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1.
PLoS One ; 15(2): e0229141, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32084175

RESUMO

The objective was to evaluate the effect of the addition of 0, 10, 20, and 30 mg.kg-1 of natural matter of a lignocellulosic enzymatic complex produced by the white rot fungus on the chemical composition, cumulative gas production in vitro, and antioxidant compounds of corn and sugarcane silages. After being chopped and treated with the enzymatic complex, the plants were packed in vacuum-sealed bags. After 60 days, the mini silos were opened and the samples were dried in a forced ventilation oven at 55 °C for analysis of the proposed parameters. The experiment was conducted in a completely randomized design with four replicates per treatment. In the corn silage, there was a linear reduction in the lignin concentration. In the sugarcane silage showed a reduction of 12% in the lignin concentration, a linear reduction in the hemicellulose content, and a decrease of 8% in the cellulose concentration compared to the control treatment. The lignin monomers had linear increases in the syringyl:guaiacil ratio. This reflected on significant increases in the concentration of the non-fibrous carbohydrates and the A + B1 fraction of the carbohydrates, and a reduction in the C fraction. The in vitro gas production increased, the time of colonization and initiation of in vitro fermentation linearly decreased in both silages. The phenolic compounds and the antioxidant capacity increased linearly with the addition of the enzymes in both silages. The addition of the lignocellulolytic enzymes to the silages caused changes in the cell wall, resulting in improvements in the in vitro fermentative parameters, besides the additional effect on the antioxidant capacity. There was an effect of the addition of the enzymes on the evaluated fodder, and the best concentration was, on average, 20 mg kg-1 MN for corn silage and 10 mg kg-1 NM for sugarcane silage.


Assuntos
Antioxidantes/análise , Hidrolases/metabolismo , Lignina/análise , Pleurotus/metabolismo , Saccharum/metabolismo , Silagem/análise , Zea mays/metabolismo , Hidrolases/biossíntese , Hidrólise , Lignina/metabolismo
2.
J Chromatogr A ; 1609: 460505, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31500881

RESUMO

Biochemical and thermochemical processes are two pathways to convert lignocellulosic biomass into fuels and chemicals. Both conversion types produce aqueous complex samples containing many oxygenated chemical functions over a wide range of masses. Nowadays, composition of these biomass products is still largely unknown, especially their nonvolatile part (300-1000 Da) mostly made of carbohydrates and their derivatives. In the present study, size exclusion chromatography (SEC) was investigated and applied on water soluble phase of a fast pyrolysis bio-oil (thermochemical conversion) and on aqueous phase of pretreated wheat straw (biochemical conversion). An optimization of mobile phase composition using model molecules was necessary to limit non-steric interactions and elute all chemical families. At the end, separation of carbohydrates, heterosides and aromatic species was performed. The chemical organization of SEC chromatograms was confirmed by coupling SEC with a Fourier transform-ion cyclotron resonance mass spectrometer (FT-ICR MS) using electrospray ionization (ESI) in the negative mode. On-line SEC-UV/FT-ICR MS hyphenation was a powerful tool to provide exact mass distribution of samples and get molecular formulae classed by chemical family. To go further, the complementarity of SEC with reversed-phase liquid chromatography (RPLC) was established with an off-line comprehensive 2D-LC analysis of the two samples. First, 140 fractions were collected physically from SEC separation for each sample, then each fraction was analyzed by RPLC hyphenated to an Ion Trap - Time of Flight mass spectrometer (SEC × RPLC-UV/IT-TOF MS) using ESI in both positive and negative modes. This comprehensive approach combining 2D-LC and high resolution mass spectrometry nearly doubled the number of peaks detected in comparison with 1D RPLC analysis and thus offered well resolved 2D contour plots, considered as relevant analytical fingerprints of the aqueous phase of biomass samples.


