Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 439
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Agric Food Chem ; 68(7): 2016-2023, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31986021

RESUMO

The protein precipitation (PP) of bovine serum albumin (BSA), lysozyme (LYS), and alfalfa leaf protein (ALF) by four procyanidin-rich condensed tannin (CT) samples in both 2-[N-morpholino]ethanesulfonic acid (MES) and a modified Goering-Van Soest (GVS) buffer is described. Purified CT samples examined included Vitis vinifera seed (mean degree of polymerization [mDP] 4.1, 16.5% galloylated), Tilia sp. flowers (B-type linkages, mDP 5.9), Vaccinium macrocarpon berries (mDP 8.7, 31.7% A-type linkages). and Trifolium pratense flowers (B-type linkages, mDP 12.3) and were characterized by 2D NMR (>90% purity). In general, CTs precipitated ALF > LYS ≥ BSA. PP in GVS buffer was 1 to 2.25 times greater than that in MES buffer (25 °C). The GVS buffer system better reflects the results/conclusions from the literature on the impacts mDP, galloylation, and A-type linkages have on PP. Determinations of PP using the MES buffer at 37 °C indicated that some of these differences may be attributed to the temperature at which GVS buffer determinations are conducted. In vitro PP studies using the GVS buffer may offer better guidance when selecting CT-containing forages and amendments for ruminant feeding studies.


Assuntos
Biflavonoides/química , Catequina/química , Extratos Vegetais/química , Proteínas de Plantas/química , Proantocianidinas/química , Soroalbumina Bovina/química , Ração Animal/análise , Tampões (Química) , Precipitação Química , Medicago sativa/química , Muramidase/química , Tilia/química , Vaccinium macrocarpon/química , Vitis/química
2.
J Sci Food Agric ; 100(5): 1922-1930, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31846083

RESUMO

BACKGROUND: Ten varieties of alfalfa (Medicago sativa L.) were evaluated for saponin content. Two of the most promising varieties were chosen so that their effect on rumen fermentation and methane production could be studied. Initially, four Hohenheim gas tests (HGT) were performed to test the effect of increased levels of total saponin extracted from the two alfalfa cultivars (Kometa and Verko) - either as fresh material or ensiled - on the total bacteria, total protozoa, methane emission, and selected methanogenic population. Afterwards, seven particular saponins were extracted from fresh alfalfa of the Kometa variety and tested in 24 h batch fermentation culture experiments. RESULTS: The ensiled forms of both the Verko and Kometa alfalfa varieties seem to be good sources of saponin, capable of reducing methane production (P < 0.05) without negatively affecting the basic fermentation parameters. Of the two evaluated varieties, Kometa was the most effective, and the saponins extracted from its roots 3-Glc,28-Glc Ma, medicagenic saponin, and 3-Glu Ma showed the most evident effect (P = 0.0001). The most promising aerial alfalfa saponin in mitigating methane production was soysaponin I K salt (P = 0.0001). Three mixtures of saponins were tested and all were found to mitigate methane production; however, one mixture (MIX 1) did so only to a very small extent. CONCLUSION: Saponins have been observed to have differing effects depending on their source; however, the mode of action of saponins depends on their direct or probable indirect effect on the microorganisms involved in methane production. © 2019 Society of Chemical Industry.


Assuntos
Bovinos/metabolismo , Medicago sativa/metabolismo , Metano/metabolismo , Rúmen/metabolismo , Saponinas/metabolismo , Ração Animal/análise , Animais , Digestão , Fermentação , Medicago sativa/química , Metano/análise , Saponinas/análise
3.
J Sci Food Agric ; 100(1): 431-440, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31598969

RESUMO

BACKGROUND: Sound waves are emerging as a potential biophysical alternative to traditional methods for enhancing plant growth and phytochemical contents. However, little information is available on the improvement of the concentration of functional metabolites like flavonoids in sprouts using sound waves. In this study, different frequencies of sound waves with short and long exposure times were applied to three important varieties to improve flavonoid content. The aim of this study was to investigate the effect of sound waves on flavonoid content on the basis of biochemical and molecular characteristics. RESULTS: We examined the effects of various sound wave treatments (250 Hz to 1.5 kHz) on flavonoid production in alfalfa (Medicago sativa), broccoli (Brassica oleracea) and red young radish (Raphanus sativus). The results showed that sound wave treatments differentially altered the total flavonoid contents depending upon the growth stages, species and frequency of and exposure time to sound waves. Sound wave treatments of alfalfa (250 Hz), broccoli sprouts (800 Hz) and red young radish sprouts (1 kHz) increased the total flavonoid content by 200%, 35% and 85%, respectively, in comparison with untreated control. Molecular analysis showed that sound waves induce the expression of genes of the flavonoid biosynthesis pathway, which positively corresponds to the flavonoid content. Moreover, the sound wave treatment significantly improves the antioxidant efficiency of sprouts. CONCLUSIONS: The significant improvement of flavonoid content in sprouts with sound waves makes their use a potential and promising technology for the production of agriculture-based functional foods. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Brassica/efeitos da radiação , Flavonoides/química , Medicago sativa/efeitos da radiação , Raphanus/efeitos da radiação , Brassica/química , Brassica/crescimento & desenvolvimento , Medicago sativa/química , Medicago sativa/crescimento & desenvolvimento , Raphanus/química , Raphanus/crescimento & desenvolvimento , Som
4.
Int J Food Microbiol ; 312: 108374, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31669765

