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1.
Huan Jing Ke Xue ; 45(6): 3584-3594, 2024 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-38897778

RESUMO

In order to investigate the effects of ammonium sulfate, an industrial by-product, on soil nutrients and microbial community when applied in different proportions instead of using urea as nitrogen fertilizer, a pot corn experiment was conducted. A completely randomized block experimental design was used, with a total of five treatments:CK (no fertilization), U10S0 (100 % urea), U8S2 (80 % urea + 20 % ammonium sulfate), U6S4(60 % urea + 40 % ammonium sulfate), and U0S10 (100 % ammonium sulfate). The basic physical and chemical properties of soil and the dry weight of maize plants were determined by conventional methods, and microbial sequencing was performed using the Illumina NovaSeq platform. The experiment results showed that:① In each growth stage of maize, the pH of soil treated with fertilization (7.85-8.15) was decreased compared with that of CK (8.1-8.21), and the pH showed a decreasing trend with the increase in ammonium sulfate content. ② The soil available nitrogen content increased gradually with the increase in the ammonium sulfate ratio at each growth stage of maize. Compared with that in the CK and U10S0 treatments, the ratio in the U0S10 treatment increased 30.56 % to 63.68 % and 13.22 % to 38.43 %, respectively. The variation trend of organic carbon content was opposite to that of available nitrogen (U8S2 > U6S4 > U0S10), and the addition of ammonium sulfate was still higher than that of U10S0 at other growth stages except for the seedling stage. ③ The protease activity of all fertilization treatments was higher than that of the control, and the protease activity was gradually enhanced with the continuous growth of corn and the increase in the ammonium sulfate ratio. The protease activity of the U0S10 treatment was higher than that of the U10S0 treatment at each growth stage of corn, which increased by 10.54 %-100 %. Soil sucrase activity ranged from 0.04 to 0.24 mg·(g·24 h)-1, and those in the U0S10 treatments were significantly higher than those in the U10S0 and CK treatments at all growth stages, increasing by 20.32 % to 99.16 % and 24.31 % to 79.33 %, respectively. ④ The species abundance of bacteria and fungi in maize rhizosphere under all fertilization treatments were lower than those under the CK treatment, followed by those under the U10S0 treatment. The species diversity trend of the bacterial community in the three treatments with ammonium sulfate replacing urea were U8S2 > U0S10 > U6S4, and that of fungi were U6S4 > U8S2 > U0S10. ⑤ The maize dry weight of the U10S0 treatment and U0S10 treatment was the highest, which was 39.47 % and 36.16 % higher than that of the CK treatment, respectively, but the difference was not significant. The Pearson model showed that the species abundance and diversity of soil rhizosphere fungi and bacteria were affected by relevant environmental variables, among which pH value and soil available nitrogen content were the most important factors affecting microbial diversity. In conclusion, when corn planting in calcareous brown soil, replacing urea with a certain proportion of ammonium sulfate can improve soil nutrients more than urea alone, which affects the growth and rhizosphere microbial community of corn to a certain extent and has a greater yield.


Assuntos
Sulfato de Amônio , Fertilizantes , Nitrogênio , Rizosfera , Microbiologia do Solo , Solo , Ureia , Zea mays , Zea mays/crescimento & desenvolvimento , Solo/química , Ureia/metabolismo , Microbiota/efeitos dos fármacos
2.
Molecules ; 29(11)2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38893489

RESUMO

Recovering valuable active substances from the by-products of agricultural processing is a crucial concern for scientific researchers. This paper focuses on the enrichment of soybean trypsin inhibitor (STI) from soybean whey wastewater using either ammonium sulfate salting or ethanol precipitation, and discusses their physicochemical properties. The results show that at a 60% ethanol content, the yield of STI was 3.983 mg/mL, whereas the yield was 3.833 mg/mL at 60% ammonium sulfate saturation. The inhibitory activity of STI obtained by ammonium sulfate salting out (A-STI) was higher than that obtained by ethanol precipitation (E-STI). A-STI exhibited better solubility than E-STI at specific temperatures and pH levels, as confirmed by turbidity and surface hydrophobicity measurements. Thermal characterization revealed that both A-STI and E-STI showed thermal transition temperatures above 90 °C. Scanning electron microscopy demonstrated that A-STI had a smooth surface with fewer pores, while E-STI had a rough surface with more pores. In conclusion, there was no significant difference in the yield of A-STI and E-STI (p < 0.05); however, the physicochemical properties of A-STI were superior to those of E-STI, making it more suitable for further processing and utilization. This study provides a theoretical reference for the enrichment of STI from soybean whey wastewater.