Assuntos
Biomassa , Cromatografia em Gel , Cromatografia de Fase Reversa/métodos , Lignina/análise , Espectrometria de Massas/métodos , Cromatografia Líquida , Sistemas On-Line
3.
J Appl Microbiol ; 128(1): 161-170, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31609034

RESUMO

AIMS: The utilization of micro-organisms in pulp and paper industries has proved biobleaching technology as an environmentally friendly alternative to the conventional approach. In this paper, the effect of actinobacterial fermentation broth on pulp biobleaching has been investigated. METHODS AND RESULTS: Actinobacterial colonies were isolated from lignocellulose-rich soil samples and screened for xylanase production and bleaching activity. The most efficient isolate in bleaching activity showed 100% similarity to Streptomyces rutgersensis. Pulp treatment with 5-day fermentation broth of this strain showed up to 7% increase in brightness (30°C for 6 h, pH (5-7)) compared to untreated (control) pulp. Also, after 60 min biotreatment, significant reduction (12·5%) in consumption of bleaching chemicals was achieved to obtain final brightness of 55%. CONCLUSION: Actinobacterial fermentation broth can be considered as a rich source of effective biobleaching agents which may be considered as environmental friendly and cost-effective technique in comparison with traditional method. SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings showed ability of S. rutgersensis UTMC 2445 in bleaching chemomechanical paper pulp. Also, two strains of Saccharothrix, a rare actinobacterium, with biobleaching activity were introduced. In the proposed method, there is no need to use purified enzymes, and biobleaching process can be done using the fermentation broth.


Assuntos
Clareadores/metabolismo , Lignina/análise , Papel , Solo/química , Streptomyces/metabolismo , Actinomycetales/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Fermentação , Concentração de Íons de Hidrogênio , Lignina/metabolismo , Microbiologia do Solo , Streptomyces/enzimologia , Temperatura
4.
Food Chem ; 306: 125611, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606631

RESUMO

Aromatic secondary metabolites are closely related to quality attributes of postharvest fruit. In the present study, 20% CO2 was applied to strawberry fruit to investigate the regulation of elevated CO2 on aromatic secondary metabolites. The results showed that elevated CO2 delayed accumulations of anthocyanins, eugenol and lignin. Phenylalanine and tyrosine, the precursors of the above secondary metabolites, were 18.90% and 35.61%, respectively, lower in CO2-treated fruit compared with the control on day 6. Furthermore, enzyme activities and transcriptional profiles analysis showed pentose phosphate pathway and glycolysis were activated by elevated CO2 whereas the aromatic amino acids (AAAs) pathway was inhibited. These results indicated that elevated CO2 restricted carbon flux into aromatic secondary metabolism by inhibiting the AAAs pathway, leading to the decrease of phenylalanine and tyrosine, and thus, delayed the accumulation of aromatic secondary metabolites. In addition, the effect of elevated CO2 was eliminated after transferred CO2-treated fruit to air.


Assuntos
Fragaria/metabolismo , Antocianinas/análise , Antocianinas/metabolismo , Dióxido de Carbono/química , Eugenol/análise , Eugenol/metabolismo , Fragaria/química , Frutas/química , Frutas/metabolismo , Lignina/análise , Lignina/metabolismo
5.
J Dairy Sci ; 103(3): 2333-2346, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31882208

RESUMO

Accurate analysis of degradability of silage neutral detergent fiber (NDF) is important for diet formulation and to predict lactational performance of dairy cows. In this study, 5 corn silage hybrids ensiled for 0 (unfermented), 30, 60, 120, and 150 d were used to determine the effects of ensiling time on silage neutral detergent fiber degradability (NDFD) and to assess the relationships between near-infrared reflectance spectroscopy (NIR) NDF-related analyses and in situ NDFD variables. In addition, the relationships between dietary concentration of indigestible NDF, 288-h incubation (iNDF288), or undegraded NDF, 240-h incubation (uNDF240), and in vivo total-tract apparent organic matter and NDF digestibility were studied in total mixed ration samples from 16 experiments with lactating dairy cows. Ensiling time had no effect on silage NDF concentration; however, the ratio of acid detergent fiber ÷ NDF increased, and estimated hemicellulose concentration decreased quadratically with ensiling time. Also, concentration of NDF-bound protein decreased, and that of lignin increased linearly with ensiling time. These changes in silage fiber composition resulted in a linear decrease in in situ effective degradability of silage NDF with increasing ensiling time. The indigestible fraction of NDF and concentration of structural carbohydrates were not affected by ensiling time. Correlations of in situ NDFD variables with laboratory NIR NDFD analyses were weak to moderate. The relationship of corn silage uNDF240 with lignin concentration or 30-h NDFD (all NIR analyses) was remarkably good (R2 = 0.73 and 0.88, respectively). The relationship between in situ iNDF288 concentration (but not uNDF240) and in vivo total-tract apparent digestibility of dietary organic matter and NDF was good (R2 = 0.72 and 0.80, respectively). In conclusion, in situ degradability of silage NDF linearly decreased from 0 to 150 d ensiling time, primarily caused by a decrease in concentrations of hemicellulose and NDF-bound protein. In situ NDF degradability measurements and common laboratory NIR NDF-related analyses were generally poorly correlated. We found a good relationship between in vivo NDF digestibility and dietary concentration of iNDF288 determined in situ, but the relationship with uNDF240 was poor.