RESUMO

Salmonella enterica outbreaks in sprouts originate from contaminated seeds; conventional prevention technologies have been reported from many research institutes. In this study, we applied a biological control approach to inhibit S. enterica growth using the seed-dwelling non-antagonistic bacteria. We isolated non-antibacterial seed-dwelling bacteria from vegetable sprouts. A total of 206 bacteria exhibiting non-antibacterial activity against S. enterica were subjected to alfalfa sprout development tests. Eight isolates exhibiting no deleterious effect on the growth of alfalfa sprouts were tested for S. enterica growth inhibition on alfalfa seeds and sprouts, and an isolate EUS78 was finally selected for further investigation. Based on 16S rRNA, gyrB, and rpoB gene sequence analyses, strain EUS78 was identified as Erwinia persicina. In population competition, the S. enterica population increased by >3 log CFU/g after 6 days of alfalfa sprout growth, whereas S. enterica growth was significantly inhibited by treatment with EUS78 (P < .05). This effect of S. enterica growth inhibition by EUS78 was sustained until the end of the alfalfa sprout harvest. Overall, bacterial strain EUS78 significantly reduced S. enterica growth on alfalfa sprouts in a manner consistent with competitive exclusion. These findings led us to monitor EUS78 behavior on seeds during early sprout development using fluorescence and scanning electron microscopy. Strain EUS78 initially colonized alfalfa sprout seed coat edges, cotyledons, and finally root surfaces during early sprout germination. As alfalfa sprouts grew, EUS78 bacterial cells established colonies on newly emerged plant tissues such as root tips. The results of this study suggest that strain EUS78 has potential as a biological control agent to inhibit S. enterica contamination in the sprout food industry.


Assuntos
Antibiose/fisiologia , Agentes de Controle Biológico , Erwinia/fisiologia , Medicago sativa/microbiologia , Salmonella enterica/crescimento & desenvolvimento , Sementes/microbiologia , DNA Girase/genética , RNA Polimerases Dirigidas por DNA/genética , Erwinia/genética , Microbiologia de Alimentos , Indústria de Processamento de Alimentos , Germinação/fisiologia , Medicago sativa/química , RNA Ribossômico 16S/genética , Verduras/microbiologia
5.
Food Chem ; 309: 125786, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31704078

RESUMO

The ultrasonic-assisted extraction of total saponins from alfalfa leaves was optimised by the simultaneous maximization of the yield and bioaccessibility as a factor with increasingly great relevance in the biological activity by Response Surface Methodology. The kinetics of total saponins and bioaccessibility were investigated for the optimum ultrasound-assisted method compared to conventional method by the pseudo-first order model. The optimum extraction conditions were of solvent/raw material ratio of 11.4 mL/g, extraction time of 2.84 h, extraction temperature of 76.8 °C, ultrasound power of 112.0 w and ethanol concentration of 78.2%. The yield of total saponins and bioaccessibility was 1.61 and 18.6%, respectively. The yield rate constant for the ultrasound extraction was almost two times more than that of the heat-reflux method. Ultrasonic-assisted extraction, comparing to conventional method, had greater efficiency for the extraction yield and bioaccessibility of total saponins.


Assuntos
Medicago sativa/química , Saponinas/análise , Sonicação , Etanol/química , Cinética , Medicago sativa/metabolismo , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Saponinas/isolamento & purificação , Solventes/química
6.
ACS Appl Mater Interfaces ; 11(37): 33535-33547, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31369233

RESUMO

Engineering bioscaffolds for improved cutaneous tissue regeneration remains a healthcare challenge because of the increasing number of patients suffering from acute and chronic wounds. To help address this problem, we propose to utilize alfalfa, an ancient medicinal plant that contains antibacterial/oxygenating chlorophylls and bioactive phytoestrogens, as a building block for regenerative wound dressings. Alfalfa carries genistein, which is a major phytoestrogen known to accelerate skin repair. The scaffolds presented herein were built from composite alfalfa and polycaprolactone (PCL) nanofibers with hydrophilic surface and mechanical stiffness that recapitulate the physiological microenvironments of skin. This composite scaffold was engineered to have aligned nanofibrous architecture to accelerate directional cell migration. As a result, alfalfa-based composite nanofibers were found to enhance the cellular proliferation of dermal fibroblasts and epidermal keratinocytes in vitro. Finally, these nanofibers exhibited reproducible regenerative functionality by promoting re-epithelialization and granulation tissue formation in both mouse and human skin, without requiring additional proteins, growth factors, or cells. Overall, these findings demonstrate the potential of alfalfa-based nanofibers as a regenerative platform toward accelerating cutaneous tissue repair.