Assuntos
Glycine max , Inibidores da Tripsina , Águas Residuárias , Soro do Leite , Glycine max/química , Águas Residuárias/química , Soro do Leite/química , Inibidores da Tripsina/química , Inibidores da Tripsina/isolamento & purificação , Sulfato de Amônio/química , Precipitação Química , Concentração de Íons de Hidrogênio , Solubilidade , Interações Hidrofóbicas e Hidrofílicas , Temperatura
3.
Artigo em Inglês | MEDLINE | ID: mdl-38878711

RESUMO

OBJECTIVE: Optimize the extraction process of earthworm fibrinolytic enzyme. METHODS: Chinese common earthworms underwent a series of purification processes, including grinding, salting out, hydrophobic medium chromatography, ammonium sulfate precipitation, and ion exchange chromatography, to obtain purified earthworm fibrinolytic enzyme. RESULTS: Utilizing Pheretima aspergillum as the starting material, we discovered that the specific activity of lumbrokinase extracted via ammonium sulfate precipitation was 58 U/mg, noticeably surpassing that achieved through heat precipitation and ethanol precipitation methods. After undergoing two rounds of chromatographic separations employing hydrophobic affinity chromatography and anion exchange chromatography, the specific activity of the lumbrokinase protein soared to 9267 U/mg, significantly exceeding the 3,178 U/mg specific activity attained through industrial extraction methods. DISCUSSION: The development of a novel crude extraction method for lumbrokinase protein can significantly boost its activity and purity. The discovery of a high-efficiency purification method and the identification of protein components within highly active lumbrokinase pave the way for further investigations into these proteins.


Assuntos
Oligoquetos , Oligoquetos/química , Oligoquetos/enzimologia , Animais , Cromatografia por Troca Iônica/métodos , Sulfato de Amônio/química , Cromatografia de Afinidade/métodos , Precipitação Química , Interações Hidrofóbicas e Hidrofílicas , Fracionamento Químico/métodos , Endopeptidases
4.
Int J Biol Macromol ; 273(Pt 1): 133034, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38862052

RESUMO

Exploring new biomass sources for nanocellulose (NC) extraction is crucial in elevating the economic value of readily available renewable resources. This study compares NC extracted from acai (Euterpe oleracea) bagasse using different methods: mixed acid hydrolysis, 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) mediation, and ammonium persulfate (APS) oxidations. A comprehensive analysis investigates the impact of each treatment on the physical-chemical properties of the nanoparticles, including chemical structure, crystallinity, morphology, and thermal and suspension stability. NCs obtained through mixed acid hydrolysis exhibit the highest crystallinity (62 %) and low sulfate groups on their surfaces. Consequently, they demonstrate excellent thermal stability but poor colloidal stability in water. Oxidized NCs undergo chemical modification, converting alcoholic groups into carboxyl, resulting in NCs with zeta potentials ranging between -25.30 ± 0.81 and - 27.49 ± 1.07 mV. APS oxidation produces nanoparticles with superior thermal stability compared to TEMPO oxidation. Atomic Force Microscopy (AFM) images reveal that all nanocelluloses share characteristics of nanofibers (CNFs). This comprehensive characterization highlights the potential of acai bagasse for yielding high-added-value bioproducts suitable for versatile applications.


Assuntos
Celulose , Oxirredução , Celulose/química , Hidrólise , Óxidos N-Cíclicos/química , Nanopartículas/química , Sulfato de Amônio/química , Microscopia de Força Atômica
5.
Food Res Int ; 190: 114595, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945610

RESUMO

R-phycoerythrin (R-PE) is the most abundant, naturally occurring phycobiliproteins found in red algae. The spectroscopic and structural properties of phycobiliproteins exhibit unique absorption characteristics with two significant absorption maxima at 498 and 565 nm, indicating two different chromophores of R-PE, phycourobilin and phycoerythrobilin respectively. This study aimed to clarify how the stability of R-PE purified from F. lumbricalis was affected by different purification strategies. Crude extracts were compared to R-PE purified by i) microfiltration, ii) ultrafiltration, and iii) multi-step ammonium sulphate precipitation followed by dialysis. The stability of the different R-PE preparations was evaluated with respect to pH (2, 4, 6, 7, 8, 10 and 12) and temperature (20, 40, 60, 80 and 100 °C). The absorbance spectra indicated higher stability of phycourobilin as compared to phycoerythrobilin for heat and pH stability in the samples. All preparations of R-PE showed heat stability till 40 °C from the findings of color, concentration of R-PE and fluorescence emission. The crude extract showed stability from pH 6 to 8, whereas R-PE purified by ultrafiltration and multi-step ammonium sulphate precipitation were both stable from pH 4 to 8 and R-PE purified by microfiltration exhibited stability from pH 4 to 10 from the results of color, SDS-PAGE, and concentration of R-PE. At pH 2, the color changed to violet whereas a yellow color was observed at pH 12 in the samples along with the precipitation of the protein.