Assuntos
Bovinos/fisiologia , Fibras na Dieta/análise , Silagem/análise , Zea mays , Animais , Detergentes , Dieta/veterinária , Fibras na Dieta/metabolismo , Digestão , Feminino , Lactação , Lignina/análise , Lignina/metabolismo , Rúmen/metabolismo , Fatores de Tempo
6.
Molecules ; 24(23)2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783525

RESUMO

A series of ferric chloride-lignin sulfonate (FCLS) was prepared from ferric chloride and lignin sulfonate to be used as shale inhibitor. The swelling rate of clay with FCLS-2 (w/w = 0.3%) decreased to 41.9%. Compared with control, FCLS-2 displayed high inhibitive ability against the hydrating and swelling processes of clay. Thus, the swelling degree of samples with FCLS-2 was much lower than that of the control, as well as the mud ball was more stable in FCLS-2 solution. Essentially, these excellent performances in inhibitor were assigned to the hydrogen bonding, electrostatic interaction and anchoring between FCLS-2 and other components. In addition, FCLS-2 has good compatibility with other common drilling fluid additives, and it can reduce the viscosity of systems, regardless of the room temperature or high temperature.


Assuntos
Cloretos/química , Compostos Férricos/química , Lignina/química , Bentonita/antagonistas & inibidores , Bentonita/química , Cloretos/análise , Argila/química , Compostos Férricos/análise , Lignina/análise , Lignina/síntese química , Microscopia Eletrônica de Varredura , Minerais , Gás Natural , Indústria de Petróleo e Gás , Tamanho da Partícula , Petróleo , Ácidos Sulfônicos/química , Termogravimetria , Viscosidade
7.
Proc Natl Acad Sci U S A ; 116(36): 17900-17905, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31427536

RESUMO

A comparison of sequenced Agaricomycotina genomes suggests that efficient degradation of wood lignin was associated with the appearance of secreted peroxidases with a solvent-exposed catalytic tryptophan. This hypothesis is experimentally demonstrated here by resurrecting ancestral fungal peroxidases, after sequence reconstruction from genomes of extant white-rot Polyporales, and evaluating their oxidative attack on the lignin polymer by state-of-the-art analytical techniques. Rapid stopped-flow estimation of the transient-state constants for the 2 successive one-electron transfers from lignin to the peroxide-activated enzyme (k 2app and k 3app ) showed a progressive increase during peroxidase evolution (up to 50-fold higher values for the rate-limiting k 3app ). The above agreed with 2-dimensional NMR analyses during steady-state treatments of hardwood lignin, showing that its degradation (estimated from the normalized aromatic signals of lignin units compared with a control) and syringyl-to-guaiacyl ratio increased with the enzyme evolutionary distance from the first peroxidase ancestor. More interestingly, the stopped-flow estimations of electron transfer rates also showed how the most recent peroxidase ancestors that already incorporated the exposed tryptophan into their molecular structure (as well as the extant lignin peroxidase) were comparatively more efficient at oxidizing hardwood (angiosperm) lignin, while the most ancestral "tryptophanless" enzymes were more efficient at abstracting electrons from softwood (conifer) lignin. A time calibration of the ancestry of Polyporales peroxidases localized the appearance of the first peroxidase with a solvent-exposed catalytic tryptophan to 194 ± 70 Mya, coincident with the diversification of angiosperm plants characterized by the appearance of dimethoxylated syringyl lignin units.