Assuntos
Derme , Queratinócitos , Medicago sativa/química , Nanocompostos , Nanofibras , Cicatrização/efeitos dos fármacos , Linhagem Celular , Derme/lesões , Derme/metabolismo , Derme/patologia , Humanos , Queratinócitos/metabolismo , Queratinócitos/patologia , Nanocompostos/química , Nanocompostos/uso terapêutico , Nanofibras/química , Nanofibras/uso terapêutico , Poliésteres/química
7.
J Anim Sci ; 97(9): 3994-4009, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31372657

RESUMO

Diverse combinations of forages with different nutrient profiles and plant secondary compounds may improve intake and nutrient utilization by ruminants. We tested the influence of diverse dietary combinations of tannin- (sainfoin-Onobrichis viciifolia; birdsfoot trefoil-Lotus corniculatus) and non-tannin- (alfalfa-Medicago sativa L.) containing legumes on intake and diet digestibility in lambs. Freshly cut birdsfoot trefoil, alfalfa, and sainfoin were offered in ad libitum amounts to 42 lambs in individual pens assigned to 7 treatments (6 animals/treatment): 1) single forage species (sainfoin [SF], birdsfoot trefoil [BFT], and alfalfa [ALF]), 2) all possible 2-way choices of the 3 forage species (alfalfa-sainfoin [ALF-SF], alfalfa-birdsfoot trefoil [ALF-BFT], and sainfoin-birdsfoot trefoil [SF-BFT]), or 3) a choice of all 3 forages (alfalfa-sainfoin-birdsfoot trefoil [ALF-SF-BFT]). Dry matter intake (DMI) was greater in ALF than in BFT (P = 0.002), and DMI in SF tended to be greater than in BFT (P = 0.053). However, when alfalfa was offered in a choice with either of the tannin-containing legumes (ALF-SF; ALF-BFT), DMI did not differ from ALF, whereas DMI in SF-BFT did not differ from SF (P > 0.10). When lambs were allowed to choose between 2 or 3 legume species, DMI was greater (36.6 vs. 33.2 g/kg BW; P = 0.038) or tended to be greater (37.4 vs. 33.2 g/kg BW; P = 0.067) than when lambs were fed single species, respectively. Intake did not differ between 2- or 3-way choice treatments (P = 0.723). Lambs preferred alfalfa over the tannin-containing legumes in a 70:30 ratio for 2-way choices, and alfalfa > sainfoin > birdsfoot trefoil in a 53:33:14 ratio for the 3-way choice. In vivo digestibility (DMD) was SF > BFT (72.0% vs. 67.7%; P = 0.012) and DMD in BFT tended to be greater than in ALF (64.6%; P = 0.061). Nevertheless, when alfalfa was offered in a choice with either sainfoin or birdsfoot trefoil (ALF-SF; ALF-BFT), DMD was greater than ALF (P < 0.001 and P = 0.007, respectively), suggesting positive associative effects. The SF treatment had lower blood urea nitrogen and greater fecal N/N intake ratios than the ALF, BFT, or ALF-BFT treatments (P < 0.05), implying a shift in the site of N excretion from urine to feces. In conclusion, offering diverse combinations of legumes to sheep enhanced intake and diet digestibility relative to feeding single species, while allowing for the incorporation of beneficial bioactive compounds like condensed tannins into the diet.


Assuntos
Ração Animal/análise , Ingestão de Alimentos , Fabaceae/química , Nitrogênio/metabolismo , Ovinos/fisiologia , Taninos/metabolismo , Animais , Dieta/veterinária , Digestão , Fezes/química , Lotus/química , Medicago sativa/química , Folhas de Planta/química
8.
J Agric Food Chem ; 67(28): 7898-7907, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31282664

RESUMO

This study aimed to explore the effects of silencing HB12 and TT8 genes on protein utilization characteristics of alfalfa. Ground samples of 11 HB12-silenced (HB12i), 5 TT8-silenced (TT8i) and 4 wild type (WT) were incubated in a Daisy II incubator with N15 labeled ammonium sulfate for 0, 4, 8, 12, and 24 h. CP degradation and degradational kinetics, microbial nitrogen fractions, and protein metabolic profiles were determined. Moreover, relationships between protein profiles and FTIR spectral parameters were estimated. Results showed that transgenic alfalfa had lower CP degradation, microbial protein, and total available protein compared with WT, especially for HB12i. In addition, CP degradation and protein metabolic profiles were closely correlated with FTIR spectral parameters and thereby could be predicted from spectral parameters. In conclusion, silencing of HB12 and TT8 genes in alfalfa decreased protein degradational and metabolic profiles, which were predictable with FTIR spectral parameters.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Inativação Gênica , Proteínas de Homeodomínio/genética , Medicago sativa/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Rúmen/metabolismo , Ração Animal/análise , Animais , Bactérias/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Bovinos , Digestão , Proteínas de Homeodomínio/metabolismo , Cinética , Medicago sativa/química , Medicago sativa/metabolismo , Proteínas de Plantas/química , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Proteólise , Rúmen/química , Rúmen/microbiologia
9.
J Appl Microbiol ; 127(4): 985-995, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31287933