Assuntos
Ficoeritrina , Rodófitas , Ficoeritrina/química , Ficoeritrina/isolamento & purificação , Concentração de Íons de Hidrogênio , Rodófitas/química , Ultrafiltração/métodos , Estabilidade Proteica , Precipitação Química , Sulfato de Amônio/química , Temperatura Alta , Temperatura
6.
Int J Food Microbiol ; 419: 110749, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38788343

RESUMO

This study investigated the synergistic effects of ammonium persulfate (PS) and ultrasound (US) on the inactivation of Escherichia coli O157:H7 in buffered peptone water (BPW) and orange juice products. A comprehensive assessment of PS concentrations ranging from 1 to 300 mM, considering not only the statistical significance but also the reliability and stability of the experimental outcomes, showed that 150 mM was the optimal PS concentration for the inactivation of E. coli O157:H7. Additionally, US output intensities varying from 30 % to 60 % of the maximum US intensity were evaluated, and 50 % US amplitude was found to be the optimal US condition. A 50 % amplitude setting on the sonicator corresponds to half of its maximum displacement, approximately 60 µm, based on a maximum amplitude of 120 µm. The inactivation level of E. coli O157:H7 was significantly enhanced by the combined treatment of PS and US, compared to each treatment of PS and US alone. In the BPW, a 10-min treatment with the combination of PS and US resulted in a significant synergistic inactivation, achieving up to a log reduction of 3.86 log CFU/mL. Similarly, in orange juice products, a 5-min treatment with the combination of PS and US yielded a significant synergistic inactivation, with a reduction reaching 5.90 log CFU/mL. Although the treatment caused a significant color change in the sample, the visual differences between the treated and non-treated groups were not pronounced. Furthermore, the combined treatment in orange juice demonstrated significantly enhanced antimicrobial efficacy relative to BPW. Despite identical 5-min treatment periods, the application in orange juice resulted in a substantially higher log reduction of E. coli O157:H7, achieving 7.16 log CFU/mL at a reduced PS concentration of 30 mM, whereas the same treatment in BPW yielded only a 2.89 log CFU/mL reduction at a PS concentration of 150 mM, thereby highlighting its significantly superior antimicrobial performance in orange juice. The mechanism underlying microbial inactivation, induced by the combined treatment of PS and US, was identified as significant cell membrane damage. This damage is mediated by sulfate radicals, generated through the sono-activation of persulfate. In addition, the low pH of orange juice, measured at 3.7, is likely to have further deteriorated the E. coli O157:H7 cells compared to BPW (pH 7.2), by disrupting their cell membranes, proton gradients, and energy metabolism. These findings underscore the effectiveness of PS and US integration as a promising approach for non-thermal pasteurization in the food industry. Further research is needed to optimize treatment parameters and fully explore the practical application of this technique in large-scale food processing operations. Sensory evaluation and nutritional assessment are also necessary to address the limitations of PS.


Assuntos
Sulfato de Amônio , Citrus sinensis , Contagem de Colônia Microbiana , Escherichia coli O157 , Sucos de Frutas e Vegetais , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/crescimento & desenvolvimento , Sucos de Frutas e Vegetais/microbiologia , Citrus sinensis/química , Sulfato de Amônio/farmacologia , Sulfato de Amônio/química , Peptonas/farmacologia , Peptonas/química , Microbiologia de Alimentos , Viabilidade Microbiana/efeitos dos fármacos , Água/química , Água/farmacologia
7.
Molecules ; 29(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38611831

RESUMO

In addition to traditional use in fermented dairy products, S. thermophilus also exhibits anti-inflammatory properties both in live and heat-inactivated form. Recent studies have highlighted that some hydrolysates from surface proteins of S. thermophilus could be responsible partially for overall anti-inflammatory activity of this bacterium. It was hypothesized that anti-inflammatory activity could also be attributed to peptides resulting from the digestion of intracellular proteins of S. thermophilus. Therefore, total intracellular proteins (TIP) from two phenotypically different strains, LMD-9 and CNRZ-21N, were recovered by sonication followed by ammonium sulphate precipitation. The molecular masses of the TIP of both strains were very close to each other as observed by SDS-PAGE. The TIP were fractionated by size exclusion fast protein liquid chromatography to obtain a 3-10 kDa intracellular protein (IP) fraction, which was then hydrolysed with pancreatic enzyme preparation, Corolase PP. The hydrolysed IP fraction from each strain exhibited anti-inflammatory activity by modulating pro-inflammatory mediators, particularly IL-1ß in LPS-stimulated THP-1 macrophages. However, a decrease in IL-8 secretion was only observed with hydrolysed IP fraction from CNRZ-21N, indicating that strain could be an important parameter in obtaining active hydrolysates. Results showed that peptides from the 3-10 kDa IP fraction of S. thermophilus could therefore be considered as postbiotics with potential beneficial effects on human health. Thus, it can be used as a promising bioactive ingredient for the development of functional foods to prevent low-grade inflammation.


