium salts as the nitrogen source is reported. This ruthenium-catalyzed system operates through an efficient tandem dynamic kinetic asymmetric reductive amination (ARA)/lactamization and produces chiral fused tricyclic lactams in high yields with excellent diastereo- and enantioselectivity (up to >99 % ee, >20 : 1 dr and 98 % yield). The robust method was also applied to the concise synthesis of key intermediates in the synthesis of rivastigmine analogues and chiral N-heterocyclic carbene catalysts.


Assuntos
Compostos de Amônio , Lactamas , Aminação , Sais , Catálise
19.
Chembiochem ; 23(14): e202200217, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35575966

RESUMO

Impaired mitophagy hinders the clearance of damaged mitochondria, inducing pathological states. Knowledge of this phenomenon is key to diagnosing certain diseases and understanding their pathogenesis. Mitophagy involves an acidization process that could serve as an ideal detection target. In this work, we designed and synthesized a mitochondrial-targeting fluorescence probe, Z2, for evaluating pH variation. This probe exhibited remarkable "turn-on" fluorescence under acidic conditions. In biological applications, Z2 showed a strong, specific pH detection capacity in Parkin-overexpressing HeLa cells during the mitophagy process. The "turn-on" fluorescence property of Z2 was also used to detect pH variations in Caenorhabditis elegans. This probe, as a novel pH assessment tool, may facilitate further research of mitophagy-associated pathological patterns.


Assuntos
Corantes Fluorescentes , Mitofagia , Animais , Caenorhabditis elegans , Corantes Fluorescentes/química , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Mitocôndrias , Pirimidinas , Ubiquitina-Proteína Ligases
20.
J Org Chem ; 87(24): 16941-16946, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36473047

RESUMO

Converting cheap and abundant internal alkenes to value-added linear aldehydes is of great importance but not an addressed issue. In this paper, an integration of a Milstein-type Ru-PNN catalyst and our Rh-Tribi/Tetrabi catalyst was first demonstrated in highly improved isomerization linear selective hydroformylation of 2-, 3-, and 4-alkenes, yielding excellent linear selectivities and activities (linear selectivity improvements of 2.2-58%, up to 94.2-98.6%, and turnover numbers improvements of 61-335 TON, up to 385-851) compared to the Ru-PNN/Rh-Bisbi system.

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