RESUMO

AIMS: Ferulic acid esterase (FAE)-producing Lactobacillus species isolated from ensiled Elymus nutans growing on the Qinghai-Tibetan plateau were characterized, and effects of their application to the alfalfa ensiling process and the evidence to synergic effect between cellulase and FAE were investigated. METHODS AND RESULTS: The results of 16S rRNA gene sequence and species-specific polymerase chain reaction amplification showed that two screened strains with high FAE activity were Lactobacillus plantarum A1 (LP) and L. brevis A3 (LBr). The optimum temperature and pH for the LP and LBr was 37°C and 6·4 respectively. The FAE exhibited a good stability at temperatures between 25 and 50°C and at pH values of 5·0-7·0. The two strains and a commercial cellulase (CE) were applied as additives to alfalfa silage. After 60 days of ensiling, the lactic acid in the control and CE groups were significantly lower than those of the other treatment groups. The neutral detergent fibre and acid detergent fibre contents in the LP group were significantly lower than those observed in the other groups. At the same time, the combination of CE and FAE-producing lactic acid bacteria synergistically improved the fermentation quality of the silage. CONCLUSIONS: The addition of the FAE-producing strain of L. plantarum A1 to alfalfa silage improved its fermentation quality, and reduced the fibre content of the silage. SIGNIFICANCE AND IMPACT OF THE STUDY: The screened homo-fermentative and FAE-producing strain of L. plantarum A1 could be a candidate strain in improving fermentation quality and fibre digestibility of ensiled forages.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Elymus/microbiologia , Lactobacillus/metabolismo , Medicago sativa , Silagem/microbiologia , Celulase/metabolismo , Fibras na Dieta/análise , Fermentação , Ácido Láctico/análise , Ácido Láctico/metabolismo , Lactobacillus/enzimologia , Lactobacillus/genética , Medicago sativa/química , Medicago sativa/microbiologia , RNA Ribossômico 16S/genética , Silagem/análise
10.
Ecotoxicol Environ Saf ; 182: 109459, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31344591

RESUMO

The utilization of forages grown on metal-contaminated soil can increase the risk of heavy metals entering the food chain and affecting human health because of elevated toxic metal concentrations. Meanwhile, hydrogen sulfide (H2S) and nitric oxide (NO) as signaling molecules are known to promote plant growth in metal-contaminated soils. However, the regulatory mechanisms of such molecules in plant physiology and soil biochemistry have not been well-documented. Hence, we investigate the role of the exogenous application of H2S and NO on alfalfa growth in lead/cadmium (Pb/Cd)-contaminated soil. Our results indicate that the signaling molecules increase the alfalfa chlorophyll and biomass content and improve alfalfa growth. Further, H2S and NO reduce the translocation and bioconcentration factors of Pb and Cd, potentially reducing the risk of heavy metals entering the food chain. These signaling molecules reduce metal-induced oxidative damage to alfalfa by mitigating reactive oxygen species accumulation and increasing antioxidant enzyme activities. Their exogenous application increases soil enzymatic activities, particularly of catalase and polyphenol oxidase, without significantly changing the composition and structure of rhizosphere bacterial communities. Interestingly, H2S addition enriches the abundance of plant-growth-promoting rhizobacteria in soil, including Nocardioides, Rhizobium, and Glycomyces. H2S is more effective than NO in improving alfalfa growth and reducing heavy-metal contamination of the food chain. These results provide new insights into the exogenous application of signaling molecules in alleviating metal-induced phytotoxicity, including an efficient strategy for the safe use of forages.


Assuntos
Cádmio/análise , Sulfeto de Hidrogênio/farmacologia , Chumbo/análise , Medicago sativa/efeitos dos fármacos , Óxido Nítrico/farmacologia , Poluentes do Solo/análise , Irrigação Agrícola , Biomassa , Cádmio/toxicidade , Fumigação , Sulfeto de Hidrogênio/administração & dosagem , Chumbo/toxicidade , Medicago sativa/química , Medicago sativa/crescimento & desenvolvimento , Microbiota/efeitos dos fármacos , Óxido Nítrico/administração & dosagem , Poluentes do Solo/toxicidade
11.
Nutrients ; 11(5)2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31137802