Assuntos
Proteínas de Membrana , Streptococcus thermophilus , Humanos , Sulfato de Amônio , Interleucina-1beta , Macrófagos
8.
Biomed Res Int ; 2024: 4119960, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559901

RESUMO

Background: Lactobacillus acidophilus is lactic acid bacteria that produce bacteriocins. Bacteriocins are antimicrobial peptides or proteins that exhibit activity against closely related bacteria. The aim of this study was to determine the effect of L. acidophilus ATCC 4356 bacteriocin against Staphylococcus aureus. Material and Methods. We used four different phenotypic methods for antimicrobial activities against two standard strains: methicillin-resistant S. aureus (MRSA) ATCC 33591 and methicillin-susceptible S. aureus (MSSA) ATCC 25923. The methods were (1) agar well diffusion, (2) overlay soft agar, (3) paper disk, and (4) modification of punch hole. The ammonium sulfate method was used to concentrate crude bacteriocin, and ultrafiltration and dialysis tubes were used to remove ammonium sulfate from the bacteriocins. Each method was repeated in triplicate. Result: L. acidophilus ATCC 4356 showed antimicrobial activity against both MRSA and MSSA standard strains only by the overlay soft agar method and not by the agar well diffusion, punch hole modification, and paper disk methods. No antimicrobial effects were observed in crude bacteriocins concentrated. Conclusion: The growth inhibition of S. aureus in overlay soft agar method may be due to the production of bacteriocin-like substances. The overlay soft agar method is a qualitative test, so there is a need for further study to optimize the conditions for the production of bacteriocin-like substances in the culture supernatant and precise comparison between the inhibitory activity and pheromone secretion of different strains.


Assuntos
Anti-Infecciosos , Bacteriocinas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Bacteriocinas/metabolismo , Lactobacillus acidophilus , Ágar/metabolismo , Sulfato de Amônio/metabolismo , Sulfato de Amônio/farmacologia , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-38632039

RESUMO

The mutant strain Halomonas bluephagenesis (TDH4A1B5P) was found to produce PHA under low-salt, non-sterile conditions, but the yield was low. To improve the yield, different nitrogen sources were tested. It was discovered that urea was the most effective nitrogen source for promoting growth during the stable stage, while ammonium sulfate was used during the logarithmic stage. The growth time of H. bluephagenesis (TDH4A1B5P) and its PHA content were significantly prolonged by the presence of sulfate ions. After 64 hr in a 5-L bioreactor supplemented with sulfate ions, the dry cell weight (DCW) of H. bluephagenesis weighed 132 g/L and had a PHA content of 82%. To promote the growth and PHA accumulation of H. bluephagenesis (TDH4A1B5P), a feeding regimen supplemented with nitrogen sources and sulfate ions with ammonium sodium sulfate was established in this study. The DCW was 124 g/L, and the PHA content accounted for 82.3% (w/w) of the DCW, resulting in a PHA yield of 101 g/L in a 30-L bioreactor using the optimized culture strategy. In conclusion, stimulating H. bluephagenesis (TDH4A1B5P) to produce PHA is a feasible and suitable strategy for all H. bluephagenesis.


Assuntos
Reatores Biológicos , Meios de Cultura , Halomonas , Nitrogênio , Poli-Hidroxialcanoatos , Sulfatos , Halomonas/metabolismo , Halomonas/crescimento & desenvolvimento , Halomonas/genética , Sulfatos/metabolismo , Poli-Hidroxialcanoatos/metabolismo , Meios de Cultura/química , Nitrogênio/metabolismo , Sulfato de Amônio/metabolismo , Ureia/metabolismo , Fermentação
10.
Microb Cell Fact ; 23(1): 120, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38664812