Assuntos
Evolução Biológica , Fungos/genética , Lignina/metabolismo , Peroxidase/genética , Plantas/metabolismo , Plantas/microbiologia , Madeira/metabolismo , Madeira/microbiologia , Catálise , Fungos/enzimologia , Hidrólise , Cinética , Lignina/análise , Oxirredução , Peroxidase/metabolismo , Plantas/genética , Madeira/análise
8.
Nat Commun ; 10(1): 3418, 2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31366935

RESUMO

Oil produced by castor (Ricinus communis) has broad industrial applications. However, knowledge on the genetic diversity, especially genetic alterations that occurred during domestication and subsequent traits selection, of this oil crop is limited. Here, our population genomics analyses show that the Chinese castors have developed a geographic pattern, classified into the southern-, the middle-, and the northern-China groups. We detect a number of candidate genomic loci that are associated with the selection signals during the geographical differentiation and domestication. Using genome-wide association analysis, we identify candidate genes associated with nine agronomically important traits. One of the candidate genes encoding a glycosyltransferase related to cellulose and lignin biosynthesis is associated with both capsule dehiscence and endocarp thickness. We hypothesize that the abundance of cellulose or lignin in endocarp is an important factor for capsule dehiscence. Our results provide foundation for castor breeding and genetic study.


Assuntos
Frutas/genética , Frutas/fisiologia , Genoma de Planta/genética , Óleos Vegetais/química , Ricinus/genética , Celulose/análise , China , Estudo de Associação Genômica Ampla , Geografia , Glicosiltransferases/genética , Lignina/análise , Ricinus/química , Seleção Genética/genética
9.
Ultrason Sonochem ; 58: 104631, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31450383

RESUMO

The study focused on inhibiting microorganism and improving preservation of green asparagus (Asparagus officinalis L.) during cold storage. Green asparagus is treated with ultrasound (US), acetic acid and gibberellin acid (AG) separately as well as combination (US + AG) and then stored at 4 °C for 20 days. Microorganism, physicochemical qualities and sensory characteristics were monitored at regular intervals. Results showed that the US treatment significantly (p < 0.05) reduced the total number of colonies, mold and yeast merely in the 12th and 16th day of storage, while the US + AG treatment not only achieved an effective decontamination (up to 2 log reduction) of green asparagus throughout the storage, but also retained the physicochemical characteristics to a higher level in comparison to other treatments. The US + AG treatment exhibited lower weight loss, higher levels of total soluble solid (TSS), ascorbic acid, chlorophyll content and total phenolic content (TPC), as well as kept better sensory attributes. Moreover, the US + AG treatment significantly inhibited the activities of phenylalanine ammonia lyase (PAL) and peroxidase (POD) (p < 0.05), suppressing the biosynthesis of lignin. These results suggested that the US + AG treatment could be a potential strategy to preserve quality of green asparagus during cold storage.


Assuntos
Asparagus (Planta)/microbiologia , Temperatura Baixa , Qualidade dos Alimentos , Armazenamento de Alimentos , Ondas Ultrassônicas , Verduras/microbiologia , Ácido Ascórbico/análise , Asparagus (Planta)/química , Clorofila/análise , Lignina/análise , Fenol/análise , Paladar , Verduras/química
10.
Nat Protoc ; 14(9): 2627-2647, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31391578

RESUMO

The analysis of chemical structural characteristics of biorefinery product streams (such as lignin and tannin) has advanced substantially over the past decade, with traditional wet-chemical techniques being replaced or supplemented by NMR methodologies. Quantitative 31P NMR spectroscopy is a promising technique for the analysis of hydroxyl groups because of its unique characterization capability and broad potential applicability across the biorefinery research community. This protocol describes procedures for (i) the preparation/solubilization of lignin and tannin, (ii) the phosphitylation of their hydroxyl groups, (iii) NMR acquisition details, and (iv) the ensuing data analyses and means to precisely calculate the content of the different types of hydroxyl groups. Compared with traditional wet-chemical techniques, the technique of quantitative 31P NMR spectroscopy offers unique advantages in measuring hydroxyl groups in a single spectrum with high signal resolution. The method provides complete quantitative information about the hydroxyl groups with small amounts of sample (~30 mg) within a relatively short experimental time (~30-120 min).


Assuntos
Lignina/análise , Lignina/química , Espectroscopia de Ressonância Magnética/métodos , Panicum/química , Fósforo/química , Pinus/química , Populus/química , Taninos/análise , Taninos/química
11.
Food Chem ; 298: 125032, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260968

RESUMO

A dietary fibre prepared from sugarcane stalk was compared with psyllium husk and wheat dextrin. In contrast to the other dietary fibres, sugarcane fibre was found to contain significant amounts of insoluble dietary fibre (73-86%), lignin (18.66-20.23%), and rare minerals such as chromium (0.67-2.54 mg/100 g) and manganese (1.07-2.34 mg/100 g). Analysis of the ethanol extract also detected compounds with antioxidant activity. Characterisation of five sugarcane fibres prepared from selected strains, harvest periods (growth or storage phase), and processing conditions showed these factors influenced the final composition. Furthermore, using in vitro digestion, we found that potassium, magnesium, chromium, and zinc in were bioaccessible in sugarcane samples. Also, sodium was shown to bind to the sugarcane fibre potentially indicating bile salt binding activity. Results from this study support the use of sugarcane as a source of dietary fibre in functional foods.