RESUMO

The polysaccharide isolated from alfalfa was considered to be a kind of macromolecule with some biological activities; however, its molecular structure and effects on immune cells are still unclear. The objectives of this study were to explore the extraction and purifying methods of alfalfa (Medicago sativa L.) polysaccharide (APS) and decipher its composition and molecular characteristics, as well as its activation to lymphocytes. The crude polysaccharides isolated from alfalfa by water extraction and alcohol precipitation methods were purified by semipermeable membrane dialysis. Five batches of alfalfa samples were obtained from five farms (one composite sample per farm) and three replicates were conducted for each sample in determination. The results from ion chromatography (IC) analysis showed that the APS was composed of fucose, arabinose, galactose, glucose, xylose, mannose, galactose, galacturonic acid (GalA), and glucuronic acid (GlcA) with a molar ratio of 2.6:8.0:4.7:21.3:3.2:1.0:74.2:14.9. The weight-average molecular weight (Mw), number-average molecular weight (Mn), and Z-average molecular weight (Mz) of APS were calculated to be 3.30 × 106, 4.06 × 105, and 1.43 × 108 g/mol, respectively, according to the analysis by gel permeation chromatography-refractive index-multiangle laser light scattering (GPC-RI-MALS). The findings of electron ionization mass spectrometry (EI-MS) suggest that APS consists of seven linkage residues, namely 1,5-Araf, galactose (T-D-Glc), glucose (T-D-Gal), 1,4-Gal-Ac, 1,4-Glc, 1,6-Gal, and 1,3,4-GalA, with molar proportions of 10.30%, 4.02%, 10.28%, 52.29%, 17.02%, 3.52%, and 2.57%, respectively. Additionally, APS markedly increased B-cell proliferation and IgM secretion in a dose- and time-dependent manner but not the proliferation and cytokine (IL-2, -4, and IFN-γ) expression of T cells. Taken together, the present results suggest that APS are macromolecular polymers with a molar mass (indicated by Mw) of 3.3 × 106 g/mol and may be a potential candidate as an immunopotentiating pharmaceutical agent or functional food.


Assuntos
Linfócitos B/efeitos dos fármacos , Fracionamento Químico/métodos , Fatores Imunológicos/farmacologia , Medicago sativa/química , Polissacarídeos/farmacologia , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Configuração de Carboidratos , Sequência de Carboidratos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Imunoglobulina M/metabolismo , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Peso Molecular , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Relação Estrutura-Atividade , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo
12.
Int J Biol Macromol ; 133: 1107-1114, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31022488

RESUMO

The effects of alfalfa polysaccharides (APS) on immunomodulatory and antioxidant functions, as well as intestinal morphology were investigated in vivo in this study. Sixty-four mice were randomly divided into four groups and administered 0, 200, 400 or 800 mg/kg/d body weight APS via gavage for 28 days. The blood parameters and metabolites, viscera indices, antioxidant enzyme activities and intestinal morphology were measured. The results showed that the oral administration of APS improved the immune functions of mice, significantly enhanced the white blood cells and lymphocyte counts, and led to improvements in spleen and thymus indices. APS exhibited significant antioxidant activity by enhancing total antioxidant capacity, superoxide dismutase and glutathione peroxidase activities in heart, kidney and liver, and decreasing the malondialdehyde levels of heart and liver. Moreover, administration of APS potently enhanced the small intestinal villous height and the villus-to-crypt ratio, and decreased the crypt depth of duodenum in mice. Therefore, we can conclude that APS possesses pronounced immunomodulatory activities, and plays an important role in the prevention of oxidative stresses and in the improvement of intestinal morphology in the immunological system in vivo. APS thus shows potential for the development as an effective natural immunomodulatory and antioxidant agent.


Assuntos
Antioxidantes/farmacologia , Fatores Imunológicos/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Medicago sativa/química , Polissacarídeos/farmacologia , Animais , Antioxidantes/química , Feminino , Fatores Imunológicos/química , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Camundongos , Polissacarídeos/química , Baço/efeitos dos fármacos , Baço/imunologia , Timo/efeitos dos fármacos , Timo/imunologia
13.
Anal Bioanal Chem ; 411(19): 4937-4949, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30972468

RESUMO

Cell-based assays utilizing reporter gene technology have been widely exploited for biosensing, as they provide useful information about the bioavailability and cell toxicity of target analytes. The long assay time due to gene transcription and translation is one of the main drawbacks of cell biosensors. We report the development of two yeast biosensors stably expressing human estrogen receptors α and ß and employing NanoLuc as the reporter protein to upgrade the widely used yeast estrogen screening (YES) assays. A viability control strain was also developed based on a chimeric green-emitting luciferase, PLG2, expressed for the first time in Saccharomycescerevisiae. Thanks to their brightness, NanoLuc and PLG2 provided excellent sensitivity, enabling the implementation of these biosensors into low-cost smartphone-based devices. The developed biosensors had a rapid (1 h) response and reported on (anti)estrogenic activity via human estrogen receptors α and ß as well as general sample toxicity. Under optimized conditions, we obtained LODs of 7.1 ± 0.4 nM and 0.38 ± 0.08 nM for E2 with nanoYESα and nanoYESß, respectively. As a proof of concept, we analyzed real samples from plants showing significant estrogenic activity or known to contain significant amounts of phytoestrogens. Graphical abstract.