RESUMO

BACKGROUND: The conversion of plant biomass into biochemicals is a promising way to alleviate energy shortage, which depends on efficient microbial saccharification and cellular metabolism. Trichoderma spp. have plentiful CAZymes systems that can utilize all-components of lignocellulose. Acetylation of polysaccharides causes nanostructure densification and hydrophobicity enhancement, which is an obstacle for glycoside hydrolases to hydrolyze glycosidic bonds. The improvement of deacetylation ability can effectively release the potential for polysaccharide degradation. RESULTS: Ammonium sulfate addition facilitated the deacetylation of xylan by inducing the up-regulation of multiple carbohydrate esterases (CE3/CE4/CE15/CE16) of Trichoderma harzianum. Mainly, the pathway of ammonium-sulfate's cellular assimilates inducing up-regulation of the deacetylase gene (Thce3) was revealed. The intracellular metabolite changes were revealed through metabonomic analysis. Whole genome bisulfite sequencing identified a novel differentially methylated region (DMR) that existed in the ThgsfR2 promoter, and the DMR was closely related to lignocellulolytic response. ThGsfR2 was identified as a negative regulatory factor of Thce3, and methylation in ThgsfR2 promoter released the expression of Thce3. The up-regulation of CEs facilitated the substrate deacetylation. CONCLUSION: Ammonium sulfate increased the polysaccharide deacetylation capacity by inducing the up-regulation of multiple carbohydrate esterases of T. harzianum, which removed the spatial barrier of the glycosidic bond and improved hydrophilicity, and ultimately increased the accessibility of glycosidic bond to glycoside hydrolases.


Assuntos
Esterases , Metionina , Esterases/metabolismo , Esterases/genética , Metionina/metabolismo , Xilanos/metabolismo , Sulfato de Amônio/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Hypocreales/metabolismo , Hypocreales/enzimologia , Hypocreales/genética , Lignina/metabolismo , Acetilação
11.
J Agric Food Chem ; 72(15): 8742-8748, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38564658

RESUMO

Tyrosinase is capable of oxidizing tyrosine residues in proteins, leading to intermolecular protein cross-linking, which could modify the protein network of food and improve the texture of food. To obtain the recombinant tyrosinase with microbial cell factory instead of isolation tyrosinase from the mushroom Agaricus bisporus, a TYR expression cassette was constructed in this study. The expression cassette was electroporated into Trichoderma reesei Rut-C30 and integrated into its genome, resulting in a recombinant strain C30-TYR. After induction with microcrystalline cellulose for 7 days, recombinant tyrosinase could be successfully expressed and secreted by C30-TYR, corresponding to approximately 2.16 g/L tyrosinase in shake-flask cultures. The recombinant TYR was purified by ammonium sulfate precipitation and gel filtration, and the biological activity of purified TYR was 45.6 U/mL. The purified TYR could catalyze the cross-linking of glycinin, and the emulsion stability index of TYR-treated glycinin emulsion was increased by 30.6% compared with the untreated one. The cross-linking of soy glycinin by TYR resulted in altered properties of oil-in-water emulsions compared to emulsions stabilized by native glycinin. Therefore, cross-linking with this recombinant tyrosinase is a feasible approach to improve the properties of protein-stabilized emulsions and gels.


Assuntos
Reagentes de Ligações Cruzadas , Expressão Gênica , Globulinas , Hypocreales , Monofenol Mono-Oxigenase , Proteínas Recombinantes , Proteínas de Soja , Monofenol Mono-Oxigenase/biossíntese , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/isolamento & purificação , Monofenol Mono-Oxigenase/metabolismo , Reagentes de Ligações Cruzadas/isolamento & purificação , Reagentes de Ligações Cruzadas/metabolismo , Hypocreales/classificação , Hypocreales/genética , Hypocreales/crescimento & desenvolvimento , Hypocreales/metabolismo , Globulinas/química , Globulinas/metabolismo , Proteínas de Soja/química , Proteínas de Soja/metabolismo , Eletroporação , Celulose , Sulfato de Amônio , Cromatografia em Gel , Precipitação Fracionada , Emulsões/química , Emulsões/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Estabilidade Proteica , Retículo Endoplasmático/metabolismo , Sinais Direcionadores de Proteínas , Óleos/química , Água/química
12.
Pestic Biochem Physiol ; 199: 105804, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458671

RESUMO

Chemical fertilizer and pesticide are necessary in agriculture, which have been frequently used, sometimes even at the same time or in combination. To understand the interactions of them could be of significance for better use of these agrochemicals. In this study, the influence of chemical fertilizers (urea, potassium sulfate, ammonium sulfate and superphosphate) on the control efficacy and environmental behavior of abamectin was investigated, which could be applied in soil for controlling nematodes. In laboratory assays, ammonium sulfate at 1 and 2 g/L decreased the LC50 values of abamectin to Meloidogyne incognita from 0.17 mg/L to 0.081 and 0.043 mg/L, indicating it could increase the contact toxicity. In greenhouse trial, ammonium sulfate at 1000 mg/kg increased the control efficacy of abamectin by 1.37 times. Meanwhile, the combination of abamectin with ammonium sulfate could also promote the tomato seedling growth as well as the defense-related enzyme activity under M. incognita stress. The persistence and mobility of abamectin in soil were significantly elevated by ammonium sulfate, which could prolong and promote the control efficacy against nematodes. These results could provide reference for reasonable use of abamectin and fertilizers so as to increase the control efficacy and minimize the environmental risks.