Assuntos
Dextrinas/química , Fibras na Dieta/análise , Plantago/química , Saccharum/química , Triticum/química , Antioxidantes/análise , Cromo/análise , Cromo/farmacocinética , Dextrinas/análise , Fibras na Dieta/metabolismo , Indústria de Processamento de Alimentos/métodos , Lignina/análise , Metais/análise , Metais/farmacocinética
12.
Methods Mol Biol ; 1992: 27-42, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148029

RESUMO

Histochemical methods allow for identification and localization of various components within the tissue. Such information on the spatial heterogeneity is not available with biochemical methods. However, there is limitation of the specificity of such detection in context of complex tissue, which is important to consider, and interpretations of the results should regard suitable control treatments if possible. Such methods are valuable extension to specific optical and spectroscopic analytical methods. Here we present a set of selected simple methods of staining and histochemical tests with comments based on our laboratory experience.


Assuntos
Parede Celular/química , Microscopia/métodos , Plantas/química , Coloração e Rotulagem/métodos , Parede Celular/ultraestrutura , Celulose/análise , Corantes/análise , Histocitoquímica/métodos , Lignina/análise , Lipídeos/análise , Pectinas/análise , Plantas/ultraestrutura
13.
Methods Mol Biol ; 1992: 77-82, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148032

RESUMO

Fluorescence is a versatile property of many molecules called fluorophores. In plant cell walls, fluorescence is generally attributed to aromatic molecules such as lignin. In contrary to fluorescence intensity, fluorescence lifetime is independent from fluorophore concentration. So mapping fluorescence lifetime of plant cell walls represents a complementary approach to acquire chemical and structural information of cell wall components and interactions.


Assuntos
Parede Celular/ultraestrutura , Microscopia de Fluorescência/métodos , Imagem Óptica/métodos , Plantas/ultraestrutura , Parede Celular/química , Lignina/análise , Plantas/química
14.
Methods Mol Biol ; 1992: 83-107, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148033

RESUMO

Confocal Raman spectroscopy (RS) enables obtaining molecular information from the nondestructive analysis of plant material in situ. It can thereby be a useful method to investigate spatial distribution and heterogeneity of cell-wall polymers. The authors' intention is to present some examples of RS application and its capabilities for investigations of nonwoody plants. In this context, we present protocols for qualitative analysis of main polymers of plant wall and application of RS in a semiquantitative study of the arrangement of selected polymers in the wall in its native state.


Assuntos
Parede Celular/química , Plantas/química , Análise Espectral Raman/métodos , Parede Celular/ultraestrutura , Celulose/análise , Processamento de Imagem Assistida por Computador/métodos , Lignina/análise , Microscopia Confocal/métodos , Imagem Óptica/métodos , Pectinas/análise , Plantas/ultraestrutura , Software
15.
Molecules ; 24(9)2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31035593

RESUMO

This review is a summary of the Raman spectroscopy applications made over the last 10 years in the field of cellulose and lignocellulose materials. This paper functions as a status report on the kinds of information that can be generated by applying Raman spectroscopy. The information in the review is taken from the published papers and author's own research-most of which is in print. Although, at the molecular level, focus of the investigations has been on cellulose and lignin, hemicelluloses have also received some attention. The progress over the last decade in applying Raman spectroscopy is a direct consequence of the technical advances in the field of Raman spectroscopy, in particular, the application of new Raman techniques (e.g., Raman imaging and coherent anti-Stokes Raman or CARS), novel ways of spectral analysis, and quantum chemical calculations. On the basis of this analysis, it is clear that Raman spectroscopy continues to play an important role in the field of cellulose and lignocellulose research across a wide range of areas and applications, and thereby provides useful information at the molecular level.