Assuntos
Técnicas Biossensoriais , Disruptores Endócrinos/análise , Medições Luminescentes/métodos , Nanotecnologia , Saccharomyces cerevisiae/metabolismo , Smartphone , Genes Reporter , Limite de Detecção , Luciferases/genética , Medicago sativa/química , Extratos Vegetais/química , Reprodutibilidade dos Testes , Saccharomyces cerevisiae/genética , Soja/química , Poluentes Químicos da Água/análise
14.
J Dairy Sci ; 102(6): 5212-5218, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30981480

RESUMO

Nitrogen concentrations in feeds, feces, milk, and urine samples were measured using 2 analytical methods following different drying procedures. Ten samples of corn silage, alfalfa silage, and concentrates collected from 2017 to 2018 at Krauss Dairy Research Center, The Ohio State University (Wooster), were used. A 4-d total collection digestion trial provided fecal samples from 10 cows (1 sample/cow), and another 10 cows were used to collect milk samples (1 sample/cow) and spot urine samples (1 sample/cow). Spot urine samples were acidified immediately to pH <3.0 when collected. Feed samples were oven dried (55°C) or lyophilized and analyzed using the Kjeldahl (KJ; copper sulfate as a catalyst) method and a combustion method (elemental analyzer; EA). Feces, urine, and milk samples were analyzed for N using the following methods: (1) fresh samples by KJ (referred to as wet KJ), (2) lyophilization (urine and milk for 8 h; feces for 120 h) followed by EA (LYO-EA), and (3) oven drying (milk and urine for 1 h; feces for 72 h at 55°C) followed by EA (OD-EA). Additionally, changes in N content of acidified urine at -20° over 180 d of storage were examined. Nitrogen concentrations in corn silage, alfalfa silage, and concentrates were greater for EA by 6.1, 4.8, and 8.3%, respectively, compared with KJ. Analysis of dried samples via EA compared with wet KJ resulted in lower fecal N content (27.8 vs. 29.3 g/kg of DM). Nitrogen concentration in fecal samples via KJ after lyophilization was lower by 5% compared with wet KJ but did not differ from LYO-EA, suggesting that N losses occurred during drying. Nitrogen determination with EA after drying of samples resulted in greater milk N (5.70 vs. 5.50 g/kg) and urinary N (9.16 vs. 9.06 g/kg) content compared with wet KJ. However, drying method (i.e., lyophilization vs. oven drying) did not affect N content of milk, urine, or feces. The use of EA resulted in lower percentage deviation of N content from duplicate sample assays for most samples (no difference was found for concentrate and fecal N), suggesting that EA was more precise than KJ. In conclusion, drying of feces caused N losses regardless of drying methods. For urine and milk samples, if drying is necessary (i.e., EA), oven drying at 55°C can be used rather than lyophilization. The N content was greater in feeds, milk, and urine when determined with EA versus KJ. In addition, N content in acidified and undiluted urine at -20° changed and should be analyzed within 90 d of storage. The results in the current study, however, did not account for laboratory-to-laboratory variation.


Assuntos
Ração Animal , Bovinos , Leite/química , Nitrogênio/análise , Animais , Dessecação , Dieta/veterinária , Fezes/química , Feminino , Lactação , Medicago sativa/química , Nitrogênio/urina , Silagem/análise , Zea mays/química
15.
J Agric Food Chem ; 67(17): 4793-4799, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31002246

RESUMO

The utilization of the nutrient potential of alfalfa ( Medicago sativa L.) cannot be maximized because of its rapidly degradable protein content in the rumen, leading to waste and various digestive disorders. This might be alleviated if protein-binding proanthocyanidins are present in aerial parts of alfalfa forage in adequate amounts. The Lc (bHLH) and C1 (MYB) genes of maize are transcription factors known to be collectively involved in the regulation of anthocyanin biosynthetic pathways. The objective of this study was to investigate the effect of Lc and C1 gene transformations on the proanthocyanidin content, nutrient composition, and degradation characteristics of proteins and carbohydrates by comparing the transgenic alfalfa with its parental nontransgenic (NT) alfalfa and commercial AC-Grazeland cultivar. The DNA extracted from transgenic plants was tested for the presence of respective transgenes by amplification with specific primers of respective transgenes using PCR. Both Lc-single and LcC1-double transgenic alfalfa accumulated both monomeric and polymeric proanthocyanidins with total proanthocyanidins ranging from ca. 460 to 770 µg/g of DM. The C1-transgenic alfalfa did not accumulate proanthocyanidins similar to NT alfalfa. The C1 gene increased the NPN content significantly only in C1-single and Lc1C1-double transgenic alfalfa. The LcC1 combination seemed to have a synergic effect on reducing sugar in alfalfa. In contrast, the Lc gene appears to have a negative effect on starch content. The C1 gene tended to lower the PB3 content irrespective of the presence of the Lc gene. Although the cotransformation of Lc and C1 increased the total N/CHO ratio compared to Lc single gene transformation, the total N/CHO ratio of transgenic alfalfa was not significantly different from NT. In conclusion, Lc-bHLH single and LcC1 double gene transformation resulted in the accumulation of proanthocyanidins and affected the chemical profiles in alfalfa, which altered ruminal degradation patterns and impacted the nutrient availability of alfalfa in ruminant livestock systems.