Assuntos
Fertilizantes , Ivermectina/análogos & derivados , Tylenchoidea , Animais , Solo , Sulfato de Amônio
13.
Chemosphere ; 352: 141317, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38286306

RESUMO

The efficacy of using plants to phytoremediate heavy metal (HM) contaminated soils can be improved using soil amendments. These amendments may both increase plant biomasses and HMs uptake. We aimed to determine the composite effect of ammonium sulfate ((NH4)2SO4) combined with the application of an aqueous stem-extracted bio-chelator (Bidens tripartita L) on the plant biomasses and cadmium (Cd) phytoextraction by Solanum nigrum L. The constant (NH4)2SO4 application mode plus bio-chelator additives collectively enhanced the shoot Cd extraction ability owing to the increased plant biomass and shoot Cd concentration by S. nigrum. The shoot Cd extraction and the soil Cd decreased concentration confirmed the optimal Cd phytoextraction pattern in K8 and K9 treatments (co-application of (NH4)2SO4 and twofold/threefold bio-chelators). Accordingly, Cd contamination risk in the soil (2 mg kg-1) could be completely eradicated (<0.2 mg kg-1) after three rounds of phytoremediation by S.nigrum based on K8 and K9 treatments through calculating soil Cd depletion. The microorganism counts and enzyme activities in rhizosphere soils at treatments with the combined soil additives apparently advanced. In general, co-application mode of (NH4)2SO4 and aqueous bio-chelator was likely to be a perfect substitute for conventional scavenger agents on account of its environmental friendliness and cost saving for field Cd contamination phytoremediation by S. nigrum.


Assuntos
Poluentes do Solo , Solanum nigrum , Cádmio/análise , Quelantes , Sulfato de Amônio/farmacologia , Poluentes do Solo/análise , Biodegradação Ambiental , Solo , Raízes de Plantas/química
14.
Environ Res ; 247: 118194, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38224934

RESUMO

To attenuate the risk of Cadmium(Cd) contamination and the deterioration of soil quality caused by excessive nitrogen fertilizer application in greenhouse, a composite organic amendment (spend mushroom substrate and its biochar) was prepared to remedy Cd(II) ions contaminated soil (0.6 mg/kg) under different N fertilizer levels. The results showed that in the absence of a composite organic amendment, the soil pH decreased by 0.15 when the N level increased from 0.1 to 0.8 g N⋅kg-1. However, the pH increased by 0.86-0.91, the exchangeable Cd(II) ions content decreased by 26.0%-26.7%, the microbial biomass increased by 34.34%-164.46%, and the number of copies of the AOB gene increased by 13-20 times with the application of composite organic amendment and the increase of N level. Both Pearson correlation analysis and Mantel test demonstrated the reduction in Cd(II) ions availability, the restoration of soil properties and the increase in microbial biomass all contributed to the composite organic amendment, which is of importance for soil remediation under excessive N fertilizer.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/análise , Sulfato de Amônio/análise , Sulfatos , Fertilizantes/análise , Poluentes do Solo/análise , Solo/química
15.
J Appl Lab Med ; 9(2): 350-356, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38180079

RESUMO

BACKGROUND: Examination of urine by immunofixation electrophoresis (UIFE) is one of the tests recommended for screening and monitoring of monoclonal gammopathies, especially multiple myeloma. Unlike the serum free light chain measurement, a positive result on urine immunofixation is diagnostic for monoclonal immunoglobulin light chains. Urine is usually concentrated, generally by membrane filtration, prior to electrophoresis. METHODS: Alternative methods to membrane filtration for urine concentration were examined. Residual urine specimens submitted for urine protein electrophoresis were concentrated by precipitation of the proteins by ammonium sulfate salt precipitation, precipitation with ethanol and acetonitrile, and by desiccation. The concentrated specimens were subjected to immunofixation electrophoresis using antisera to free light chains (FLC). The results were compared with those from conventional immunofixation electrophoresis using specimens concentrated by membrane filtration. RESULTS: Ammonium sulfate, ethanol, and acetonitrile precipitation results were less than satisfactory. Concentration by desiccation provided results comparable, if not better than, those by membrane filtration and conventional UIFE. The cost of desiccation is minimal compared to more than $5.00/specimen cost of concentration by membrane filtration. The differences in the results with conventional UIFE and the method described here are likely due to (a) variability in the reactivity of different antisera to free monoclonal light chains, and (b) obscuration of monoclonal free light chains by co-migration with intact immunoglobulin monoclonal proteins. CONCLUSIONS: Concentrating urine by desiccation for immunofixation electrophoresis is technically simple, inexpensive, and provides results comparable to concentrating by membrane filtration. Using FLC provides a more sensitive assay than using conventional antisera.