Assuntos
Celulose/análise , Lignina/análise , Análise Espectral Raman , Celulose/química , Lignina/química , Estrutura Molecular , Nanocompostos/análise , Nanocompostos/química , Nanoestruturas/análise , Nanoestruturas/química , Polissacarídeos/análise , Polissacarídeos/química , Análise Espectral Raman/métodos
16.
PLoS One ; 14(5): e0217435, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31120985

RESUMO

Sudangrass, Sorghum sudanense (Piper) Stapf, is a vigorous forage crop that has also been used for biogas, paper, and electricity production. Due to the large biomass yields achieved by sudangrass and the large area of potential growth in Argentina seven sudangrass accessions from a collection of S. sudanense were analyzed to evaluate their potential as feedstocks for lignocellulosic bioethanol production, and to assess whether there is an association between the response to biotic and abiotic stresses and the composition of the biomass. The biomass composition was analyzed for major cell wall polymers, monosaccharides, and elemental composition. On average, 68% of stem lignocellulosic biomass was comprised of matrix polysaccharides and crystalline cellulose, representing a potential source of sugars for bioethanol production. Xylose was the predominant matrix polysaccharide monosaccharide comprising, on average, 45% of the total sugars, followed by arabinose, glucose, galactose, galacturonic acid, mannose, glucuronic acid, and fucose. Rhamnose was not detected in any of the biomasses analyzed. Silica was the most abundant element in sudangrass stem, followed by chloride, calcium, phosphorus and sulfur. We performed saccharification analyses after pretreatments. Alkaline pretreatment was more effective than water pretreatment. Sodium hydroxide pretreatment exposed different levels of recalcitrance among sudangrass accessions, whereas the water pretreatment did not. Phenological traits were also evaluated, showing significant variability among accessions. The comparison of major cell wall polymers and monosaccharide composition between tolerant and susceptible accessions to abiotic and biotic stresses suggests an association between the composition of the biomass and the response to stress.


Assuntos
Fontes de Energia Bioelétrica , Biomassa , Etanol/metabolismo , Lignina/metabolismo , Sorghum/fisiologia , Argentina , Parede Celular/química , Parede Celular/metabolismo , Lignina/análise , Monossacarídeos/análise , Monossacarídeos/metabolismo , Polissacarídeos/análise , Polissacarídeos/metabolismo , Sorghum/química , Estresse Fisiológico
17.
J Sep Sci ; 42(13): 2289-2297, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31106519

RESUMO

Depolymerized lignin products are very complex mixtures. Based on a depolymerization solution of commercially available sodium lignosulfonate under mild conditions, a fast and efficient method for the separation and direct characterization of the degree and efficiency of the acid-catalyzed depolymerization of lignin was developed in this study. Using an ultraviolet detector, the depolymerized lignosulfonate products were well separated and characterized according to the relative molar mass distribution on an advanced polymer chromatographic system with three ethylene-bridged hybrid columns having small pore sizes (45 Å) in series and tetrahydrofuran as the mobile phase. The developed advanced polymer chromatography method enabled the detection of low-molecular-weight lignin degradation products (Mn  = 260-1100 Da) with high peak resolutions in less than 7.2 min. Furthermore, preliminary advanced polymer chromatography studies to determine the influence of reaction temperature on the depolymerized products indicated that the depolymerized aromatics fell in several molecular weight ranges with an extremely low dispersity. This new approach can be used for the rapid analysis of lignin depolymerization products.


Assuntos
Lignina/análogos & derivados , Polímeros/química , Cromatografia Líquida de Alta Pressão , Lignina/análise , Lignina/síntese química , Polimerização
18.
Poult Sci ; 98(10): 4745-4754, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31002110