Assuntos
Flavonoides/metabolismo , Medicago sativa/genética , Medicago sativa/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , Proantocianidinas/metabolismo , Fatores de Transcrição/genética , Ração Animal/análise , Animais , Bovinos , Medicago sativa/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/genética , Rúmen/metabolismo , Fatores de Transcrição/metabolismo , Zea mays/genética
16.
J Sci Food Agric ; 99(9): 4414-4422, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30859565

RESUMO

BACKGROUND: By-products of the food production chain are gaining importance as feedstuffs for ruminants. Alfalfa silage cake (AC) is an unexploited biorefinery by-product rich in fiber. The aim of this study was to test AC, using an in vitro rumen simulation technique (Rusitec), for its suitability as a fiber source for cattle. Three diets with similar crude protein (CP) content were formulated; they contained the biorefinery by-product AC, the original alfalfa silage (OA), or a fiber-rich hay. As fibrous feedstuffs are known to promote ruminal methanogenesis, we additionally tested a plant extract of Scrophularia striata (60 mg g-1 dry matter) for its methane mitigation and antimicrobial properties. RESULTS: Diets containing AC displayed lower nutrient degradability, with the largest difference in CP degradation (P < 0.001). Sequencing of microbial DNA revealed several effects of the diet and of the addition of S. striata extract, but no inhibitory effect on methanogens. Likewise, methane production, which, in general, is lower with AC and OA diets, was not inhibited by S. striata extract, while the short chain fatty acid (SCFA) profiles were unaffected. CONCLUSION: Although CP degradation of the AC diet was lower, degradation of the fiber fractions was similar among diets. According to the present results, AC can be used as fibrous feedstuff for ruminants. Supplementation with S. striata extract did not inhibit methane formation. © 2019 Society of Chemical Industry.


Assuntos
Ração Animal/análise , Bovinos/metabolismo , Medicago sativa/metabolismo , Extratos Vegetais/metabolismo , Rúmen/metabolismo , Scrophularia/química , Silagem/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais/análise , Ácidos Graxos Voláteis/metabolismo , Medicago sativa/química , Metano/metabolismo , Valor Nutritivo , Extratos Vegetais/análise , Scrophularia/metabolismo , Resíduos/análise
17.
Environ Sci Pollut Res Int ; 26(15): 15300-15313, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30927224

RESUMO

The adsorption properties of alfalfa biochar, which is produced via high-temperature pyrolysis for 3 h, were improved by activating it with acid pickling and reheating for 2 h (named AB). The alfalfa biochar prepared under various conditions, such as ultrapure water washing (named AWB3), acid pickling (named APB3) without reheating and cracking, and pyrolyzing of alfalfa for 5 h before ultrapure water washing (named AWB5) or acid pickling (named APB5), were used as controls. The adsorption capacity of biochars was detected by using p-nitrophenol (PNP) as a model pollutant. The corresponding results showed that the specific surface area (SSA) of AB (119.99 m2 g-1) was substantially higher than those of AWB3 (0.030 m2 g-1), APB3 (2.58 m2 g-1), AWB5 (0.46 m2 g-1), and APB5 (2.10 m2 g-1). The enhancement was primarily a result of the following factor: acid pickling and reheating could effectively remove mineral salts and tars, respectively, thereby opening the inner pores. The removal efficiency for PNP was enhanced from 4.43% (AWB3) and 10.68% (APB3) to 98.35% (AB); further, the adsorption equilibrium data of AB followed the type II Langmuir isotherm well, with a high linear-regression value (R2 = 0.997), low chi-square statistic (χ2 = 0.0009), and RMSE (0.0031). X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) determination confirmed that hydrogen bonds and π-π EDA interactions participated in the adsorption process.


Assuntos
Carvão Vegetal/química , Medicago sativa/metabolismo , Nitrofenóis/metabolismo , Adsorção , Cinética , Medicago sativa/química , Nitrofenóis/química , Espectroscopia Fotoeletrônica , Pirólise , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
18.
Pest Manag Sci ; 75(12): 3153-3159, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30927298

RESUMO

BACKGROUND: Sitona weevils (Coleoptera: Curculionidae) are a species complex comprising pests of many leguminous crops worldwide, causing damage to young plants as adults and to rootlets as larvae, resulting in significant yield losses. Timely detection of migrating adult weevils is needed to determine when deployment of control measures becomes necessary. With the aim of developing plant volatile-based lures for Sitona spp. detection, we investigated the responses of S. humeralis to host plant-related aromatic compounds. RESULTS: In olfactometer studies, both male and female S. humeralis responded positively to the odour of alfalfa flowers, a source of aromatic volatiles. In single sensillum recordings, basiconic sensilla located on the third and fourth terminal segments of the antennal club of both sexes were found to respond to benzaldehyde at doses of 10-5 and 10-4  g, suggesting that the weevil is able to detect this compound at the peripheral sensory level. In field studies, S. humeralis was attracted to benzaldehyde in the spring, but not in the autumn. CONCLUSION: Benzaldehyde, as described in this study, may be a suitable candidate for the development of monitoring tools for S. humeralis. © 2019 Society of Chemical Industry.