Assuntos
Gamopatia Monoclonal de Significância Indeterminada , Humanos , Sulfato de Amônio , Cadeias Leves de Imunoglobulina , Acetonitrilas , Etanol , Soros Imunes
16.
Environ Technol ; 45(11): 2196-2204, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36606665

RESUMO

This study aims to explore the influence mechanism of ammonium nitrate produced by ozone denitrification on the crystallisation of ammonium sulfate, a by-product of ammonia desulfurisation. The laser method was used to study the influence of ammonium nitrate on the solubility and metastable zone width of ammonium sulfate. An experiment on the influence of ammonium nitrate on the particle size of ammonium sulfate was designed, and the influence mechanism was explored through scanning electron microscopy and X-ray diffraction. The findings showed that the addition of ammonium nitrate increased the size and aspect ratio of ammonium sulfate crystals. The addition of ammonium nitrate inhibited the dissolution of ammonium sulfate and widened its metastable zone. The addition of ammonium nitrate covered the active sites of crystal nucleus growth, which inhibited the formation of crystal nuclei to a certain extent, and crystal growth dominated the crystallisation process. Moreover, the addition of ammonium nitrate induced the preferred orientation of the specific crystal plane of ammonium sulfate, and the addition of a small concentration of ammonium nitrate decreased the crystallinity of ammonium sulfate. The research results can provide a reference for crystallisation optimisation and quality improvement of ammonium sulfate in the ammonia desulfurisation process.


Assuntos
Amônia , Compostos de Amônio , Sulfato de Amônio , Cristalização , Nitratos/química , Compostos de Amônio/química
17.
Prep Biochem Biotechnol ; 54(1): 115-125, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37652437

RESUMO

Aqueous two-phase extraction (ATPE) has been extensively utilized for the extraction and separation of tiny-molecule substances as a new system (system with short-chain ethanol and inorganic salts). In this study, an innovative method of extracting anthocyanins from mulberry was developed, employing microwave-assisted extraction with ethanol/ammonium sulfate as a biphasic extractant. Response surface methodology (RSM) was utilized to optimize anthocyanin extraction conditions: 39% ethanol (w/w), 13% ammonium sulfate (w/w), and liquid-to-solid ratio of 45:1, microwave duration 3 min, microwave temperature 32 °C, and microwave power 480 Watt (W). High-performance liquid chromatography (HPLC) analysis demonstrated no significant differences in the structure of mulberry anthocyanins before and after MAATPE treatment, furthermore. The extraction behavior of MAATPE was due to hydrogen bonding, according to Fourier transform infrared spectroscopy (FT-IR). Scanning electron microscopy analysis found that MAATPE damaged the cell structure via a microwave enhancement effect, which was more favorable to anthocyanin dissolution than standard extraction methods. The DPPH free radical scavenging rate of mulberry extracts at 0.5 mg/mL was higher than that of vitamin C (96.4 ± 0.76%), and the ABTS free radical scavenging rate (82.52 ± 2.13%) was close to that of vitamin C, indicating that MAATPE-derived mulberry extracts have good antioxidant activity.


Assuntos
Produtos Biológicos , Morus , Antocianinas/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Micro-Ondas , Frutas/química , Sulfato de Amônio , Água/química , Etanol/análise , Ácido Ascórbico , Radicais Livres/análise , Extratos Vegetais/química
18.
Int J Biol Macromol ; 257(Pt 1): 128599, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38056738

RESUMO

High-performance biomass materials with good thermal insulation, flame retardrancy, and mechanical properties are urgently required for thermal management. Herein, a novel lignocellulose aerogel treated using a recyclable deep eutectic solvent (DES) was physically mixed with tourmaline particles (TPs) to enhance its structural stability, flame retardancy, and mechanical properties. The optimized TPs-modified lignocellulose aerogel (TLA-4) had good comprehensive performances due to the synergistic effect of ammonium sulfate and TPs. Compared with TPs-free lignocellulose aerogel (LA), the total heat release (THR) and heat release rate (HRR) of TLA-4 were reduced by 62.0 % and 66.3 %, respectively, and the limiting oxygen index (LOI) of TLA-4 was drastically enhanced by 74.1 %. TLA-4 also exhibited a low thermal conductivity of 29.67 mW/mK, showing favorable thermal insulation performance. When compressed to 5 %, the mechanical strength of TLA-4 increased by 8.3 times. Meanwhile, the presence of TPs and abundant pores in the aerogel contributed to the release of negative oxygen ions (NOIs), aiding air purification. A life cycle assessment (LCA) indicated that this composite had a minimal environmental impact (EI) in 17 categories compared to other similar aerogels. The proposed strategy for preparing an environment-friendly lignocellulose aerogel offers significant potential for applications in home decoration and building materials.


Assuntos
Filtros de Ar , Lignina , Animais , Sulfato de Amônio , Oxigênio , Estágios do Ciclo de Vida
19.
Pestic Biochem Physiol ; 197: 105681, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38072538

RESUMO

Rhizoctonia solani is a widespread and devastating plant pathogenic fungus that infects many important crops. This pathogen causes tobacco target spot, a disease that is widespread in many tobacco-growing countries and is destructive to tobacco. To identify antagonistic microorganisms with biocontrol potential against this disease, we isolated Streptomyces strains from forest inter-root soil and screened a promising biocontrol strain, ZZ-21. Based on in vitro antagonism assays, ZZ-21 showed a significant inhibitory effect on R. solani and various other phytopathogens. ZZ-21 was identified as Streptomyces olivoreticuli by its phenotypic, genetic, physiological and biochemical properties. Complete genome sequencing revealed that ZZ-21 harbored numerous antimicrobial biosynthesis gene clusters. ZZ-21 significantly reduced the lesion length in detached inoculated leaf assays and reduced the disease index under greenhouse and field conditions. Based on an in vitro antagonistic assay of ZZ-21 culture, the strain exhibited an antifungal activity against R. solani in a dose-dependent manner. The culture filtrate could impair membrane integrity, possibly through membrane lipid peroxidation. ZZ-21 could secrete multiple extracellular enzymes and siderophores. According to a series of antifungal assays, the extracellular metabolites of ZZ-21 contained antimicrobial bioactive compounds composed of proteins/peptides extracted using ammonium sulfate precipitation, which were stable under stress caused by high temperature and protease K. The EC50 value for ammonium sulfate precipitation was determined to be 21.11 µg/mL in this study. Moreover, the proteins/peptides also exhibited biocontrol ability and were observed to alter the plasma membrane integrity of R. solani which were evaluated by biocontrol efficacy assays on detached tobacco leaves and PI staining. Overall, strain ZZ-21 shows the potential to be developed into a biopesticide against tobacco target spot disease.


Assuntos
Antifúngicos , Streptomyces , Antifúngicos/farmacologia , Sulfato de Amônio/farmacologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Rhizoctonia , Nicotiana , Peptídeos/farmacologia
20.
Environ Sci Technol ; 57(48): 20074-20084, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37974434

RESUMO

Efflorescence of ammonium nitrate (AN) aerosols significantly impacts atmospheric secondary aerosol formation, climate, and human health. We investigated the effect of representative water-soluble organic compounds (WSOCs) (sucralose (SUC), glycerol (GLY), and citric acid (CA) on AN:WSOC aerosol efflorescence using vacuum Fourier transform infrared spectroscopy. Combining efflorescence relative humidity (ERH) measurements, heterogeneous nucleation rates, and model predictions, we found that aerosol viscosity, correlating with molecular diffusion, effectively predicted ERH variations among the AN:WSOC aerosols. WSOCs with higher viscosity (SUC and CA) hindered efflorescence, while GLY with a lower viscosity showed a minor effect. At a low AN:CA molar ratio (10:1), CA promoted ERH, likely due to CA crystallization. Increasing the droplet pH inhibited AN:CA aerosol efflorescence. In contrast, for AN:SUC and AN:GLY aerosols, efflorescence is pH-insensitive. With the addition of trivial sulfate, AN:SUC droplets exhibited two-stage efflorescence, coinciding with ammonium sulfate and AN efflorescence. Given the atmospheric abundance, the morphology, phase, and mixing state of nitrate aerosols are significant for atmospheric chemistry and physics. Our results suggest that AN:WSOCs aerosols can exist in the amorphous phase in the atmosphere, with efflorescence behavior depending on the aerosol composition, viscosity, pH, and the cation and anion interactions in a complex manner.


Assuntos
Nitratos , Água , Humanos , Nitratos/química , Água/química , Umidade , Sulfato de Amônio/química , Aerossóis , Concentração de Íons de Hidrogênio
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