RESUMO

Two experiments were conducted to evaluate the effects of different types and levels of mixer-added fat (soybean oil: SO and calcium fat powder: CFP) and pellet binders (PBs: calcium lignosulfonate (CaLS) and bentonite (Ben)) on physical pellet quality (PPQ) parameters. PPQ included pellet durability index (PDI), pellet hardness, and pellet length of broiler diets processed under short-term conditioning. The first experiment had 4 treatments arranged as a 2 × 2 factorial with 2 types (SO and CFP) and 2 levels (1.5 and 3%) of mixer-added fat. In the second experiment, 22 treatments, combinations of 2 types of mixer-added fat (SO and CFP) at 3 levels (0, 1.5 and 3%) and 2 types of PB (CaLS = 0, 0.5, and 1% and Ben = 0, 1, and 2%), were arranged by a completely randomized design. PDI was measured by 2 devices: Pfost Tumbling box (PDIT) and Holmen NHP tester (PDIH). The results showed that the diets containing 1.5% CFP without PB had significant differences in all PPQ parameters. The results revealed that adding 0.5% CaLS to the 3% SO diets significantly enhanced PDIH, pellet hardness, and pellet length compared to other treatments. Moreover, 1.5% CFP diets with 2% Ben had significantly higher PDIT, PDIH, and pellet hardness among the treatments. Based on contour plots, different levels of Ben in the diets containing SO failed to create optimum PDIT values (>96%). However, 1.5 to 2.50% CFP diets without Ben had the optimum PDIT values. The optimum PDIT value was achieved by the diets containing 3% SO in the range of 0.21 to 0.56% CaLS. Furthermore, adding 0.5% CaLS to the diets containing less than 2.86% SO resulted in suboptimal PDIT values (<96%). The diets containing 1.5 to 2.50% CFP without CaLS had the optimum PDIT values. However, increasing CaLS levels more than 0.38% led to suboptimal PDIT values. Overall, these results indicated that the selection of appropriate PBs should be based on type and level of mixer-added fat.


Assuntos
Ração Animal/análise , Bentonita/análise , Galinhas , Dieta/veterinária , Gorduras na Dieta/análise , Lignina/análogos & derivados , Animais , Cálcio/análise , Lignina/análise , Pós/análise , Óleo de Soja/análise
19.
Int J Mol Sci ; 20(6)2019 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-30884876

RESUMO

Artificial light at night (ALAN) is an increasing phenomenon worldwide that can cause a series of biological and ecological effects, yet little is known about its potential interaction with other stressors in aquatic ecosystems. Here, we tested whether the impact of lead (Pb) on litter decomposition was altered by ALAN exposure using an indoor microcosm experiment. The results showed that ALAN exposure alone significantly increased leaf litter decomposition, decreased the lignin content of leaf litter, and altered fungal community composition and structure. The decomposition rate was 51% higher in Pb with ALAN exposure treatments than in Pb without ALAN treatments, resulting in increased microbial biomass, ß-glucosidase (ß-G) activity, and the enhanced correlation between ß-G and litter decomposition rate. These results indicate that the negative effect of Pb on leaf litter decomposition in aquatic ecosystems may be alleviated by ALAN. In addition, ALAN exposure also alters the correlation among fungi associated with leaf litter decomposition. In summary, this study expands our understanding of Pb toxicity on litter decomposition in freshwater ecosystems and highlights the importance of considering ALAN when assessing environmental metal pollutions.


Assuntos
Água Doce/análise , Água Doce/microbiologia , Chumbo/toxicidade , Iluminação , Biomassa , Ecossistema , Poluição Ambiental/efeitos adversos , Poluição Ambiental/análise , Fungos/efeitos dos fármacos , Fungos/genética , Fungos/isolamento & purificação , Fungos/efeitos da radiação , Hidrólise/efeitos dos fármacos , Hidrólise/efeitos da radiação , Iluminação/efeitos adversos , Iluminação/métodos , Lignina/análise , Metagenômica , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Folhas de Planta/efeitos da radiação
20.
Carbohydr Polym ; 212: 160-168, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30832843

RESUMO

Environmental considerations in recent times have led to increasing interest in naturally occurring lignocellulosic materials as they are abundant and biodegradable. Pearl Millet (PM) stalks are currently discarded in North India and add to agrowaste generation. In this study, raw stalk of PM was characterized for physicochemical properties such as composition, moisture content, water absorbency and thermal behaviour. Morphology and crystallinity were studied using scanning electron microscope and X-ray diffraction respectively. Pure cellulose, extracted from the stalk using an optimised process, was characterised similarly. XRD patterns indicate the presence of cellulose type I structure with crystallinity index of 32% for raw stalk and 55% for the purified material. Water absorbency was 10 g/g for raw and 13 g/g for extracted cellulose. Material was thermally stable up to 200 °C. These findings indicate that PM stalks may be used as an indigenous source of cellulose for the absorbent layer in hygiene products.


Assuntos
Celulose/química , Lignina/química , Pennisetum , Extratos Vegetais/química , Celulose/análise , Celulose/isolamento & purificação , Cristalização/métodos , Lignina/análise , Lignina/isolamento & purificação , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação
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