Assuntos
Benzaldeídos/metabolismo , Quimiotaxia , Controle de Insetos/métodos , Odorantes/análise , Gorgulhos/fisiologia , Migração Animal , Animais , Feminino , Masculino , Medicago sativa/química
19.
Animal ; 13(9): 1817-1825, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30774050

RESUMO

Globally, there is an increased demand for sustainable protein sources for animal feed. Grass and forage legumes have the yield potential to become such alternatives, but the protein needs to be separated from the fibres. Red clover, white clover, lucerne and perennial ryegrass were fractionated into a green juice and a fibrous pulp in a screw-press and protein was subsequently precipitated. The nitrogen (N) and amino acid composition of the produced fractions was analysed and the digestibility of dry matter (DM) and N was evaluated using a rat digestibility trial. The aim was to determine the effect of fractionation on composition and digestibility in order to evaluate the four plants as potential protein sources for monogastrics. Protein concentrates with CP concentrations of 240 to 388 g/kg DM and fibrous pulps with CP concentrations of 111 to 216 g/kg DM were produced. The sum of all analysed amino acids was highest in the protein concentrates corresponding to a low concentration of non-protein nitrogen ranging from 4.9% to 10.4%. Only small variations were seen in the amino acid compositions of the different plants and fractions. The concentration of the essential lysine and methionine in the protein concentrate ranged from 6.27 to 6.67 g/16 g N and 1.54 to 2.09 g/16 g N for lysine and methionine, respectively. For all plants species, total tract digestibility of DM and standardised N digestibility was significantly higher in the protein concentrates (60.8% to 76.5% and 75.4% to 85.0% for DM and N, respectively) compared to pulp (21.2% to 43.4% and 52.1% to 72.5% for DM and N, respectively). Digestibility of lucerne protein concentrate (76.5% and 85.0% for DM and N, respectively) was higher than of the unprocessed plant (39.6% and 74.9% for DM and N, respectively), whereas for red and white clover no difference was found. The amino acids methionine and cysteine were limiting for pigs and broilers in all fractions regardless of plant origin, and low scores were also found for lysine. The study demonstrated great potential of using green plants as a protein source for monogastrics because of high protein content, balanced amino acid composition and high digestibility of DM and N. The effects of processing and protein precipitation were pronounced in lucerne where significantly improved digestibility was observed in the protein concentrate. The results from the study provide valuable and enhanced knowledge to the production of alternative and sustainable protein sources for monogastric feed.


Assuntos
Aminoácidos/metabolismo , Ração Animal/análise , Nitrogênio/metabolismo , Proteínas/metabolismo , Aminoácidos/análise , Animais , Biomassa , Dieta/veterinária , Digestão , Fezes/química , Lolium/química , Medicago sativa/química , Modelos Animais , Nitrogênio/análise , Ratos , Ratos Wistar , Trifolium/química
20.
J Sci Food Agric ; 99(8): 4029-4035, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30729526

RESUMO

BACKGROUND: Fresh sprouts are healthy foods, low in fats and high in phytochemicals, but have a short shelf-life, hence the need for processing methods that preserve their nutritional value. This work was aimed at evaluating the effect of heat-drying (HD) and freeze-drying (FD) on the phytochemical and fatty acid profiles of alfalfa and flax sprouts, as compared to fresh material. RESULTS: Both FD and HD reduced the phytochemical contents compared to fresh sprouts. FD better preserved phytoestrogens, phytosterols and total tocols compared to HD. However, phytoestrogen and tocol content remained quite high also in HD. The fatty acid profile was affected only by sprouts species, with higher amounts of α-linolenic acid in flax and linoleic acid in alfalfa sprouts. CONCLUSIONS: This work demonstrates that drying does not severely compromise the nutritional value of sprouts and provides a valid support for the choice of the drying method depending on the compound to be preserved, and taking into consideration the different cost of the methods. In addition, sprout powder is easy to handle and, due to its low volume, does not imply a decrease of feed consumption and energy intake, which is relevant in its use as a supplement in human and animal feeding. © 2019 Society of Chemical Industry.


Assuntos
Linho/química , Manipulação de Alimentos/métodos , Medicago sativa/química , Compostos Fitoquímicos/química , Ração Animal/análise , Ácidos Graxos/química , Liofilização , Temperatura Alta , Valor Nutritivo , Fitoestrógenos/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA